Report on the Monitoring of Radionuclides in Fishery Products (March 2011

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Report on the Monitoring of Radionuclides in Fishery Products (March 2011 – March 2016)

October 2017 Fisheries Agency of Japan

Table of Contents

Overview ...... 8

The Purpose of this Report ...... 9

Part One. Efforts to Guarantee the Safety of Fishery Products ...... 11 Chapter 1. Monitoring of Radioactive Materials in Food; Restrictions on Distribution and Other Countermeasures ...... 11 1-1-1 Standard Limits for Radioactive Materials in Food ...... 11 1-1-2 Methods of Testing for Radioactive Materials ...... 12 1-1-3 Inspections of Fishery Products for Radioactive Materials ...... 14 1-1-4 Restrictions and Suspensions on Distribution and Shipping ...... 17 1-1-5 Cancellation of Restrictions on Shipping and Distribution ...... 19 Box 1 Calculation of the Limits for Human Consumption ...... 22 Box 2 Survey of Radiation Dose from Radionuclides in Foods Calculation of the Limits ...... 23 Box 3 Examples of Local Government Monitoring Plan ...... 24

Chapter 2. Results of Radioactive Cesium Inspections for Fishery Products ...... 25 1-2-1 Inspection Results for Nationwide Fishery Products in Japan (in total) ...... 25 1-2-2 Inspection Results for Fukushima Prefecture Fishery Products (all) ...... 26 1-2-3 Inspection Results for Fishery Products (all) from Outside Fukushima Prefecture ...... 29 1-2-4 Trends within Fish Species ...... 31 1-2-5 Inspection Results for Main Target Fish Species of Fishing and Farming by Fiscal Year ...... 39 1-2-6 Concentrations of Radioactive Material in Marine Fish within 20-kilometer Radius of the Fukushima Daiichi NPS ...... 43 Box 4 Fukushima Fishing Trials ...... 44 1-2-7 Screening Test by Prefectural and Municipal Governments ...... 45

Chapter 3. Inspection for Radionuclides Other Than Radioactive Cesium ...... 46 1-3-1 Inspections for Radioactive Strontium etc. by the Japan Fisheries Research and Education Agency ...... 46 1-3-2 Survey of Radionuclides Mentioned in the CODEX Guidelines ...... 53 Box 5 Why weren’t Radioactive Strontium and Plutonium Targeted in the Survey? ...... 57

Part Two. The State of Radionuclides Released into the Environment ...... 60 Chapter 1. Movement of Radioactive Cesium Released into the Environment ...... 60 2-1-1 Intake and Excretion by Fish [41] ...... 60 2-1-2 Movement within the Environment ...... 61

Chapter 2. The Leakage of Contaminated Water into the Fukushima Daiichi NPS Port ...... 62 2-2-1 Impact of Contaminated Water Leakage and Countermeasures ...... 62 Box 6 Quantity of Radioactive Material Leaked into the Ocean (Est.) ...... 64 2-2-2 Concentrations of Radioactive Cesium in Fishery Products ...... 65 2-2-2(1) Comparison of Cesium Concentrations in Fishery Products: Just after the accident and in FY2013 ...... 65 2-2-2(2) Comparison of Before and After the Leakage of Contaminated Water ...... 67 2-2-2(3) Summary ...... 70

Chapter 3. Monitoring of Radionuclides in the Ocean ...... 71 2-3-1 Results from Ocean Water Monitoring (Figure 2-5, Figure 2-6) ...... 71 2-3-2 Results from Marine Soil Monitoring (Figure 2-5, Figure 2-7) ...... 75

Part Three. Research on the Mechanism by which Radionuclides are Transferred to Fishery Products ...... 78 Chapter 1. Relationship with Prey Organisms and Ecology of Fish Species ...... 78 3-1-1 Chronological Changes in the Concentration of Radioactive Cesium in Seawater in Sendai Bay and the Coastal Areas of Fukushima Prefecture ...... 78 3-1-2 Research on Radioactive Materials within Prey Organisms ...... 78 3-1-3 Research on Ecology of Fish Species and the Timing of Radionuclide Transfer ...... 82 3-1-4 Conclusion and Future Research ...... 84

Chapter 2. Urgent Research on the Cause of Contamination of Highly Contaminated Fish (Fat greenling) ...... 85 3-2-1 Frequency of Appearance of Highly Contaminated Fat greenlings ...... 85 3-2-2 Determining the Time of Contamination through Autoradiography Experiment ...... 86 3-2-3 Study on the Migration Ecology and Habitat History of the Fat greenling ...... 87 3-2-4 Estimate of Contamination Source by Contamination Model for the Fat greenling Sample ...... 87 3-2-5 Conclusion and Measures ...... 88

Chapter 3. Evaluation of Radioactive Cesium Transfer from Marine Soil to Marine Organisms based on a Rearing Experiments ...... 89 3-3-1 Outline of the Preparatory Rearing Experiment with Benthos and Fish ...... 89 3-3-2 Results for the Korean lugworms ...... 89 3-3-3 Results for the Olive flounder and Japanese Black porgy ...... 90 3-3-4 On-site Rearing Experiment ...... 91 3-3-5 Outline of Rearing Experiment to evaluate Radioactive Cesium Transfer from Contaminated Marine Soil to Benthos and Demersal Fish ...... 92 3-3-6 Results and a Review of the Water-Tank Rearing Experiment ...... 93 3-3-7 Review and Outlook ...... 95

Chapter 4. Radioactive Material Concentrations and Territories of Fish Species ...... 95

Chapter 5. Quantitative Evaluation of Contamination Risk from Radioactive Material in Fishery Products ...... 98 3-5-1. Means of Predicting the Risk of Contamination from Radioactive Materials in Fishery Products ...... 98 3-5-2. Change in the Probability of the Emergence of Concentrations of Radioactive Cesium in Pacific cod Over Time ...... 102 Chapter 6. Understanding the Mechanism by which Radioactive Cesium is Absorbed into the Soil . 104 Box7 Radioactive Cesium in Demersal Fish ...... 106

Part Four. Efforts to Address Unfounded Reputational Damages and Misinformation Present Domestically and Overseas ...... 107 Chapter 1. Domestic Situation Regarding Unfounded Reputational Damage and Misinformation ... 107

Chapter 2. Enhanced Provision/Dissemination of Information, Domestically and Internationally .... 108

Chapter 3. Response to International Issues ...... 111 4-3-1 Response to Import Restrictions Imposed by Foreign Countries and Regions ...... 111 4-3-2 Response to the Certificates Demanded by Other Countries and Regions ...... 117 4-3-3 Examples of Radioactive Materials Detected in Fishery Products after Exportation from Japan ...... 119 4-3-4 IAEA Evaluation of Food Monitoring ...... 122

Conclusion ...... 124

References ...... 126

Appendix Radioactive Material Analysis Flowcharts ...... 133

Appendix Table Inspection Results for Radioactive Cesium Concentrations in Fishery Products (March 2011 – March 2016) ...... 141

Tables

Table 1-1 Outline of the Fact-Finding Survey on Sampling (as of the End of March 2016) ...... 13 Table 1-2 Inspection Frequency and Target Items (Marine Fish) based on the “Guidelines” ...... 16 Table 1-3 Screening Test by Prefectural and Municipal Governments ...... 45

Table 1-4 Inspection Results for Radioactive Strontium in Fishery Products ...... 48-50 Table 1-5 Examples for Calculating the Eeffective Dose of Strontium-90 ...... 52 Table 1-6 CODEX’s Guideline Levels ...... 54 Table 1-7 Radioactive Material Concentrations in Fishery Products for Radionuclides Noted in the CODEX Guidelines ...... 56 Table 1-8 Half-Lives of Radionuclides that were Considered when Setting Limits ...... 59 Table 2-1 Comparison of Radioactive Cesium in Fishery Products Between Two Periods ...... 66 Table 2-2 Comparison of Radioactive Cesium in Fishery Products Between Two Periods (Results of Statistical Test) ...... 67 Table 2-3 Comparison of Radioactive Cesium Concentrations Before and After the Contaminated Water Leakage Controversy ...... 69 Table 2-4 Comparison of Radioactive Cesium Concentrations Before and After the Controversy over the Leakage of Contaminated Water (Results of statistical test) ...... 70 Table 3-1 Radioactive Cesium Concentration within Benthos Sampled at the Estuary of the Abukuma River ...... 80 Table 3-2 Concentration of Radioactive Cesium in Benthic Organisms Obtained within Twenty Kilometers of the Daiichi Nuclear Power Station in October 2013 ...... 80 Table 3-3 Results of the Korean Lugworm Feeding Experiment ...... 90 Table 3-4 Results of the Still-Water-Tank Feeding Experiment ...... 90 Table 3-5 Probability of Exceeding 100 Bq/kg as of April 1, 2015, based on Model Analysis ...... 99-100 Table 4-1 Import Restrictions Imposed on Fishery Products from Japan as Imposed by Major Countries and Regions (as of March 31, 2016)...... 112-116 Table 4-2 Sampling Standards ...... 118 Table 4-3 Results of Import Inspections by Foreign Countries and Regions for Japanese Food and Fishery Products ...... 120-120

Figures

Figure 1-1 The Fishery Products Monitoring Framework ...... 15 Figure 1-2 Process of the Enactment and Cancellation of Restrictions and Suspensions on Shipping and Distribution (Marine fish) ...... 18 Figure 1-3 Relationships Between the Various Government Organizations ...... 18 Figure 1-4 The Cancellation of Restrictions on the Olive flounder, Miyagi Prefecture ...... 20 Figure 1-5 The Cancellation of Restrictions on the Pacific cod, Aomori Prefecture...... 20 Figure 1-6 The Cancellation of Restrictions on the Pacific cod, Offshore Fukushima Prefecture…….20 Figure 1-7 The State of Distribution Restrictions and Suspensions in Japan (as of March 31, 2016) ... 21 Figure 1-8 Nationwide Fishery Products Inspection Results (in total) (Mar. 2011-Mar. 2016) ...... 26 Figure 1-9 Nationwide Fishery Products Inspection Results (in total) (by fiscal year) ...... 26 Figure 1-10 Inspection Results for Fukushima Prefecture Fishery Products (all) (>100 Bq/kg readings in 3-month periods) ...... 27

Figure 1-11 Inspection Results for Fukushima Prefecture Fishery Products (all) (by fiscal year) ...... 27 Figure 1-12 Inspection Results for Fukushima Prefecture Marine Fish Species (>100 Bq/kg readings, by 3-month periods) ...... 28 Figure 1-13 Inspection Results for Fukushima Prefecture Marine Fish Species (by fiscal year) ...... 28 Figure 1-14 Inspection Results for Fukushima Prefecture Freshwater Species (>100 Bq/kg readings,by 3-month periods) ...... 28 Figure 1-15 Inspection Results for Fukushima Prefecture Freshwater Species (by fiscal year) ...... 28 Figure1-16 Inspection Results for Non-Fukushima Prefecture Fishery Products (all) (>100 Bq/kg readings, by 3-month periods) ...... 29 Figure 1-17 Inspection Results for Non-Fukushima Prefecture Fishery Products (all) (by fiscal year) ... 29 Figure1-18 Inspection Results for Non-Fukushima Prefecture Marine Fish Species (>100 Bq/kg readings, by 3-month periods) ...... 30 Figure 1-19 Inspection Results for Non-Fukushima Prefecture Marine Fish Species (by fiscal year) ..... 30 Figure 1-20 Inspection Results for Non-Fukushima Prefecture Freshwater Fish Species (>100 Bq/kg readings, by 3-month periods) ...... 30 Figure 1-21 Inspection Results for Non-Fukushima Prefecture Freshwater Fish Species (by fiscal year) 30 Figure 1-22 Inspection Results for Surface-layer Fish, Migratory Fish, Squid and Octopus ...... 32 Figure1-23 Nationwide Inspection Results for Surface-layer Fish (Japanese sandlance, Whitebait (juvenile anchovy)) (by fiscal year) ...... 32 Figure 1-24 Nationwide Inspection Results for Chub mackerel and Southern mackerel (by fiscal year) . 32 Figure 1-25 Inspection Results for Seabass (by fiscal year) ...... 33 Figure 1-26 Inspection Results for Crabs, Shrimp, Shellfish and Seaweeds ...... 34 Figure 1-27 Nationwide Inspection Results for Shellfish (Japanese littleneck clam, Common orient clam, Surf clam, Oysters, Abalones and Japanese whelk) (by fiscal year) ...... 34 Figure 1-28 Inspection Results for Shallow-bottom flounders (Marbled flounder and Stone flounder) (by fiscal year) ...... 35 Figure 1-29 Inspection Results for Littlemouth flounder (by fiscal year) ...... 35 Figure 1-30 Inspection Results for Deep-bottom Flounders (Flathead flounder, Roughscale sole and Willowy flounder) (by fiscal year) ...... 36 Figure 1-31 Inspection Results for Olive flounder (by fiscal year) ...... 36 Figure 1-32 Nationwide Inspection Results for Pacific cod (by fiscal year) ...... 37 Figure 1-33 Nationwide Inspection Results for Alaska pollock (by fiscal year) ...... 37 Figure 1-34 Nationwide Inspection Results for Red seabream ...... 37 Figure 1-35 Inspection Results for the Rockfish Family (Goldeye rockfish, Rockfish (Sebastes cheni), Fox jacopever) (by fiscal year) ...... 38 Figure 1-36 Inspection Results for Whitespotted char (wild) and Landlocked salmon (wild) (by fiscal year) ...... 38 Figure 1-37 Inspection Results for Main Target Species of Fishing and Farming (by fiscal year) ...... 39-42 Figure 1-38 Changes in Radioactive Cesium Concentrations within Fish Sampled within 20 km of the Fukushima Daiichi NPS...... 43

Figure 1-39 Sampling Sites ...... 51 Figure 1-40 Preparation of the Sample ...... 58 Figure 1-41 Germanium Semiconductor Detector ...... 58 Figure 1-42 Ash Sample for Measurement of Radioactive Sr and Pu ...... 59 Figure 1-43 Gas-Flow GM Counter (Beta-ray Counter) ...... 59 Figure 2-1 Intake of Radioactive Materials by Fish ...... 61 Figure 2-2 Progression of Contamination due to the Nuclear Accident ...... 62 Figure 2-3 Results of the Monitoring of Radioactive Cesium in Seawater and Marine soil off the Coast of Fukushima ...... 62 Figure 2-4 Impact of Contaminated Water Leakage into the Fukushima Daiichi NPS Port ...... 63 Figure 2-5 Sampling Points in the Vicinity of the Fukushima Daiichi NPS ...... 72 Figure 2-6 Changes in the Radioactive Material Concentrations in the Vicinity of the Fukushima Daiichi NPS and Coastal Ocean Waters ...... 73-74 Figure 2-7 Radioactive Materials Concentrations in Marine Soil in the Vicinity of the Fukushima Daiichi NPS and Coastal Sea Area ...... 76-77 Figure 3-1 Chronological Changes of the Concentration of Cesium-137 in Seawater off the Coast and in Offshore Areas of Fukushima and Miyagi Prefectures ...... 79 Fihure 3-2 Chronological Trend of Cs-137 Concentration within Zooplanktons ...... 79 Figure 3-3 Survey Points for Radioactivity in Benthos off the Coast of Fukushima Prefecture in October 2013 ...... 81 Figure 3-4 Chronological Trend of Radioactive Cesium Concentration within Pacific cod Sampled Offshore Fukushima ...... 82 Figure 3-5 Olive flounder, by Birth Year Class: Relationship between the Number of Days Elapsed Since the Fukushima Daiichi NPS Accident and Radioactive Cesium Concentrations ...... 83 Figure 3-6 Relationship between the Length of and Radioactive Cesium Concentration in Olive flounder, by Birth Year Class ...... 83 Figure 3-7 Radioactive Cesium Concentrations within Fat greenlings Offshore Fukushima ...... 85 Figure 3-8 Analysis of the Fukushima Daiichi NPS Port Brassblotched rockfish Otolith ...... 86 Figure 3-9 Analysis of the Highly-Contaminated Fat greenling’s Otolith ...... 86 Figure 3-10 Simulation Model of Radioactive Cesium Concentrations within Fat greenling...... 88 Figure 3-11 Cages Set up in the Tomioka Fishing Port...... 91 Figure 3-12 Cage-testing Results ...... 92 Figure 3-13 Temporal Trends of Cs-137 Concentrations in Benthos and Marine Soil through the Benthic Food Web in Rearing Tanks ...... 93 Figure 3-14 Temporal Trends of Cs-137 Concentrations in Fat greenlings and Marine Soil in Rearing Tanks...... 94 Figure 3-15 Simulation on Changes in Radioactive Cesium Concentrations within Olive flounder ...... 97 Figure 3-16 Decrease in Radioactive Cesium Concentrations within Japanese amberjack of Iwate Prefecture and Ocellate spot skate of Fukushima Prefecture ...... 101 Figure 3-17 Chronological Changes of the Probability that Concentrations of Radioactive Cesium will

Appear within Pacific cod ...... 103 Figure 3-18 Collective Structural Changes Induced by Cs+ Absorption to Vermiculite Clay ...... 105 Figure 3-19 Absorption of Cesium One after Another like “Domino Toppling” and Schematics of Structural Change of Vermiculite ...... 105 Figure 4-1 Labelling of Harvest Area in the Pacific off the East Coast of Japan [83] ...... 109 Figure 4-2 Publishing Inspection Results and Q&As on the Fisheries Agency Website ...... 110 Figure 4-3 Briefing Sessions for Foreign Press, etc...... 110 Figure 4-4 Inspection for Radioactive Cesium with Gamma Ray Spectrometry ...... 118 Figure 4-5 Review by the IAEA [86] ...... 122 Figure 4-6 Interlaboratory Comparisons Pertaining to Measurements of the Radioactivity of Fishery Products Taken by the IAEA and Japanese Analysis Laboratories [87] ...... 123

Overview

Since the accident at the Fukushima Daiichi Nuclear Power Station (NPS) operated by the Tokyo Electric Power Company (TEPCO) in March 2011, the Government of Japan, concerned local governments, and concerned organizations have joined forces to ensure the safety of fishery products by, for example, monitoring fishery products and restricting shipments when limits are exceeded. This report provides a comprehensive evaluation of the results of monitoring radioactive materials in fishery products in the years after the accident at TEPCO’s Fukushima Daiichi NPS. This evaluation found that, although in the immediate aftermath of the accident a considerable number of fish species, primarily off the coast of Fukushima, were found to contain radioactive cesium in quantities exceeding the limit of 100 Bq/kg, these concentrations decreased with the passage of time, and now, five years after the accident, almost no species are found to exceed the 100 Bq/kg limit. That said, “shipping and distribution restrictions” that are based on the “Concepts of Inspection Planning and the Establishment and Cancellation of Items and Areas to which Restriction of Distribution and/or Consumption of Foods concerned Applies” issued by the National Emergency Response Headquarters remain in place for some regions and species. Accordingly, these regions and species remain out of the market. Regarding radionuclides in fishery products other than radioactive cesium, 104 samples were inspected for radioactive strontium and 18 samples were tested for plutonium between the time of the accident and March 2016. It was discovered that, in all but three of the samples for radioactive strontium and all of the samples for plutonium, their concentrations were extremely low, and at pre-accident levels. The estimation results of the annual effective dose from radioactive strontium in those three samples, which are slightly higher than that in pre-accident, were not problematic. TEPCO announced the leakage of contaminated groundwater into the area inside the port in July 2013. TEPCO further announced in February 2015 that contaminated rainwater had been flowing to the area outside the port since April 2014. However, the monitoring results found no effect of these leakages upon ocean waters outside the port or upon fishery products there in terms of food safety. Additionally, sub-draining operations at the Fukushima Daiichi NPS began in September 2015, then sea-side impermeable wall was completed in October of that year, furthermore frozen-soil walls had been completed except for the part of the depth in March 2018. These preventive and multilayered countermeasures to deal with contaminated water are being implemented. As a result, the generation of contaminated water has been reduced from about 500 to 200 tons per day. In order to secure the safety of fishery products and establish the trust of consumers, the Government of Japan will continue, as its responsibility, to monitor the levels of radionuclides in fishery products. It will also endeavor to shed light on contamination mechanisms so that it can explain the factors behind the occurrence of contaminated fish, and develop predictions concerning reductions of such contaminations in fish to fishery operators and consumers. The Government of Japan will also disseminate accurate information concerning the safety of fishery products in Japan and abroad while also working to address unfounded concerns about fishery products and relax and lift import restrictions by other countries and regions. 8

The Purpose of this Report

The Great East Japan Earthquake and tsunami on March 11, 2011, caused a nuclear accident at the TEPCO’s Fukushima Daiichi Nuclear Power Station (NPS). This accident resulted in the emission of 15 radioactive cesium (Cs-137) at a quantity estimated at 8 to 37 PBq (1 PBq = 10 Bq) [1].

Since March 2011, the Government of Japan, local governments and relevant organizations have monitored the levels of radioactive materials in fishery products in a concerted manner. The monitoring has been carried out in accordance with “Concepts of Inspection Planning and the Establishment and Cancellation of Items and Areas to which Food Distribution and/or Consumption Restriction concerned Applies” [2] of the Nuclear Emergency Response Headquarters, and the results of this monitoring show that at present, five years since the accident, the proportion of fishery products containing radioactive cesium in excess of the limit of 100 Bq/kg has greatly decreased in all prefectures monitored, including Fukushima.

However, although it has been five years since the accident, restrictions based on the aforementioned “concepts” and suspensions remain in effect on the distribution of certain fish species in prefectures ranging from Iwate to Chiba and in Gunma. Commercial fishing operations off Fukushima in particular are suspended and operations are limited to fishing trials on species and in ocean areas that have been confirmed as safe, meaning that fishing activities are very limited compared to those before the accident.

Moreover, the Fukushima Daiichi NPS accident brought about considerable consumer unease, both domestically and internationally, with respect to the safety of fishery products, and even products from regions that were not subject to distribution restriction orders continue to be avoided by consumers due to unfounded reputational damages or misinformation. Concerns over radioactive contamination of fishery products in the Fukushima area reemerged in July 2013, when TEPCO announced the leakage of contaminated water. In response, the Consumer Affairs Agency and other related government agencies joined with local governments, consumer groups, and others to engage in “risk communication” and a nation-wide dialogue on the topic of radioactive materials within foods among specialists, consumers, operators and the Government [3].

In May of 2014, the Fisheries Agency conducted a comprehensive analysis of monitoring data collected over the course of three years following the accident in order to make them useful to not only general consumers, local governments, and overseas governments but also analyses by scientists. It published a report showing trends revealed in the results of the three-year monitoring and an explanation of the data’s significance.

However, regularly conducted consumer surveys by the Consumer Affairs Agency reveal unfounded reputational damages or misinformation. Specifically, the percentage of consumers stating that they “hesitate to buy food products made in Fukushima because they wish to buy food that does not contain 9 radioactive materials” was 19.4 % in February 2013 (compared to the total), 17.9 % in August 2013, 15.3 % in February 2014, 19.6 % in August 2014, 17.4 % in February 2015, 17.2% in August 2015, and 15.7% in February 2016. Thus, it is apparent that concerns remain among some consumers [4]. Further, according to a questionnaire survey conducted between November 2015 and January 2016 by the Fisheries Agency on the state of recovery from the Great East Japan Earthquake in the marine product processing industries of Aomori, Iwate, Miyagi, Fukushima, and Ibaraki Prefectures, 44 % of respondents said that “unfounded reputational damages and misinformation and securing sales channels” is a major “problem in reconstruction efforts”. This figure matched that shown in a previous survey (conducted at the end of FY2014). This outcome demonstrates that, although five years have passed and radioactive material concentration levels within fishery products have fallen, misinformation continues to cause damage [5; 6; 7].

After the accident, many countries and regions imposed import t restrictions that included requirement of test certificate of radionuclides for exports of Japanese fishery products and ban on import of fishery products from certain prefectures. Although more and more countries and regions are relaxing or lifting their restrictions with the passage of time, some countries and regions, such as China (banning of imports from ten prefectures) and Taiwan (banning of imports from five prefectures), continue to maintain them .Additionally, after TEPCO announced in July 2013 that contaminated groundwater had leaked into a port area, the Republic of Korea in the following September strengthened its import regulations by banning imports of fishery products from eight prefectures. This was despite the fact that, according to monitoring results announced by the Government of Japan, no impact on seawater or fishery products was observed outside the port. Such developments suggest that countries and regions continue to have strong concerns vis-à-vis Japan’s fishery products.

Five years after the accident occurred, concentrations of radioactive materials in fishery products have further declined, such that radioactive cesium is now either not detected at all or is only detected at extremely low concentrations across almost all fish species and regions. By conducting evaluations over the five-year period after the disaster struck with the addition of new data and introducing accumulated survey research results, the Fisheries Agency has updated and released this report in order to disseminate accurate information on the current concentration of radioactive materials in fishery products and the safety of those products to people in Japan and abroad, dispelling unfounded concerns, and achieving the relaxation or lift of import restrictions imposed by foreign countries and regions.

Part One. Efforts to Guarantee the Safety of Fishery Products Chapter 1. Monitoring of Radioactive Materials in Food; Restrictions on Distribution and Other Countermeasures

After the Fukushima Daiichi NPS accident in March 2011, standard limits were set on permissible amounts of radioactive materials in food. National and prefectural governments coordinated with relevant bodies to ensure, through monitoring and monitoring-based distribution restrictions, that only fishery products containing levels of radioactive cesium below the limit were allowed to distribute to market for consumption (Figure 1-1 to 3). Additionally, after the accident, coastal fishing and bottom trawling in the waters surrounding Fukushima experienced suspensions of operations. Today, in the interest of carefully resuming fishing operations in the future, thorough inspections and gradual fishing trials are being undertaken only on fish species that have consistently demonstrated levels of radioactive materials below the limits. This chapter will explain these efforts being made to guarantee the safety of these fishery products.

1-1-1 Standard Limits for Radioactive Materials in Food After the Fukushima Daiichi NPS accident, the Ministry of Health, Labour and Welfare on March 17, 2011, established provisional regulation values for radioactive materials in food. (For fish and shellfish, the value for a radioactive cesium was 500 Bq/kg [set March 17], and the value for radioactive iodine was 2,000 Bq/kg [set April 5]). The permissible dosage of exposure from food was, as an emergency response measure, set to an effective dosage of 5 mSv annually for radioactive cesium, and set to a thyroid equivalent dosage of 50 mSv annually for radioactive iodine. The provisional regulation values were enacted under emergency circumstances in accordance with Food Safety Basic Act Article 11, paragraph (1), item (iii), and hence did not receive a Risk Assessment of the Effect of Food on Health from the Food Safety Commission. Hence, on March 20 of the same year (April 6 for fish and shellfish containing radioactive iodine), in accordance with Article 11, paragraph (2) of the same law, the Minister of Health, Labour and Welfare submitted a request for Risk Assessment of the Effect of Food on Health to the Committee Chairman of the Food Safety Commission. On October 27, the Committee Chairman of the Food Safety Commission reported the following findings to the Minister of Health, Labour, and Welfare: “The Food Safety Commission has determined that radiation in food has an impact on health at quantities amounting to a lifetime accumulated effective dose of 100 mSv or more, ignoring normal radiation exposure experienced in everyday life.” [8]. Although food items that conformed to provisional regulation values had been generally judged to have no negative effects on health and to be safe, new limits were established after the Food Safety Commission report in order to achieve still greater food safety. These new limits were intended for the long-term established taking into the factors such as the guidelines proposed by the Codex Alimentarius Commissionbguidelines [9], a Values are set by taking into account the contribution of radioactive strontium. b The Codex Alimentarius Commission is an international intergovernmental body that was established by the FAO and WHO in 1963. Its purpose is to protect the health of consumers and ensure fair trade of food products. Among other activities, it develops international food standards (the Codex Alimentarius). Japan became a member

11 which adopt the 1 mSv per annum intervention exemption levelcfor food, and were intended for the long-term. Following review by the Radiation Council and the Pharmaceutical Affairs and Food Sanitation Council [10], the allowed dosage of radiation exposure from food was reduced to 1mSv per annum. New limits based on these developments were established on April 1, 2012. The new limits set radioactive cesium as the representative radionuclide, due primarily to its large effect on internal radiation exposure relative to other radionuclides considered (plutonium, strontium-90, and ruthenium-106). Therefore, if radioactive cesium concentrations are found by inspection to be within the limits, the food is considered to be safely distributed to market with the effect of strontium 90 and other radionuclides taken into account. The new limits on radioactive cesium are set for four food categories (drinking water, infant foods, milk, and general foods). Fishery products are classified as “general foods” and hence the limit is 100 Bq/kg. There is no set limit for radioactive iodine, which has a short half-life and has come to be undetectable.

1-1-2 Methods of Testing for Radioactive Materials For the gathering of samples, the Fisheries Agency has given guidance to local governments and other organizations that the sampling operators should gather approximately 5 kg or more of each fish species (as many individual fish as possible) and record the time and location that each sample was collected. Ensuring the fairness of sampling is necessary from the standpoint of maintaining testing objectivity. The Fisheries Agency administered a survey of actual conditions on the collection of samples to key local governmentsd engaged in monitoring activities. The results show that sampling is handled by employees of individual markets or fishery cooperatives. Moreover, it can be judged from the landed catches that sampling is being conducted in a fair and appropriate manner (Table 1-1). The methods by which radioactive cesium concentration is measured in fishery products include a gamma ray spectrometry radionuclide assay method that utilizes a germanium semiconductor detector, carried out in accordance with the Ministry of Health, Labour, and Welfare’s local government-oriented notification, “Testing Methods for Radioactive Materials in Food” (March 15, 2012) [11]. Another method is the NaI scintillation spectrometer method pursuant to the “Partial Revision of the Screening Methods for Radioactive Cesium in foods” (Partially revised on March 1, 2012) [12]. These notifications establish guidelines to ensure the credibility of radioactive material monitoring by establishing practices such as the daily measurement of background radiation, the periodic use of a standard radiation source for calibration, etc. Inspections and monitoring carried out in accordance with these reports help to establish the credibility of the results. In the case of the gamma ray spectrometry using a germanium semiconductor detector, there are limitations to how efficiently a large number of samples can be inspected, such as that it requires rare equipment available in limited numbers, or that relatively many samples are required. With these factors in mind, the screening method used in monitoring practices was established with the objective of detecting samples that

c “Intervention Exemption level” is the level at which no special measures are considered to be necessary. d The survey targeted and obtained responses from major local governments that conduct monitoring (Aomori Prefecture, Iwate Prefecture, Miyagi Prefecture, Fukushima Prefecture, Ibaraki Prefecture, and Chiba Prefecture). Monitoring is also conducted by other prefectures and fishing industry organizations.

12 have radioactive cesium concentrations that are clearly and definitively lower than the provisional regulation values. The Method was then amended when the newer limits were established. Under the new limits, the screening cut-off was applied to any reading over 1/2 (50 Bq/kg) the limit, with a measurement lower bound of 25 Bq/kg (1/4 the limit). If a sample’s reading exceeds the screening cut-off and it is impossible to determine with certainty that radioactive cesium concentrations are below the limits, the sample will undergo further analysis via gamma ray spectrometry using a germanium semiconductor detector, to more precisely determine concentrations.e This method is employed in Fukushima fishing trials, the fish market, and other settings.

Table 1-1 Outline of the Fact-Finding Survey on Sampling (as of the end of March 2016)

Question Aomori Prefecture Iwate Prefecture Miyagi Prefecture Fukushima Prefecture Ibaraki Prefecture Chiba Prefecture In principle, the catch of a single boat is used. Do you consider one sample to However, if the catch is be the catch of a single boat or The catch of one boat is The catch of one boat is The catch of one boat is The catch of one boat is The catch of one boat is 1 small, we sometimes the combined catch of several used. used. used. used. used. combine it with the catch boats? of another operating in the same region. Coastal fishery is We choose boats We choose boats We choose boats We choose boats that We choose boats that voluntarily suspended. A How do you choose the boats randomly without much randomly without much randomly in the market, 2 catch many fish of the catch many of the rotation of fishing boats you use for sampling? thought for particular thought for particular without much thought for standard size. targeted fish. takes turns going out to boats. boats. particular boats. collect samples. If targeted fish species are We place priority on brought in using different fishing offshore trawl fishery We use fixed nets or the We put priority on the We use the method that Samples are handled by Samples are handled by 3 methods, how do you choose (because it allows method that catches the method that catches the catches the most fish. fishing method. fishing method. the methods to be used for accurately checking the most fish. most fish. sampling? catch locations)

If targeted fish species are caught and brought in from Yes different points in a surveyed We place priority on 4 Yes No Yes No Yes sea region, do you consider the using fish caught along points that the fish were caught the coast. when choosing samples? Do you give priority to a We choose the size that We use typical sizes We choose the size that We use large fish (in Samples are made to 5 particular size when collecting can be landed in the (both large and small for can be landed in the We use typical sizes. consideration of safety) include various sizes. samples? largest quantities. specific species). largest quantities. 1) Yes, but only for fish species targeted by If you cannot obtain the sample intensified inspection. quantity needed for 1) Yes 2) We mix the catch 6 measurement, do you 1) submit 1) No such case thus far 1) No 1) No 1) No 2) It is joined with the with catches from other the sample and 2) if so, how do following day’s catch. boats or from later days, you submit the sample? but only when caught in the same sea region. 1) Freezing or 1) Ice storage or 1) Ice storage or How do you 1) store samples 1) Freezing 1) Ice storage 1) Ice storage refrigeration freezing freezing 7 and 2) send samples to 2) Parcel delivery 2) Parcel delivery 2) Parcel delivery 2) Parcel delivery 2) Parcel delivery 2) Parcel delivery inspecting organizations? service service service service or collection by service service local governments Samples are collected At least two people each by prefectural How many people are in charge Two or three people per 1 person in charge with One or two people per One or two people per 8 in major fish markets employees who handle of sampling? sea region. two people in support fishery cooperative fishery cooperative that conduct monitoring monitoring (2 or 3 per sea region). Do people in charge of submitting samples receive Training and briefings 9 explanations or training on Training is provided. Briefings are provided. Briefings are provided. are organized by the Briefings are provided. Briefings are provided. methods for submitting prefecture. samples? Have any changes been made Yes to the sample submittal No 10 No No The priority species No No process? If so, what changes were changed, etc. were made?

e Information on inspection equipment suitable for this screening method can be found on the JRIA website: http://www.jrias.or.jp/products/info/706.html

1-1-3 Inspections of Fishery Products for Radioactive Materials Since the Fukushima Daiichi NPS accident, the Fisheries Agency has coordinated with prefectural governments and fishing organizations to systematically monitor radioactive materials in fishery products, in accordance with the Nuclear Emergency Response Headquarters’ “Concepts of Inspection Planning and the Establishment and Cancellation of Items and Areas to which Restriction of Distribution and/or Consumption of Foods concerned Applies” (hereafter referred to as “Guidelines,” announced April 4, 2011; latest revision March 25, 2016) (Table 1-2) [2]. These Guidelines outline for local governments the basic concepts (target products, frequency of inspections, etc.) of monitoring practice. The Guidelines have been revised over time as needed, based on results and data accumulated since the Fukushima Daiichi NPS accident, in order to focus inspections on categories of items in which higher concentrations of radioactive cesium have been detected (Table 1-2). To be more concrete, as with normal food, local governments take the lead and establish quarterly monitoring plans that detail target fish species, inspection frequency, and other topics. These plans are created with due consideration of the Guidelines and species of fish harvested. In accordance with these monitoring plans, marine fish areas are divided into various zones, and in each zone pre-shipment inspections of fish are conducted on a weekly basis on major fishery products in related prefectures and on specific fishery products that exceeded 50 Bq/kg in the previous year (Figure 1-1). Based on the cumulative inspection results, when the Guideline were revised on March 25, 2016, it was decided to maintain that fish species exceeding 50 Bq/kg and fish species that did not exceed 50 Bq/kg but for which attention was necessary continue to subject to the inspections, as well as previous revision of the Guideline (Table 1-2). Fishery species live in a wide variety of environments, including the ocean surface, midwater, and the bottom, at various stages of their life cycles, and undertake various kinds of migrations. Fishery species are also consumed differently, some eaten whole and some in fillet, differing from species to species. With these factors under consideration, sampling is taken of fishery species representative of each sea zone and habitat, and samples taken of the fish’s edible portions for readings (e.g., the muscular sections for large fish that are eaten in fillet, the entire body for small fish that are eaten whole, etc.). If, in the course of closely following the outcomes of the above monitoring processes in the relevant prefectures, one prefecture is discovered to have particularly high levels of contamination, neighboring prefectures are notified immediately and inspections are intensified on the fish species and other species living in similar habitats.

Figure 1-1 The Fishery Products Monitoring Framework

Table1- 2 Inspection Frequency and Target Items (Marine Fish) based on the “Guidelines”

Items from which more (Reference) Items from which between 50 than 100 Bq/kg of Items not exceeding 50 Bq/kg but attention is and 100 Bq/kg of radioactive Category radioactive cesium has required based on the results of inspections cesium has been detected been detected conducted on items in the same categories or （b） Date: March 20, 2015 (a) the past inspections on the items concerned Japanese scad Japanese scad Olive flounder Olive flounder

Righteye flounders （habitat Red tonguesole; Black cowtongue; Spotted zone is mainly shallower than Marbled flounder; Stone flounder Note: Classified based halibut; Ridged‐eye flounder; Starry flounder depth of water 100 meters.) Righteye flounders (habitat Roughscale sole; Barfin flounder; Willowy on maximum zone is mainly deeper than Slime flounder Flathead flounder; Shotted halibut flounder depth of water 100 meters.) radioactive cesium Fat greenling Fat greenling Rockfish, Jacopever and Scorpion fish（habitat zone is Rockfish (white colour); Goldeye Black rockfish; Rockfish (black colour); Snowy Brassblotched rockfish concentration values mainly shallower than depth of rockfish; Fox jacopever; rockfish; Scorpion fish water 100 meters.) Rockfish, Jacopever and from monitoring Scorpion fish（habitat zone is Matsubara's red rockfish; Sea raven mainly deeper than depth of conducted between water 100 meters.) Shark and Stingray Ocellate spot skate Starspotted smooth‐hound; Pitted stingray

April 1, 2014, and Pacific cod Pacific cod

Brown hakeling Brown hakeling Marine fishery products February 28, 2015. Poacher (saburo), Japanese Spiny red gurnard; Poacher (saburou); Japanese prickleback, Nibe croaker prickleback; Nibe croaker

Largehead hairtail Largehead hairtail

Japanese black porgy, Striped Japanese black porgy Japanese surfperch; Striped mullet mullet, Japanese surfperch

Japanese seabass Seabass

Puffer Panther puffer

Conger eel Congrid eel; Beach conger; Beach conger

Bartail flathead Bartail flathead

Japanese sandlance (adult) Japanese sandlance

Japanese littleneck clam Japanese littleneck clam

Items from which more (Reference) Items from which between 50 than 100 Bq/kg of Items not exceeding 50 Bq/kg but attention is and 100 Bq/kg of radioactive Date: March 25, 2016 Category radioactive cesium has required based on the results of inspections cesium has been detected been detected conducted on items in the same categories or （b） (a) the past inspections on the items concerned Japanese scad Japanese scad

Note: Classified based Olive flounder Olive flounder

Righteye flounders （habitat Red tonguesole; Black cowtongue; Starry zone is mainly shallower than Stone flounder; Marbled flounder; on maximum flounder; Spotted halibut depth of water 100 meters.) Righteye flounders (habitat radioactive cesium zone is mainly deeper than Slime flounder Barfin flounder depth of water 100 meters.) concentration values Fat greenling Fat greenling

Rockfish, Jacopever and from monitoring Scorpion fish（habitat zone is Fox jacopever; Rockfish (white colour); Goldeye rockfish; Scorpion fish; Black rockfish; mainly shallower than depth of Brassblotched rockfish Rockfish (black colour) water 100 meters.) conducted between Stingray Red stingray; Ocellate spot skate April 1, 2015, and Pacific cod Pacific cod Brown hakeling Brown hakeling

February 29, 2016. Marine fishery products Poacher (saburo), Japanese Poacher (saburo), Japanese prickleback, prickleback,

Japanese black porgy Japanese black porgy

Japanese surfperch Japanese surfperch

Japanese seabass Japanese seabass

Conger eel Conger eel

Bartail flathead Bartail flathead

Japanese sandlance (adult) Japanese sandlance (adult)

Common octopus Common octopus

Inspections of marine fish are conducted under the Guidelines in Fukushima, Miyagi, and Iwate prefectures. In principle, inspections

are conducted approximately once a week. For items that have a fishery season, inspections are conducted prior to the start of the fishery

season and continue to be conducted approximately once per week after the fishery season begins.

1-1-4 Restrictions and Suspensions on Distribution and Shipping In cases where the same fishery products at multiple locations along a prefecture’s coast exceed the limits and other situations in which it seems that an item might exceed the limits across an entire region, the Act on Special Measures Concerning Nuclear Emergency Preparedness, Article 20, paragraph 2 dictates that that the head of the Nuclear Emergency Response Headquarters (i.e., the Prime Minister of Japan) will impose restrictions on the distribution and shipping of the food item. Should such restrictions be imposed, local governments issue appeals to fishing industry organizations and those affiliated with the market and distribution to prevent the target food items from reaching the market. In order to lift shipping restrictions, inspection results will at least need to be consistently below limits for the last month at multiple locations. Products exceeding the limits will be judged to be in violation of the Food Sanitation Act, collected, and discarded without reaching market (Figure1-2) The standards of the above restrictions and their subsequent cancellation are set by the Nuclear Emergency Response Headquarters’ Guidelines. If fishery samples in multiple places in the same inspection zone are found to exceed the limits, it is regarded that the contamination is in the state of “regional spread”. Should one instance of limit-exceeding results appear within a sea zone, it will become the focus of subsequent inspections. However, in this case, there is a possibility of “regional spread” of contamination throughout the relevant zone, and therefore local governments appeal to fishing industry organizations to suspend shipping and distribution until safety has been determined through focused inspections, at which point the suspensions may be canceled. The term “suspensions” may seem to imply that these suspensions are somewhat voluntary, but the items subject to the suspension are announced publicly, and they are imposed with the cooperation of fishing industry organizations in the same manner as government-imposed restrictions. Hence, until the appeal for suspensions is canceled, relevant parties engage in preventing the target goods in the target zone from reaching the market. Specifically, through extensive publicity and leadership from the fisheries cooperatives toward fishermen, as well as the cooperation of companies affiliated with distribution and the market itself to cease handling the target product (or to clearly label those items of the same type but shipped in from other regions), this “suspension” truly is being implemented. The current situation of the distribution restriction and suspension is shown in Figure 1-7.

The items are listed in public, preventing it from being distributed in the market.

Figure 1-2 Process of the Enactment and Cancellation of Restrictions and Suspensions on Shipping and Distribution (Marine fish)

Figure 1-3 Relationships between the Various Government Organizations

1-1-5 Cancellation of Restrictions on Shipping and Distribution Radioactive cesium concentrations have dropped since the Fukushima Daiichi NPS accident, and now restrictions on shipping and distribution are gradually being canceled. For example, the restrictions have been lifted as follows in Fukushima Prefecturef : two species – flathead flounder and Alaska pollack – in FY2013; nine species – including littlemouth flounder, Pacific cod, and shotted halibut – in FY2014; and four species – including nibe croaker, panther puffer, and ridged-eye flounder – in FY2015. To apply for a cancellation of restrictions on shipping and distribution, local governments must demonstrate that their inspection results are consistently below the limits. Shipping and distribution restriction orders will not be canceled until this application for cancellation is judged to be appropriate. Moreover, at the time that restrictions on shipping and distribution are lifted, local governments must present post-cancellation shipping and distribution management plans and inspection plans. They must also continue practicing appropriate monitoring and management after the restrictions are lifted. Examples of applications made for restriction cancellation include the cancellation of restrictions on the olive flounder (Paralichthys olivaceus) in Miyagi Prefecture on April 1, 2013. The inspection results for this application can be found in Figure 1-4 below. Since a reading of 140 Bq/kg emerged on September 4, 2012, the highest reading out of 110 inspected samples was 51 Bq/kg, with a median reading of 8.3 Bq/kg [13]. Another example is the cancellation of restrictions on the Pacific cod in Aomori Prefecture on October 31, 2012, the inspection results of which are shown in Figure 1-5. Since a reading of 130 Bq/kg emerged on August 9, 2012, the highest reading out of 78 inspected samples was 67 Bq/kg, with a median reading of 7.8 Bq/kg [14]. Another example is the cancellation of restrictions on the Pacific cod in the offshore area of Fukushima Prefecture on January 14, 2015, the inspection results of which are shown in Figure1-6. Since a reading of 110 Bq/kg emerged on June 20, 2013, the highest reading out of 235 inspected samples was 70 Bq/kg, with a median reading of 8.0 Bq/kg [15]. In this way, only when readings are confirmed to be consistently below limits are the restrictions on shipping and distribution canceled. It should be mentioned that restrictions on shipping and distribution were also lifted for Pacific cod in the offshore area of Fukushima Prefecture on February 24, 2015. Pacific cod is a species for which restrictions were applied over a broad area stretching from Aomori Prefecture to Ibaraki Prefecture following the accident. However, at the present time, these restrictions are lifted in all prefectures.

f Restrictions have also been lifted for landlocked salmon and whitespotted char in some water system in Fukushima prefecture.

Restriction enacted: May 30, 2012 n = 110 Restriction canceled: April 1, 2013

Figure 1

Figure 1-4 The Cancellation of Restrictions on the Olive Flounder, Miyagi Prefecture [13]

n = 78 Restriction enacted: August 27, 2012 Restriction canceled: October 31, 2012

Number of Pacific cods according to the amount of cesium detected

Figure 1-5 The Cancellation of Restrictions on the Pacific Cod, Aomori Prefecture [14]

140 Average 9.9 Bq/kg 120 Median 8.0 Bq/kg Standard Deviation 7.9Bq/kg

Number of samples n = 235 60 Restriction enacted: June 22, 2012 Restriction canceled: January 14, 2015 20

10 20 30 40 50 60 70 80 90 100 Radioactive Cesium (Bq/kg) Number of Pacific cods (Offshore) according to the amount of cesium detected (From Jun. 24th, 2013)

Figure 1-6 The Cancellation of Restrictions on the Pacific cod, Offshore Fukushima Prefecture [15]

As of March 31, 2016

Explanatory Fishing Suspension Distribution Restriction notes Fishing Suspension (Name for the Distribution Restriction (Name for the body of body of waters) Object fish waters) Object fish, Starting Date of Restriction

Distribution Restriction (Offshore Miyagi Pref.) Miyagi Prefecture Japanese black porgy: Jun. 28, 2012 ‐ (For the northers part, Nov. 6, 2012 ‐ )

Distribution Restriction (Offshore Fukushima Pref.)

Fat greenling, Red tongue sole, Japanese sandlance (adult, except for juvnile), Stone flounder, Goldeye rockfish, Surfperch, Brown hakeling, Fox jacopever, Black cow‐tongue, Black Fukushima Fishing Suspension Rockfish, Japanese black porgy, Ocellate spot skate, Cerry (Offshore Fukushima Pref.) salmon, Poacher, Rockfish (Sebastes cheni), Seabass, Starry All coastal and trawl fisheries (excluding trial operations and sales flounder, Slime flounder, Olive flounder, Spotted halibut, Conger as stated in the explanatory notes) Prefecture eel, Marbled flounder, Flathead, Brassblotched rockfish, Stimpson's hard clam: Jun. 22, 2012 – Long shanny, Barfin flounder: Jul. 12, 2012 – Scorpion fish: Aug. 8, 2013 ‐

Japanese sandlance (adult), Red tongue sole, Fox Northern jacopever, Black Rockfish, Japanese black porgy Area

Ibaraki Mid Japanese sandlance (adult), Rockfish (Sebastes ventricosus), Red stingray Prefecture Area

Southern Japanese sandlance (adult), Japanese scad, Fax jacopever Area

Note: There are trial fishing and sales for 73 species offshore Fukushima as below.

47 fish species: Greeneyes, Flathead flounder, Rosy seabass, Matsubara`s red rock fish, Ishikawa icefish, Black scraper, Striped jewfish, Dory, Redwing searobin, Greater amberjack, Monkfish, Thornhead, Japanese sandlance (juvenile), Southern mackerel, Finepatterned puffer, Roughscale sole, Halfbeak, Japanese Spanish mackerel, Vermiculated puffer, Japanese icefish, Whitebait (juvenile anchovy), Chum salmon, Alaska pollock, Sohachi flounder, Hairtail, Crimson sea bream, Tiger puffer, Flounder, Panther puffer, Blackfin flounder, Japanese amberjack, Gurnard, Starspotted smooth‐hound, Japanese jack mackerel, Japanese sardine, Littlemouth flounder, Chub mackerel, Red seabream, Pacific cod, John Dory, Globefish, Rikuzen flounder, Shotted halibut, Ridged‐eye flounder, Pacific barrelfish, Willowy flounder and Hilgendorf' saucord 8 crustaceam species: Swimming crab, Horsehair crab, Snow crab, Higoromo Shrimp, Sand crab, Red snow crab, Botan shrimp and Alaskan pink shrimp 7 squid and octopus species: Swordtip squid, Japanese dwarf squid, Japanese flying squid, Common octopus, Giant Pacific octopus, Chestnut octopus and Spear squid 9 shellfish species: Japanese littleneck clam, Abalone, Double sculptured Neptune, Japanese whelk, Surf clam, Paper whelk, Whelk (Neptunea constricta, Beringius polynematicus and Neptunea arthritica arthritica) 2 other species: Sea cucumber and Northern sea urchin

Figure 1-7 The State of Distribution Restrictions and Suspensions in Japan (as of March 31, 2016)

(Box 1) Calculation of the Limits for Human Consumption In the calculation of the limits for human consumption[10], the regulated radionuclide types were, among those released in the Fukushima Daiichi NPS accident, all of the radionuclides on the Nuclear and Industrial Safety Agency’s emissions trial calculation list that have a half-life of over one year (cesium-134, cesium-137, strontium-90, plutonium, ruthenium-106). The limits were not set for iodine, which has a short half-life, and uranium, which even at the site of the accident was detected in quantities comparable to naturally-occurring levels. Measurements of radionuclides other than radioactive cesium (plutonium, strontium-90, and ruthenium-106) are time-consuming. Therefore, the transfer factor of each type of radionuclide was analyzed for each transfer path, and the contribution rate of radioactive

cesium was calculated with respect to the food intake averages by sex, age group and food group. For land-made products, because the vast majority of contamination occurs through the intake of radionuclides from the soil, environment monitoring data (or, when there are no data available, the trail calculation values of the Nuclear and Industrial Safety Agency (NISA)) are used for initial cesium-137

concentration values in calculations. For marine products, because there is a great deal of variety in habitats and environment monitoring data is relatively limited compared to land-made products, assumptions are set to be safe with a wide margin of error. Hence, radionuclides other than radioactive cesium are assumed in marine products to have a contribution rate as high as 50 %.As a result, in the age group of over 19-year-old, for example, radiation dosage from non-cesium radionuclides in food is estimated on the large side at approximately 12 %. It was further assumed that 50 % of the food products sent to market were contaminated with radioactive materials at the maximum amount under the limit. Based on the above food intake amounts by age group as well as the contribution rate conversion factors of other radionuclides were taken into account to set the limits for radioactive cesium that would keep dosage below the annual dosage allotted to exposure from food (i.e., the annual dosage upper bound of 1mSv minus the aggregate dosage allotted to drinking 10 Bq/kg of water for a year [approx.0.1 mSv], resulting in an annual dosage from food of approx. 0.9 mSv). (The limit for food, minus drinking water) [in Bq/kg] ＝(The annual dosage allotted to food) [mSv/y] ÷ Σ(the total target-radionuclides dosage factor in each food classification*) [mSv/Bq] × (annual intake of each food product in each food classification) [kg/y] × (the proportion of items sent to market that are contaminated) *The total target-radionuclides dosage factor (mSv/Bq) is a coefficient that expresses the total dosage of regulated radionuclides (mSv) per 1 Bq of radioactive cesium (134+137) in food. This coefficient is calculated by calculating the amount of Bq of each radionuclide is contained in a food unit with 1 Bq of cesium, then multiplying each radionuclide type by the dosage coefficient and taking the sum of those values. The result was to set the limit for radioactive cesium in food at 100 Bq/kg, such that the limit would be considered safe for any age group, based on the most severe (smallest) limit value of all the ages and demographics, 120 Bq/kg for 13- to 18-year-old boys. It should be noted that the Ministry of Health, Labour and Welfare is conducting scientific research to verify the validity of limits in concentration measurements for radioactive cesium and other nuclides in food. Although it has yet to be concluded, none of the data studied thus far points to a need to reexamine limits.

Drinking water Of the 0.9 mSv, approximately 88% is considered to be the Food Approx. 0.9 mSv influence of cesium and the remaining 12% the influence of Approx. 0.1 radioactive materials other than cesium. mSv

(Box 2) Survey of Radiation Dose from Radionuclides in Foods Calculation of the Limits As outlined in box 1, inspections of foodstuff are conducted according to these limits applicable to foodstuff. The Ministry of Health, Labour and Welfare has conducted surveys to determine the actual extent to which people have been exposed to radioactivity from foodstuff as a result of shipping restrictions imposed on foodstuff found to exceed limits through these inspections. Two types of surveys have been carried out: (1) “market basket survey (MB survey)” and (2) “duplicate diet survey”. In the MB survey, “market basket samples” were prepared as national average portion of meal, using foods actually distributed in the market, and their radiation doses were measured. In the duplicate diet survey, duplicate portions of actual meals served in households were collected and mixed uniformly, and their radiation doses were measured. Ten surveys targeted radioactive cesium, and seven surveys targeted radioactive strontium and plutonium (as of March 2016) [16; 17; 18; 19; 20; 21; 22; 23; 24; 25;26;27;28;29]. In the first survey after the F1NPS accident carried out from September through November 2011, targeting Miyagi Prefecture, Fukushima Prefecture (Naka-dori) and Tokyo, the radiation doses from radioactive cesium (Cs-134 + Cs-137) in foods were estimated to be 0.0021 - 0.019 mSv/year. In the following surveys, the estimated doses have not exceeded 0.01 mSv/year, in all areas targeted in the surveys. In the latest MB survey (carried out in February and March 2015),exposure to radioactive cesium from foodstuff (Cs-134 + Cs-137) was between 0.0021 and 0.019 mSv/year according to the first surveys conducted after the accident between September and November 2011 (Miyagi Prefecture, Fukushima Prefecture (Nakadōri), and Tokyo). Subsequent surveys, however, revealed that exposure in all regions fell to 0.01 mSv/year or less. In the latest Market Basket Survey (carried out in February and March 2015), the estimated dose was 0.0020 mSv/year even in the region showing the highest value. These estimated doses were way far below 1mSv/year, the maximum permissible annual dose of radiation constituting the basis of the standard limits [29]. The same surveys also estimated annual doses from radioactive potassium (K-40) which naturally exists in foods. The results showed that estimated annual doses from radioactive cesium have been substantially lower than those from K-40 (0.14 - 0.22 mSv) [18; 21]. Moreover, the Market Basket Surveys targeting strontium-90 and plutonium (Pu-238, Pu-239+240) have been conducted a total of seven times in regions nationwide since 2012. While strontium-90 has been detected in certain samples, these levels have consistently fallen within the range of levels detected prior to the nuclear power plant accident. Plutonium has not been detected [19; 22; 24; 26; 28]. These results show that the management of radiation doses from foods has been functioning properly since the aftermath of F1NPS accident to today.

(Box 3) Examples of Local Government Monitoring Plan 1. Example of the Monitoring Plan for the 4th Quarter of FY2014 (January to March 2015) for Miyagi Prefecture) [30] ○Samples are secured in each sea zone and inspection

began. Inspection frequency is increased Sea zones: Divided into 7 sea zones if the detected level of ①Northern Coastal Zone Category # of radionuclides approach or exceed ②Central Coastal Zone (Food item inspected before items ③Sendai Bay North-Central Zone or at the time of distribution)

④Sendai Bay South Zone Freq. of # of cities ⑤Mt. Kinka North Offshore Zone inspection in which samples ⑥Mt. Kinka South Offshore Zone collected >1 a week ⑦Pacific Zone Marine fish 27 Entire pref. (whenever necessary)

>1 a week Inland fish 4 Entire pref. (whenever necessary)

Inspected items (that are marine fish

actually harvested in the planned period)

A. Items in which radioactive cesium of over 1/2 the limit has been detected Olive flounder, flatfish (2 groups), fat greenling, rockfish / scorpionfishes / marbled rockfishes (2 groups), sharks/ rays, Pacific cod, brown hakeling, gurnard / poacher, Japanese black porgy / flathead mullet, seabass, puffers, conger eels, flathead, Japanese

littleneck clam B. Major Items After Production Status Taken Into Account Horse mackerels, Alaskan pollock, monkfishes, croakers/drums/sailfin poachers, sea breams (except black porgy) / john dorys, surfperch, Japanese sandlance (adult), sea urchins, oriental weather loach, basses, Japanese sand lance (juvenile) / whitebait, icefishs, sardines, mackerels, amberjacks, Japanese gissus / greeneyes / jewfishes, hairtails, Japanese whiting, coho salmon, crustaceans, shellfish, seaweeds, squids / octopuses

2. Example of the Monitoring Plan for the 4th Quarter of FY2014 (January to March 2015) for Chiba Prefecture) [88] ○ Measurement at a rate of approx. 40 samples/week Habitat January February March Sardines, mackerels, Sardines, mackerels, Sardines, mackerels, Surface layer horse mackerels, horse mackerels horse mackerels halfbeak Japanese amberjack, Japanese amberjack, red Japanese amberjack, red Intermediate red seabream, seabass, seabream, seabass, seabream, seabass, layer Japanese black porgy, Japanese black porgy, Japanese black porgy hairtail hairtail Olive flounder, flounder Olive flounder, flounder Olive flounder, flounder Bottom layer family, rockfish family, family, rockfish family, family, rockfish family, scorpion fish, gurnard, scorpion fish, gurnard, scorpion fish, gurnard, alfonsino alfonsino alfonsino Japanese littleneck Japanese littleneck clam, Japanese littleneck clam, clam, common orient common orient clam, common orient clam, Shellfish clam, Chinese mactra Chinese mactra clam, Chinese mactra clam, clam, hard clam, clam hard clam, clam (Meretrix hard clam, clam (Meretrix (Meretrix lamarckii) lamarckii) lamarckii) Squids & Common octopus Spear squid octopuses Seaweeds Laver Laver Laver, hijiki seaweed Inland waters Omitted

Chapter 2. Results of Radioactive Cesium Inspections for Fishery Products As explained in Chapter 1, radioactive materials in fishery products have been monitored continuously since immediately after the Fukushima Daiichi NPS accident. Further, 2-1-1 below explains the detail of intake and emission of radioactive materials by fish and other fishery products, and shows that cesium concentration in fishery products drop as cesium concentrations in the environment drop. This chapter will show inspection results with respect to region, changes with time (time-series), trends in different major fish groups, and other topics. Inspection results for other fishery products not discussed in this chapter are collected in an appendix table at the end of this report. As has already been mentioned, inspections are in principle conducted at a stage prior to shipping. If an item is found to exceed 100 Bq/kg, the local government will issue a request to refrain from shipping fish of the same species as the aforementioned item to fishery operators engaging in fishery operations in the given area of the ocean. Where 100 Bq/kg readings extend across a regional area, the director-general of the nuclear emergency response headquarters will issue instructions to put shipping restrictions into force for the given area of the ocean and fish species. Inspection results as outlined in this chapter also include inspection results for items that are currently subject to shipping restrictions but do not mean that radioactive cesium exceeding 100 Bq/kg has been detected in fishery products that are being distributed.

About the graphs: ・ Histogram: Concentrations on the horizontal axis; on the vertical axis, each concentration’s relative frequency calculated year-by-year. Suitable for examining overall distribution of concentrations and the changes therein. ・ Scatter plot: Time on the horizontal axis; radioactive cesium concentration on the vertical axis. Suitable for examining the trends of radioactive cesium concentration over time. ・ Figures1-8 to 1-39have been drawn based on data from fishery product radioactive material inspections published by the Fisheries Agency [31].

1-2-1 Inspection Results for Nationwide Fishery Products in Japan (in total) Figure 1-8 displays cumulative totals of all inspection results for the whole country to the present date. Since the accident of Fukushima Daiichi NPS, inspections of 88,559 items have been conducted nation-wide up to the end of March 2016. Results showing levels no greater than 100 Bq/kg have been found in 85,574 items, which comprise 96.6% of all items inspected. In Fukushima Prefecture, 93.6 % (35,594 of 38,043) of samples were within100 Bq/kg. Outside of Fukushima Prefecture, the figure is 98.9% (49,980 of 50,516). Figure 1-9 displays aggregated inspection results by fiscal year. It is important to note that because the inspections focus on fish species and sea zones found in the previous year to contain high radioactivity values, the breakdown of each year is different and years cannot simply be compared to one another. However, in FY2015, the proportion of samples exceeding 100 Bq/kg has declined to 0.1%. Thus, with the passage of time, the proportion of results exceeding 100 Bq/kg has dropped, and also, the overall distribution of concentrations has shifted to lower level (i.e., shifting to the left in the graphs). This trend, as explained in 2-1-1, is considered to show that as radioactive cesium concentrations drop off in sea water that once produced high readings, radioactive cesium concentrations drop off in fishery products as well.

The details are described below. Although there are differences in levels of contamination and the rate at which readings drop off from fish species to species, the trends are the same for all of them.

(Samples) Other prefectures (50,516)

Fukushima (38,043)

More than 500

100 or less More than 500

Figure 1-8 Nationwide Fishery Products Inspection Results (in total) (Mar. 2011-Mar. 2016)

Nation wide Nation wide Nation wide Nation wide Nation wide (2013.4～2014.3) (2014.4～2015.3) (2015.4～2016.3) (2011.3～2012.3) (2012.4～2013.3)

Figure 1-9 Nationwide Fishery Products Inspection Results (in total) (by fiscal year) (The numbers in parentheses show number of samples)

1-2-2 Inspection Results for Fukushima Prefecture Fishery Products (all) Figure 1-10 displays the number of samples in Fukushima Prefecture inspections that exceeded 100 Bq/kg in 3-month periods, as well as its ratio relative to the total number of inspections (hereinafter, “excess ratio”) in that period. Figure 1-11 shows this same data displayed by fiscal year. In Fukushima Prefecture, 53.0 % of samples taken in the period immediately following the Fukushima Daiichi NPS accident (April – June 2011) were over 100 Bq/kg; however, in the single year after the accident, that proportion dropped by half. Since FY2012, the focus of inspection was shifted to the specific fish species that had ever been detected over 50 Bq/kg during one year after the accident. Nevertheless, the proportion of samples exceeding 100 Bq/kg continued to decline. In the period from January to March 2016, zero percent of samples yielded over 100 Bq/kg.

Coastal fishing and bottom trawling operations in the waters around Fukushima were subject to tardily subject to suspensions after the accident in March 2011. However, after thorough inspections, trial fishing and sales resumed in June 2012 for species that consistently demonstrated radionuclide levels below the limits, followed by gradual increase of target fish species and expansion of allowed fishing areas. Information on the species subject to trial fishing and sales, developments on allowed fishing areas and fishing methods, and the results of inspections performed during trial fishing and sales are all published on the Fukushima Prefectural Federation of Fisheries Co-operative Associations website.g

More than 100Bq/kg Total：38,043 samples (Samples) 100Bq/kg or less More than 100Bq/kg： 2,449 samples (Excess ratio) Excess ratio 100Bq/kg or less：35,594 samples

2011 2011 2011 2012 2012 2012 2012 2013 2013 2013 2013 2014 2014 2014 2014 2015 2015 2015 2015 2016 Apr‐Jun Jul‐Sep Oct‐Dec Jan‐MarApr ‐Jun Jul‐Sep Oct‐Dec Jan‐Mar Apr‐Jun Jul‐Sep Oct‐Dec Jan‐Mar Apr‐Jun Jul‐Sep Oct‐Dec Jan‐MarApr ‐Jun Jul‐Sep Oct‐Dec Jan‐Mar Figure 1-10 Inspection Results for Fukushima Prefecture Fishery Products (all) (>100 Bq/kg readings in 3-month periods)

Fukushima Fukushima Fukushima Fukushima Fukushima ～ (2011.3～2012.3) (2012.4～2013.3) (2013.4～2014.3) (2014.4～2015.3) (2015.4 2016.3)

Figure 1-11 Inspection Results for Fukushima Prefecture Fishery Products (all) (by fiscal year)

Figure 1-12 through Figure 1-15 show the number of Fukushima Prefecture samples exceeding readings of 100 Bq/kg and the excess ratio relative to the total number of samples, separated into marine and freshwater fish species, and aggregated in 3-month and fiscal year periods. For marine fish, as displayed in Figure 1-13, 64.8% of samples in FY2011 were within 100 Bq/kg. However concentrations declined in the passage of time, such that all samples taken since April 2015 have been yielding not higher than 100 Bq/kg. For freshwater fish, as displayed in Figure 1-15, 68.3% of samples were within 100 Bq/kg in FY2011, but by FY2015, 98.9% of results were within 100 Bq/kg. Although overall concentrations of radioactive cesium have decreased, the rate of decrease is slower than that of marine fish.

g Fukushima Prefectural Federation of Fisheries Co-operative Associations website http://www.jf-net.ne.jp/fsgyoren/

(Samples) (Excess ratio)

More than 100Bq/kg 100Bq/kg or less Excess ratio

2011 2011 2011 2012 2012 2012 2012 2013 2013 2013 2013 2014 2014 2014 2014 2015 2015 2015 2015 2016 Apr‐Jun Jul‐Sep Oct‐Dec Jan‐Mar Apr‐Jun Jul‐Sep Oct‐Dec Jan‐Mar Apr‐Jun Jul‐Sep Oct‐Dec Jan‐MarApr ‐Jun Jul‐Sep Oct‐Dec Jan‐MarApr ‐Jun Jul‐Sep Oct‐Dec Jan‐Mar Figure 1-12 Inspection Results for Fukushima Prefecture Marine Fish Species (>100 Bq/kg readings by 3-month periods)

Fukushima, marine species Fukushima, marine species Fukushima, marine species Fukushima, marine species Fukushima, marine species (2011.3～2012.3) (2012.4～2013.3) (2013.4～2014.3) (2014.4～2015.3) (2015.4～2016.3)

Figure 1-13 Inspection Results for Fukushima Prefecture Marine Fish Species (by fiscal year)

(Samples) (Excess ratio)

More than 100Bq/kg 100Bq/kg or less Excess ratio

2011 2011 2011 2012 2012 2012 2012 2013 2013 2013 2013 2014 2014 2014 2014 2015 2015 2015 2015 2016

Apr‐Jun Jul‐Sep Oct‐Dec Jan‐Mar Apr‐Jun Jul‐Sep Oct‐Dec Jan‐Mar Apr‐Jun Jul‐SepOct‐Dec Jan‐Mar Apr‐Jun Jul‐Sep Oct‐Dec Jan‐Mar Apr‐Jun Jul‐Sep Oct‐Dec Jan‐Mar Figure 1-14 Inspection Results for Fukushima Prefecture Freshwater Species (>100 Bq/kg readings, by 3-month periods)

Fukushima, freshwater Fukushima, freshwater Fukushima, freshwater Fukushima, freshwater Fukushima, freshwater (2011.3～2012.3) (2012.4～2013.3) (2013.4～2014.3) (2014.4～2015.3) (2015.4～2016.3)

Figure 1-15 Inspection Results for Fukushima Prefecture Freshwater Species (by fiscal year)

1-2-3 Inspection Results for Fishery Products (all) from Outside Fukushima Prefecture Figure 1-16 shows the number of non-Fukushima Prefecture samples exceeding readings of 100 Bq/kg and the excess ratio relative to the total number of samples, aggregated into 3-month periods. Figure 1-17shows the same data summed up by fiscal year. As Figure 1-16 demonstrates for areas outside of Fukushima Prefecture, even in the March to June 2011 period after the accident, 93.4 % of samples were within the 100 Bq/kg. This percentage of samples exceeding readings of 100 Bg/kg further declined with the passage of time, such that 99% of samples taken since the October to December 2012 period yielded readings of no more than 100 Bq/kg. Then, all samples taken in the January to March 2016 period yielded readings no higher than 100 Bq/kg. Figure 1-18 through Figure1- 21 show the number of non-Fukushima Prefecture samples exceeding readings of 100 Bq/kg and the excess ratio relative to the total number of samples, separated into marine and freshwater fish species, and aggregated in 3-month and fiscal year periods. According to Figures 1-19 and 1-21, a comparison of inspection results for FY2015 shows that all marine fish species (100%) and 99.6% of freshwater fish species were within 100 Bq/kg. Further examination of the proportion of FY2015 samples over 50 Bq/kg shows that, 0 % of marine fish samples were over 50 Bq/kg, 4.2 % of freshwater fish samples exceeded that mark. Hence, radioactive cesium concentrations were slightly higher in freshwater fish samples than in marine fish samples.

More than 100Bq/kg Total：50,516 samples 100Bq/kg or less More than 100Bq/kg： 536 samples (Samples) Excess ratio 100Bq/kg or less：49,980 samples (Excess ratio)

2011 2011 2011 2012 2012 2012 2012 2013 2013 2013 2013 2014 2014 2014 2014 2015 2015 2015 2015 2016 Apr‐Jun Jul‐Sep Oct‐Dec Jan‐Mar Apr‐Jun Jul‐Sep Oct‐Dec Jan‐Mar Apr‐Jun Jul‐Sep Oct‐Dec Jan‐Mar Apr‐Jun Jul‐Sep Oct‐Dec Jan‐Mar Apr‐Jun Jul‐Sep Oct‐Dec Jan‐Mar Figure 1-16 Inspection Results for Non-Fukushima Prefecture Fishery Products (all) (>100 Bq/kg readings, by 3-month periods)

Other prefectures Other prefectures Other prefectures Other prefectures Other prefectures ～ (2014.4～2015.3) (2015.4～2016.3) (2011.3～2012.3) (2012.4～2013.3) (2013.4 2014.3)

Figure 1-17 Inspection Results for Non-Fukushima Prefecture Fishery Products (all) (by fiscal year)

(Samples) (Excess ratio)

More than 100Bq/kg 100Bq/kg or less Excess ratio

2011 2011 2011 2012 2012 2012 2012 2013 2013 2013 2013 2014 2014 2014 2014 2015 2015 2015 2015 2016 Apr‐Jun Jan‐Mar Jul‐Sep Jul‐Sep Oct‐Dec Jan‐Mar Apr‐Jun Jul‐Sep Oct‐Dec Apr‐Jun Jul‐Sep Oct‐Dec Jan‐Mar Apr‐Jun Oct‐Dec Jan‐Mar Apr‐Jun Jul‐Sep Oct‐Dec Jan‐Mar Figure 1 -18 Inspection Results for Non-Fukushima Prefecture Marine Fish Species (>100 Bq/kg readings, by 3-month periods)

Other prefectures, marine Other prefectures, marine Other prefectures, marine Other prefectures, marine Other prefectures, marine species (2015.4～2016.3) ～ Species (2011.3～2012.3) species (2012.4～2013.3) species (2013.4～2014.3) species (2014.4 2015.3)

0％

Figure 1-19 Inspection Results for Non-Fukushima Prefecture Marine Fish Species (by fiscal year)

(Samples) (Excess ratio)

More than 100Bq/kg 100Bq/kg or less

2011 2011 2011 2012 2012 2012 2012 2013 2013 2013 2013 2014 2014 2014 2014 2015 2015 2015 2015 2016 Apr‐Jun Jul‐Sep Oct‐Dec Jan‐Mar Apr‐Jun Jul‐Sep Oct‐Dec Jan‐MarApr ‐Jun Jul‐Sep Oct‐Dec Jan‐Mar Apr‐Jun Jul‐Sep Oct‐DecJan ‐Mar Apr‐Jun Jul‐Sep Oct‐Dec Jan‐Mar

Figure 1-20 Inspection Results for Non-Fukushima Prefecture Freshwater Fish Species (>100 Bq/kg readings, by 3-month periods)

Other prefectures, freshwater Other prefectures, freshwater Other prefectures, freshwater Other prefectures, freshwater Other prefectures, freshwater ～ species (2011.3～2012.3) species (2012.4～2013.3) species (2013.4～2014.3) species (2014.4～2015.3) species (2015.4 2016.3)

4.2 %

Figure 1-21 Inspection Results for Non-Fukushima Prefecture Freshwater Fish Species (by fiscal year)

1-2-4 Trends within Fish Species Differences in radioactive cesium concentrations among various fish species and sea zones become apparent through monitoring. The feeding habit and living habitat type of each species is thought to be relevant to the difference. As the differences between marine and freshwater fish have already been explained, this section focuses on the differences among the main fish species.

(1) Surface-layer fish As shown in Figure1-22 (leftmost chart) and Figure1-23, there were samples of Japanese sandlance (juvenile) and whitebait (juvenile anchovy) in the immediate post-accident period that exceeded provisional regulation values of 500 Bq/kg, but the levels of radioactive cesium concentration quickly dropped off. Except for one sample of halfbeak harvested in February 2013 in the waters off Fukushima Prefecture, there have been no surface-layer fish since autumn 2011 with readings that exceeded 100 Bq/kg.

(2) Migratory fish Inspection results for saury and chum salmon, migratory fish species, are displayed in Figure 1-22 (center graph). The levels of radioactive cesium have never exceeded 100 Bq/kg. They have been within 50 Bq/kg. Samples for skipjack and other tuna species have also never exceeded 100 Bq/kg.

(3) Squid and octopus Inspection results for spear squid and north pacific giant octopus are displayed in Figure 1-22 (rightmost graph). There were some high readings immediately after the accident in 2011, but afterward there was a precipitous drop in radioactive cesium concentrations that was even more rapid than with surface-layer fish like Japanese sandlance and whitebait (juvenile anchovy). Today, no sample has been found to be beyond 50 Bq/kg. As with crustaceans and shellfish discussed later, salts are exchanged freely in and out of marine invertebrates’ bodies and the sea water. Therefore, it is thought that if radioactive cesium concentrations in the water drop, then concentrations inside marine invertebrates’ bodies will also quickly drop.

Surface‐layer fish Migratory fish Squid and octopus

Bq/kg Nationwide Japanese sandlance Bq/kg Nationwide Saury Bq/kg Nationwide Spear squid

Whitebait (juvenile anchovy) Chum salmon North pacific giant octopus

n = 1024 n = 1430 n = 1074

Figure 1-22 Inspection Results for Surface-layer Fish, Migratory Fish, Squid and Octopus

Figure 1-23 Nationwide Inspection Results for Surface-layer Fish (Japanese sandlance, Whitebait (juvenile anchovy)) (by fiscal year)

(4) Intermediate-layer fish (Chub mackerel and Southern mackerel) Figure 1-24 displays inspection results for chub mackerel and southern mackerel mainly caught offshore. None of the radioactive cesium readings exceed either the post-accident provisional regulation values of 500 Bq/kg (in place until year-end FY2011) or the limits of 100 Bq/kg (in place since FY2012). Moreover, no sample has been found to be beyond 50 Bq/kg since FY2012.

Figure 1-24 Nationwide Inspection Results for Chub mackerel and Southern mackerel (by fiscal year)

(Seabass) Monitoring of seabass living in coastal waters has been reinforced, as levels exceeding limits have been observed over a large area, there are great disparities in concentrations, and, while infrequent, cases of extremely high values have been observed.

Looking at inspections result for Fukushima, 57.4% percent of samples exceeded the limit in FY2011, then, concentrations of radioactive substances gradually declined, such that no samples yielded in excess of 100 Bq/kg in FY2015. Likewise, no samples yielded in excess of 100 Bq/kg in FY2015 in prefectures other than Fukushima. Previously, it had been thought that the high concentrations of cesium detected in seabass were due in part to their use of rivers and estuaries. However, the latest research has not found a clear relationship between cesium concentration and use of rivers. It is therefore thought that their use of rivers is not a factor in the high concentrations of cesium in seabass [32].

Fukushima, Seabass Fukushima, Seabass Fukushima, Seabass Fukushima, Seabass Fukushima, Seabass (2011.3～2012.3) (2012.4～2013.3) (2013.4～2014.3) (2014.4～2015.3) (2015.4～2016.3)

Other prefectures, Seabass Other prefectures, Seabass Other prefectures, Seabass Other prefectures, Seabass Other prefectures, Seabass (2011.3～2012.3) (2013.4～2014.3) (2012.4～2013.3) (2014.4～2015.3) (2015.4～2016.3)

Figure 1-25 Inspection Results for Seabass (by fiscal year)

(5) Crabs, Shrimp, and other Crustaceans Inspection results for horsehair crab, snow crab, and north pacific krill are displayed in Figure 1-26 (leftmost chart). Readings since the 2011 accident have not exceeded 100 Bq/kg, with absolutely no readings beyond 50 Bq/kg.

(6) Shellfish Inspection results for shellfish (Japanese littleneck clam/common orient clam, surf clam, and oysters) are displayed in Figure 1-26 (center graph) and Figure 1-27. There were some samples that exceeded provisional regulation values of 500 Bq/kg immediately following the 2011 accident, but since FY2012 all readings have been within 100 Bq/kg, with almost no readings beyond 50 Bq/kg.

(7) Seaweeds Inspection results for seaweed (wakame seaweed [raw and salted], laver [dry laver], and sea tangle [raw and salted]) are shown in Figure 1-26 (rightmost chart). Although there were some samples that exceeded provisional regulation values of 500 Bq/kg immediately following the 2011 accident, radioactive cesium concentrations rapidly dropped off, and there are no more readings beyond 50 Bq/kg since FY2013.

Nationwide Nationwide Seaweeds Crabs and Shrimp Nationwide Shellfish Bq/kg Bq/kg Bq/kg

Horsehair crab, Snow crab Japanese littleneck clam, Wakame seaweed Common orient clam (raw and salted) North Pacific krill Surf clam Laver (dry laver) Oysters Sea tangle (raw and

Figure 1-26 Inspection Results for Crabs, Shrimp, Shellfish and Seaweeds

Figure 1-27 Nationwide Inspection Results for Shellfish (Japanese littleneck clam, Common orient clam, Surf clam, Oysters, Abalones and Japanese whelk) (by fiscal year)

(8) Demersal fish After the accident, samples of demersal fish that live near the bottom of the ocean yielded readings exceeding the standard limits in Fukushima Prefecture, however, no samples yielded readings in excess of 100 Bq/kg in FY2015. The trends among bottom fish vary significantly among species; specifically: ・ From FY2011 to FY2012, slightly high concentrations were found across a wide area as seen with olive flounder (Figure 1-31) and Pacific cod (Figure 1-32).Since FY2013, however, concentrations declined significantly; ・ Most samples taken after the accident for species such as Alaska pollack (Figure 1-33) and red seabream (Figure 1-34) yielded readings of 50 Bq/kg or less. In FY2015, no samples yielded readings in excess of 100 Bq/kg across all demersal fish species.

(Flounder family) Flounders show different trends depending on whether they inhabit shallow bottom areas or deeper bottom areas. Figure 1-28 shows inspection results for shallow-bottom flounders that live at depths of less than 100 meters (marbled flounder and stone flounder). While inspections conducted by Fukushima Prefecture revealed that 56% of samples yielded readings in excess of 100 Bq/kg in FY2011, this percentage has declined with each passing year, such that no samples yielded readings in excess of 100 Bq/kg in FY2015. Overall

34 concentrations of radioactive cesium are also clearly falling. As for other prefectures, although 8.6 % of samples exceeded 100 Bq/kg in FY2011, absolutely no such samples have been observed since FY2013. Figure 1-29 shows inspection results for littlemouth flounder, which is a type of shallow-bottom flounder. Although the results for this species show a trend that resembles those of marbled flounder and stone flounder in Figure 1-28, no samples for littlemouth flounder that exceed 100 Bq/kg have been seen since FY2013 in Fukushima Prefecture and since FY2012 in other prefectures, thus demonstrating an early decline. Figure 1-30 shows inspection results for deep-bottom flounders that live at depths of 100 meters or more (flathead flounder, roughscale sole and willowy flounder). Since FY2012, all nationwide samples, including those for Fukushima Prefecture, have been within 100 Bq/kg and only very few have exceeded 50 Bq/kg.

(Shallow-bottom flounders）

Fukushima, Marbled flounder Fukushima, Marbled flounder Fukushima, Marbled flounder Fukushima, Marbled flounder Fukushima, Marbled flounder and Stone flounder and Stone flounder and Stone flounder and Stone flounder and Stone flounder (2015.4～2016.3) (2011.3～2012.3) (2012.4～2013.3) (2013.4～2014.3) (2014.4～2015.3)

Other prefectures, Marbled Other prefectures, Marbled Other prefectures, Marbled Other prefectures, Marbled Other prefectures, Marbled flounder and Stone flounder flounder and Stone flounder (2014.4 flounder and Stone flounder flounder and Stone flounder flounder and Stone flounder (2013.4～2014.3) ～2015.3) (2015.4～2016.3) (2011.3～2012.3) (2012.4～2013.3)

Figure 1-28 Inspection Results for Shallow-bottom Flounders (Marbled flounder and Stone flounder) (by fiscal year)

Fukushima, Fukushima, Fukushima, Fukushima, Fukushima, Littlemouth flounder Littlemouth flounder Littlemouth flounder Littlemouth flounder Littlemouth flounder (2011.3～2012.3) (2012.4～2013.3) (2013.4～2014.3) (2014.4～2015.3) (2015.4～2016.3)

Other prefectures, Other prefectures, Other prefectures, Other prefectures, Other prefectures, Littlemouth flounder Littlemouth flounder Littlemouth flounder Littlemouth flounder Littlemouth flounder (2011.3～2012.3)

Figure 1-29 Inspection Results for Littlemouth flounder (by fiscal year)

(Deep-bottom flounders)

Figure 1-30 Inspection Results for Deep-bottom Flounders (Flathead flounder, Roughscale sole and Willowy flounder) (by fiscal year)

(Olive flounder) Figure 1-31 shows inspection results for the olive flounder. Looking at the results for Fukushima Prefecture, 52.7% of samples exceeded the limit in FY2011 and 21.2 % exceeded it in FY2012. However, concentrations have significantly declined since FY2013, then, all samples yielded readings of no more than 100 Bq/kg since FY2014. Identical results were obtained outside of Fukushima Prefecture.

Fukushima, Olive flounder Fukushima, Olive flounder Fukushima, Olive flounder Fukushima, Olive flounder Fukushima, Olive flounder

Other prefectures, Other prefectures, Other prefectures, Other prefectures, Other prefectures, Olive flounder Olive flounder Olive flounder Olive flounder Olive flounder

Figure 1-31 Inspection Results for Olive flounder (by fiscal year)

(Pacific cod and Alaska pollack) Figure 1-32 displays the nationwide inspection results for pacific cod. Samples of Pacific cod actually exceeded the limits even outside of Fukushima Prefecture, producing high readings in a comparatively broad range of locations. This is thought to be because Pacific cod has a period in which it approaches relatively highly contaminated coastal areas, and then in migratory period, it travels comparatively long distances [33]. Today, concentrations of radioactive cesium have remarkably dropped off. Whereas 13.0 % of samples exceeded 100 Bq/kg in FY2011, all samples were within 100 Bq/kg in FY2014, with no readings beyond 50 Bq/kg.

Figure 1-32 Nationwide Inspection Results for Pacific cod (by fiscal year)

Figure 1-33 shows the nationwide inspection results for Alaska pollack. Although it is in the same gadid family as Pacific cod, it displays a different trend. Except for one Alaska pollack sample off the coast of Fukushima in FY2012 which was found to have a reading of over 100 Bq/kg, no samples yielding readings in excess of 100 Bq/kg have been found since FY2011.

Figure 1-33 Nationwide Inspection Results for Alaska pollock (by fiscal year)

(Red seabream) Figure 1-34 shows the nationwide inspection results for red seabream. There have been no readings in excess of 100 Bq/kg since the accident, and FY2013 saw absolutely no readings within 50 Bq/kg.

Figure 1-34 Nationwide Inspection Results for Red seabream

(Rockfish family) Figure 1-35 shows the inspection results for the rockfish family (goldeye rockfish, rockfish (Sebastes cheni) and fox jacopever). In Fukushima Prefecture, 78.2 % of samples in FY2011 exceeded 100 Bq/kg, and high concentration levels were observed across the board. Subsequently, concentration levels have been declining gradually with the passage of time. No samples yielding readings in excess of 100 Bq/kg were obtained in FY2015. Particularly in the case of rockfish(Sebastes cheni), initially high contamination and the species’ low mobility are thought to have been behind the observance of samples with high values exceeding the limit even in 2014; however, further investigation into the cause is required. As for the other prefectures, the inspection results show that 16.7 % of samples exceeded 100 Bq/kg in FY2011; however, this percentage fell to 1.3 % in

FY2012. All samples have been within 100 Bq/kg from FY2013 onward.

Fukushima, Goldeye rockfish, Fukushima, Goldeye rockfish, Fukushima, Goldeye rockfish, Fukushima, Goldeye rockfish, Fukushima, Goldeye rockfish, Rockfish and Fox jacopever Rockfish and Fox jacopever Rockfish and Fox jacopever Rockfish and Fox jacopever Rockfish and Fox jacopever (2011.4～2012.3) (2012.4～2013.3) (2013.4～2014.3)

Other prefectures, Goldeye Other prefectures, Goldeye Other prefectures, Goldeye Other prefectures, Goldeye Other prefectures, Goldeye rockfish, Rockfish and Fox rockfish, Rockfish and Fox rockfish, Rockfish and Fox rockfish, Rockfish and Fox rockfish, Rockfish and Fox jacopever (2015.4～2016..3) jacopever (2011.3～2012.3) jacopever (2012.4～2013.3) jacopever (2013.4～2014.3) jacopever (2014.4～2015..3)

Figure 1-35 Inspection Results for the Rockfish Family (Goldeye rockfish, Rockfish (Sebastes cheni) and Fox jacopever) (by fiscal year)

(9) Freshwater fish Figure 1-36 shows inspection results for wild whitespotted char and wild land-locked salmon. In Fukushima Prefecture, 51.3% of samples yielded readings in excess of 100 Bq/kg in FY2011. Subsequently, concentration levels steadily declined with the passage of time, such that 2% of samples yielded readings in excess of 100 Bq/kg in FY2015. While samples yielding readings in excess of 100 Bq/kg continue to be found, concentrations of radioactive cesium are steadily declining. As for the other prefectures, the inspection results show that 24.1% of samples yielded reading in excess of 100 Bq/kg in FY2011; however the percentage has subsequently fallen to an extremely low, 0.3% in FY2015.

Fukushima, Whitespotted char Fukushima, Whitespotted char Fukushima, Whitespotted char Fukushima, Whitespotted char Fukushima, Whitespotted char (wild) and Land‐locked salmon (wild) and Land‐locked salmon (wild) and Land‐locked salmon (wild) and Land‐locked salmon (wild) and Land‐locked salmon (wild) (2015.4～2016.3) ～ (wild) (2014.4～2015.3) (wild) (2011.3～2012.3) (wild) (2012.4 2013.3) (wild) (2013.4～2014.3)

Other prefectures, Whitespotted Other prefectures, Whitespotted Other prefectures, Whitespotted Other prefectures, Whitespotted Other prefectures, Whitespotted ‐ char (wild) and Land‐locked salmon char (wild) and Land‐locked salmon ‐ char (wild) and Land locked salmon char (wild) and Land‐locked salmon char (wild) and Land locked salmon ～～ (wild(2014.4～2015.3) (wild(2015.4 2016.3) (wild) (2011.3～2012.3) (wild) (2012.4 2013.3) (wild) (2013.4～2014.3)

Figure 1-36 Inspection Results for Whitespotted char (wild) and Landlocked salmon (wild) (by fiscal year)

1-2-5 Inspection Results for Main Target Fish Species of Fishing and Farming by Fiscal Year Figure 1-37 outlines the results of yearly inspections conducted with respect to key fish species in the Pacific Ocean off the coast of eastern Japan, species subject to aquaculture, and fish species associated with relatively high export volumes (including species that were heavily exported prior to the disaster). The fish species mentioned here include some that had readings exceeding 100 Bq/kg immediately following the accident; however, those readings have currently fallen. Further, it is evident that many species have not posed a problem since the early days following the accident. It should be noted that some of the graphs provided in 1-2-4 have been reprinted here in the interest of showing trends of the main fish species together.

Surface layer

Intermediate layer

Bottom layer

Migratory fish

Total Total

Main target species for farming in the Pacific Ocean off of eastern Japan

2011.3~2012.3 N=4 2011.3~2012.3 N=11 2011.3~2012.3 N=13 2012.4~2013.3 N=3 2012.4~2013.3 N=56 2012.4~2013.3 N=26 2013.4~2014.3 N=8 2013.4~2014.3 N=20 2013.4~2014.3 N=157 2014.4~2015.3 N=174 2014.4~2015.3 N=170 2014.4~2015.3 N=345 2015.4~2016.3 N=189 2015.4~2016.3 N=163 2015.4~2016.3 N=325 Total N=378 Total N=420 (~50Bq/kg (1)) Total N=461

Squids, Octopuses and Shellfish

Crustaceans

Freshwater fish All samples of farmed whitespotted char and landlocked salmon yielded readings of 100 Bq/kg or less.

Figure 1-37 Inspection results for Main Target Species of Fishing and Farming (by fiscal year)

1-2-6 Concentrations of Radioactive Material in Marine Fish within 20-kilometer Radius of the Fukushima Daiichi NPS Absolutely no fishing activity is taking place within the port of the Fukushima Daiichi NPS and within an area extending out 20 km from the station and no marine organisms that inhabit these areas are being shipped or distributed to markets. Since April 2012, TEPCO has been monitoring marine fish species within 20-km radius of the station and releasing the results [34]. Figure 1-38 presents results released by TEPCO that have been tabulated for individual years. Grasping detailed by-species trends is difficult due to the limited number of samples. However, 35.8 % of samples exceeded 100 Bq/kg in FY2012. This percentage stood at 14 % in FY2013, 1.4 % in FY2014, and 0.3% in FY2015.Thus, concentrations of radioactive cesium in marine fish species are steadily decreasing with the passage of time, although at a rate that is slower than other marine areas. It can be seen that the percentage of samples exceeding 100 Bq/kg in FY2015 is extremely small.

Fish within 20 km of the NPS Fish within 20 km of the NPS Fish within 20 km of the NPS Fish within 20 km of the NPS (2012.4～2013.3) (2013.4～2014.3) (2014.4～2015.3) (2015.4～2016.3)

Figure 1-38 Changes in Radioactive Cesium Concentrations in Marine Fish Sampled within 20 km of Radius the Fukushima Daiichi NPS (Prepared by the Fisheries Agency based on materials released by TEPCO)

(Box 4) Fukushima Fishing Trials

Coastal fishing and bottom trawling operations in the waters around Fukushima prefecture were subject to voluntary suspensions after the accident in March 2011. However, after thorough inspections, trial fishing and sales resumed in June 2012 for species that consistently demonstrated radionuclide levels below the limits. While trial operations were temporarily suspended after leakage of contaminated TEPCO water was reported in the news in July 2013, seawater inspections conducted by Fukushima Prefecture revealed that concentrations of radioactive cesium and total beta radiation doses were approximately the same as they were before the accident occurred and that there were no differences in terms of inspection results for fishery products from around the time of the news reports on contaminated water leakage. Therefore, trial operations were resumed on September 25, 2013. At the present time, Fukushima Prefecture is conducting monitoring surveys for radioactive cesium that involve taking 180 samples per week (i.e., thorough examination using a germanium semiconductor detector for all target species of fishing activity, including those for which restrictions on shipping and distribution apply). At the same time, with an eye to future sales, the prefecture is considering expanding sea areas and species for trial fishing and sales as it conducts screening surveys to confirm the safety of fishery products as an independent initiative by the prefecture and the Fukushima Prefectural Federation of Fisheries Co-operative Associations.

Trial fishing areas Trial operations have been conducted off the coast of Fukushima Prefecture, outside a 20-kilometer radius of the Fukushima Daiichi Soma‐Haragama regional Nuclear Power Station. wholesale market

◆Bottom trawling operations were limited to offshore areas in order to minimize bycatches of the species other than those subject to the trial operations. Onahama fish ◆Operations have been carried out based on the content of licenses pertaining to market each fishing method and the rules governing fishery rights.

Fish species subject to trial operations (as of March 31, 2016)

47 fish species: greeneyes, flathead flounder, rosy seabass,Matsubara’s red roch fish, Ishikawa icefish, black scrape, striped jewfish, dory, redwing searobin, greater amberjack, monkfish, thornhead, Japanese sandlance (juvenile), southern mackerel, finepatterned puffer, roughscale sole, halfbeak, Japanese Spanish mackerel, vermiculated puffer, Japanese icefish, whitebait (juvenile anchovy), chum salmon, Alaska Pollock, Souhachi flounder,hairtail, crimson sea bream, tiger puffer, flounder (Pleuronichthys japonicas), panther puffer, blackfin flounder,Japanese amberjack, gurnard,straspotted smooth-hound, Japanese jack mackerel, Japanese sardine, littlemouth flounder, chub mackerel, red seabream, Pacific cod, John Dory, globefish, Rikuzen flounder, shotted halibut, ridged-eye flounder, Pacific barrelfish, willowy flounder,and Hilgendorf saucord 8 crustacean species: swimming crab, horsehair crab, snow crab, higoromo Shrimp, sand crab, red snow crab, botan shrimp and Alaskan pink shrimp 7 squid and octopus species: swordtip squid, Japanese dwarf squid, Japanese flying squid, common octopus, giant Pacific octopus, chestnut octopus and spear squid 9 shellfish species: Japanese littleneck clam, abalone, double sculptured neptune, Japanese whelk, surf clam, paper whelk, whelks (Neptunea constricta, Beringius polynematicus and Neptunea arthritica arthritica) Other 2 species: sea cucumber and northern sea urchin

1-2-7 Screening Test by Prefectural and Municipal Governments Prefectural and municipal governments conduct screening test apart from the inspections prescribed by the Guidelines. This screening test uses inspection equipment (NaI scintillation spectrometer) set up in a location like the marketplace and covers a substantial number of samples (Table 1-3). Except for one hilgendorf saucord caught in February 2014 during trial fishing in Fukushima, all samples inspected via these processes have been below the limits. These results act to support the credibility of the overall monitoring regime carried out by the prefectures. Coastal fishing and bottom trawling operations in the waters around Fukushima were subject to suspensions after the accident in March 2011. However, after thorough inspections, trial fishing and sales resumed in June 2012 for species that consistently demonstrated radionuclide levels within 100 Bq/kg, followed by gradual expansion of target fish species and allowed fishing areas. Information on the species subject to trial fishing and sales, developments on allowed fishing areas and fishing methods, and the results of inspections performed during trial fishing and sales are all published on the Fukushima Prefectural Federation of Fisheries Co-operative Associations websiteh.

Table 1-3 Screening Test by Prefectural and Municipal Governments

Ownership of Number of readings Prefecture the inspection Installation siteApr. 2013 - Apr. 2014 - Apr. 2015 - Target species machinery Mar. 2014 Mar. 2015 Mar. 2016 Chub mackerel, southern Hachinohe City Hachinohe Fish Market 238 281 280 mackerel, pacific cod, sardine National Food Research Institute (Hachinohe City) Aomori Brand Research Center Aomori Japanese scallop, hen clam (Mutsu City) Aomori Pref. 108 35 19 and other shellfish, seaweeds Agriculture and Forestry Research and sea water etc. Center Agricultural Produce Processing Research Center Kesennuma Fish Market Pacific cod, oliver flounder and Minami-sanriku Town Fish Market other species with lifted Miyagi Miyagi Pref.Onagawa Fish Market 7,961 5,955 5,404 restrictions, fish in season and Ishinomaki Fish Market fish from before the opening of Shiogama Fish Market the fishing season Soma Haragama Wholesale Market Fish species caught during Fukushima Fukushima Pref. 803 1,912 3,167 Onahama Fish Market fishing trials Ibaraki Prefectural Fisheries Whitebait, anchovy, Japanese Ibaraki Pref. 105 69 47 Experimental Station sandlance (juvenile), etc. Ibaraki Sea bream, flounders and Kita-Ibaraki City Otsu Fishery Port - 293 413 other often-caught species Chiba Prefectural Fisheries Research Sardines, Japanese jack Agency mackerel, seabass、mackerels Chiba Pref. 288 152 61 and other species major to the 〃（Choshi office） prefecture Chiba Sardines, mackerels, Choshi Fisheries Cooperative Japanese jack mackerel, Choshi City 531 290 243 Association Japanese amberjack, saury and other often-caught species

h Fukushima Prefectural Federation of Fisheries Co-operative Associations website http://www.jf-net.ne.jp/fsgyoren/

Chapter 3. Inspection for Radionuclides Other Than Radioactive Cesium

Apart from local governments’ monitoring of fishery products for radioactive cesium, the Fisheries Agency and the Japan Fisheries Research and Education Agency have been testing for radioactive strontium and plutonium since the accident. Additionally, in FY2014, the Ministry of Agriculture, Forestry and Fisheries conducted inspections of some of the radionuclides listed in the Codex Alimentarius Commission’s guidelines on radioactive material in foods [9]. This chapter describes the results of these efforts.

1-3-1 Inspections for Radioactive Strontium etc. by the Japan Fisheries Research and Education Agency From the time of the accident until the end of March 2016, the Fisheries Agency and the Japan Fisheries Research and Education Agency have announced the results of inspections they conducted for radioactive strontium (104 samples), plutonium (18 samples), and americium-241 (13 samples) that targeted a broad variety of fish species, including mackerel and Alaska pollock (Table1-4). These samples were harvested from all of the representative sea zones around Japan (Figure 1-39). Monitoring of radioactive materials in fishery products date back to March 1954, when the Daigo Fukuryu Maru fishing vessel was exposed to radiation from nuclear weapons testing. This prompted the Fisheries Agency to begin conducting the survey. Other surveys include the monitoring of land and waters surrounding nuclear power facilities by relevant local governments and others since before the Fukushima Daiichi NPS accident. The historical data on radioactivity levels in the environment which include these and other studies undertaken with the cooperation of relevant ministries, prefectural governments, and others are stored in the Nuclear Regulation Authority’s Environmental Radiation Database. According to this database, up through the period of 2000-2010 prior to the Fukushima Daiichi NPS accident, in the fish, shellfish and algae in the sea zones around Japan contained strontium-90 in concentrations between 0.26 Bq/kg and below the detection limit. With respect to the results of inspections concerning radioactive strontium conducted after the accident occurred, concentrations of strontium-90 and strontium-89 in all samples – with the exception of samples in which strontium with a level of radioactivity slightly higher than before the accident occurred was detected – were found to range between below measurable limits and 0.21 Bq/kg and below measurable limits, respectively, in the rockfish, Sebastes cheni (Cs-134 + Cs-137: 970 Bq/kg; Sr-89: 0.45 Bq/kg; Sr-90: 1.2 Bq/kg), the icefish (Cs-134 + Cs-137: 47 Bq/kg; Sr-90: 0.40 Bq/kg), and the marbled sole (Cs-134 + Cs-137: 4.0 Bq/kg; Sr-90: 0.41 Bq/kg), which had previously contained high concentrations of radioactive cesium; these results were approximately on par with concentrations measured prior to the accident.. Referring back to the database, it provides data that shows that up through the period of 2000-2010 prior to the Fukushima Daiichi NPS accident, the fish and shellfish in the sea zones around Japan contained plutonium-238 in concentrations between 0.0016 Bq/kg and below the minimum detectable level. And, plutonium-239+plutonium-240 concentrations were detected between 0.073 Bq/kg and below the detectable level. Looking at the results for plutonium following the accident, the levels were around the same as pre-accident levels, with all samples being below the detection limit in the case of plutonium-238 and between 0.0022

Bq/kg and below the detection limit for plutonium-239+ plutonium-240. Additionally, looking at levels of americium-241, data for fishery products prior to the accident at the Fukushima Daiichi NPS are extremely scarce. However, it is reported in the literature [35] that shellfish (clams (Meretrix lamarckii, Gomphina melanegis) and Ezo abalone) sampled off the coast of Ibaraki (between Tokai Village and Oarai) had levels between 0.00048 and 0.0046 Bq/kg. As for the results of inspections for americium-241 following the accident, samples had levels between 0.0015 Bq/kg and below the detection limit, which is close to the pre-accident range cited in the literature. As stated in Box 1, the maximum limits for food have been set to ensure that exposure does not exceed approximately 0.9 mSv per year, a figure that was arrived at by subtracting approximately 0.1 mSv, which is the level of exposure one can expect to obtain from potable water, from the maximum allowable radiation dosage per year of 1 mSv. It is assumed that dosage from radioactive materials other than radioactive cesium will equal approximately 12% (equivalent to approximately 0.11 mSv) of the dosage included in foodstuff overall (approximately 0.9 mSv). If we take a look at results for strontium-90 in post-accident fishery products (in particular, fish species) (Table 1-4), we see that strontium-90 was generally not detected. Even when detected, however, concentrations ranged from 0.015 to 1.2 Bq/kg. the daily amount of food ingested by an adult male estimate for 2.1 kg, and if the strontium-90 concentration of the food is equal to that of the rockfish, the icefish, and the marbled sole, therefore, the annual effective dose of strontium-90 in the food is estimated to be between 0.0086 and 0.026 mSv(Table 1-5). Dosages from plutonium and ruthenium are presumed to be at considerably low levels given the amount emitted by the nuclear power plant and the concentrations found in surrounding seawater, such that they can effectively be ignored [36]. Therefore, the concentrations of radionuclides in these marine fishery products are not substantial enough to be problematic.

Table 1-4 Inspection Results for Radioactive Strontium in Fishery Products (1 of 3)

Test Result (Unit: Bq/kg）

NO Species Sampling date Publication date Sr-89 Sr-90 Cs-134 Cs-137 I-131 Pt-238 Pt-239+240 Am-241 Ref. (analyzed part)

Japanese sardine N.D. Sr: Whole body 1 (Sardinops April 6, 2011 June 28, 2011 - 4.4 4.1 4.9 - - - (Detection limit: 0.04) Cs & I : muscle melanostictus)

Japanese sandlance N.D. Sr: Whole body 2 April 8, 2011 June 28, 2011 - 38 43 598 - - - (Ammodytes personatus) (Detection limit: 0.02) Cs & I : muscle

Japanese sandlance N.D. Sr: Whole body 3 April 12, 2011 June 28, 2011 - 33 33 397 - - - (Ammodytes personatus) (Detection limit: 0.03) Cs & I : muscle

Anchovy N.D. Sr: Whole body 4 April 14, 2011 June 28, 2011 - 3.84.1N.D.--- (Engraulis japonicus) (Detection limit: 0.04) Cs & I : muscle

Pacific cod N.D. 0.03 Sr: Whole body 5 April 21, 2011 August 30, 2011 16 18 N.D. - - - (Gadus macrocephalus) (Detection limit: 0.04) (Detection limit: 0.03) Cs & I : muscle

Flathead flounder N.D. N.D. Sr: Whole body 6 April 22, 2011 August 30, 2011 1.51.8N.D.--- (Hippoglossoides dubius) (Detection limit: 0.03) (Detection limit: 0.03) Cs & I : muscle

Swimming crab N.D. N.D. Sr: Whole body 7 (Portunus May 26, 2011 August 30, 2011 7.2 10.0 N.D. - - - (Detection limit: 0.03) (Detection limit: 0.03) Cs & I : muscle trituberculatus) Japanese sardine N.D. N.D. Sr: Whole body 8 (Sardinops June 22, 2011 August 30, 2011 8.2 11.0 N.D. - - - (Detection limit: 0.03) (Detection limit: 0.03) Cs & I : muscle melanostictus)

Southern mackerel N.D. N.D. Sr: Whole body 9 July 1, 2011 August 30, 2011 1.13.4N.D.--- (Scomber australasicus) (Detection limit: 0.04) (Detection limit: 0.03) Cs & I : muscle

Rockfish Sr: Whole body 10 December 21, 2011 March 9, 2012 0.45 1.2 390 580 N.D. - - - (Sebastes cheni) Cs & I : muscle

Shotted halibut N.D. Sr: Whole body 11 December 21, 2011 March 9, 2012 0.094 16 24 N.D. - - - (Eopsetta grigorjewi ) (Detection limit: 0.05) Cs & I : muscle

Southern mackerel N.D. Sr: Whole body 12 December 21, 2011 March 9, 2012 0.03 2.9 4.2 N.D. - - - (Scomber australasicus) (Detection limit: 0.04) Cs & I : muscle

Ishikawa icefish N.D. Sr & Cs: 13 (Salangichthys January 18, 2012 May 10, 2012 0.41829N.D.--- (Detection limit: 0.09) Whole body ishikawae) N.D. Rockfish Sr: Whole body 14 June 26, 2012 November 15, 2012 - (Detection limit: 18 33 N.D. - - - (Sebastes cheni) Cs & I : muscle 0.036) Alaska pollock N.D. Sr & Cs: 15 (Theragra August 1, 2012 November 15, 2012 - (Detection limit: 0.17 0.38 N.D. - - - Whole body chalcogramma) 0.025) N.D. Pacific saury Sr & Cs: 16 June 24, 2012 November 15, 2012 - (Detection limit: 0.44 0.78 N.D. - - - (Cololabis saira) Whole body 0.016) N.D. Chub mackerel Sr & Cs: 17 October 28, 2011 November 15, 2012 - (Detection limit: 11 15 N.D. - - - (Scomber japonicus) Whole body 0.025) 0.043 Conger eel Sr & Cs: 18 December 21, 2011 August 1, 2013 - (Detection limit: 8.713N.D.--- (Conger myriaster) Whole body 0.020) N.D. Southern mackerel Sr & Cs: 19 February 1, 2012 August 1, 2013 - (Detection limit: 0.73 1.1 N.D. - - - (Scomber australasicus) Whole body 0.015） N.D. Sakura shrimp Sr & Cs: 20 November 18, 2011 August 1, 2013 - (Detection limit: 0.047 0.096 N.D. - - - （Sergia lucens） Whole body 0.019） Black scraper N.D. Sr & Cs: 21 (Thamnaconus February 19, 2012 August 1, 2013 - (Detection limit: 2.23.1N.D.--- Whole body modestus) 0.023） Blunthead puffer N.D. Sr & Cs: 22 (Sphoeroides February 21, 2012 August 1, 2013 - (Detection limit: 0.91 1.1 N.D. - - - Whole body pachygaster) 0.013） N.D. Southern mackerel Sr & Cs: 23 August 29, 2012 August 1, 2013 - (Detection limit: 0.18 0.45 N.D. - - - (Scomber australasicus) Whole body 0.013） Japanese sardine N.D. Sr & Cs: 24 (Sardinops August 20, 2012 August 1, 2013 - (Detection limit: 0.18 0.39 N.D. - - - Whole body melanostictus) 0.013） N.D. Mahi-mahi SrSr & & Cs Cs: 25 September 3, 2012 August 1, 2013 - (Detection limit: 0.14 0.29 N.D. - - - (Coryphaena hippurus) MuscleWhole andexcept viscera edible part 0.029） Swimming crab N.D. N.D. N.D. Sr & Cs: 26 (Portunus September 2, 2012 August 1, 2013 - (Detection limit: (Detection limit: (Detection limit: N.D.--- Whole body trituberculatus) 0.018） 0.029） 0.043） N.D. Japanese jack mackerel Sr & Cs: 27 August 29, 2012 August 1, 2013 - (Detection limit: 0.45 0.94 N.D. - - - (Trachurus japonicas) Whole body 0.018） N.D. N.D. Round herring Sr & Cs: 28 September 2, 2012 August 1, 2013 - (Detection limit: (Detection limit: 0.10 N.D. - - - (Etrumeus teres) Whole body 0.018） 0.032） N.D. N.D. Chum salmon Sr & Cs: 29 November 1, 2012 August 1, 2013 - (Detection limit: (Detection limit: 0.13 N.D. - - - (Oncorhynchus keta) Whole body 0.018） 0.030） Scallop N.D. N.D. Sr & Cs: 30 (Mizuhopecten November 8, 2012 August 1, 2013 - (Detection limit: (Detection limit: 0.048 N.D. - - - Whole except shell yessoensis) 0.013） 0.021） N.D. Southern mackerel Sr & Cs: 31 October 16, 2012 August 1, 2013 - (Detection limit: 0.14 0.34 N.D. - - - (Scomber australasicus) Whole body 0.017） N.D. Chub mackerel Sr & Cs: 32 December 12, 2012 August 1, 2013 - (Detection limit: 0.12 0.29 N.D. - - - (Scomber japonicus) Whole body 0.017） N.D. Black rockfish SrSr & & Cs Cs: 33 November 5, 2012 August 1, 2013 - (Detection limit: 0.79 1.6 N.D. - - - (Sebastes schlegeli) MuscleWhole andexcept viscera edible part 0.032） N.D. Steller's sculpin Sr & Cs: 34 November 9, 2012 August 1, 2013 - (Detection limit: 0.40 0.71 N.D. - - - Sr & Cs (Myoxocephalus stelleri) Whole except edible part 0.029） Muscle and viscera Neon Flying Squid N.D. Sr & Cs: 35 (Ommastrephes June 4, 2012 August 1, 2013 - (Detection limit: 0.050 0.15 N.D. - - - Muscle part bartramii) 0.011）

Table 1-4 Inspection Results for Radioactive Strontium in Fishery Products (cont.)

Test Result (Unit: Bq/kg）

NO Species Sampling date Publication date Sr-89 Sr-90 Cs-134 Cs-137 I-131 Pt-238 Pt-239+240 Am-241 Ref. (analyzed part)

N.D. Alfonsino SrSr & CsCs: 36 October 17, 2012 August 1, 2013 - (Detection limit: 0.49 1.1 N.D. - - - (Beryx splendens) WholeMuscle exceptand viscera edible part 0.023） Pacific granadier N.D. SrSr & & Cs Cs: 37 (Coryphaenoides August 6, 2012 August 1, 2013 - (Detection limit: 0.23 0.44 N.D. - - - MuscleWhole andexcept viscera edible part acrolepis) 0.028） N.D. Giant Pacific octopus Sr & Cs: 38 July 21, 2012 August 1, 2013 - (Detection limit: 0.040 0.094 N.D. - - - (Paroctopus dofleini) Muscle part 0.016） N.D. N.D. Flounder Sr & & Cs Cs: 39 November 5, 2012 August 1, 2013 - (Detection limit: (Detection limit: 0.12 N.D. - - - (Pleuronectes obscures) MuscleWhole andexcept viscera edible part 0.022） 0.055） N.D. N.D. Flame snapper SrSr & & Cs Cs: 40 November 15, 2012 August 1, 2013 - (Detection limit: (Detection limit: 0.096 N.D. - - - (Etelis coruscans) MuscleWhole andexcept viscera edible part 0.023） 0.060） Alaska pollock N.D. N.D. Sr & Cs: 41 (Theragra October 28, 2012 October 25, 2013 (Detection limit: (Detection limit: 0.029 0.11 N.D. - - - Whole except viscera chalcogramma) 0.039） 0.016） Alaska pollock N.D. N.D. Sr & Cs: 42 (Theragra January 22, 2013 October 25, 2013 (Detection limit: (Detection limit: 0.030 0.13 N.D. - - - Whole except viscera chalcogramma) 0.081） 0.014） Alaska pollock N.D. N.D. Sr & Cs: 43 (Theragra February 15, 2013 October 25, 2013 (Detection limit: (Detection limit: 0.022 0.11 N.D. - - - Whole except viscera chalcogramma) 0.11） 0.018） Alaska pollock N.D. N.D. Sr & Cs: 44 (Theragra September 19, 2013 November 26, 2013 (Detection limit: 0.058 0.19 N.D. - - - (Detection limit: 0.12) Whole body chalcogramma) 0.015） Alaska pollock N.D. N.D. Sr & Cs: 45 (Theragra September 19, 2013 November 26, 2013 (Detection limit: (Detection limit: 0.032 0.16 N.D. - - - Whole body chalcogramma) 0.059） 0.014） Alaska pollock N.D. N.D. Sr & Cs: 46 (Theragra October 2, 2013 November 26, 2013 (Detection limit: (Detection limit: 0.036 0.16 N.D. - - - Whole body chalcogramma) 0.034） 0.013） Alaska pollock N.D. N.D. Sr & Cs: 47 (Theragra October 2, 2013 November 26, 2013 (Detection limit: (Detection limit: 0.031 0.094 N.D. - - - Whole body chalcogramma) 0.094） 0.016） Scallop N.D. N.D. N.D. Sr, Cs and Pt: 48 (Mizuhopecten October 7, 2013 January 23, 2014 (Detection limit: (Detection limit: 0.016 0.038 N.D. (Detection limit: 0.0011 (Note 3) - Whole except shell yessoensis) 0.053） 0.0089） 0.00053） Alaska pollock N.D. N.D. N.D. N.D. Sr, Cs and Pt: 49 (Theragra September 19, 2013 January 23, 2014 (Detection limit: (Detection limit: 0.058 0.19 N.D. (Detection limit: (Detection limit: - Whole body chalcogramma) 0.092) 0.015） 0.00092） 0.00092） Alaska pollock N.D. N.D. N.D. N.D. Sr, Cs and Pt: 50 (Theragra September 19, 2013 January 23, 2014 (Detection limit: (Detection limit: 0.032 0.16 N.D. (Detection limit: (Detection limit: - Whole body chalcogramma) 0.093） 0.016） 0.00093） 0.00093） Alaska pollock N.D. N.D. N.D. N.D. Sr, Cs and Pt: 51 (Theragra October 2, 2013 January 23, 2014 (Detection limit: (Detection limit: 0.036 0.16 N.D. (Detection limit: (Detection limit: - Whole body chalcogramma) 0.085） 0.014） 0.00085） 0.00085） Alaska pollock N.D. N.D. N.D. N.D. Sr, Cs and Pt: 52 (Theragra October 2, 2013 January 23, 2014 (Detection limit: (Detection limit: 0.031 0.094 N.D. (Detection limit: (Detection limit: - Whole body chalcogramma) 0.087） 0.015） 0.00087） 0.00087） N.D. N.D. 53 Laver December 19, 2013 February 5, 2014 (Detection limit: 0.069 (Detection limit: 0.084 N.D. - - - Whole body 0.52） 0.060） N.D. Wakame seaweed 54 December 19, 2013 February 5, 2014 (Detection limit: 0.055 0.040 0.082 N.D. - - - Whole body (Undaria pinnatifida) 0.40） Scallop N.D. N.D. N.D. Sr, Cs and Pt: 55 (Mizuhopecten October 7, 2013 March 13, 2014 (Detection limit: (Detection limit: (Detection limit: 0.038 N.D. - - - Whole except shell yessoensis) 0.098） 0.012） 0.017） N.D. Olive flounder Sr & Cs: 56 September 30, 2013 March 13, 2014 (Detection limit: 0.026 1.94 6.07 N.D. - - - (Paralichthys olivaceus) Whole body 0.34） N.D. N.D. Redwing searobin Sr & Cs: 57 September 30, 2013 March 13, 2014 (Detection limit: (Detection limit: 1.50 3.20 N.D. - - - (Lepidotrigla microptera) Whole body 0.45） 0.015） N.D. N.D. Stone flounder Sr & Cs: 58 November 24, 2013 March 13, 2014 (Detection limit: (Detection limit: 1.94 4.85 N.D. - - - (Kareius bicoloratus) Whole body 0.29） 0.015） N.D. N.D. Crimson sea bream Sr & Cs: 59 November 24, 2013 March 13, 2014 (Detection limit: (Detection limit: 1.22 2.96 N.D. - - - (Evynnis japonica) Whole body 0.43） 0.024） Rockfish N.D. Sr & Cs: 60 September 11, 2013 May 23, 2014 0.21 23.4 51.4 N.D. - - - (Sebastes cheni) (Detection limit: 1.1） Whole except viscera N.D. Olive flounder Sr & Cs: 61 July 29, 2013 May 23, 2014 (Detection limit: 0.018 2.15 5.01 N.D. - - - (Paralichthys olivaceus) Whole body 0.09） N.D. Olive flounder Sr & Cs: 62 July 29, 2013 May 23, 2014 (Detection limit: 0.016 0.97 2.64 N.D. - - - (Paralichthys olivaceus) Whole body 0.08） N.D. N.D. North Pacific krill Sr & Cs: 63 June 30, 2012 May 23, 2014 (Detection limit: (Detection limit: 0.17 0.24 N.D. - - - (Euphausia pacifica) Whole body 0.023） 0.0077） N.D. N.D. Pacific saury Sr & Cs: 64 June 26, 2014 November 27, 2014 (Detection limit: (Detection limit: 0.15 0.49 N.D. - - - (Cololabis saira) Whole except viscera 0.029） 0.0077） N.D. N.D. Spiny dogfish Sr & Cs: 65 July 8, 2014 November 27, 2014 (Detection limit: (Detection limit: 0.97 2.98 N.D. - - - (Squalus acanthias) Whole except viscera 0.043） 0.0087） N.D. N.D. Pacific cod Sr & Cs: 66 July 9, 2014 November 27, 2014 (Detection limit: (Detection limit: 0.95 2.91 N.D. - - - (Gadus macrocephalus) Whole except viscera 0.058） 0.011） N.D. N.D. Beach conger Sr & Cs: 67 July 9, 2014 November 27, 2014 (Detection limit: (Detection limit: 0.91 2.66 N.D. - - - (Conger japonicus) Whole except viscera 0.048） 0.011） N.D. N.D. N.D. N.D. N.D. N.D. Red seabream 68 September 1, 2014 March 30, 2015 (Detection limit: (Detection limit: (Detection limit: 0.11 N.D. (Detection limit: (Detection limit: (Detection limit: Whole except viscera (Pagrus major) 0.23） 0.033） 0.036） 0.0023） 0.0024） 0.0018） N.D. N.D. N.D. N.D. N.D. Common sea squirt Whole body 69 September 9, 2014 March 30, 2015 (Detection limit: (Detection limit: 0.042 0.12 N.D. (Detection limit: (Detection limit: (Detection limit: (Halocynthia roretzi) (edible part) 0.055） 0.0095） 0.00041） 0.00041） 0.00042） N.D. N.D. N.D. N.D. N.D. Pacific saury 70 September 4, 2014 March 30, 2015 (Detection limit: (Detection limit: 0.029 0.13 N.D. (Detection limit: (Detection limit: (Detection limit: Whole body (Cololabis saira) 0.074） 0.010） 0.0011） 0.0011） 0.00079）

Table 1-4 Inspection Results for Radioactive Strontium in Fishery Products (cont.)

Test Result (Unit: Bq/kg）

NO Species Sampling date Publication date Sr-89 Sr-90 Cs-134 Cs-137 I-131 Pt-238 Pt-239+240 Am-241 Ref. (analyzed part)

N.D. N.D. N.D. N.D. N.D. N.D. Red seabream 71 September 16, 2014 March 30, 2015 (Detection limit: (Detection limit: (Detection limit: 0.12 N.D. (Detection limit: (Detection limit: (Detection limit: Whole except viscera (Pagrus major) 0.21） 0.033） 0.034） 0.0027） 0.0023） 0.0013） Alaska pollock N.D. N.D. N.D. N.D. N.D. 72 (Theragra September 16, 2014 March 30, 2015 (Detection limit: (Detection limit: 0.057 0.27 N.D. (Detection limit: (Detection limit: (Detection limit: Whole except viscera chalcogramma) 0.11） 0.017） 0.00086） 0.00081） 0.00070） Scallop N.D. N.D. N.D. N.D. N.D. Whole body 73 (Mizuhopecten September 18, 2014 March 30, 2015 (Detection limit: (Detection limit: 0.030 0.064 N.D. (Detection limit: (Detection limit: (Detection limit: (edible part) yessoensis) 0.074） 0.012） 0.00063） 0.00063） 0.00041） N.D. N.D. N.D. N.D. N.D. Common sea squirt Whole body 74 September 9, 2014 March 30, 2015 (Detection limit: (Detection limit: 0.017 0.070 N.D. (Detection limit: (Detection limit: (Detection limit: (Halocynthia roretzi) (edible part) 0.084） 0.013） 0.0010） 0.0010） 0.0011） N.D. N.D. N.D. N.D. N.D. Southern mackerel 75 September 28, 2014 March 30, 2015 (Detection limit: (Detection limit: 0.024 0.13 N.D. (Detection limit: (Detection limit: (Detection limit: Whole except viscera (Scomber australasicus) 0.084） 0.016） 0.0013） 0.0013） 0.00067） N.D. N.D. N.D. N.D. N.D. Southern mackerel 76 September 28, 2014 March 30, 2015 (Detection limit: (Detection limit: 0.031 0.16 N.D. (Detection limit: (Detection limit: (Detection limit: Whole except viscera (Scomber australasicus) 0.084） 0.015） 0.0012） 0.0013） 0.00063） N.D. N.D. N.D. N.D. N.D. Common sea squirt Whole body 77 September 29, 2014 March 30, 2015 (Detection limit: (Detection limit: 0.029 0.10 N.D. (Detection limit: (Detection limit: (Detection limit: (Halocynthia roretzi) (edible part) 0.059） 0.011） 0.0015） 0.0013） 0.0012） Scallop N.D. N.D. N.D. N.D. N.D. Whole body 78 (Mizuhopecten October 15, 2014 March 30, 2015 (Detection limit: (Detection limit: (Detection limit: (Detection limit: N.D. (Detection limit: 0.0022 0.0015 (edible part) yessoensis) 0.048） 0.011） 0.022） 0.029） 0.00095） N.D. N.D. N.D. N.D. N.D. Shortfin mako shark Whole except viscera 79 September 30, 2014 March 30, 2015 (Detection limit: (Detection limit: 0.19 0.90 N.D. (Detection limit: (Detection limit: (Detection limit: (Isurus oxyrinchus) and head 0.067） 0.013） 0.0011） 0.0011） 0.00042） N.D. N.D. N.D. N.D. N.D. Shortfin mako shark Whole except viscera 80 September 30, 2014 March 30, 2015 (Detection limit: (Detection limit: 0.23 1.0 N.D. (Detection limit: (Detection limit: (Detection limit: (Isurus oxyrinchus) and head 0.057） 0.010） 0.00094） 0.00094） 0.00043） N.D. N.D. Japanese sandlance 81 April 7, 2015 June 30, 2015 (Detection limit: (Detection limit: 0.17 0.59 - - - - Whole body (Ammodytes personatus) 0.014） 0.0056） N.D. N.D. Japanese sandlance 82 April 7, 2015 June 30, 2015 (Detection limit: (Detection limit: 0.24 0.97 - - - - Whole body (Ammodytes personatus) 0.018） 0.0040） N.D. N.D. Japanese sandlance 83 April 20, 2015 June 30, 2015 (Detection limit: (Detection limit: 0.18 0.68 - - - - Whole body (Ammodytes personatus) 0.012） 0.0045） N.D. N.D. Japanese sandlance 84 April 20, 2015 June 30, 2015 (Detection limit: (Detection limit: 0.20 0.73 - - - - Whole body (Ammodytes personatus) 0.015） 0.0042） N.D. Rockfish 85 March 15, 2015 July 31, 2015 (Detection limit: 0.043 1.7 6.8 - - - - Whole except viscera (Sebastes cheni) 0.32） N.D. Rockfish 86 March 15, 2015 August 1, 2015 (Detection limit: 0.049 2.4 9.1 - - - - Whole except viscera (Sebastes cheni) 0.36） Alaska pollock N.D. N.D. 87 (Theragra April 17, 2015 October 8, 2015 (Detection limit: (Detection limit: 0.062 0.29 - - - - Whole except viscera chalcogramma) 0.060） 0.0064） Alaska pollock N.D. N.D. 88 (Theragra April 14, 2015 October 8, 2015 (Detection limit: (Detection limit: 0.024 0.12 - - - - Whole except viscera chalcogramma) 0.13） 0.0078） N.D. N.D. Pacific cod 89 April 17, 2015 October 8, 2015 (Detection limit: (Detection limit: 0.066 0.28 - - - - Whole except viscera (Gadus macrocephalus) 0.073） 0.0061） N.D. N.D. Pacific cod 90 April 14, 2015 October 8, 2015 (Detection limit: (Detection limit: 0.70 2.6 - - - - Whole except viscera (Gadus macrocephalus) 0.065） 0.0038） N.D. N.D. 91 Whitebait July 14, 2015 October 8, 2015 (Detection limit: (Detection limit: 0.042 0.21 - - - - Whole body 0.062） 0.0027） N.D. N.D. 92 Whitebait July 14, 2015 October 8, 2015 (Detection limit: (Detection limit: 0.044 0.27 - - - - Whole body 0.012） 0.0035） N.D. N.D. N.D. Pacific saury 93 July 11, 2015 January 25, 2016 (Detection limit: (Detection limit: (Detection limit: 0.15 - - - - Whole except viscera (Cololabis saira) 0.10） 0.0052） 0.029） N.D. N.D. N.D. Pacific saury 94 July 11, 2015 January 25, 2016 (Detection limit: (Detection limit: (Detection limit: 0.14 - - - - Whole except viscera (Cololabis saira) 0.046） 0.0037） 0.027） Gurnard N.D. Sr & Cs 95 (Chelidonichthys October 4, 2015 March 24, 2016 (Detection limit: 0.067 0.26 1.3 - - - - Whole except edible part Muscle and viscera spinosus) 0.60） N.D. Ocellate spot skate Sr & Cs 96 October 4, 2015 March 24, 2016 (Detection limit: 0.19 1.8 8.1 - - - - Whole except edible part (Okamejei kenojei) 0.52） Muscle and viscera Drum N.D. Sr & Cs 97 (Argyrosomus October 4, 2015 March 24, 2016 (Detection limit: 0.084 0.33 1.7 - - - - Whole except edible part argentatus) 0.56） Muscle and viscera Marbled flounder N.D. Sr & Cs 98 (Pleuronectes October 4, 2015 March 24, 2016 (Detection limit: 0.41 0.71 3.3 - - - - Whole except edible part Muscle and viscera yokohamae) 0.89） Littlemouth flounder N.D. Sr & Cs 99 (Pleuronectes October 5, 2015 March 24, 2016 (Detection limit: 0.084 0.41 1.8 - - - - Whole except edible part Muscle and viscera herzensteini) 0.47） N.D. Conger eel Sr & Cs 100 October 5, 2015 March 24, 2016 (Detection limit: 0.020 0.23 1.3 - - - - Whole except edible part (Conger myriaster) Muscle and viscera 0.26） N.D. Stone flounder Sr & Cs 101 October 20, 2015 March 24, 2016 (Detection limit: 0.039 0.43 1.9 - - - - Whole except edible part (Kareius bicoloratus) Muscle and viscera 0.30） N.D. Ocellate spot skate Sr & Cs 102 October 20, 2015 March 24, 2016 (Detection limit: 0.050 1.9 8.3 - - - - Whole except edible part (Okamejei kenojei) Muscle and viscera 0.24） Marbled flounder N.D. Sr & Cs 103 (Pleuronectes October 20, 2015 March 24, 2016 (Detection limit: 0.067 0.66 3.0 - - - - Whole except edible part Muscle and viscera yokohamae) 0.37） N.D. Seabass Sr & Cs 104 October 16, 2015 March 24, 2016 (Detection limit: 0.10 0.89 3.9 - - - - Whole except edible part (Lateolabrax japonicus) Muscle and viscera 0.53）

Note 1: Sample nos. 5 & 10-14 were harvested by the Japan Fisheries Research and Education Agency in the waters off of Fukushima, an area in which fishing operations are under suspensions, and hence samples like these will not reach the market. Note 2: According to the Nuclear Regulation Authority’s Environment Radiation Database, up through the period of 2000-2010 prior to the Fukushima Daiichi NPS accident, the fish, shellfish and algae in the sea zones around Japan contained strontium-90 in concentrations between 0.26 Bq/kg and below the minimum detectable level. Note 3: According to the Nuclear Regulation Authority’s Environment Radiation Database, up through the period of 2000-2010 prior to the Fukushima Daiichi NPS accident, the fish and shellfish in the sea zones around Japan contained plutonium-238 in

concentrations between 0.0016 Bq/kg and below the minimum detectable level. Concentrations of plutonium-239+240 were between 0.073 Bq/kg and below the minimum detectable level. Note 4: The levels of Americium 241 observed in past study (Hashimoto et al., 2002 [30]) are: 0.0022 Bq/kg-wet (n=12, 0.0013 - 0.0043 Bq/kg-wet) for Clam (Meretrix lamarckii) (molluscous part), 0.0017 Bq/kg-wet (n=7, 0.0012 - 0.0029 Bq/kg-wet) for

Clam (Gomphina melanegis) (molluscous part)、0.00094 Bq/kg-wet (n=16, 0.00048 - 0.0016 Bq/kg-wet) for Ezo abalone (muscle part), 0.0021 Bq/kg-wet (n=16, 0.00099 - 0.0046 Bq/kg-wet) for Ezo abalone (visceral part) . Note 5: Nos. 19, 20, 33, 34, 40 have undetermined harvest locations and are therefore not shown in the map. Note 6: Nos. 18 – 40 were provided by the FY2012 Project on Clarifying the Impact of Nuclear Substances Note 7: Nos. 41 – 47, 53 – 59 were provided by the FY2013 Project on Clarifying the Impact of Nuclear Substances. Note 8: Nos. 48 – 52 was provided by a research project commissioned by the FY2013 Radioactivity Research Fund. Note 9: Nos. 60– 80 were provided by a research project commissioned by the FY2014 Radioactivity Research Fund. Note 10: Nos. 81-104 was conducted primarily through a project to survey radioactive substance behavior in marine ecosystems in FY2015.

Figure 1-39 Sampling Sites

Table 1-5 Examples for Calculating the Effective Dose of Strontium-90

Sample Concentration of Effective dose coefficient of Annual effective dose *2 Name of fish species no. *1 strontium-90Bq/kg strontium-90(adults) mSv / Bq mSv

10 Rockfish (Sebastes cheni) 1.2 2.8×10-5 0.026

13 Icefish 0.40 2.8×10-5 0.0086

98 Marbled sole 0.41 2.8×10-5 0.0086 *1 Corresponds to “No.” in Table 1-4. *2 2.1 kilograms of given fish species consumed daily in Table 1-4 (calculated based on the assumed average amount ingested by an adult male, exclusive of potable water, daily for a year).

1-3-2 Survey of Radionuclides Mentioned in the CODEX Guidelines The establishment of radioactive cesium limits in Japan based on consideration of the influence of other radionuclides was described in 1-1-1. Similarly, the Codex Alimentarius Commission also presents “guideline levels” for radioactive material in food in preparation for an emergency situation, such as a nuclear accident or intentional release [9]. Some countries and regions utilize these levels as limits for radioactive material or establish their own import food limits based upon them. Consequently, investigating radionuclide data that is provided in CODEX could be expected to strengthen international trust in the safety of Japanese food products and, as a result, lead to the relaxation or abolishment of import regulations. Given this, the Ministry of Agriculture, Forestry and Fisheries (MAFF) conducted a survey on these radionuclides in FY2014.

(1) Thinking Behind the Survey In FY2014, MAFF measured the concentrations of radionuclides noted in the CODEX guidelines (Table 1-6) in commonly exported fish species and main fish species inhabiting the Pacific Ocean off of eastern Japan. MAFF excluded from its scientific findings some radionuclides that are thought to be unnecessary for the purposes of the survey. MAFF measured a total of 44 samples of sardines, salmon, mackerel, saury, Alaska pollock, scallops, ascidians, and red seabream for nine radionuclides that can be measured with gamma ray spectrometry (americium-241 [Am-241], ruthenium-106 [Ru-106], iodine-131 [I-131], uranium-235 [U-235], cobalt-60 [Co-60], ruthenium-103 [Ru-103], cesium-134 [Cs-134], cesium-137 (Cs-137), and cerium-144 [Ce-144]). It also measured a total of eight samples of mackerel, saury, Alaska pollock, scallops, and red seabream for strontium-89 (Sr-89), strontium-90 (Sr-90), plutonium-238 (Pu-238), and plutonium-239+240 (Pu-239+240).

The following are the radionuclides that were not measured and the reasons why they were excluded from the survey. 1) Iodine-129 (I-129), carbon-14 (C-14), and technetium-99 (Tc-99) The half-lives of these radionuclides are long (roughly 15.7 million years for I129, 5,700 years for C-14, and 210,000 years for Tc-99). Thus, the per-hour doses of radiation emitted from them is low compared to radioactive cesium (2.1 years for Cs-134 and 30 years for Cs-137) and other radionuclides with short half-lives when the number of radionuclides is the same. Moreover, in the case of C-14, it is thought that the amount produced in a nuclear reactor is lower than that produced by the interaction of cosmic rays and nitrogen. Additionally, like tritium of 3) below, it is not thought to concentrate in the bodies of organisms. 2) Sulfur-35 (S-35) and iridium-192 (Ir-192) The half-lives of these radionuclides are short (87.51 days for S-35 and 73.831 days for Ir-192). Thus, given that four years have passed since the accident, it is thought that the number of radionuclides has decreased significantly since the accident and therefore no radioactive material originating from the accident can be ascertained. 3) Tritium (H-3) Because its effective dose coefficient per 1 Bq is small compared to radioactive cesium and other radionuclides and it is metabolized together with water and organic matter, it is quickly discharged from the body with almost no concentration remaining.

Table 1-6 CODEX’s Guideline Levels (Bq/kg) Foods other than infant Radionuclide Infant foods foods

238 239 240 241 Pu, Pu, Pu, Am 1 10

90 106 129 131 235 Sr, Ru, I, I, U 100 100

35 60 89 103 134 137 144 192 S, Co, Sr, Ru, Cs, Cs, Ce, Ir 1,000 1,000

3 14 99 H, C, Tc 1,000 10,000

(Values are totals of each radionuclide group.)

(2) Survey Results Table 1-7 shows the results of the measurements. Among the radionuclides measured for the survey, all were below the detection limit with the exception of one sample in which Pu-239+240 was detected at a level within the range detected for the same species in adjacent ocean areas prior to the accident (2001 to 2010, N.D. to 0.017 Bq/kg). The CODEX guidelines state that “the activity concentrations of each radionuclide within the same group should be added together”. Almost all of the radionuclide concentrations measured in the survey was below the detection limit. However, even when a concentration equaled the detection limit, it is thought that the concentration was not at a level that can influence concentration calculations when determining whether or not it exceeds the CODEX guideline level. Four years since the accident, the amount of radioactive material in fishery products has decreased significantly, and no radioactive cesium was detected in the MAFF survey. However, it is a fact that concerns have been expressed regarding radionuclides other than cesium, particularly in other countries. Although the survey involved a limited number of fish species and samples, it detected no values for CODEX-listed non-cesium nuclides in marine organisms that are commonly exported. It is thought the survey’s results will prove effective in demonstrating the safety of Japan’s fishery products in efforts to persuade other countries to lift their import restrictions.

< Inspection conditions, etc. >

(Period of sample collection) ・ December 20, 2014, to January 5, 2015

(Assessment bodies) ・ Measurement with gamma ray spectrometry, Sr-89, Sr-90: Isotope Research Institute ・ Pu-238, Pu-239+240: Kyushu Environmental Evaluation Association

(Tested body parts) Measurement with gamma ray spectrometry: muscle; measurement of Sr-89, Sr-90, Pu-238, and Pu-239+240: entire fish except intestines

(Detection limit in measurement with gamma ray spectrometry) Measurement was conducted so that the detection limit for Cs-134 and Cs-137 would be roughly 0.7 Bq/kg in each case (2,000 seconds to 4,000 seconds); given that the guideline level for infant foods of the group including Am-241 is 1 Bq/kg, measurement of some samples was conducted so that the detection limit for Am-241 would be roughly 1 Bq/kg (10,000-seconds to 40,000-second measurement).

Table 1-7 Radioactive Material Concentrations in Fishery Products for Radionuclides Noted in the CODEX Guidelines 1234 5 678

Foods Specimen検体 Sardines Alaska Pollock Scallops Ascidians Red seabream Maximum 乳児用Infant 乳児用食品イワシ類Salmon サケサバ類Mackerel Pacific サンマ saury スケトウダラホタテホヤマダイ検出値の detection 食品foods 以外の食品other than Aomori, Miyagi, Iwate, Aomori, Iwate, 最大値 infant Miyagi, Chiba 青森、岩手、宮城、福島、岩手、宮城、青森、岩手、宮Miyagi, Aomori, Iwate Aomori, Iwate Mie, Ehime value Radionuclide核種宮城,千葉 Iwate, Fukushima, Miyagi, 青森、岩手青森、岩手三重、愛媛 foods Mi宮城yagi 千葉千葉城、福島、千葉Fukushima, Chiba Chiba Chiba Group total (All “N.D.” グループの No. of samples for 89Sr,90Sr, 238,Pu, indicate 合計 'Sr-89, Sr-90, Pu- GL GL 239+240,Pu, 0022 2101（全てNDのmaximum 238, Pu-239+240, 241Am*の検体数場合は検 Am-241* detection 出限界値limits) 上記以外の核種No. of nuclide (Bq/kg) (Bq/kg) の最大値） samples検体数 other than 3581011223 those above Measured測定値 value Unmeasured未測定 Unmeasured 未測定 ND ND ND NDUnmeasured 未測定 ND 0.0015 0.00072 0.00049 0.00052 0.00082 0.0015 238Pu 検出限界値Detection limit ～～～～ 0.00115 0.00072 0.00057 0.00082 0.0015 Measured測定値 value Unmeasured未測定 Unmeasured 未測定 ND ND ND 0.0023Unmeasured 未測定 ND 0.0023 239Pu＋ 0.00061 0.00048 0.00051 0.0014 0.0012 240Pu Detection検出限界値 limit ～～～～ 0.00097 0.00061 0.00056 0.0014 0.0012 3 110 Measured測定値① value (1) Unmeasured未測定 Unmeasured 未測定 ND ND ND NDUnmeasured 未測定 ND 1.1 0.8 0.9 0.7 1.0 0.8 検出限界値(約 Detection limit ～～～～～ 1 (approx.1Bq/kg) 1 Bq/kg) 1.1 1.0 0.9 1.0 0.8 241Am Measured測定値② value (2) ND ND ND ND ND ND ND ND 2.8 2.0 2.4 1.2 1.7 1.8 2.5 2.6 2.3 検出限界A lower 検出限界値Detection limit ～～～～～～2.4 2.6 2.5 2.4 2.6 2.8 2.6 2.6 値を下げたdetection 241Amlimit forの 90Sr Measured測定値 value ND ND ND ND ND ND ND ND 0.019 Am‐241 検出限界 0.018 0.018 0.019 0.018 0.018 was used. 値を使用 Detection検出限界値 limit ～～～～～ 0.019 0.019 0.019 0.018 0.018 106Ru Measured測定値 value ND ND ND ND ND ND ND ND 7.3 4.2 5.5 2.9 4.0 4.2 5.0 5.1 5.0 Detection検出限界値 limit ～～～～～～7.2 6.4 6.5 6.5 6.1 6.9 5.6 7.3 129I Unmeasured（未測定） 100 100 131I Measured測定値 value ND ND ND ND ND ND ND ND 0.66 9 0.45 0.58 0.27 0.39 0.45 0.51 0.52 0.53

Detection検出限界値 limit ～～～～～～0.65 0.59 0.58 0.62 0.59 0.61 0.66 0.66

235U Measured測定値 value ND ND ND ND ND ND ND ND 1.3 0.66 0.81 0.58 0.60 0.75 0.78 0.84 0.85 ～～～～～～Detection検出限界値 limit 1.0 1.0 0.9 1.0 0.9 1.3 0.9 1.1 0 0000 35S Unmeasured（未測定） 60Co Measured測定値 value ND ND ND ND ND ND ND ND 1.1 0.64 0.72 0.41 0.44 0.69 0.76 0.73 0.77 Detection検出限界値 limit ～～～～～～0.76 1.0 1.0 1.0 1.0 1.1 1.0 1.1 89Sr Measured測定値 value Unmeasured未測定 Unmeasured 未測定 ND ND ND NDUnmeasured 未測定 ND 0.17 0.07 0.08 0.10 0.10 0.067 Detection検出限界値 limit ～～～～ 0.07 0.11 0.17 0.10 0.067 103Ru Measured測定値 value ND ND ND ND ND ND ND ND 0.90 0.47 0.55 0.33 0.50 0.55 0.61 0.54 0.55 Detection検出限界値 limit ～～～～～～0.69 0.74 0.90 0.73 0.71 0.62 0.71 0.77 1,000 1,000 134Cs Measured測定値 value ND ND ND ND ND ND ND ND 0.69 8 0.46 0.56 0.33 0.31 0.54 0.69 0.52 0.55 Detection検出限界値 limit ～～～～～～0.46 0.56 0.33 0.31 0.54 0.69 0.52 0.55 137Cs Measured測定値 value ND ND ND ND ND ND ND ND 0.70 0.47 0.59 0.34 0.43 0.54 0.67 0.67 0.69 Detection検出限界値 limit ～～～～～～0.18 0.22 0.70 0.21 0.16 0.21 0.27 0.21 144Ce Measured測定値 value ND ND ND ND ND ND ND ND 4.7 2.9 3.6 2.0 2.8 3.4 3.8 4.0 4.0 Detection検出限界値 limit ～～～～～～4.3 4.4 4.7 4.4 4.2 4.6 4.3 4.4 192Ir Unmeasured（未測定）

3H,14C,99Tc 1000 10,000 Unmeasured（未測定） * 241Am検出限界を約1Bq/kgとして検査*The detection limit of Am-241 is inspected as approx. 1 Bq/kg.

(Box 5) Why weren’t Radioactive Strontium and Plutonium Targeted in the Survey?

As outlined in box 1, the maximum values set in April 2012 were set for radioactive cesium upon taking into account the impact of cesium-134, cesium-137, strontium-90, plutonium, and ruthenium-106, which among the nuclides believed to have been emitted as a result of the accident at the Fukushima Daiichi Nuclear Power Plant, have half-lives of no less than one year, in accordance with an evaluation conducted by the Nuclear and Industrial Safety Agency (Table 1-8). Monitoring has been conducted with radioactive cesium. One reason for this is that, compared to radioactive cesium, measurement of radioactive strontium and plutonium require a considerable amount of time, which effectively makes continuous monitoring of them difficult. Measuring these radionuclides requires completely reducing samples to ash (which requires at least 74 hours). Even if measurements are to be subsequently taken, it takes time for strontium (which requires 2 weeks), in particular, to produce its daughter nuclide, strontium-90. This makes utilizing it in routine food monitoring tests, where speed is of the essence, problematic. Consequently, monitoring is conducted by using radioactive cesium, which is comparatively easy to measure, as the indicator after including non-radioactive cesium effects so that the total of the above-mentioned radionuclides does not exceed 1 mSv/year. As for measurement of radioactive material in fishery products, radioactive cesium is measured based on a notification issued by the Ministry of Health, Labour and Welfare and analysis series of the Ministry of Education, Culture, Sports, Science and Technology as described in 1-1-2. For radioactive strontium and plutonium, measurement is conducted based on analysis series of the Ministry of Education, Culture, Sports, Science and Technology [11; 37; 38; 39; 40]. The Fisheries Agency and Japan Fisheries Research and Education Agency announce data on radioactive cesium, radioactive strontium, and plutonium in fishery products. A summary of how these data are measured is provided below. In addition, a flowchart showing the actual method for measuring radioactive strontium and plutonium is attached at the end of this report.

1. Radioactive cesium Because two-liter Marinelli beakers are commonly used, the method using them will be described here. It should be noted that small 100-ml beakers (U-8) are used when the amount of sample available is insufficient.

(Preprocessing of the sample (Figure 1-40))  When a two-liter Marinelli beaker is used, an amount of fish, etc., that provides a sample of at least two kg (edible parts) is made available (five to seven kg of unprocessed fish).  The sample is prepared as described below. To avoid contamination from mud and mud contained in the stomach, the sample must be carefully washed and its intestines must be carefully removed. ・ For small fish (when the entire fish is eaten whole), the entire fish (including the intestines) ・ For medium-size and large fish, only the muscular sections (excluding the skin, bones, head, and intestines) ・ For invertebrates (squid, octopus, etc.), the muscular sections (mantle) (excluding the intestines; the skin is used depending on the intended purpose) ・ The sample is cut with a knife or other utensil into thin pieces of around 1 cm (to take place as necessary in the case of small fish). The pieces are packed into an internal bag, making sure that no spaces form, and then the sample is weighed.

(Measurement (Figure 1-41))  The sample is measured with a germanium semiconductor detector. When the sample is measured in a two-liter Marinelli beaker (roughly two-kg sample) for 60 minutes, the target detection limit is 0.4 Bq/kg for cesium-134 and 0.5 Bq/kg for cesium-137.

Figure 1-40 Preparation of the sample Figure 1-41 Germanium semiconductor detector (Photos courtesy of the Marine Ecology Research Institute)

2. Radioactive strontium and plutonium (Preparing the sample) 1) Carbonization and ashing (Figure 1-42) All parts except the intestines are measured. Those parts are reduced to ash to create the measurement sample. When using the sample that was used to measure radioactive cesium (described in 1 above), all of the parts except the intestines are returned and then entirely reduced to ash. The process of reducing the sample to ash involves a “drying process” using a hot-air drying machine and then a “carbonization process” with an electric furnace. The entire process takes at least 74 hours.

2) Strontium-90 The post-ashing sample is dissolved and the strontium is separated out using a Na-type strong acid anion exchange resin column. The sediments containing strontium that are obtained from this process are left to sit for at least two weeks (the amount of time needed for radiation equilibrium) to allow the production of radioisotopes of yttrium, which is the daughter nuclide of strontium. Then yttrium-90 is separated out using coprecipitation with iron (III) hydroxide. The beta rays of the yttrium-90 are measured with a gas-flow GM counter (Figure 1-43) (when count efficiency is 27 % and measurement takes place for 60 minutes, the detection limit should be around 0.02 Bq/kg [raw]).

3) Plutonium-238, 239+240 After the post-ashing sample is dissolved in nitric acid, the plutonium is separated out and purified using an anion exchange resin column. The plutonium is electrodeposited onto a stainless steel plate, where it becomes a sample for measuring alpha rays. The process from separation of the sample to completion of electrodeposition takes about 30 hours. Then the measurement sample is quantitated with alpha-ray spectrometry using a silicon semiconductor detector (when count efficiency is 20 % and measurement takes place for 24 hours, the detection limit should be between 0.002 Bq/kg and 0.004 Bq/kg [raw]).

Table 1-8 Half-Lives of Radionuclides that were Considered when Setting Limits

Nuclide subject to controls (Physical) half-life Cesium-134 2.1 years Cesium-137 30 years Strontium-90 29 years Plutonium-238 87.7 years Plutonium-239 24110 years Plutonium-240 6564 years Plutonium-241 14.4 years Ruthenium-106 374 days

Figure 1-42 Ash Sample for Measurement Figure 1-43 Gas-Flow GM Counter

of Radioactive Sr and Pu (Beta-ray Counter)

(Photos courtesy of the Japan Fisheries Research and Education

Part Two. The State of Radionuclides Released into the Environment Chapter 1. Movement of Radioactive Cesium Released into the Environment

Radioactive cesium radionuclides released into the environment by the Fukushima Daiichi NPS accident are thought to have two paths of intake by fishery species. One path is through water in the environment, and another is through the intake of prey organism. The chemical properties of cesium are similar to those of potassium, and the two behave in the same way when entering the body of fish. Further, cesium is also (like potassium) excreted from the body through urination and similar processes, and hence a reduction in the concentration of radioactive cesium in the environment brings a reduction in the concentration of radioactive cesium in fishery products. This chapter will discuss the mechanism by which radioactive cesium enters the body of fish, as well as the movement and changes of radioactive materials emitted into the land, ocean, and environment.

2-1-1 Intake and Excretion by Fish [41] As with potassium and other minerals, radioactive cesium in environmental waters (ocean or freshwater) is, after being taken into the bodies of fish, gradually excreted from them (Figure 2-1). According to previous research, the concentration of radioactive cesium in marine fish is (including food-chain effects) 5 to 100 times higher than the concentration in the surrounding seawater, although there are differences among fish species. Depending on the concentration of radioactive cesium in the surrounding seawater and the intake/excretion capabilities of the fish, the concentration of radioactive cesium in fish can be temporarily high. When marine fish take in radioactive cesium or other minerals, their bodies work to quickly excrete the substance because osmotic pressure within their body is lower than that of sea water. In an environment with no radioactive cesium, half of the amount taken in is excreted from the body in approximately 50 days. For this reason, a reduction in the concentration of radioactive cesium in the surrounding seawater will result in a gradual reduction in radioactive cesium concentrations within the bodies of marine fish. In invertebrates, the majority of salts flow freely between the seawater and the inside of the invertebrates’ bodies because osmotic pressure within their body is equivalent to that of sea water. For this reason, radioactive cesium concentrations will drop off more quickly in invertebrates than in marine fish if there is a reduction in radioactive cesium concentrations in the surrounding seawater. In this way, radioactive cesium within marine products do not behave like mercury or organochlorine compounds in that they do not accumulate within fishes’ bodies through the food chain. Moreover, current concentrations of radioactive cesium in ocean waters are, as discussed in detail in 2-2-2, quite low outside of port. Therefore, it is thought that concentrations of radioactive cesium in marine products will drop with the passage of time. Meanwhile, the bodies of freshwater fish naturally attempt to retain radioactive cesium and other minerals because osmotic pressure within their body is higher than that of environmental water, and freshwater fish require more time to excrete radioactive cesium than do marine fish.

Figure 2-1 Intake of Radioactive Materials by Fish

2-1-2 Movement within the Environment Radioactive cesium in the ocean is diluted and dispersed with large amounts of water as it is transported by ocean currents. It also may be carried onto the ocean floor sticking to suspended particles or coagulation sedimentation. Radioactive cesium present in marine soil is thought to move with the soil as it is gradually scattered around. For inland waters, radioactive cesium that falls on mountains or plains is transported via rain or melting snow into rivers, lakes, and marshes, eventually pouring into the ocean or falling to the bottom of a lake or marsh (Figure 2-2). After the Fukushima Daiichi NPS accident, Fukushima Prefecture; the Ministry of Education, Culture, Sports, Science and Technology (now the Nuclear Regulation Authority and the Ministry of the Environment); and TEPCO conducted a study on the movement and changes of radioactive cesium in the environment. This study revealed that concentrations of radioactive cesium in seawater and marine soil along the coast of Fukushima Prefecture and adjacent prefectures were high around the nuclear power plant immediately after the accident but thereafter declined (Figure 2-3).

Figure 2-2 Progression of Contamination due to the Nuclear Accident

Seawater (Bq/L) Sea‐bottom soil (Bq/kg‐dry)

Fukushima Daiichi Nuclear Power Plant

(Compiled by the Fisheries Agency based on materials provided by the Nuclear Regulation Authority and Ministry of Education, Culture, Sports, Science and Technology) Figure 2-3 Results of the Monitoring of Radioactive Cesium in Seawater and Marine Soil off the Coast of Fukushima

Chapter 2. The Leakage of Contaminated Water into the Fukushima Daiichi NPS Port

2-2-1 Impact of Contaminated Water Leakage and Countermeasures In May 2013, a high concentration of tritium was detected in groundwater at the seawall area between intakes of unit 1 and unit 2. TEPCO conducted a survey of the groundwater in the area, and announced at the

62 end of July 2013 that contaminated groundwater from the seawall was leaking into the port. According to the TEPCO study, the quantity of cesium radionuclides that has leaked into the ocean since May 2011 is estimated to be far less than the quantity released in April 2011 (see Box 6). Moreover, although some amount of radioactive materials were detected in water in the port, concentrations at the port entrance were low and the impact outside the port is expected to be limited (Figure 2-4). Concentrations of radioactive cesium and strontium-90 in the marine area around the Fukushima Daiichi are in a decreasing trend. As for plutonium, no significant increase compared to before the accident has been observed. Three basic principles guide efforts to stop the leakage of contaminated water: “remove” the source of contamination; “isolate” water from the source contamination; and “prevent leakage” of contaminated water [42]. As measures to isolate water from sources of contamination, groundwater is pumped out or cleaned and then discharged before it has a chance to be contaminated. In addition, the construction of a frozen ground wall will inhibit the inflow of groundwater into buildings and reduce the incidences of water contamination. As measures for preventing sources of contamination from leaking, contaminated seawall foundations have been shored up and seaward-facing impermeable walls have been installed to significantly reduce the amount of radioactive substances that flow out into the ocean, producing demonstrable improvements in the quality of water in the bay. Water is also isolated from sources of contamination. Further, to prevent the spread of contaminated marine organism out of the port, TEPCO has installed nets at the port entrance and carries out exterminations inside the port [43].

Entrance of the Unit port

Unit tritium total β-ray tritium cesium (134+137) total β-ray cesium (134+137)

The value of detection limit were plotted in the cases when the detected radioactivity Point near the south concentration was lower than the limit discharge channel

Point north side of Unit 1-4 water intake channel (north side of East Seawall Break)

Unit

tritium total β-ray

cesium (134+137)

(Compiled by the Fisheries Agency based on materials produced by TEPCO)

Figure 2-4 Impact of Contaminated Water Leakage into the Fukushima Daiichi NPS Port (Source: Produced by the Fisheries Agency based on materials supplied by TEPCO [44])

(Box 6) Quantity of Radioactive Material Leaked into the Ocean (Est.)

According to estimation by TEPCO, the amount of cesium-137 leaked into the ocean over the 850 days since May 2011 is approximately 1 to 20 TBq [45]. This quantity is 1/47 to 1/940 the amount of cesium-137 leaked from the Fukushima Daiichi NPS Reactor Unit 2 from April 1 to April 6, 2011 (940 TBq [46]) in highly contaminated water. The main source of the contamination of fishery products today is thought to be the large leakage that took place from April 1 to April 6. Later leakages are considered to have contributed little to this contamination. Further, inspection results on radioactive strontium in fishery products are described in Chapter 3 of Part One. Additionally, tritium has an effective dose coefficient (the coefficient that expresses the relationship between the amount of radioactive substance taken in and exposure dosage) that is 1/700 of that of cesium-137 (ICRP Publication 72, Biological Half-life [47]). When found in the natural world, tritium is primarily found as water, and hence even if it is taken in by living creatures such as humans or fish, it is not concentrated and is quickly excreted. It is inconceivable that that tritium will be found within food in considerable doses, and hence it is not considered relevant to the limits for food items [10].

Comparison2011年4月の汚染水漏 of the amount洩と、東京電力が試算した2011年5月以降の汚染水漏洩における、放射性物質 of radionuclides in the contaminated water leaked in Apr.2011 with that in the漏洩量の比較 contaminated water leaked from May.2011 to Aug.2013, which was estimated by TEPCO

The amount of radionuclides in the The amount of radionuclides東京電力の試算による in the contaminated water leaked since may.2011, 2011年4月の漏洩量① 1) contaminated water leaked in Apr.2011 2011年5月以降の漏洩量②which was estimated by TEPCO 2) Radionuclides放射性核種漏洩量漏洩量 Leak漏洩期間 periods Leak amount (Bq) Leak漏洩期間 periods Leak amount (Bq) （単位：ベクレル）（単位：ベクレル）セシウム134+137Cesium-134+137※1 66日間 days ca. 1,800兆 18 * 1014 -

セシウム137Cesium-137※2 66日間 days ca. 940兆9.4 * 1014 850日間850 days ca.約1兆～約20兆 1 * 1012 - ca. 2 * 1013 ストロンチウム90Strontium -90 - 850日間850 days 約7,000億～約10兆ca. 7 * 1011 - ca. 1 * 1013 トリチウムTritium - 800日間800 days ca. 約20兆～約40兆 2 * 1013 - ca. 4 * 1013

Note:（注）ストロンチウム 220 Bq/L (Aug.19, 902013),については、 49 Bq/L (Aug.19,1～4 号機取水口内北側（東波除堤北側）で2013) and 0.29 Bq/L (Jun.26, 2013) for strontium-90220 Bq/L were（2013/8/19 detected at the採取）、港湾 North side of 口で（採取）、南放水口付近で（採取）検出。 Unit1-449 water Bq/L intake2013/8/19 channel (north side of East Seawall Break),0.29 Bq/L at the2013/6/26 port entrance and at the point near the south discharge channel, ※２は※１の内数 respectively

Sources: Created based on information from: 1) Material publicized by the government [46] 2) Cesium-137 and strontium-90: estimation by TEPCO [45], tritium: estimation by TEPCO [48] Concentration factor of fish species

Fish Mollusk Seaweeds Cesium 5 - 100 10 - 60 10 - 50 Strontium 1 - 3 1 - 10 10 Tritium 1 1 1 Sources: IAEA TRS 422 [49]; Yamagata, “Seibutsu noushuku” [50]

2-2-2 Concentrations of Radioactive Cesium in Fishery Products In July 2013, TEPCO reported that contaminated groundwater had leaked from a seawall into the plant port. According to the monitoring results, the influence to sea water has not been observed outside of the port. However, the controversy over this leakage of contaminated water reignited domestic and international fears over fishery products in the Fukushima area and, in September of the same year, the Republic of Korea announced that it would strengthen its regulations on fishery product imports from Japan. This section will explain the results of a statistical analysis to examine the significance of an effect by the July 2013 leakage on radioactive cesium concentrations in Fukushima area fishery products.

(1) Comparison of Cesium Concentrations in Fishery Products: Just after the accident and in FY2013 As stated in 2-2-1, calculations regarding the leakage of contaminated water, published by TEPCO in July 2013, show that the amount of cesium-137 estimated to have leaked into the ocean over the 850 days since May 2011 is approximately 1/47th to 1/940th the amount leaked from April 1 to April 6, 2011.For this reason, the contamination immediately following the accident is thought to remain the major source of fishery product contamination today, and as seen in Chapter 1, radioactive cesium concentrations in marine products have been on a declining trend ever since the accident. Furthermore, if we were to assume that there was an effect from contaminated water leakage occurring after May 2011, marine products in Fukushima Prefecture would be expected to experience the largest effect. Inspection results in Fukushima from two periods—the six months immediately following the accident (April to September 2011) and the six months in FY2013 (October 2013 to March 2014) — are compared in Table 2-1. As can be seen in the table, the median radioactive cesium concentration has declined in every fish species. The following statistical test was performed to determine whether this decline in median concentration is statistically significant.

1) Period of comparison April to September 2011, 6 months (accident aftermath); and October 2013 to March 2014, 6 months.

2) Fish species compared All Fukushima Prefecture marine species for which 20 or more results are available in the given period.

3) Method of statistical test As in Chapter 1, the distributions of radioactive cesium concentrations in fishery products are not bilaterally symmetrical from left to right, but rather most distributions have a high frequency of low-concentration samples and then trail off to the right. Therefore, for comparison of unpaired two groups, a non-parametric method, Mann–Whitney U test was used to test for the significance of a difference in medians between the two samples.

Null hypothesis H0: There is no difference, immediately post-accident versus FY2013, in radioactive cesium concentrations within the target fish species,

Alternative hypothesis H1: Radioactive cesium concentrations within target fish species in FY2013 are

lower than concentrations in immediately post-accident. With these as hypotheses, a one-sided test was performed with a significance level of 5 %. When both cesium-134 and 137 are below detection limit, the sum of their respective detection limits is used. Detection limits for 2011 are not available in the same for, and therefore the mean of 2012 detection limits, 16 Bq/kg, was used. In Table 2-1, even when actual readings were below the detection limit, the calculated value was used.

4) Results As shown in Table 2-2, for every fish species the null hypothesis was rejected at a 5 % significance level. It can be concluded that the decrease in median radioactive cesium concentration, from the post-accident period of April to September 2011 to the period of October 2013 to March 2014, is significant.

Table 2-1 Comparison of Radioactive Cesium in Fishery Products Between Two Periods 2011.4～2011.9 2013.10～2014.3 Species Number of Median Interquartile range Number of Median Interquartile inspections (Bq/kg) (Bq/kg) inspections (Bq/kg) range (Bq/kg)

fat greenling 48 170 (110～410) 156 16 (14～19)

brown hakeling 20 150 (110～490) 90 16 (15～17)

monkfish 20 53 (36～79) 59 16 (15～17)

ocellate spot skate 37 310 (150～600) 88 42 (20～80)

whitebait 40 53 (16～190) 61 16 (15～17)

slime flounder 41 62 (35～190) 156 16 (14～18)

olive flounder 73 130 (75～200) 209 16 (14～18) gurnard 21 120 (79～140) 61 15 (14～17) Japanese jack mackerel 25 28 (16～86) 67 16 (14～17)

conger eel 25 25 (16～53) 91 15 (14～17)

littlemouth flounder 35 73 (59～150) 184 15 (13～17)

marbled flounder 37 180 (71～250) 113 17 (14～21) John Dory 23 25 (18～54) 32 15 (14～16)

Table 2-2 Comparison of Radioactive Cesium in Fishery Products Between Two Periods (Results of statistical test) Test Species P-value statistic (U) fat greenling <0.001 7236.5

brown hakeling <0.001 1800

monkfish <0.001 1154

skate <0.001 3057.5

whitebait <0.001 2018.5

slime flounder <0.001 5331

olive flounder <0.001 14709.5 gurnard <0.001 1280 Japanese jack mackerel <0.001 1295.5 conger eel <0.001 1705.5 littlemouth flounder <0.001 6412

marbled flounder <0.001 4042 John Dory <0.001 613

(2) Comparison of Before and After the Leakage of Contaminated Water The July 2013 TEPCO report on the contaminated water leakage reignited domestic and international fears over fishery products in the Fukushima area, and in September of the same year, the Republic of Korea announced that it would strengthen its regulations on imports from Japan. According to the monitoring results, the influence to sea water has not been observed outside of the port. Hence it is thought that there was no increase in radioactive cesium concentrations among fishery products. Table 2-3 compares inspection results from two periods: latter period, a 6-month period from April to September 2013 in which TEPCO announced the leakage; and former period, the preceding 6-month period from October 2012 to March 2013. While the median radioactive cesium concentration for many of the fish species is either unchanged or drops from former period to latter period, some of the species display an increase in median. The following statistical test was performed to determine whether this increase in median in some species from one period to the next is statistically significant.

1) Period of comparison October 2012 to March 2013, 6 months (former period); and April to September 2013, 6 months (latter period)

2) Fish species compared All Fukushima Prefecture marine species for which 20 or more results are available in the given period and

67 which also displayed an increase in median radioactive cesium concentration from one period to the next (fox jacopever (Sebastes vulpes), Alaska pollock and seabass).

3) Method of statistical test As in 2-2-2 (1), a Mann–Whitney U test was used to test for the significance of a difference in medians between two periods. Readings below the detection limit were treated in the same manner as in 2-2-2 (1).

Null hypothesis H0: There is no difference between former and latter period radioactive in cesium concentrations in the target fish species.

Alternative hypothesis H1: There is an increase in radioactive cesium concentrations in the latter period relative to the former period. With these as hypotheses, a one-sided test was performed with a significance level of 5 %.

4) Results As Table 2-4 shows, in every fish species the null hypothesis was not rejected at a 5 % significance level. There was no significant increase in radioactive cesium concentrations from the former period of October 2012 to March 2013, to the latter period of April to September 2013.

Table 2-3 Comparison of Radioactive Cesium Concentrations Before and After the Contaminated Water Leakage Controversy 2012.10～2013.3 2013.3～2013.9 Interquartile Number of Median Number of Median Interquartile Species range inspections (Bq/kg) inspections (Bq/kg) range (Bq/kg) (Bq/kg) fat greenling 152 62 (25～140) 180 19 (15～57) flathead founder 75 16 (14～17) 69 15 (14～17) Ishikawa icefish 62 16 (14～17) 30 16 (15～17) stone flounder 91 36 (17～98) 70 17 (14～41) goldeye rockfish 27 130 (28～210) 30 24 (16～78) redwing searobin 64 15 (9.3～18) 64 14 (12～16) monkfish 41 16 (15～18) 59 16 (15～18) fox jacopever 28 18 (15～60) 33 40 (16～59) black rockfish 26 31 (15～130) 23 27 (16～51) hairy crab 23 16 (14～17) 57 16 (15～17) sea raven 42 24 (15～43) 80 16 (14～18) sand eel 28 16 (15～17) 38 15 (14～17) ocellate spot skate 95 100 (58～170) 96 55 (40～86) roughscale sole 33 16 (14～17) 94 15 (14～17) halfbeak 30 15 (14～16) 27 15 (14～16) whitebait 53 16 (15～17) 138 16 (15～17) rockfish 60 190 (91～310) 39 130 (78～240) dwarf squid 24 15 (15～16) 31 15 (15～16) Alaska pollock 44 15 (14～18) 41 16 (14～17) seabass 75 39 (18～73) 27 48 (19～145) slime flounder 135 17 (15～57) 190 16 (14～19) olive flounder 220 31 (16～61) 203 16 (14～30) gurnard Japanese 51 17 (12～19) 46 15 (12～17) jack mackerel 40 15 (13～17) 34 15 (14～17) conger eel 77 16 (13～18) 78 15 (12～17) littlemouth flounder 109 17 (13～30) 115 15 (13～17) marbled flounder 111 33 (18～53) 119 16 (14～27) Pacific cod 127 21 (14～44) 134 16 (14～29) John Dory 32 17 (14～20) 22 15 (12～16) Rikuzen flounder 65 16 (14～17) 124 16 (15～17) giant Pacific octopus 51 16 (14～17) 78 15 (14～17) shotted halibut 65 16 (14～20) 65 15 (13～17) chestnut octopus 57 16 (14～17) 126 16 (14～17) willowy flounder 66 15 (12～17) 103 15 (14～17) spear squid 52 16 (15～17) 37 15 (15～17) hildendorf saucord 55 15 (13～16) 84 15 (14～17)

Table 2-4 Comparison of Radioactive Cesium Concentrations Before and After the Controversy over the Leakage of Contaminated Water (Results of statistical test) Test Species P-value statistic (U) fox jacopever 0.22 408.5 Alaska pollock 0.64 943 Seabass 0.16 878.5

(3) Summary Based on the results of the test in 2-2-2 (1), we have confirmed a statistically significant decrease in radioactive cesium concentrations in Fukushima Prefecture marine product within every fish species tested since the immediate post-accident period. Second, the controversy over contaminated water leakage reignited domestic and international fears over fishery products in the Fukushima area, and in September 2013 the Republic of Korea announced that it would strengthen its regulations on imports from Japan. However, the results of the test in 2-2-2 (2) indicate that there was no statistically significant increase in radioactive cesium concentrations of Fukushima area marine products from the former period to the latter period.

Chapter 3. Monitoring of Radionuclides in the Ocean

Part One discussed the results of monitoring of radioactive cesium in fishery products. Monitoring of ocean waters and marine soil is not only conducted by TEPCO within the nuclear power station port; it is also periodically conducted in the vicinity of the nuclear plant, in the coasts of neighboring prefectures, off-shore area, and in the outer sea area (except marine soil) by TEPCO, the Nuclear Regulation Authority (NRA), the Ministry of the Environment, Fukushima Prefecture, and others. In the event of leakage from the Fukushima Daiichi NPS, TEPCO and relevant government agencies coordinate their efforts as necessary to provide the level of monitoring appropriate for the event. This data produced through this monitoring is published on the i websites of the relevant organization. This chapter will serve to summarize these monitoring results.

2-3-1 Results from Ocean Water Monitoring (Figure 2-5, Figure 2-6) The concentrations of radioactive materials in sea waters near the Fukushima Daiichi NPS showed a quite high value immediately after the accident in 2011, but the value has declined afterward. Regarding the impact of contaminated water to the sea, the IAEA stated that “although increased radionuclide concentrations have been monitored in the sea, these have occurred only in a small area within the port of the Fukushima Daiichi Nuclear Power Station.”, “The monitoring results that have been provided for the surrounding sea region and off shore areas indicated no rise in radionuclide concentrations and remain within the WHO guidelines for drinking water,” and “the IAEA considers the public is safe and sees no reason why this should not continue to be the case in the future” (December 20,2013)［51］. In addition to the above, the IAEA considers “marine environment to be stable” and has, based on the proficiency tests conducted in the marine monitoring project with the Government of Japan (where samples provided by the IAEA are analyzed by laboratories involved in testing and analytical results are submitted to the IAEA, then the IAEA confirms their performance in the analysis of radionuclides) and comparisons between Japanese laboratories and the IAEA in terms of the analysis of seawater samples (interlaboratory comparison whereby samples obtained jointly by the Japanese laboratories and the IAEA are analyzed by them respectively and the results thereof are then compared), concluded that “ both tests have shown a high level of accuracy of the data reported by Japanese laboratories” and that “This conclusion should increase confidence that the data regularly reported by NRA presents a reliable picture of the levels of radioactivity in the near-shore coastal waters east of Japan” [52, 53, 54].

i Nuclear Regulation Authority http://radioactivity.nsr.go.jp/ja/list/428/list-1.html

Legends

Figure 2-5 Sampling Points in the Vicinity of the Fukushima Daiichi NPS (Source: Excerpted from the Nuclear Regulation Authority website [55])

Sampling Point Point no. T-1 North side of 1F 5-6 water outlet

T-2-1 Coast Around 1F south water outlet

Around 2F north water outlet T-3

３km offshore of Ukedo River T-D1

３km offshore of 1F T-D5

Within 20 km radius ３km offshore of 2F T-D9

15km offshore of 1F T-5

Around 15km offshore of Odaka Area T-B1

Excerpt from Nuclear Regulation Agency website (based on reference documents made) [56]

Sampling Point: T-1 Surface ray Materials (Bq/L) (Bq/L) Materials Concentration of radioactive radioactive of Concentration

Date of Sampling

Sampling Point: T-2-1 (T-2 until Nov. 2012) Surface ray Materials (Bq/L) (Bq/L) Materials Concentration of radioactive radioactive of Concentration

Date of Sampling

Sampling Point: T-3 Surface ray Materials (Bq/L) (Bq/L) Materials Concentration of radioactive radioactive of Concentration

Date of Sampling

Sampling Point: T-5 Surface ray Materials (Bq/L) (Bq/L) Materials Concentration of radioactive radioactive of Concentration

Date of Sampling

Sampling Point: T-D1 Surface ray Materials (Bq/L) (Bq/L) Materials Concentration of radioactive radioactive of Concentration

Date of Sampling

Sampling Point: T-D5 Surface ray Materials (Bq/L) (Bq/L) Materials Concentration of radioactive radioactive of Concentration

Date of Sampling Sampling Point: T-D9 Surface ray Materials (Bq/L) (Bq/L) Materials Concentration of radioactive radioactive of Concentration

Date of Sampling

Sampling Point: T-B1 Surface ray Materials (Bq/L) (Bq/L) Materials Concentration of radioactive radioactive of Concentration

Date of Sampling

Figure 2-6 Changes in the Radioactive Material Concentrations in the Vicinity of the Fukushima Daiichi NPS and Coastal Ocean Waters (Source: Excerpted from the Nuclear Regulation Authority website [57])

2-3-2 Results from Marine Soil Monitoring (Figure 2-5, Figure 2-7) According to monitoring results since April 2012, radioactive cesium concentrations in marine soil within 20 km of the Fukushima Daiichi NPS vary depending on the measurement site but are in the range of 10 to several thousand Bq/kg as dry soil with no particular change observed over time. In this way, while radioactive cesium at a higher concentration than normal has accumulated in marine soil, this does not necessarily mean that radioactive cesium exceeding limits will be detected in fish and shellfish living in the given area of the sea. The reasons for this include the fact that the transfer coefficient from ocean water to marine soil is 2000 – 4000 (concentration in marine soil /concentration in ocean water), and hence the cesium in the ocean water sticks strongly to argilliferous soil on the ocean bottom; and also the fact that the transfer rate from marine soil to benthos is very small (0.04 – 0.17), meaning that it is difficult for cesium stuck to the clay to be adsorbed in the bodies of sea organisms. In addition, it is understood that, with the passage of time, it is taking on a form that cannot be utilized by living organisms. Meanwhile, cesium that is not stuck to argilliferous soil is relatively more easily taken in the bodies of sea organisms, and this cesium is considered to be one of the causes of contamination in fishery products [41]. The nuclear regulatory agency and the IAEA have, as well as the analysis of seawater samples outlined in 2-3-1, undertaken an ILC of analyses of marine soil samples from 2014 to 2015. The IAEA concluded that “IAEA-run comparison studies in 2014 and 2015, using seawater and sediment samples collected near Fukushima Daiichi NPS, also indicated that the participating Japanese laboratories’ results were reliable.”[87].

Sampling Point: T-1 Concentration of radioactive radioactive of Concentration soil) dry as (Bq/kg Materials

Sampling Point: T-2-1 (T-2 until Nov. 2012) Concentration of radioactive radioactive of Concentration soil) dry as (Bq/kg Materials

Sampling Point: T-3 Concentration of radioactive radioactive of Concentration soil) dry as (Bq/kg Materials

Sampling Point: T-5 Concentration of radioactive radioactive of Concentration soil) dry as (Bq/kg Materials

Sampling Point: T-D1 Concentration of radioactive radioactive of Concentration soil) dry as (Bq/kg Materials

Sampling Point: T-D5 Concentration of radioactive radioactive of Concentration soil) dry as (Bq/kg Materials

Sampling Point: T-D9 Concentration of radioactive radioactive of Concentration soil) dry as (Bq/kg Materials

Sampling Point: T-B1 Concentration of radioactive radioactive of Concentration soil) dry as (Bq/kg Materials

Figure 2-7 Radioactive Materials Concentrations in Marine Soil in the Vicinity of the Fukushima Daiichi NPS and Coastal Sea Area (Source: Excepted from the Nuclear Regulation Authority website [58])

Part Three. Research on the Mechanism by which Radionuclides are Transferred to Fishery Products Chapter 1. Relationship with Prey Organisms and Ecology of Fish Species

As seen in 2-3-1, ongoing monitoring of radioactive cesium in seawater off the coast of Fukushima Prefecture is being conducted and reveals that the concentration of radioactive cesium in seawater is returning to pre-accident levels at the Fukushima Daiichi NPS. At the same time, the concentration of radioactive cesium is declining at a slower pace in some species of demersal fish than in other species of fish, such that there is concern over the movement of radioactive materials through the medium of food. For this reason, it is important that we properly ascertain the dynamic state of radioactive cesium in the ecosystem and the processes by which radioactive cesium moves through the food chain. In this chapter, the results of research conducted by the Japan Fisheries and Education Agency jointly with Fukushima Prefecture and other institutions will be hereby explained [59].

3-1-1 Chronological Changes in the Concentration of Radioactive Cesium in Seawater in Sendai Bay and the Coastal Areas of Fukushima Prefecture From 2011 to 2015, the concentration of radioactive cesium in seawater in Sendai Bay and in the waters off the coasts of Chiba, Ibaraki, Fukushima, and Miyagi prefectures, and Onahama was measured. The concentration of radioactive cesium declined dramatically in 2011 and continued to decline on a year-on-year basis from 2012 onwards. According to a survey conducted in 2015, the concentration of cesium-137 was between 0.0012 and 0.033 Bq/L while the concentration of cesium-134 was between below minimum detection limits (approximately 0.0012 Bq/L) and 0.0075 Bq/L (Figure 3-1) [60, 61, 62].

3-1-2 Research on Radioactive Materials within Prey Organisms From 2011 to 2015, radioactive cesium concentrations were measured in zooplankton in Sendai Bay and waters off Fukushima. The concentration of radioactive cesium has been declining year on year, such that a survey conducted in 2015 indicated that the concentration of cesium-137 dropped from 0.14 to 0.39 Bq/kg and that the concentration of cesium-134 was below minimum detection limits (from 0.057 to 0.20 Bq/kg-wet) (Figure 3-2) [60, 63]. From May to October 2013, concentrations of radioactive cesium in samples of benthos collected within twenty kilometers of the Fukushima Daiichi Nuclear Power Station and the estuary of Abukuma River, which flows through the Fukushima and Miyagi Prefectures, were measured (Table 3-1, Table 3-2,Figure 3-3). These efforts revealed that the concentration of radioactive cesium in samples of benthos collected at each survey site was less than the concentration of radioactive cesium in the marine soil at each site where samples were collected (Table 3-2). With respect to benthos off the coast of Fukushima Prefecture, there were, even among polychaetes living in the marine soil, differences found in the concentration of radioactive cesium according to taxonomical group as a function of differences in feeding habits. Concentrations were found to be high in taxonomical groups of filter feeders or surface deposit feeders, such as Flabelligeridae and Terebellidae, and low in Glyceridae and other carnivorous groups (Table 3-2). The concentrations of radioactive cesium in benthos were typically measured for whole-body specimens, which contained the gut contents within their

78 digestive tract. Actually, internal gut contents were confirmed in the whole-body specimens of Flabelligeridae. Therefore, it is thought that difference in feeding habits among benthos influence on the measurement values.

off Joban_Sanriku coast

Sendai Bay Off Joban- Sanriku coast Oyashio_region Sendai bay

Onahama The concentration of Cs-137 in seawater off Joban-Sendai coast, Sendai bay and Oyashio-region has declined over time.

Cs-137 (Bq/L) (Bq/L) Cs-137

Days from 11 March 2011 Figure 3-1 Chronological Changes of the Concentration of Cesium-137 in Seawater off the Coast and Offshore Areas of Fukushima and Miyagi Prefectures

Off Joban - Sendai coast Sendai bay Oyashio- region The concentration of Cs-137 in

zooplanktons in waters off Joban-Sendai coast, Sendai Bay and Oyashio-region has declined

over time.

Cs-137 (Bq/kg-wet) (Bq/kg-wet) Cs-137

Days from 11 March 2011 Figure 3-2 Chronological Trend of Cs-137 Concentration within Zooplanktons

Table 3-1 Radioactive Cesium Concentration within Benthos Sampled at the Estuary of the Abukuma River - The concentrations of

Parts of the Sampling Date of marine soil samples taken Species Cs‐134 + Cs‐137 from these sampling points body measured* Point Catch (10 m in depth) have not (Bq/kg‐wet) been measured yet. Swimming crab (Large) muscle 0.704 ・In a survey of environmental samples Swimming crab muscle 0.444 conducted prior to the (Middle) extraction of marine Swimming crab (Small) muscle 1.52 organisms, an investigation Sand crab whole body South side, 0.814 was conducted in lines from Aug 3, 2013 Cocktail shrimp whole body off the estuary 4.90 the estuary of the river out to sea. Upon obtaining marine Cocktail shrimp muscle 1.10 organisms, the concentration Cocktail shrimp other than muscle 8.38 of radioactive cesium at the Grass shrimps whole body 2.30 midpoint between two

Cocktail shrimp whole body 4.11 points (same depth at the estuary of the river) was Cocktail shrimp whole body 1.16 measured, yielding the Cocktail shrimp muscle 0.971 following: Cocktail shrimp other than muscle 5.57 Cs137：2440 Bq/kg-dry North side, Cs-134：1213 Bq/kg-dry Swimming crab muscle Aug 3, 2013 1.81 off the estuary Paradorippe granulata whole body 15.1

Philyransdyactyla whole body 2.47

Hermit crabs whole body 3.42

Table 3-2 Concentration of Radioactive Cesium in Benthos Obtained within Twenty Kilometers of the Daiichi Nuclear Power Station in October 2013

Taxonomical group 134Cs + 137Cs (Bq/kg-wet)

Polycahaete Glyceridae N.D. Eunicidae Flabelligeridae Terebellidae

Ophelia bicornis N.D. Polynoidae Kinberg

Crustacea Crangonidae Paradorippe granulata Philyra syndactyla

Asteroidea Luidiidae Asterias amurensis N.D.

Figure 3-3 Survey points for radioactivity in benthos off the coast of Fukushima Prefecture in October 2013 * The concentration of radioactive cesium in the marine soil at the survey site: 288 Bq/kg-dry

3-1-3 Research on Ecology of Fish Species and the Timing of Radionuclide Transfer Pacific cod, which were collected between March 2011 and October 2014 off the coast of Fukushima, were divided into 2009, 2010, 2011, 2012 and 2013 birth year classes to examine changes in radioactive cesium concentrations via time series. Fish in the earlier birth year classes displayed higher concentrations of radioactive cesium, while those in the 2011 or later year classes was lower than for the 2010 and prior year classes. In previous studies, it has been discovered that Pacific cod over one year old migrate to shallow sea areas in low-water temperature seasons. In this study, the 2011 or later year classes took in little radioactive cesium in the 2012 low-water-temperature season, and the 2009 and 2010 year classes did not show any increase in their radioactive cesium concentrations during low-water-temperature season (Figure 3-4). Thus, it was inferred that Pacific cod primarily from the 2010 and prior year-classes ingested, in the course of migrating into shallow sea areas, radioactive cesium found in seawater with high concentrations of radioactive cesium that had been discharged into the water immediately after the accident. On the other hand, since the concentration of radioactive cesium in seawater found even in shallow sea areas in and after 2012 had been declining, it has been inferred that the volume of radioactive cesium ingested by Pacific cod was low.

Figure 3-4 Chronological Trend of Radioactive Cesium Concentration within Pacific cod Sampled offshore Fukushima

Also, there is a study that examines changes in radioactive cesium concentrations by olive flounder’s birth year groups (year classes). In this monitoring study which began in November 2011, the greatest reading among the 2009 and 2010 year classes was about 100 Bq/kg, while for the 2011 and 2012 year classes readings were mostly below detection limit (Figure 3-5). Moreover, research has been carried out on the relationship between total length and radioactive cesium concentrations. Samples were taken from individuals of 300mm-400mm in total length, whose feeding habits are similar to those of adult fish and habitat areas largely overlap with those of adult fish. The maximum concentration of samples in the 2010 year class was 120 Bq/kg, while concentrations were mostly in the 0-70 Bq/kg range; but in the 2011 year class, none of the samples exceeded 10 Bq/kg (Figure 3-6). Hence it is thought that, for olive flounders as well, little intake of radioactive cesium took place in Sendai Bay in and after the winter of 2012.

140 ） 2009YC

wet 120 ‐ 2010YC ）

Bq/kg 100

137; ‐ 80 Cs

+ on of cesium cesium on of

60 134 ‐

Cs 40 Concentrati

Cs-134 + Cs-137; Bq/kg-wet Cs-137; + Cs-134 （ 20

0 セシウム濃度（ 0 100 200 300 400 500 600 700 800 900 1000 事故後経過日数（日）Days from 11 March 2011

） 20 wet

‐ 2011YC

） 2011YC(ND) Bq/kg

15 2012YC 137; ‐

Cs 2012YC(ND)

+ 10 on of cesium cesium on of

134 ‐ Cs

5 Concentrati

Cs-134 + Cs-137; Bq/kg-wet Cs-137; + Cs-134 （ 0 セシウム濃度（ 0 100 200 300 400 500 600 700 800 900 1000 Days from 11 March 2011 事故後経過日数（日）

Figure 3-5 Olive flounder, by Birth Year Class: Relationship between the Number of Days Elapsed since the Fukushima Daiichi NPS accident and Radioactive Cesium Concentration

When comparing ） 140 2005‐2007YC wet individuals of 300-400 mm ‐ 120 2008YC

2009YC in length, the readings ） Bq/kg

100 2010YC 2011YC from 2010 year class 137;

‐ 2011YC(ND)

Cs 80 mostly ranged in 0-70

+ 2012YC

2012YC(ND) Bq/kg and displayed 120

134 60 ‐

Cs Bq/kg at the maximum, 40 while in the 2011 year

20 class, none of the samples

Concentration of cesium (Cs-134 + Cs-137; Bq/kg-wet

セシウム濃度（ 0 exceeded 10 Bq/kg. 0 100 200 300 400 500 600 700 800 全長Total(mm) Length (mm) Figure 3-6 Relationship between the Length of and Radioactive Cesium Concentration in Olive flounder, by Birth Year Class

3-1-4 Conclusion and Future Research This survey revealed that the concentration of radioactive cesium in benthos, a prey for other species was lower than the concentration of radioactive cesium found in the marine soil where these organisms inhabited. As the concentration of radioactive cesium in fishery products steadily declines, the pace at which this decline was occurring was slowing for certain species of demersal fish. Therefore, it is though that demersal fish take in radioactive cesium from contaminated marine sediments through the benthic food web [64, 65]. In addition, Ono et al. (2015) analyzed marine soil obtained in the summer of 2012 off the coast of Fukushima Prefecture and reported that the bulk of radioactive cesium found in marine soil (86.1 to 97.6%) existed in a form that either prevents, or renders difficult, ingestion by marine organisms [66]. Accordingly, it is thought that the amount of radioactive cesium found in marine soil moved to demersal fish through benthos, a prey was very low. On the other hand, while Pacific cod and olive flounder constitute fish species in which high concentrations of radioactive cesium have been found across a relatively wide area of the sea, an analysis of concentrations of radioactive cesium by year class clearly revealed that levels of the concentration of radioactive cesium have been low in these fish species from the 2011 and later year classes. It is believed that this is due to the fact that the amount of radioactive cesium taken by specimens born in 2011 or later was low since such fish were not exposed to seawater containing extraordinarily high radioactive cesium that was present immediately after the accident. The concentration of radioactive cesium in marine fish species is expected to decline as the number of fish born after the accident increases. As was seen in Chapter 3 of Part One, concentrations of radioactive cesium in Pacific cod and olive flounder has been declining since FY2014 in areas inclusive of the waters off the coast of Fukushima, and no cases in which limits were exceeded were observed. Although ordinary monitoring inspection conducted by local governments does not include the measurement of age, it is estimated that most of the caught Pacific cod were between 1 and 2 years (North Pacific population) [67] and the olive flounders were 1 year plus or 2 years plus (North Pacific population) [67]. In other words, the decline in concentrations of radioactive cesium in Pacific cod and olive flounder observed through monitoring inspection is thought to be attributable not just to the decline in the concentration of radioactive cesium in seawater but also to the fact that fish born after the earthquake have come to comprise a major part of the populations of caught Pacific cod and olive flounder. Further research on transfer routes of radioactive materials will make it possible to provide fishermen and consumers with the specific causes of fishery products contamination and predictions in terms of reductions in contamination.

Chapter 2. Urgent Research on the Cause of Contamination of Highly Contaminated Fish (Fat greenling) j

As seen in Part One, Chapter 2, radioactive cesium concentrations in fishery products are generally in decline. At the same time, samples of fat greenlings, Hexagrammos otakii, contaminated with high concentrations of radioactive cesium were caught approximately twenty kilometers north of the Fukushima Daiichi NPS in August 2012, a little over a year after the accident occurred. In order to provide scientifically-grounded explanations of the causes of the emergence of these highly contaminated fish to fishermen and consumers, the Fisheries Agency, together with the Japan Fisheries Research and Education Agency (presently known as the Japan Fisheries and Education Agency) and other bodies, engaged in research to clarify the pathways and causes of contamination affecting highly contaminated fish. This chapter explains the results of this research [68; 69].

3-2-1 Frequency of Appearance of Highly Contaminated Fat greenlings Among the fat greenlings taken in the Fukushima sea zone between April 2012 and February 2013 emerged the aforementioned highly-contaminated sample, in which radioactive cesium was detected at the level of 25,800 Bq/kg-wet. This differed substantially from other samples and was on the same level as samples taken from the Fukushima Daiichi NPS port (Figure 3-7, left graph). Excluding this sample from all fat greenlings samples taken in the Fukushima sea zone from April 2012 to February 2013, and assuming a frequency distribution approximated by a log-normal distribution, the probability that a sample exceeding 10,000 Bq/kg-wet will appear is less than 1/50,000 (Figure 3-7, right graph). Based on these facts, the highly contaminated sample taken in August 2012 was considered to have passed through an environment different from that experienced by all other samples taken in the Fukushima sea zone up until that point. The sample was conjectured to have been contaminated either within the power station port or in an area very close to the station itself.

Figure 3-7 Radioactive Cesium Concentrations within Fat greenlings offshore Fukushima

j Published in English online scientific journal “Scientific Reports” on October 31, 2014.

3-2-2 Determining the Time of Contamination through Autoradiography Experiment β-rays were measured in the otolith of fat greenlings caught approx. twenty kilometers north of the Fukushima Daiichi NPS and within the Fukushima Daiichi NPS port, as well as in brassblotched rockfish, Sebastes pachycephalis, in the Fukushima Daiichi NPS port. From these measurements, a proportional relationship was confirmed to exist between radioactive cesium-137 in muscle material and β-rays in the otolith (Figure 3-8, left graph). Further, through analysis of the β-rays from the otolith of brassblotched rockfish in the Fukushima Daiichi NPS port, it was learned that there is a deviation in the β-rays’ emission location (Figure 3-8, right graph). Additionally, analysis of the relationship between the high-concentration fat greenling’s otolith rings and an imaging plate (IP) of the otolith (Figure 3-9) revealed that primary location of the β-rays’ emission corresponded to spring/summer 2011, and hence this sample was judged to have been contaminated shortly after the Fukushima Daiichi NPS accident through exposure to highly-contaminated waters.

Figure 3-8 Analysis of the Fukushima Daiichi NPS port Brassblotched rockfish Otolith

Figure 3-9 Analysis of the Highly-Contaminated Fat greenling’s Otolith

3-2-3 Study on the Migration Ecology and Habitat History of the Fat greenling Based on the results of past capture-and-recapture studies conducted off the coast of Fukushima Prefecture, it has been reported that fat greenlings migrate up to 27 kilometers, although most samples migrated between 0 and 15 km (avg. 8 km) [70]. The water off the estuary of the Ota River, where highly-contaminated specimens were caught in August 2012, is located approximately 20 kilometers away from the port of the nuclear power plant and within above mentioned migratory range. To learn more about the migratory pattern of the fat greenling, mark-and-release surveys were conducted in February 2013 and between January and February 2014 off the coast of Soma (90 specimens; total length between 200 and 533 millimeters) and in Sendai Bay (111 specimens; total length between 238 and 460 millimeters). Nine specimens have so far been recaptured with the distance between the point of release and the point of recapture being between 2.2 and 33.9 kilometers (average 11.2 kilometers), which is in line with previous results above mentioned (as of the end of September 2016). To determine whether the highly-contaminated fat greenling displayed a strong freshwater influence in its habitat history, sample taken in the Iwaki sea zone and sample taken at the estuary of the Ota River were compared by otolith Sr/Ca ratio, which shows a low value in low-salinity environment. However, no strong signs of freshwater influence were observed in the highly-contaminated sample.

3-2-4 Estimate of Contamination Source by Contamination Model for the Fat greenling Sample In order to conjecture the contamination source of the highly-contaminated fat greenling sample, a simulation model was constructed for radioactive cesium concentrations within a fish’s body, based on cesium levels in the water of the Fukushima Daiichi NPS port and historical parameters (coefficient of intake from seawater: 0.2; biological half-life: 100 days; food intake: 1 % of body weight). This simulation model was used to perform a simulation using multiple condition settings for contamination source and migration route. Contamination sources were set as high-, mid-, and low-concentration values based on the range of concentrations within the Fukushima Daiichi NPS port. Migration routes were set as a) staying within the port, and b) moving out of the port area after August 2011. Through this simulation model, radioactive cesium concentrations frequently reoccurred on the level of the >10,000 Bq/kg fat greenling taken within the port between December 2012 and February 2013. Further, when low-concentration seawater within the port was set as the contamination source, the result of calculations on the individual that migrated out of the port after August 2011 produced radioactive cesium concentrations close to those of the highly-contaminated sample found at the estuary of the Ota River. These results, in combination with the results from the otolith analysis, suggest that the sample was strongly affected by highly-contaminated water within the Fukushima Daiichi NPS port in the initial period after the accident (Figure 3-10).

Figure 3-10 Simulation Model of Radioactive Cesium Concentrations within Fat greenling

3-2-5 Conclusion and Measures The highly contaminated sample taken in August 2012 is considered to have been heavily affected shortly after the Fukushima Daiichi NPS accident by highly contaminated water in the Fukushima Daiichi NPS port, then to have remained at high concentrations through the ingestion of contaminated prey. This sample is then considered to have migrated at some point to the place at which it was taken. Five years have passed since the Fukushima Daiichi NPS accident, and situation of affected ocean areas, including waters off Fukushima (except for the Fukushima Daiichi NPS port interior), has improved in terms of contamination. TEPCO is engaged in efforts to stop the spread of contaminated marine organisms by installing nets at the mouth of the port and exterminating marine organisms within the port. These measures are taken thoroughly to preclude the occurrence of such highly-contaminated samples.

Chapter 3. Evaluation of Radioactive Cesium Transfer from Marine Soil to Marine Organisms based on a Rearing Experiments

As was mentioned in 2-3-2, 10 to 1,000 Bq/kg of radioactive cesium was found in the marine soil within 20 kilometers of the Fukushima Daiichi Nuclear Power Station immediately after the accident occurred. The concentration of radioactive cesium in the marine soil has since declined due to the dispersion of marine soil in a horizontal direction and the settling and deposition of uncontaminated sedimentation, such that the concentration of radioactive cesium now ranges between 10 and several hundred Bq/kg [64, 65]. While it is thought that the impact on organisms in the marine soil will decline from year to year, there are concerns that such radioactive cesium could be ingested by fish through benthic food web. As mentioned in 3-1-4, it is thought that the amount of radioactive cesium moving from marine soil to demersal fish and other marine organisms through the consumption of prey is very low but evaluations and examinations based on scientific grounds concerning the movement of radioactive cesium from the marine soil into fishery products will still need to be conducted in order to stabilize the fisheries industry in Fukushima Prefecture. In this chapter, we will report on the results of experimental rearing carried out by the Japan Fisheries Research and Education Agency (FRA) jointly with relevant organizations to evaluate radioactive cesium moving from the marine soil into marine organisms [71].

3-3-1 Outline of the Preparatory Rearing Experiment with Benthos and Fish Korean lugworms, Perinereis aibuhitensis (benthos) were reared for 84 days and olive flounder, Paralichthys olivaceus (demersal, two-year-old fish; total lengths 266 - 409 mm) and Japanese black porgy, Acanthopagrus schlegelii (pelagic, one-year-old fish; total lengths 85 - 156 mm) for 49 days each in tanks containing marine soil collected from areas off the Fukushima Prefecture shore(near the Daiichi NPS and off the coasts of Hirono and Yotsukura) and seawater taken near Onahama, Fukushima Prefecture (free flowing). Every few days the organisms, marine soil, rearing seawater, and seawater were sampled from each tank to measure their concentrations of cesium-137. In addition, as an experiment to contrast the free-flowing water experiment, Korean lugworms were raised in a still-water environment for two weeks beginning with the 77th day after rearing.

3-3-2 Results for the Korean lugworms For the free-flowing-water rearing experiment (three marine soil types, two tanks each), concentrations of cesium-137 in the marine soil and rearing seawater were largely constant. Concentrations of cesium-137 in the lugworms increased slightly in each tank shortly after the experiment began. From the 21st day of the experiment, the concentrations began to stabilize and matched the rankings of concentrations for the marine soil (Table 3-3). In the still-water-tank experiment (two types of marine soil), the concentrations of cesium-137 in the soil of the still-water tank did not show any significant fluctuations in comparison with the free-flowing-water tanks. However, rising concentrations were observed in the lugworms after two weeks, as were rising concentrations in the breeding water of the still-water tank (Table 3-4). This suggests that cultivation in a still-water environment might have caused the concentration of cesium-137 re-dissolved from the marine soil to increase

89 in the rearing water, thereby causing the concentration of cesium-137 in Korean lugworms to rise.

Table 3-3 Results of the Korean lugworm Rearing Experiment Marine soil Korean lugworms Rearing seawater concentration (n=16) (n=10) (n=15 or 16) mBq/kg Bq/kg-wet Bq/kg-wet (Average after (Average during rearing (Average during rearing period) Sampling location 21st day period) [concentration

Southern side of sea area near TEPCO’s Fukushima ① 341±38.8 11.7±5.79 52.2±21.1

Daiichi NPS (37°25’N, 141°02’E) ② 333±42.3 11.4±2.54 86.5±36.9 ① 136±7.53 5.15±2.48 22.3±6.29 Offshore area of Hirono (37°16’N, 141°02’E)

② 162±27.5 7.48±3.21 24.9±7.52 ① 88.7±8.46 4.93±3.62 27.6±25.4 Offshore area of Yotsukura (37°05’N, 140°59’E)

② 67.8±6.04 3.88±2.59 20.3±7.26

Table 3-4 Results of the Still-Water-Tank Breeding Experiment Breeding seawater mBq/kg Korean lugworms (2 weeks later) Sampling location Bq/kg-wet Southern side of sea area near TEPCO’s Fukushima Daiichi NPS 42.9 2,480 (37°25’N, 141°02’E) Offshore area of Yotsukura (37°05’N, 23.0 600 140°59’E)

3-3-3 Results for the Olive flounder and Japanese Black porgy Concentrations of cesium-137 in the marine soil were largely constant in the five-ton tanks (tank containing marine near the nuclear power station and tank containing offshore marine soil from Yotsukura) in which the olive flounder and Japanese black porgy were raised. In both tanks, concentrations in the rearing seawater rose immediately after the experiment began but then gradually declined before eventually fluctuating around 30 mBq/kg in the case of the NPS tank and 20 mBq/kg in the case of the Yotsukura tank. These levels are equal to or slightly higher than the current values for seawater in the coastal areas of Fukushima Prefecture. Concentrations of cesium-137 in olive flounder showed no clear increases during the rearing period (start of experiment: around 1 Bq/kg-wet → after experiment: 0.5 to 2.5 Bq/kg-wet). In the case of Japanese black porgy, a cesium-137 reading of 0.680 Bq/kg-wet was detected in the NPS tank on the 14th day, followed by a reading of 0.984 Bq/kg-wet in the Yotsukura tank on the 21st day. However, subsequently, no clear increases

90 in concentration were observed in either tank (start of experiment: N.D. → after experiment: no more than 1 Bq/kg-wet). From these results, it is thought that the amount of cesium-137 that migrated from the marine soil and breeding seawater to the bodies of the olive flounder and Japanese black porgy was negligible or very small.

3-3-4 On-site Rearing Experiment Cages enclosing one-year-old olive flounder were set up in the Tomioka fishing port and Onahama fishing port at sites located 9.4 kilometers and 55 kilometers, respectively, south of the Fukushima Daiichi NPS, whereupon a rearing experiment was conducted from June 26 to August 28, 2014 (Figure 3-11).

Figure 3-11 Cages set up in the Tomioka Fishing Port.

The concentrations of cesium-137 found in the bottom-layer seawater collected from the sites where these cages were set up in the Tomioka fishing port and Onahama fishing port (water was collected three times at approximately one-month intervals during the rearing period) were between 110 and 120 mBq/L at the Tomioka fishing port and between 16 and 19 mBq/L at the Onahama fishing port. Concentrations of cesium-137 found in the marine soil layer (0-1 centimeters) likewise collected from the sites where these cages were set up at the time they were set up measured 170 Bq/kg-dry at the Tomioka fishing port and 450Bq/kg-dry at Onahama fishing port. Concentrations of cesium-137 found in the bodies of olive flounder test specimens (excluding internal organs) rose for approximately two months measured between 0.91 and 2.1 Bq/kg at the Tomioka fishing port and between 0.92 and 1.4 Bq/kg at Onahama fishing port. If we take into account the fact that olive flounder test specimens contained approximately 0.74 to 0.97 Bq/kg of cesium-137 at the beginning of this experiment, then we can surmise that almost no radioactive cesium transfer was occurred from contaminated marine soil into olive flounder specimens at either testing site (Figure 3-12).

found of Cs-137 Concentration in bodies (Bq/kg-wet) Initial Tomioka Onahama

values Fishing Port Fishing Port

Figure 3-12 Cage-testing Results White circles denote the concentration of cesium-137 while black dots correspond to samples that yielded no detectable concentration readings and that were thus below minimum detection limits.

3-3-5 Outline of Rearing Experiment to evaluate Radioactive Cesium Transfer from Contaminated Marine Soil to Benthos and Demersal Fish The experiment to rear marine organisms in water tanks lined with marine soil collected from near the Fukushima Daiichi NPS, off the coasts of Hirono and Yotsukura, and Iwasawa Beach was conducted in 2015 to evaluate radioactive cesium moving from the marine soil off the coast of Fukushima Prefecture into marine organisms through the consumption of prey. Five-ton water tanks were lined to a depth of about 10 centimeters with marine soil collected from multiple sites after the soil was stirred well to achieve a generally uniform level of concentration. For rearing water, filtered seawater drawn from off the coast of Onahama in Fukushima Prefecture was used (raw seawater). By conducting a rearing experiment with free-flowing water, an experiment for which an attempt was made to recreate the environment off the coast of Fukushima Prefecture was conducted. For test fish, fat greenlings obtained from Miyako Bay, Iwate Prefecture (total length between 232 and 520 millimeters), were used and reared for 70 days. In addition, Korean lugworm, and Grapsid crab, Hemigrapsus penicillatus, benthos constituting prey to be fed to farmed fish, were also bred in separate water tanks lined with the same marine soil. Using prey reared in advance for at least 21 days in order to be fed to fat greenlings, the rearing experiment was conducted by establishing a Grapsid crab feeding zone and Korean lugworm feeding zone within the same water tank.

(Bq/kg-wet) Cs-137 in benthos of Concentration

Below (Bq/kg-dry) Cs-137 in sediment of Concentration minimum detection limits Rearing days Figure 3-13 Temporal trends of Cs-137 Concentrations in Benthos (circle) and Marine Soil (square) through the Benthic Food Web in Rearing Tanks Concentrations of Cs-137 are presented for marine soil along the top of the figure and for benthos along the bottom of the figure.

3-3-6 Results and a Review of the Water-Tank Rearing Experiment The concentration of cesium-137 in marine soil at the start of the rearing experiment was 242 Bq/kg-wet. While it was recognized that the concentration of cesium-137 in marine soil was gradually declining with the passage of time, there were no significant changes, such that the average value ± standard deviation during the rearing period was 166 ± 24.8 Bq/kg-wet (n=11) for the water tank in which fat greenlings were being raised, 169 ± 35.5 Bq/kg-wet (n= 14) for the water tank in which Korean lugworms were being raised, and 148 ± 34.0 Bq/kg-wet (n = 14) for the rearing water used for Grapsid crab (Figure 3-13, 3-14). The average value ± standard deviation of the concentration of cesium-137 contained in rearing water during the rearing period was 49.1 ± 26.7 mBq/kg for the water tank in which fat greenlings were being raised (n=14; same since the rearing water was being shared between the water tank in which fat greenlings were being bred and the water tank in which benthos were being bred) and contained in raw seawater was 15.0 ± 7.74 mBq/kg (n=13; specimens for the forty-ninth day were missing). The concentration of cesium-137 in rearing water has been more or less the same as or slightly higher than that of seawater along the coast of Fukushima Prefecture since 2014 [72]. The concentration of cesium-137 in the marine soil during the rearing period showed signs of a slight decline. On the other hand, the cesium-137 that had eluted from the marine soil in water tanks used for the rearing of fat greenlings is thought to have caused the concentration of rearing water to rise since the concentration of cesium-137 in the rearing water found in the water tank used for the rearing of fat greenlings and lined with marine soil is slightly higher than it is for raw seawater. The concentration of cesium-137 in Korean lugworm specimens during the feeding period was measured to be a little high at 44.9 Bq/kg-wet on the twenty-first day of rearing and 14.8 Bq/kg-wet on the sixty-third day of rearing. At all other times, it generally stayed at around 5 Bq/kg-wet (Figure 3-13). The sporadically high

93 values are thought to have been caused in part by the radioactive cesium found in the marine soil that was ingested into the bodies of the Korean lugworm specimens. The concentration of cesium-137 found in Grapsid crab specimens did not change significantly and stayed at or below 3 Bq/kg-wet (Figure 3-13). Since food to which cesium-137 had been added was not fed to either prey, it is thought that the increase in the concentration of cesium-137 is attributable to the rearing water or the marine soil. The average value ± standard deviation of the concentration of cesium-137 in benthos during the feeding period was 8.54 ± 12.6 Bq/kg-wet (n=11) in the Korean lugworm specimens and 2.06 ± 0.566 Bq/kg-wet (n=11) in Grapsid crab specimens (Figure 3-13). The ratio of this concentration to the concentration of cesium-137 (242 Bq/kg-wet) found in the marine soil at the start of rearing was approximately 1:30 for the Korean lugworm specimens and approximately 1:120 for the Grapsid crab specimens.

Marine soil in water tanks for rearing demersal fish

Grapsid crab ‐ feeding section (with marine soil) Grapsis crab ‐ feeding section (without marine soil) wet)

Korean lugworm ‐ feeding section (with marine soil) ‐ Korean lugworm ‐ feeding section (without marine soil) Non‐contaminated Korean lugworm ‐ feeding section (control zone; without marine soil)

(Bq/kg

soil

marine

) 137 Maximum value of measurement data by ‐ specimen : Grapsid crab-feeding zone (with Cs

-wet marine soil) → 1.65Bq/kg-wet g of

k / q B (

reenlin Concentration of Cs-137 in fat g Concentration Minimum detection limits

Rearing days

Figure 3-14 Temporal Tends of Cs-137 Concentrations in Fat greenlings (circle) and Marine Soil (square) in Rearing Tanks Each week, a few individuals were obtained from each testing zone. Specimen of muscle tissue was taken from individual fat greenling. Plotted circles and corresponding error bars in the figure denote arithmetical average values and standard deviations calculated based on the measurement values obtained for multiple muscle specimens.

The concentration of cesium-137 in fat greenlings was shown to be increasing slightly in each testing section since the start of the rearing experiment. However, no significant changes were detected, such that the concentration of cesium-137 generally stayed at or below 1 Bq/kg-wet (Figure 3-13). The average ± standard deviation of the concentration of cesium-137 in fat greenlings were 0.742 ± 0.333 Bq/kg-wet (n=33) in the Grapsid crab feeding zone and 0.770 ± 0.311 Bq/kg-wet (n=34) in the Korean lugworm feeding section. The highest value for the concentration of cesium-137 that was obtained was the 1.65 Bq/kg-wet reading that was obtained for specimens extracted on the seventieth day from the testing section in which Grapsid crab was

94 being fed. The ratio of this concentration to the concentration of cesium-137 found in the marine soil at the time of the start of rearing (242 Bq/kg-wet) was approximately 1:150.

3-3-7 Review and Outlook The site where marine soil was obtained for preparatory experiments pertaining to the rearing of benthos is a coastal area south of the Fukushima Daiichi NPS that has been verified as having relatively high concentrations among areas off the present-day coast of Fukushima Prefecture. In the case of Korean lugworms, a species of benthos that fish feed on, it was suggested that, although radioactive cesium in marine soil does influence concentrations in the lugworms, the transfer rate is not very high (the ratio of concentration [lugworm/marine soil] even in the rearing experiment under a still-water condition that is considered unrealistic as an actual marine environment (the result that was conducted with free-flowing water resembling the actual environment was between 1/20 and 1/40). Moreover, in the rearing experiment for olive founder and Japanese black porgy that used the same marine soil, there was almost no increase in cesium-137 concentrations in the raised fish. It is believed that the Tomioka fishing port where the on-site rearing experiment was conducted and the coastal area to the south of the Fukushima Daiichi NPS from where marine soil for the water-tank rearing experiment was obtained were highly affected immediately after the accident in 2011 by contaminated water that contained high concentrations of radioactive cesium [73; 74; 75]. Concentrations of radioactive cesium in marine organisms obtained in these areas were slightly higher than for marine organisms obtained in other areas of the sea [65]. An on-site rearing experiment conducted in a sea area off the coast of Fukushima Prefecture with a relatively high level of contamination and a water tank-rearing experiment designed to recreate the same environment indicated that the amount of radioactive cesium that transferred into marine organisms from the marine soil was negligible. Based on the results of these rearing experiments, it is believed that there is a very low chance that the concentration of radioactive cesium in marine organisms living off the coast of Fukushima Prefecture will exceed the standard limit of 100 Bq/kg-wet for general foods through the continued ingestion of radioactive cesium found in the marine soil.

Chapter 4. Radioactive Material Concentrations and Territories of Fish Species

Following the accident at TEPCO’s Fukushima Daiichi NPS, olive flounder samples containing radioactive cesium exceeding the standard limit for general foods (100 Bq/kg) were found in a comparatively large area. The following describes a simulation of changes in cesium concentration in olive flounder using time series variation data for concentrations of cesium (Cs-134 + Cs-137) in seawater and prey organisms that were obtained from monitoring conducted heretofore [71]. (Recalculated by Matsuno scheme)

(1) Simulation Outline The results of the simulation suggest the following two characteristics (Figure 3-15 (c)).

(i) Differences in radioactive cesium concentrations were observed between year classes prior to the accident (2009, 2010 YC) and year classes following the accident (2011, 2012 YC). No significant differences were observed between the year classes prior to the accident. The peak value was 286 Bq/kg-wet when seawater having a moderate concentration was experienced (peaking 43 days after the accident) and 109 Bq/kg-wet when no cesium from seawater was inputted in the early stage (peaking 184 days after the accident). However, the cesium concentrations for the year classes coming after the accident (2011 and 2012) were lower than those before the accident, with the peak values being 32 Bq/kg-wet and 8 Bq/kg-wet, respectively. This difference in cesium concentrations depending on year class was also seen in data from actual measurements. (ii) The difference in the first 100-day contamination history remained as the difference in cesium concentrations in fish bodies one to two years following the accident. In particular, individuals that experienced seawater with a high concentration in the early stage had higher cesium concentrations than individuals that experienced moderate concentrations in the early period and individuals that were not affected by contaminated seawater. This means that the cesium concentration in the body is not necessary an expression of very recent contamination density alone; rather, it points to the possibility that, for olive flounder, the contamination history beginning immediately following the accident could be dragged out for a long period of time.

(2) Consideration and Outlook At the present time, radioactive cesium concentrations in olive flounder are declining across the board. Nonetheless, although infrequent, individuals that exceeded the limit for food products were even found in areas away from the coast of Fukushima Prefecture until FY2013. Consequently, restrictions on shipping and distribution were issued from Miyagi Prefecture to Ibaraki Prefecture. The simulation showed that, although individual variability exists, some individuals born prior to the accident that were affected by highly contaminated water continue to show effects for two years. Additionally, it is confirmed from a separately conducted survey of olive flounder migration patterns that the species’ area of migration is wide (although it is focused primarily on movement into the Sendai Bay, it actually extends from Aomori to Chiba Prefectures). In May of 2013, which was more than two years after the accident, samples exceeding the 100 Bq/kg limit were found off the coast of Miyagi Prefecture, despite the fact no radioactive cesium was detected in the seawater there. It is thought that the results of the simulation can help explain the cause of this phenomenon. Additionally, because most samples taken from future catches will have been born after the accident, it is estimated that the possibility of encountering samples that exceed the limit will continue to decrease.

- Time series variation of radioactive cesium in olive flounder by (a) seawater, (b) prey, and (c) year class. - 2009 YC shows changes for the first 100 days following the accident (1) when fish experience highly contaminated water (A + F), (2) when fish experience moderately contaminated water (B +F), and (3) when fish do not experience seawater containing cesium (C + F) (modification of Kurita et al[76].)

Figure 3-15 Simulation on Changes in Radioactive Cesium Concentrations within Olive flounder

(Simulation method)  For the concentration of radioactive cesium in seawater, the data set for Iwasawa coast (16 kilometers south of the Fukushima Daiichi NPS; (publicly disclosed through the TEPCO website), was used for the actual value data. It was determined that values equivalent to 1/10 of this actual value data would constitute data for moderately contaminated seawater. ・ When fish experience highly contaminated seawater (A + F): when Iwasawa’s monitoring data were applied up to 100 days following the accident (moderately contaminated seawater is applied after 100 days) ・ When fish do not experience seawater containing cesium (C + F): When a seawater cesium concentration of 0 Bq/L is applied up to 100 days following the accident (moderately contaminated seawater is applied after 100 days)

 For prey organisms, time series data for mysids and small fish (average values for anchovy and Japanese sandlance) were used [77]. It was assumed that an olive flounder feeds on mysids for its first

year and small fish thereafter. The amount of radioactive cesium ingested per day from seawater by a fish weighing 1 kilogram was set to 0.1 times the concentration of radioactive cesium in seawater. The amount of radioactive cesium ingested per day from feed was set to 0.01 times the concentration of radioactive cesium in feed (amount ingested per day 0.02; absorption rate 0.5). The biological half-life was set at 104 days.

Chapter 5. Quantitative Evaluation of Contamination Risk from Radioactive Material in Fishery Productsk The effects of the accident at the Fukushima Daiichi NPS were enormous, and it is thought that various living beings are suffering extensive and long-term consequences from radioactive material that released from the plant. The risk of radioactive contamination of fishery products is a matter of serious concern for consumers. Thus, it is believed that conducting a quantitative evaluation to determine which species are safe or hazardous and where those species are found will make a significant contribution to the future revitalization of fishery activity. This chapter presents a summary of a “quantitative evaluation of contamination risk from radioactive material in fishery products” that was conducted by the Japan Fisheries Research and Education Agency and othersl.

3-5-1. Means of Predicting the Risk of Contamination from Radioactive Materials in Fishery Products (1) Method for Predicting Risk The evaluation calculated risk for 68 fish species using the results of concentration tests for radioactive cesium (Cs-134 and Cs-137) in food that were conducted between April 2011 and December 2014 and made public by the Ministry of Health, Labour and Welfarem. “Risk” was evaluated as the probability that the sum of Cs-134 and Cs-137 would exceed 100 Bq/kg on April 1, 2015. Using the Weibull distribution (a probability model used in life-span modeling), this probability was evaluated by estimating parameters (degree of early-stage contamination, ecological half-life, and Weibull coefficient) based on maximum likelihood estimation that took detection limits into account. At the same time, a method called the “random effects model” was used to supplement missing values and data deficiencies. Parameter estimations were made by prefecture (Aomori, Iwate, Miyagi, Fukushima, Ibaraki, and Chiba) and by fish species.

(2) Results Risk was evaluated by applying models to data for each of the targeted fish species and prefectures. Rapid decreases in cesium concentrations were observed. Figure 3-15 provides a list of important species of the 68 species that were targeted for evaluation. For comparison, results for rockfish (Sebastes cheni), ocellate spot

k Dr. Hiroshi Okamura, Resources Management Group Leader, Research Center for Fisheries Management, National Research Institute of Fisheries Science, National Fisheries Agency, cooperated with this analysis and the writing of this chapter. l Implemented by the Japan Fisheries Research and Education Agency and the Institute of Statistical Mathematics. Some results were announced by the Japanese Society of Fisheries Science in 2015. m With the exception of this chapter, data announced by the Fisheries Agency are used in this report.

98 skate, and olive flounder of Fukushima Prefecture, which continue to be subject to restrictions on shipping and distribution, are also provided. For almost all fish species, the probability that radioactive cesium concentration will exceed 100 Bq/kg on April 1, 2015, is effectively zero (Table3-5, Figure 3-16).

Table 3-5 Probability of Exceeding 100 Bq/kg as of April 1, 2015, based on Model Analysis Prefecture Species Pr(134Cs + 137Cs > 100) Aomori Japanese amberjack 1.06×10-292 Scallop 3.00×10-111 Chub mackerel 0 Giant Pacific octopus 0 Chum salmon 9.36×10-139 Alaska pollock 2.63×10-160 Japanese flying squid 0 Japanese amberjack 0 Iwate Scallop 0 Common sea squirt 0 Chub mackerel 0 Giant Pacific octopus 0 Pacific saury 0 Chum salmon 0 Alaska pollock 1.07×10-44 Japanese flying squid 0 Chestnut octopus 0 Spear squid 0 Miyagi Shortfin mako shark 1.34×10-65 Albacore 0 Japanese amberjack 0 Scallop 0 Skipjack tuna 0 Common sea squirt 0 Pacific oyster 0 Chub mackerel 0 Bigeye tuna 0 Swordfish 0 Giant Pacific octopus 0 Salmon shark 0 Pacific saury 1.06×10-44 Chum salmon 0 Alaska pollock 0 Japanese flying squid 0

Spear squid 0 0 Blue shark

Fukushima Japanese amberjack 2.05×10-18 Common octopus 3.03×10-29 Chub mackerel 0 Giant Pacific octopus 7.33×10-122 Chum salmon 0 Alaska pollock 4.18×10-29 Japanese flying squid 6.80×10-97 Chestnut octopus 7.25×10-126 Spear squid 8.42×10-50

Rockfish (Sebastes cheni) 0.039 Species those are still subject to -5 Ocellate spot skate 6.59×10 restrictions on shipping and -9 Olive flounder 1.14×10 distribution as of the end of Ibaraki Japanese amberjack 0 March 2015 Common octopus 0 Chub mackerel 0 Alaska pollock 0 Japanese flying squid 0 Chestnut octopus 0 Spear squid 0 Chiba Albacore 0 Japanese amberjack 0 Skipjack tuna 3.33×10-103 Yellowfin tuna 0 Chub mackerel 0 Bigeye tuna 0 Pacific saury 0 Japanese flying squid 0 Spear squid 0

Note: Values of less than 10-300 are considered to be “0.”

100

Japanese buri:amberjack Iwate (Iwate) Cesium concentration (Bq/kg) Cesium concentration 0 5 10 15 20

0 200 400 600 800 1200

Days

Ocellatekomonkasube: spot skate (Fukushima) Fukushima Cesium concentration (Bq/kg) Cesium concentration 0 100 300 500 700

0 200 400 600 800 1200

Days

Figure 3-16 Decrease in Radioactive Cesium Concentrations within Japanese amberjack of Iwate Prefecture and Ocellate spot skate of Fukushima Prefecture The red dots show measured values for Cs-137 and the black dots show measured values for Cs-134. The red and black vertical lines show detection limit data. The red dotted line and black line are predictions of average values based on the model.

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3-5-2. Change in the Probability of the Emergence of Concentrations of Radioactive Cesium in Pacific cod Over Time Distribution and shipping restrictions on the Pacific cod, a species for which the restrictions were ordered in every prefecture in the Tohoku region after the earthquake struck, were lifted for Ibaraki Prefecture in 2014 and Fukushima Prefecture in 2015. By indicating time-series changes in the probability that radioactive cesium will appear in Pacific cod by prefecture, the adequacy of the timing of the cancellation of these restrictions was examined. In every prefecture, the concentration of radioactive cesium in Pacific cod chronologically declined since the earthquake. In Aomori and Iwate Prefectures, the probability that the concentration of radioactive cesium in Pacific cod exceeded 50 Bq/kg was virtually zero in the second half of in 2013. The probability that the concentration of radioactive cesium exceeded the limit (100 Bq/kg) was virtually zero in Miyagi Prefecture by the second half of 2013 and in Ibaraki Prefecture by the first half of 2014. By the second half of 2014 in Fukushima Prefecture, the probability that the limit was exceeded was extremely low (Figure 3-17). Based on the above results, it can be concluded from a scientific perspective that distribution and shipping restrictions in Ibaraki and Fukushima Prefectures and elsewhere were lifted at an appropriate time.

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Aomori Iwate

Miyagi Fukushima

Changes in the probability of emergence of emergence Changes in the probability Ibaraki

Concentrations of Cs-134+137 (Bq/kg-wet, log)

Figure 3-17 Chronological Changes of the Probability that Concentrations of Radioactive Cesium will Appear within Pacific cod

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Chapter 6. Understanding the Mechanism by which Radioactive Cesium is Absorbed into the Soil

Section 2-3-2 explained how cesium in the ocean water sticks strongly to argilliferous on the ocean bottom, and how it is difficult for cesium stuck to the clay to be absorbed in the bodies of marine organisms. Research on the mechanism by which cesium sticks strongly to clay is making considerable progress on land, and a new n report was issued recently that sheds light on it [78; 79; 80; 81].

Vermiculite is a type of clay mineral that is commonly found in the soil of Fukushima Prefecture [82]. This study observed the structural changes that occur when cesium ions are absorbed onto vermiculite by using X-ray small angle scattering (an analytical method that irradiates a sample with X-rays and then uses the scattered X-rays at various intensities and in various directions depending on the structure of sample into a length scale of 1 to 1,000 nm). The result was revealed the following points: (i) The “Absorption” of cesium ions occurs at specific interlayers of the vermiculite as somewhat concentrated aggregations (Figure 3-18(a)). (ii) Clay layers separate as a result of the process of (i) above (Figure 3-18(b)). The reason for this is thought to be that when one cesium ion sticks between two layers, it becomes easier for other cesium ions to become stuck next to it, which thereby causes a large change in the local layer charge. Then, because the surfaces of the two separated layers now provide new places for the ions to attach, the vermiculite traps more and more cesium ions like “Domino Toppling”.

Figure 3-19 provides a schematic representation of the structural change in vermiculite that occurs as cesium ions are absorbed onto it.

n A joint research group comprised of Ryohei Motokawa (Assistant Principal Researcher) and Tsuyoshi Yaita (Unit Manager) of the Fukushima Environmental Safety Center and Quantum Beam Science Center, Japan Atomic Energy Agency; Hitoshi Endo (Assistant Professor) of the Institute of Materials Structure Science, High Energy Accelerator Research Organization (KEK); Shingo Yokoyama (Principal Research Scientist) of the Central Research Institute of Electric Power Industry; and Shotaro Nishitsuji (Assistant Professor) of the Yamagata University Faculty of Engineering. The report was published in the English-language online scientific journal Scientific Reports on October 10, 2014. It should be noted that Ryohei Motokawa (Assistant Principal Researcher) of the Japan Atomic Energy Agency assisted in the writing of the chapter.

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(b) Segmentation of the crystal domain (a) Collective intercalation (localization) of vermiculite clay, providing fresh of Cs+ in the selective layer spaces planar absorption sites for Cs+

Figure 3-18 Collective Structural Changes Induced by Cs+ Absorption to Vermiculite Clay

(a) Absorption of a cesium ion in an interlayer

(b) Absorption of new cesium ions in the adjacent site (c) Collective absorption of cesium ions

(e) Separation of the clay layers and appearance of new surface absorption

site (d) Shrinkage of the interlayer due to the absorption of may cesium ions

Clay sheet being separated

Absorption of cesium ions on the new surface appeared due to the separation Shrinkage layer

Figure 3-19 Absorption of Cesium One after Anotherｆ like “Domino Toppling” and Schematics of Structural Change of Vermiculite

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(Box7) Radioactive Cesium in Demersal Fish

Some may have concerns that “contaminated soil and feeding on contaminated organisms will increase and maintain radioactive cesium contamination in demersal fish”. However, as was explained in Part One, overall contamination levels are declining. Moreover, as the following discussion illustrates, it is thought that contamination will continue to fall with the passage of time. It is known that radioactive cesium that was released into the seawater by the accident tends not to contaminate fish if it becomes attached to clay. However, that portion that has not become attached (i.e., is absorbed by organisms) does become a source of contamination. According to a survey that was conducted in 2011 and 2012, 20 % of cesium in marine soil off the coast of Fukushima Prefecture has not be absorbed in clay and is thus in organic matters. It is presumed that these organic matters are a source of fish contamination. The results of monitoring conducted by Fukushima Prefecture show that radioactive cesium concentrations are steadily falling without exception even for olive flounder and other demersal fish species. However, this decreasing trend is taking considerably longer than the biological half-life for individual fish (approximately 100 days), as the cesium has an ecological half-life of between 200 and 300 days. Given this, it is thought that demersal fish are newly ingesting radioactive cesium; however, this newly ingested radioactive cesium is not raising concentrations in demersal fish, but rather only slowing the speed at which concentrations are decreasing. In other words, it is thought that the main contamination occurred immediately after the accident. Additionally, it is thought that the amount of radioactive cesium that is newly ingested into the bodies of bottom fish will fall steadily due to the dispersal and dilution of radioactive cesium concentrations in the seawater and continued absorption of radioactive cesium to clay in marine soil. As was mentioned in Chapter 6, it has been reported that cesium continues to be absorbed in clay in a manner resembling a domino effect. Thus, it is thought that the radioactive cesium in organic matters that inhabit marine soil is transferring to the clay with the passage of time and reaching a point where it will no longer have an impact on living beings. Moreover, for Pacific cod and olive flounder, which showed high concentrations of radioactive cesium in a relatively large area, the investigative research described in Chapter 1 reveals that the amount of radioactive material absorbed by fish since the 2011 year class is thought to be low and that amount of radioactive material absorbed by all year classes including prior to the accident since the winter of 2012 is low. Given these points, it is thought that radioactive cesium contamination in demersal fish will continue to decrease without any further increases.

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Part Four. Efforts to Address Unfounded Reputational Damages and Misinformation Present Domestically and Overseas Chapter 1. Domestic Situation Regarding Unfounded Reputational Damage and Misinformation

Part One of this report explained that concentrations of radioactive materials in fishery products, caused by the Fukushima Daiichi NPS accident, have largely declined; and that rigorous inspections and response measures for over-limit cases have ensured safety. However, the Fukushima Daiichi NPS accident has had a major psychological impact on consumers. Since 2013, the Consumer Affairs Agency has regularly conducted surveys of consumers analyzing unfounded reputational damages or misinformation. In the survey, consumers stating that they “hesitate to buy food products made in Fukushima because they wish to buy food that does not contain radioactive materials” amounted to 19.4 % (of all respondents) in February 2013, 17.9% in August 2013, 15.3 % in February 2014, 19.6 % in August 2014,17.4 % in February 2015, 17.2 % in August 2015, and 15.7 % in February 2016. [4]. To investigate the state of recovery from the Great East Japan Earthquake in the marine product processing industries of Aomori, Iwate, Miyagi, Fukushima, and Ibaraki Prefectures, the Fisheries Agency conducted the third questionnaire survey targeting 890 enterprises, including affiliated enterprises with the National Federation of Fishery Processor’s Co-operative Associations in those five disaster-affected prefectures, between November 12, 2015, and January 31, 2016. This survey followed previous two surveys that were conducted between February 28 and March 12, 2014 (the first survey targeting 3 affected-prefectures) and between November 17, 2014 and January 23, 2015(from these survey onward, targeting five disaster-affected prefectures). Responses were received from 30% of the targeted enterprises (268 enterprises). The survey revealed that 44% of respondents identified “unfounded reputational damages and misinformation and securing sales channels” as a major “problem in reconstruction efforts (previous result was 31%). This figure matched that shown in the previous survey and indicates that this matter remains to be a serious problem. In the survey of the Fisheries Agency, when asked about measures that will be required to improve sales channels, respondents said “sales outside of established sales channels,” “development of new products,” and “participation in exhibitions, etc.” among others. Thus, the recovery of sales channels remains delayed despite progress made in restoring production capacity. In particular, the development of sales channels outside of established channels and other such measures will continue to constitute important issues to be addressed [5, 6, 7].

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Chapter 2. Enhanced Provision/Dissemination of Information, Domestically and Internationally

In the aftermath of the Fukushima Daiichi NPS accident, consumer interest has risen in information on origin (harvest area) of fresh fishery products. In response, the Fisheries Agency has recommended clearer demarcation and labelling of harvest areas for fishery products harvested in the Pacific off the east coast of Japan. More specifically, it recommends labelling of harvest area using seven water areas for migratory fish species; and “Offshore Prefecture” for coastal fish species (i.e., fish species other than migratory fish) (Figure 4-1) [83]. The provision of information in a way that is both accurate and easy-to-understand is important to address misinformation resulting in unfounded reputational damages, both domestically and internationally. The Fisheries Agency is engaged in efforts to provide accurate and easy-to-understand information by publishing monitoring results on radioactive materials in fishery products; by publishing Q&As on the impact of radioactive materials on marine products, in both Japanese and English (Figure 4-2); and by holding briefing sessions for consumers, distributors, and domestic and international press (Figure 4-3). Further, in order to ensure thorough understanding of consumers, the Consumer Affairs Agency and other related government agencies have coordinated with local governments, consumer groups, and others to engage in “risk communication” on the topic of radioactive materials within foods, assembling experts, consumers, business operators, and administrators for a national dialogue and opinion-exchange in various parts of Japan.

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Examples of Labelling of harvest area

Figure 4-1 Labelling of Harvest Area in the Pacific off the East Coast of Japan [83]

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Figure 4-2 Publishing Inspection Results and Q&As on the Fisheries Agency Website

Figure 4-3 Briefing Sessions for Foreign Press, etc.

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Chapter 3. Response to International Issues

4-3-1 Response to Import Restrictions Imposed by Foreign Countries and Regions The Fukushima Daiichi NPS accident has also impacted foreign trade. After the accident, some countries and regions introduced measures to demand, for the import of fishery products from Japan, such as by requiring certificate of production place and/or pre-export testing of radionuclides. Some countries and regions also introduced measures to ban imports on fishery products from specific areas of Japan or coming under specific categories (Table 4-1). In order to deal with demands for such certificates, the Fisheries Agency has responded to these demands by issuing certificates and has also provided governments and media of other countries and regions with survey results and information on measures being taken in Japan to ensure the safety of fishery products. As the result of actively providing information to them, the safety of Japanese foodstuff has been recognized to a significant degree by countries and regions that imposed import restrictions in the past. Twenty countries, including India (February 2016), completely lifted import-restriction measures and Brunei (February 2015), the EU (January 2016), and other counties and regions eased restrictions as of the end of 2016. The Japanese standard limits for radioactive materials are established by the Ministry of Health, Labour and Welfare in consultation with experts from the Food Safety Commission and the Pharmaceutical Affairs and Food Sanitation Council etc., based on scientific foundations. Compared with international standards, they are proper and set appropriate limits. Monitoring of radioactive materials in foods is carried out in accordance with the Nuclear Emergency Response Headquarters’ Guidelines, and local governments take the lead in systematically focusing on those items and regions that show potential of exceeding limits, on highly-consumed items, on major products, etc., and food items distributed in the market are considered to have their safety guarantee. Therefore, the Fisheries Agency has pointed out that the ban of imports of all fishery products from accident-affected areas is not based on scientific evidences and unjustifiable. The WTO/SPS Agreement stipulates that measures taken by WTO members shall be based on scientific principles and a risk assessment, shall not arbitrarily or unjustifiably discriminate between members, and shall not be more trade-restrictive than necessary. Japan is working through diplomatic channels to repeal the lifting of such measures, and has also raised “specific trade concern” regarding those measures at the WTO/SPS Committeeo meetings. In particular, the Republic of Korea (Korea) has strengthened the trade-restrictive measures such as imposing an import ban on all fishery products from eight prefectures, including Fukushima Prefecture since September 2013. Following such actions, the Government of Japan provided information and explanation through bilateral consultations as well as at the WTO/SPS Committee meetings. Japan also agreed to have field surveys conducted by “the expert committees” established by Korea. Despite these efforts, Japan received no indication from Korea that these restrictive measures would be lifted. Japan o A Committee established for ensuring implementation of the SPS Agreement (one of the Agreements (Annexes) which constitute the WTO Agreement).

111 thus initiated in May 2015 the dispute settlement procedures under the WTO Agreement. Japan will continue pursuing the case under the dispute settlement procedures in accordance with WTO rules while at the same time calling for Korea to lift the trade-restrictive measures through bilateral consultations.

Table 4-1 Import Restrictions Imposed on Fishery Products from Japan as Imposed by Major Countries and Regions (as of March 31, 2016) 1) Import Bans on Fishery Products from Certain Regions The Republic of Korea Target Prefectures Nature of Regulation Aomori, Iwate, Miyagi, Fukushima, Ibaraki, Import ban Tochigi, Gunma, Chiba (8 prefectures) Hokkaido, Tokyo, Kanagawa, Aichi, Mie, Ehime, Demands government-issued test certificate of Kumamoto, Kagoshima (8 prefectures) radionuclides All other prefectures Demands government-issued certificate of production place  Standard limits: radioactive cesium 100 Bq/kg, radioactive iodine 300 Bq/kg  Additionally, if inspection within the Republic of Korea detects even a small amount of radioactive cesium or radioactive iodine, additional test certificate for radioactive strontium and p other radionuclides will be required.

China Target Prefectures Nature of Regulation Miyagi, Fukushima, Ibaraki, Tochigi, Gunma, Import ban Saitama, Chiba, Tokyo, Niigata, Nagano (10 prefectures) All other prefectures Demands government-issued test certificate of radionuclides and certificate of production place  Standard limits - radioactive cesium: 800 Bq/kg, radioactive iodine: 470 Bq/kg  Additionally, the CODEX guideline levels (radioactive cesium: 1,000 Bq/kg, radioactive iodine: 100 Bq/kg) shall not be exceeded.

p Additional radionuclides required by the Republic of Korea: Pu-238, Pu-239, Pu-240, Am-241, Sr-90, Ru-106, I-129, U-235, S-35, Co-60,Sr-89,Ru-103, Ce-144, Ir-192, H-3, C-14, Tc-99

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Russia Russian regulations on imports from Japan include regulations on food items in general, and additional individual regulations on fishery products and processed fishery products.

■Regulations on all food items Target Prefectures Nature of Regulation Fukushima, Ibaraki, Tochigi, Demands government-issued test certificate of Gunma, Chiba, Tokyo (6 prefectures) testing of radionuclides

All other prefectures Sampling Inspection in Russia

 Standard limits - cesium-137: 130 Bq/kg (fish and fishery products), 260 Bq/kg (dried fish)

■Fishery products and processed fishery products Facilities* Nature of Regulation Facilities situated in Iwate, Miyagi, Yamagata, Import ban Fukushima, Ibaraki, Chiba, Niigata (7 prefectures) Demands government-issued test certificate of Facilities situated in Aomori radionuclides Facilities in all other prefectures Sampling Inspection in Russia * For fishery products or processed fishery products to be exported to Russia, the facilities in which the products undergo final processing or are stored for export to Russia shall be registered to Russia.

Brunei Target Prefectures Nature of Regulation Fukushima (except seaweeds) Import ban

Demands government-issued test certificate of Fukushima (seaweeds) radionuclides Demands government-issued certificate of All other prefectures production place  Standard limits - radioactive cesium: 1,000 Bq/kg

Taiwan Target Prefectures Nature of Regulation Fukushima, Ibaraki, Tochigi, Gunma, Chiba (5 Import ban prefectures) Iwate, Miyagi, Tokyo, Ehime (4 prefectures) Demands testing report of radionuclides Other than the 9 aforementioned prefectures Demands certificate of production place  Standard limits - radioactive cesium:100 Bq/kg, radioactive iodine:300 Bq/kg

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Singapore Target Prefectures Nature of Regulation Fukushima Import ban Demands government-issued test certificate of Ibaraki, Tochigi, Gunma (3 prefectures) radionuclides Demands certificate of production place, All other prefectures issued by the government or Chamber of Commerce and Industry  Although 1,000 Bq/kg for radioactive cesium and 100 Bq/kg for radioactive iodine are employed as standard limits for food, in the case of importation, no imports will be permitted if even a small amount of radionuclides is detected.

Macao Target Prefectures Nature of Regulation Fukushima Import ban Miyagi, Tochigi, Ibaraki, Gunma, Saitama, Tokyo, Demands testing report of radionuclides with Chiba, Nagano, Niigata, Yamagata, Yamanashi (11 information of production place issued by prefectures) designated inspection organization(s)  Standard limits - radioactive cesium: 1,000 Bq/kg, radioactive iodine:100 Bq/kg

New Caledonia Miyagi, Yamagata, Fukushima, Ibaraki, Tochigi, Gunma, Saitama, Chiba, Tokyo, Niigata, Import ban Yamanashi, Nagano (12 prefectures) Demands government-issued certificate of Other than the 12 aforementioned prefectures production place

2) Demands test Certificate of Radionuclides or Certificate of Origin Indonesia Target Prefectures Nature of Regulation Demands government-issued test certificate of All 47 prefectures radionuclides

French Polynesia Target Prefectures Nature of Regulation Miyagi, Fukushima, Ibaraki, Tochigi, Gunma, Demands government-issued test certificate of Saitama, Chiba, Tokyo, Kanagawa, Yamanashi, radionuclides Nagano, Shizuoka (12 prefectures) Demands government-issued certificate of All other prefectures Production place  Standard limits - radioactive cesium: 1,250 Bq/kg, radioactive iodine: 2,000 Bq/kg 114

United Arab Emirates Target Prefectures Nature of Regulation Aomori, Iwate, Miyagi, Fukushima, Ibaraki, Tochigi, Gunma, Saitama, Chiba, Tokyo, Kanagawa, Demands government-issued test certificate of Niigata, Yamanashi, Nagano, Shizuoka (15 radionuclides prefectures) Demands government-issued certificate of All other prefectures Production place  Standard limits - radioactive cesium: 1,000 Bq/kg, radioactive iodine: 100 Bq/kg

Egypt Target Prefectures Nature of Regulation Iwate, Miyagi, Fukushima, Ibaraki, Tochigi, Gunma, Demands government-issued test certificate of Chiba (7 prefectures) radionuclides Demands government-issued certificate of Other than the 7 aforementioned prefectures Production place  Standard limits - radioactive cesium: 100 Bq/kg (foods including fishery products), 40 Bq/kg (feeds)

Morocco Target Prefectures Nature of Regulation Miyagi, Yamagata, Fukushima, Ibaraki, Tochigi, Demands government-issued test certificate of Gunma, Saitama, Chiba, Tokyo, Kanagawa, Niigata, radionuclides Yamanashi, Nagano (13 prefectures) Demands government-issued certificate of All other prefectures Production place  Standard limits - radioactive cesium: 500 Bq/kg, radioactive iodine: 2,000 Bq/kg

EU Target Prefectures Nature of Regulation Fukushima, Iwate, Miyagi, Ibaraki, Tochigi, Gunma, Demands government-issued test certificate of Chiba (7 prefectures) (Excluding seaweed, live fish, and scallops) radionuclides (Seaweed, live fish, and scallops) Sampling test by the EU Demands government-issued certificate of All other prefectures Production place ● Standard limits - radioactive cesium: 100 Bq/kg for food from Japan (radioactive cesium: 1,250 Bq/kg, radioactive iodine: 2,000 Bq/kg in EU)

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3) Demands Certificates for Some Regions Hong Kong Target Prefectures Nature of Regulation Fukushima, Ibaraki, Tochigi, Gunma, Chiba (5 Demands government-issued test certificate of prefecture) radionuclides All other prefectures Sampling in Hong Kong  Standard limits - radioactive cesium: 1,000 Bq/kg, radioactive iodine: 100 Bq/kg

Brazil Target Prefectures Nature of Regulation Demands government-issued test certificate of Fukushima radionuclides  Standard limits - radioactive cesium: 1,000 Bq/kg, radioactive iodine: 100 Bq/kg

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4-3-2 Response to the Certificates Demanded by Other Countries and Regions In the wake of the accident at the Fukushima Daiichi NPS, some countries and regions are demanding that imports of fishery products from Japan be accompanied by a certificate of production place and/or test certificate of radionuclides (Table 4-1). The Fisheries Agency and some prefectural governments (hereafter, the “certifying organizations”) issue such certificates, based on notifications from the Director-General of the Fisheries Agency, to the Republic of Korea, China, Hong Kong, the EU, Thailand, Singapore, Egypt, and others after confirming the production areas of products to be exported and that the results of radioactive materials tests meet the limits those countries demand. In FY2014, some 14,000 certificates were issued over the course of the year. Although certificates for exports are required every day, the issuance of those certificates often takes several days. This presents a serious issue particularly for exports of fishery products that demand freshness. Given this, the Government of Japan hopes to see import restrictions relaxed and lifted as soon as possible.

(1) The Process up to Issuance of Certificates After receiving an application for a certificate from a business, a certifying organization inspects the business’s application documents. The points that the certifying organization looks at are, 1) general outline of the export (i.e., exporter, importer, port of loading, date of export, etc.), 2) area of production of the exporting product), and 3) results of radioactive materials test and sampling (extraction of samples from lots of exported foods to provide for radioactive materials tests). In order to examine these items, the certifying organization demands documents that confirm the general details of the export (e.g., invoice, etc.), documents that show proof of the area of production that the producer of the exported product (e.g., fishery cooperative, etc.) prepared and issued to the business after confirming fishing areas and sales records, an inspection report on the radioactive materials test that was issued by an assessment body, and documents reporting the sampling methods that were prepared by the business. If the certifying organization finds any deficiencies or points requiring clarification in the application documents, it verifies the facts of the matter by demanding that the applicant provide additional materials or making direct inquiries to the producer, assessment body, etc. The certifying organization only prepares a certificate and issues it to the business if, based on the above-mentioned inspection, it confirms that the product to be exported meets the conditions demanded by the export partner.

(2) The Radionuclides Test Required for a Certificate In principle, the radioactive materials test required for the issuance of a certificate is conducted by a “registered conformity assessment body” stipulated in the Food Sanitation Act.q Assessment bodies ensure the reliability of their test results by conducting test analyses based on a notification “on methods q A “registered conformity assessment body” is a testing organization permitted to conduct product tests as an organization acting for the government after being registered by the Minister of Health, Labour and Welfare based on Article 33 of the Food Sanitation Act. Requirements for registration include possession of stipulated machines, implements, and other facilities; the execution of tests by persons possessing the requisite knowledge and experience; and independence from businesses being tested

117 for testing for radioactive materials in food products” (March 15, 2012) that the Ministry of Health, Labour and Welfare issued to local governments (Figure 4-4). As for sampling for radioactive materials tests, in principle, applying businesses are instructed to ask an assessment body to handle sampling. If sampling by the assessment body is difficult, sampling can be conducted by the business in the presence of a third party (e.g., employee of the prefectural government, municipality, fishery cooperative or fish market, etc.) or by the business based on standards established by the Fisheries Agency (Table 4-2). Regarding the radionuclides to be tested and detection limits, applying businesses are instructed to conduct measurements corresponding to the demands of those countries and regions that have import restrictions in place. For example, the EU requires measurements of cesium-134 and cesium-137 that do not exceed 100 Bq/kg, while the Republic of Korea, requires measurements of iodine, cesium-134, and cesium-137 that do not exceed 0.7 Bq/kg.

Table 4-2 Sampling Standards No. of packages in 1 lot No. of opened packages (n) N ≦ 2 1 3 ≦ N ≦ 150 3 150 ＜ N ≦ 1,200 5 1,200 ＜ N 8

Figure 4-4 Inspection for Radioactive Cesium with Gamma Ray Spectrometry

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4-3-3 Examples of Radioactive Materials Detected in Fishery Products after Exportation from Japan

As was mentioned in 4-3-1 and 4-3-2, various countries and regions have implemented import regulations and measures following the nuclear accident. They are demanding certificates, banning imports, and strengthening their inspections for radioactive materials when products are imported. Japan exported fishery products to the world as follows: 424,000 tons in 2011, 440,000 tons in 2012, 552,000 tons in 2013, 471,000 tons in 2014, and 556,000 tons in 2015. As is shown in Table 4-3, although there have been cases where miniscule levels of radionuclides were detected in import inspections, none have exceeded the limits of either importing countries or Japan. Some countries have relaxed their import regulations in light of this. These developments provide evidence that Japan’s monitoring and other initiatives to ensure the safety of its fishery products, export inspections, and verifications for the issuance of certificates are being properly executed.

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Table 4-3 Results of Import Inspections by Foreign Countries and Regions for Japanese Food and Fishery Products United States Period Until March 10, 2014 No. of 225 (fishery products) (inspections targeted imported items and US domestic items) inspections Detections None Website http://www.fda.gov/NewsEvents/PublicHealthFocus/ucm247403.htm

Hong Kong Period Until March 31, 2016 No. of 49,561 (fishery products) inspections Detections None Website http://www.cfs.gov.hk/english/programme/programme_rafs/programme_rafs_fc_01_3 0_Nuclear_Event_and_Food_Safety.html

Australia Period Until December 2014 No. of More than 1,400 (including non-fishery products) inspections Detections All inspections met Australian limits Website http://www.agriculture.gov.au/import/food/notices/2014/ifn01

Singapore Period Until June 2014 No. of More than 18,000 (including non-fishery products) inspections Radionuclides were detected in 0.14% of all inspections. (No cases of fishery Detections products’ exceeding Singaporean limits were reported by the Singaporean government, etc.) Absolutely no cases were detected from January 2013. Website http://www.ava.gov.sg/docs/default-source/publication/ava-vision/ava_newsletter-lr

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Taiwan Period Until March 7, 2016 No. of 30,019 (fishery products) inspections Detections 2011: 29; 2012: 0; 2013: 1 2014: 1; 2015: 1 (Cs: 6 Bq/kg) Website http://www.fda.gov.tw/TC/siteList.aspx?sid=2356

Canada Period (1) April to June 2011 (2) September to October 2012 No. of (1) 44 (fishery products) (2) 30 (fishery products) inspections Detections (1) 1 (Cs: 7.66 Bq/kg) (2) None Website http://www.inspection.gc.ca/food/imports/japan-nuclear-crisis/eng/1384447285082/1 384448940388

The Republic of Korea (Fishery products) Detection of trace Detection of trace No detection amounts (customs amounts (customs

Year cleared) rejected)*1 Number of Weight Number of Weight Number of Weight inspections (tons) inspections (tons) inspections (tons) 2012 4,729 20,526 101 2,704 －－ 2013 5,328 20,543 9 160 1 0 2014 5,290 18,265 －－ 4 20 2015 6,525 22,523 －－－－

Total 21,872 81,857 110 2,864 5 20 *1: 2013: detection of 1 Bq/kg; 2014: detection of 1 Bq/kg, 1 Bq/kg, 3 Bq/kg, 2 Bq/kg URL： http://www.mfds.go.kr/index.do?mid=1077

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4-3-4 IAEA Evaluation of Food Monitoring The International Atomic Energy Agency (IAEA), at the request of the Government of Japan, organized two review missions in 2013 (April and November/December) and one review mission in 2015(February) [85; 86] to review efforts being made along the “Mid-and-Long-Term Roadmap towards the Decommissioning of TEPCO's Fukushima Daiichi Nuclear Power Station Units 1-4” [84]. The final report of the third review mission was publicly issued in May 2015. With respect to the monitoring of food, the team stated in the 2nd Review Report that introduction of limits for food controls, the comprehensive monitoring system for seawater and distributed food products, and measures such as the distribution restrictions ensure the safety of the marine fishery products in the market (Figure 4-5) [86]. Additionally, the IAEA makes evaluations of the comprehensive information report relating to the Fukushima Daiichi NPS issued by the Government of Japan, which were first posted to the IAEA website in December 2013. IAEA states with respect to the safety of food: “systems are in place and are being implemented that prevent food and agricultural products with levels of cesium radionuclides in excess of the national regulatory limits from entering the food supply chain” and “the Joint IAEA / FAO Division understands that the measures taken to monitor and respond to issues regarding radionuclide contamination of food are appropriate, and that the food supply chain is under control” (February 27, 2015) [53]. Furthermore, IAEA noted with regard to proficiency test (whereby the IAEA confirms performance of laboratories through a process in which participating laboratories analyze seawater samples provided by the IAEA for concentrations of tritium, cesium-134, cesium-137, and strontium-90 and then reports analytical results to the IAEA) that the results of these tests “have shown a high level of accuracy of the data reported by Japanese laboratories” [52, 53, 54]

Figure 4-5 Review by the IAEA [86]

In addition to the above, interlaboratory comparisons of radioactive materials in fishery products, seawater, and marine soil have been carried out by and between the IAEA and Japanese analysis laboratories (whereby samples obtained jointly by both Japanese laboratories and the IAEA are analyzed respectively and the results thereof are then compared (ILC: interlaboratory comparison)). The IAEA

122 concluded, with respect to the ILC of seawater and marine soil: “The results we have obtained to date are very good and should increase confidence that the data regularly reported by Japan presents an accurate picture of the levels of radioactivity in the near-shore coastal waters east of Japan,” and “IAEA-run comparison studies in 2014 and 2015, using seawater and sediment samples collected near Fukushima Daiichi, also indicated that the participating Japanese laboratories’ results were reliable. ” With respect to the ILC of fishery products, the IAEA concluded: “The comparison study found no statistical differences between the results reported by the three laboratories and the IAEA’s laboratory, located in Monaco, indicating that they have the capacity to analyze fish accurately.” (Figure 4-6) [53, 54, 87].

Excerpt from an IAEA press

・ Three Japanese laboratories that took part in an IAEA study produced reliable data on the level of radioactive caesium in fish caught near the Fukushima Daiichi accident site, the IAEA’s Environment Laboratories announced today. ・ The comparison study found no statistical differences between the results reported by the three laboratories and the IAEA’s laboratory, located in Monaco, indicating that they have the capacity to analyze fish accurately. ・ The participating laboratories all found very small amounts of caesium in the fish. The levels measured were below 5 Bequerel per kilogram, which is far below the Japanese regulatory limit for human consumption of general foods, which is 100 Becquerel per kilogram.

Source

An IAEA expert at the Onahama fish market confirmed fishery samples (Iwaki City, Fukushima Prefecture)

Figure 4-6 Interlaboratory Comparisons of the Radioactivity of Fishery Products Taken by the IAEA and Japanese Analysis Laboratories [87]

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Conclusion

This report has comprehensively assessed the results of the monitoring of fishery products for radionuclides, which has been carried out since the Fukushima Daiichi NPS accident in 2011, and presented the results of a broad range of research concerning radionuclides. The results of monitoring indicate that in the immediate post-accident period, a considerable number of fish species, mainly in waters off Fukushima Prefecture, were found to contain radionuclides at concentrations in excess of 100Bq/kg. However, concentrations declined with the passage of time, such that no sample in excess of 100 Bq/kg have recently been found approximately five years later. Further, although some cases of leakage of contaminated water have been reported since the accident, no influence on seawater and fishery products has been observed outside the Fukushima Daiichi NPS port. Preventive and multilayered initiatives are being pursued, as can be seen in the start of the operation of a sub-drain, the completion of seaward-facing impermeable walls, and the completion of the freezing of a frozen ground wall. According to monitoring results, concentrations of radioactive cesium in fishery products are clearly falling, and almost no effects from radioactive strontium are being seen. Based on these results and investigative research, it is thought that contamination of fishery products by radioactive materials was caused by contaminated water containing extremely high concentrations immediately following the accident. The role in the contamination of fishery products of slight variations in comparatively low-level contaminated water caused by leakages of contaminated water from the nuclear power station, which has become a matter of recent concern, is thought to be small. That said, despite the fact that today, five years since the accident, almost no marine fish species exceed the limits, restrictions on shipping and distribution continue to be placed on some regions and fish species. These measures are being implemented appropriately by local governments and others. However, the efforts being made by national and local governments as well as fishermen to ensure the safety of fishery products are not necessarily well understood, and the persistence of misinformation and resulting unfounded reputational damages, both domestically and internationally, continues to be a problem. Indeed, although some countries and regions have relaxed or lifted the import regulations they placed on Japanese products after the accident, some countries and regions continue to maintain them. This presents a concern to fishery operators and processors who are struggling to recover from the accident and rebuild their production systems. In order to continue to secure the safety of marine products and the trust of consumers, it is necessary, as a matter of obligation, for the national government to work for the delivery of safe fishery products to the market by continuing its monitoring of fishery products. Further, the national government must endeavor to shed light on contamination mechanisms so that it can present factors behind the appearance of contaminated fish as well as predictions concerning reductions of such fish to fishery operators and consumers. As of the end of March 2016, more than 88,000 results have been collected from inspections of radioactive materials in fishery products. Japan is committed to utilizing this vast supply of results to

124 conduct verifications and to provide proper information on the safety of fishery products for domestic and international use. Japan also works toward getting import regulations relaxed or lifted in importing countries by taking appropriate steps to address their concerns and doubts. Moreover, Japan is committed to enhance the faith and trust in its efforts to guarantee the safety of its fishery products by sharing information and cooperating with international organizations and relevant countries/regions and by welcoming further verifications.

This report was prepared with the cooperation of the following persons: Dr. Tomoo Watanabe, the headquarters of the Japan Fisheries Research and Education Agency(FRA) ; Dr. Takami Morita, the Leader of the Radioecology Group, Dr. Hideki Kaeriyama, Dr. Yuya Shigenobu and Dr. Shizuho Miki, the Radioecology Group, Research Center of Fisheries Oceanography and Marine Ecosystem, National Research Institute of Fisheries Science, Japan Fisheries Research and Education Agency; Dr. Yutaka Kurita, the Leader of the Coastal Resources Group, Fisheries Oceanography and Resource Department, Tohoku National Fisheries Research Institute, Japan Fisheries Research and Education Agency; and Dr. Yoji Narimatsu, the Demersal Fishes Research Group, Tohoku National Fisheries Research Institute, Japan Fisheries Research and Education Agency.

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82. Shimane H. (1969). Vermiculite and allied minerals. Ed. The clays of Japan organizing committee. The clay of Japan.Geological survey of Japan. pp.140 - 142. 83. Fisheries Agency. (2011). The way of displaying the production area of a raw fisheries product mainly caught at the Pacific of Eastern part of Japan. (in Japanese). (http://www.jfa.maff.go.jp/j/press/kakou/111005.html). 84. Agency for Natural Resources and Energy. (2013). Announcement of the Revised Version of the Mid-and-Long-Term Roadmap towards the Decommissioning of TEPCO's Fukushima Daiichi Nuclear Power Station Units 1-4. (http://warp.da.ndl.go.jp/info:ndljp/pid/10217941/www.meti.go.jp/english/press/2013/0627_01.html) . 85. IAEA. (2013). IAEA MISSION REPORT, IAEA INTERNATIONAL PEER REVIEW MISSION ONMID-AND-LONG-TERM ROADMAP TOWARDS THE DECOMMISSIONING OF TEPCO’S FUKUSHIMA DAIICHI NUCLEAR POWER STATION UNITS 1-4. (https://www.iaea.org/sites/default/files/missionreport041213.pdf). 86. IAEA. (2014). IAEA MISSION REPORT, IAEA INTERNATIONAL PEER REVIEW MISSION ON MID-AND-LONG-TERM ROADMAP TOWARDS THE DECOMMISSIONING OF TEPCO’S FUKUSHIMA DAIICHI NUCLEAR POWER STATION UNITS 1-4, SECOND MISSION. (http://www.iaea.org/sites/default/files/IAEAfinal_report120214.pdf). 87. IAEA. (2016). IAEA finds Japanese labs reliable in analyzing fish from sea near Fukushima. (https://www.iaea.org/newscenter/pressreleases/iaea-finds-japanese-labs-reliable-in-analysing-fish-fr om-sea-near-fukushima). 88. Chiba Prefecture. (2015). Summary of the plan for inspection of radioactive materials in agricultural, livestock and fisheries products in Chiba prefecture. (in Japanese). (http://warp.da.ndl.go.jp/info:ndljp/pid/10338413/www.mhlw.go.jp/file/04-Houdouhappyou-1113500 0-Shokuhinanzenbu-Kanshianzenka/0000140058.pdf).

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Appendix Radioactive Material Analysis Flowcharts

Box 5 mentions methods for measuring radioactive strontium and plutonium data that are provided by the Fisheries Agency and Japan Fisheries Research and Education Agency. As the box notes, measurement of these elements requires complex procedures. However, it is thought that information on the actual measurement methods used will be required in certain cases, particularly when comparing the data presented here (Table 4) with pre-accident data and data of other countries and conducting evaluations. The following flowcharts (used in measuring the data presented in Table 4) are presented here for this purpose.

1. Sample preparation 2. Measurement of radioactive strontium 3. Measurement of plutonium

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1. Sample preparation

weight measurement (wet) ↓ drying process (hot air drying machine) ↓ weight measurement (dried) ↓ carbonization process (electric furnace) ↓ 280 ºC 4 hours ↓ 320 ºC 4 hours cool to room temperature ↓ ↓ 340 ºC 4 hours ↓ 360 ºC 4 hours cool to room temperature ↓ ↓ 380 ºC 4 hours ↓ 400 ºC 2 hours ↓ 420 ºC 4 hours cool to room temperature ↓ ashing process (electric furnace) ↓ 450 ºC 24 hours ↓ 500 ºC 24 hours ↓

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2. Measurement of radioactive Strontium ash sample (equivalent to 1kg of wet sample) ← Sr 50.0mg ←aqua regia thermolysis

← HNO3 thermolysis

← HNO3 heating for dissolution

filtering (No.5C)

H20 wash

filtrate residue

← H2Odisposed ← NaOH pH 10 or higher

← Na2CO3 10-30g heating and wait for formig precipitation still standing decantation・centrifugation

precipitation supernatant ← HCl dissolution can be used for analysis of Cs-137

← H2O heating

← H2C2O4 10～30g

← NH4OH pH 4.0～4.2

heating and wait for formig precipitation still standing filtering (No.5C)

(NH4)2C2O4(0.2w/v%) wash

precipitation filtrate disposed heating 600ºC 3h ← HCl (1+3) evaporation to dryness ← HCl (1+23) 200ml filtering (No.5C) HCl (1+23) wash ← HCl (1+23) filtrate (500ml) residue disposed go to next page

135

Dowex 50W-X8, 100～200 mesh, 3cm φ×26cm speed of flow 4～6cm/min disposed ← ion exchange ←H2O 30ml disposed ← resin

column ←CH3COONH4 (15.4w/v%) - methanol (1:1) 1100ml disposed ←

←CH3COONH4 (15.4w/v%) 600ml

evaporation to dryness

←H2O 10ml

←HNO3 10ml evaporation to dryness ←Ba 20mg

←CH3COONH4 (46w/v %) 2ml

←NH4OH (1+1)

←CH3COOH (7+13) pH5.0~5.5

heating

←K2CrO4 (30w/v %) 1ml heating and wait precipitation foming still standing

filtrate (No.5C)

←CH3COONH4 (0.6w/v %) wash

filtrate precipitation ←NaOH 4g disposed

←(NH4)2CO3 40g heating and wait precipitation foming

filtrate (25G4) ←(NH4)2CO3 (1w/v %) wash

precipitation filtrate

←HNO3 (1+1) disposed

←H2O wash

←H2O 20ml ←Fe 5mg

←NH4Cl 1g ←phenolphthalein solution 0.5ml heating

←NH4OH heating and wait for formig precipitation

filtering (No.5A) (record the date and time of scavenging)

warm NH4OH（1+500) wash

filtrate precipitation

←(NH4)2CO3 (saturated) 5ml disposed heating and wait for formig precipitation still standing filtering (1G4)

NH4OH（1+100) wash

precipitation filtrate ethanol wash disposed drying 110 ºC、1h cooling at room temperature calculation of recovery rate by ICP-AES measurment

leave for 2 weeks or longer

go to next page

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← HCl (1+1)

← H2O ←Fe 5.0mg, Y 50ug ←phenolphthalein solution 0.5ml heating

←NH4OH heating and wait for formig precipitation

filtering (No.5A) (record the date and time of scavenging)

warm NH4OH（1+500) wash

precipitation filtrate ← warm HCl (1+5) ← HCl

←warm H2O 40ml wash stock

←NH4Cl 1g ←phenolphthalein solution 0.5ml heating

←NH4OH heating and wait for formig precipitation

filtering (No.5A)

warm NH4OH（1+500) wash

precipitation filtrate ← warm HCl (1+5)

←warm H2O 40ml wash disposed

←NH4Cl 1g ←phenolphthalein solution 0.5ml heating

←NH4OH heating and wait for formig precipitation

filtering (No.5A)

NH4OH（1+100) wash

precipitation filtrate dry (infrared lamp) 90Y-beta ray measurement disposed

137

3. Measurement of Plutonium ash sample ← add standard solution for 242Pu or 236Pu ← add standard solution for 243Am or 244Cm

← HNO3 50ml evaporation to dryness

← H2O2 10ml heating repeat till dried residue to white

← HNO3 evaporation to dryness

← HNO3 (3+2) 100ml heating filtering (GA-100)

(NH4)2C2O4(0.2w/v%) wash

filtrate (Pu, Am) residue

←HNO3 (3+2) 120ml ion exchange Am analysis ←HCl (5+1) 300ml resin column ←NH4I 50ml + HCl 30ml mix

evaporation to dryness

←HNO3 5ml

←HClO4 1ml

evaporation to dryness

Pu sample for electrodeposition

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Sample for Am analysis evaporation to dryness

←HNO3 (3+2) 50ml

←H2O 250ml ←Ca carrier solution 5ml

←H2C2O4 10g

←(NH4)2C2O4 10g heating

← NH4OH (pH=1.5) filtering (5C)

residue filtrate

ashing (550 ºC 2h) ←HCl ←Fe carrier solution 1ml

←NH4Cl 10g

← NH4OH heating

filtering (5C)

residue filtrate ←HCl (7+3) 20ml evaporation to dryness ←HCl (6+1) 20ml

Dowex 1-X8, 100～200 mesh

ion exchange ←HCl (6+1) 50ml resin column

evaporation to dryness

←HNO3 (3+2) 20ml

←H2O2 a few drops heating for dissolution sample for electrodeposition

Dowex 1-X8, 100～200 mesh

ion exchange ←HNO3 (3+ 2) 30ml resin column

evaporation to dryness

←HNO3 5ml

←H2O2 a few drops evaporation to dryness sample for electrodeposition

139

sample for electrodeposition

←HNO3 1ml

←H2O2 a few drops

←CH3OH 12.6ml

Dowex 1-X4, 100～200 mesh

←HNO3 + CH3OH mix 20ml ion exchange ←NH SCN + CH OH mix 60ml resin 4 3 column ←HNO3 + CH3OH mix 50ml

←HCl + CH3OH mix 50ml

evaporation to dryness

←HNO3 5ml

←H2O2 1ml evaporation to dryness

←HClO4 1ml evaporation to dryness

sample for electrodeposition

←H2SO4 (1 + 9) 5ml

←NH4OH

←H2SO4 (1 + 9) electrodeposition 1.0 A 2~3h electrodeposition residue electrodeposition plate (alfa-spectrometry）

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Appendix Table Inspection Results for Radioactive Cesium Concentrations in Fishery Products (March 2011 – March 2016)

The preceding report explains the results of inspections on major fish species. However, there are additional monitoring activities on many additional fish species undertaken by coordinated efforts among national governments, prefectural governments, and relevant organizations. The results for each of these monitoring efforts are published on the Fisheries Agency website: (http://www.jfa.maff.go.jp/j/housyanou/kekka.html)

The appendix table contains data on the following items, separated into “Fukushima Prefecture” and “other prefecture” categories, and organized by fiscal year and by fish species. - Number of samples tested - Number and proportion of readings below the detection limit, and the value of detection limit (Note: detection limit for FY2011 has not been made available.) - Number and proportion of readings below 100 Bq/kg (A provisional regulation limit of 500 Bq/kg was used through FY 2011, but for the sake of comparison, the present table uses the standard limit of 100 Bq/kg) - Maximum value (Bq/kg) - Median value (Bq/kg) - Mean value (Bq/kg)

The median and mean values were calculated according to GEMS/Food* methods, as below:

Median: Calculated only if the number of readings below the detection limit constituted fewer than 50 % of the total. If such readings constituted 50 % or more of the total, the median was marked as “-”.

Mean: If readings below the detection limit constituted over 60% of the total number of readings, the mean was calculated according to (1) and (2) below. If the proportion of readings below the detection limit was 60% or less, the mean was calculated according to (3). (1) Set all below-detection-limit readings to 0 and calculate the mean. (2) Set all below-detection-limit readings to the value of the limit and calculate the mean. (3) Set all below-detection-limit readings to 1/2 the value of the limit and calculate the mean.

It is important to remember that, as stated in the preceding report, inspections are as a general rule performed prior to shipping and distribution. Also, it must be noted that monitoring results include those of items currently under shipping and distribution restrictions and not in active circulation in the market. Therefore, a reading in excess of the standard limit, does not mean that excessive levels of radioactive cesium were found in fishery products actively in circulation.

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※ GEMS/Food Abbreviation of the World Health Organization’s (WHO) Global Environmental Monitoring System/Food Contamination Monitoring and Assessment Programme. It collects data on chemical contamination in foods, and provides it to governments and Codex Alimentarius Committee etc. (http://www.who.int/foodsafety/chem/instructions_GEMSFood_january_2012.pdf?ua=1).

142

1.Inspection Results for Fishery Products in Fukushima Prefecture(Mar.2011-Mar.2016)

Number < Limit of Detection ≦100 Bq/kg Maximum Median Mean(1) Mean(2) Mean(3) Fiscal Item of LOD year Number (%) Number (%) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) samples (Bq/kg) ごく表層 very surface 1 イシカワシラウオ Ishikawa icefish (Salangichthys ishikawae) ～2011 26 2 8% - 26 100% 94 33 - - 35 2012 74 60 81% 11-20 74 100% 34 - 2.6 16 - 2013 97 86 89% 12-20 97 100% 19 - 1.1 15 - 2014 78 78 100% 12-20 78 100% <20 - 0 16 - 2015 67 67 100% 13-19 67 100% <19 - 0 16 - 2 コウナゴ Japanese sandlance (Ammodytes personatus) ～2011 21 8 38% - 9 43% 14,000 320 - - 1800 2012 62 55 89% 12-20 62 100% 10 - 0.94 15 - 2013 69 69 100% 12-20 69 100% <20 - 0 15 - 2014 72 72 100% 12-20 72 100% <20 - 0 16 - 2015 114 114 100% 12-20 114 100% <20 - 0 16 - 3 シラウオ Japanese icefish (Salangichthys microdon) ～2011 3 1 33% - 3 100% 67 12 - - 29 2012 1 1 100% 16 1 100% <16 - 0 16 - 2015 2 2 100% 14-17 2 100% <17 - 0 16 - 4 シラス Whitebait ～2011 59 15 25% - 46 78% 850 30 - - 100 2012 118 116 98% 9.5-20 118 100% 7.9 - 0.13 16 - 2013 199 199 100% 13-20 199 100% <20 - 0 16 - 2014 132 132 100% 11-20 132 100% <20 - 0 16 - 2015 108 108 100% 13-20 108 100% <20 - 0 16 - 5 ノレソレ Conger eel (Juvenile) (Conger myriaster) ～2011 1 1 100% - 1 100%

143 1.Inspection Results for Fishery Products in Fukushima Prefecture(Mar.2011-Mar.2016)

Number < Limit of Detection ≦100 Bq/kg Maximum Median Mean(1) Mean(2) Mean(3) Fiscal Item of LOD year Number (%) Number (%) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) samples (Bq/kg) 表層 Surface layer 6 アカカマス Red barracuda (Sphyraena pinguis) ～2011 1 0 0% - 1 100% 50 50 - - 50 2013 1 1 100% 15 1 100% <15 - 0 15 - 2014 2 2 100% 16 2 100% <16 - 0 16 - 2015 6 6 100% 14-20 6 100% <20 - 0 16 - 7 ウルメイワシ Round herring (Etrumeus teres) ～2011 1 0 0% - 1 100% 23 23 - - 23 2012 2 2 100% 15-16 2 100% <16 - 0 16 - 2013 5 5 100% 14-17 5 100% <17 - 0 15 - 2015 12 12 100% 13-18 12 100% <18 - 0 15 - 8 カタクチイワシ Anchovy (Engraulis japonicus) ～2011 12 1 8% - 11 92% 140 28 - - 39 2012 19 19 100% 12-20 19 100% <20 - 0 16 - 2013 33 33 100% 14-18 33 100% <18 - 0 16 - 2014 21 20 95% 13-20 21 100% 9.4 - 0.45 15 - 2015 31 30 97% 13-20 31 100% 11 - 0.35 16 - 9 カツオ Skipjack tuna (Katsuwonus pelamis) ～2011 1 1 100% - 1 100%

144 1.Inspection Results for Fishery Products in Fukushima Prefecture(Mar.2011-Mar.2016)

Number < Limit of Detection ≦100 Bq/kg Maximum Median Mean(1) Mean(2) Mean(3) Fiscal Item of LOD year Number (%) Number (%) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) samples (Bq/kg) 中層 Intermediate layer 15 カンパチ Greater amberjack (Seriola dumerili) ～2011 5 1 20% - 5 100% 73 22 - - 28 2012 1 1 100% 14 1 100% <14 - 0 14 - 2013 3 3 100% 14-17 3 100% <17 - 0 16 - 2014 1 1 100% 16 1 100% <16 - 0 16 - 16 ギンザケ Coho salmon (Oncorhynchus kisutsh) ～2011 1 0 0% - 1 100% 73 73 - - 73 17 クロマグロ Bluefin tuna (Thunnus thynnus) ～2011 5 0 0% - 5 100% 41 28 - - 30 2012 1 1 100% 16 1 100% <16 - 0 16 - 18 コノシロ Dotted gizzard shad (Konosirus punctatus) 2012 2 2 100% 13-16 2 100% <16 - 0 15 - 2013 1 1 100% 17 1 100% <17 - 0 17 - 2014 3 3 100% 13-15 3 100% <15 - 0 14 - 19 ゴマサバ Southern mackerel (Scomber australasicus) ～2011 9 2 22% - 9 100% 68 41 - - 36 2012 22 22 100% 13-19 22 100% <19 - 0 16 - 2013 53 52 98% 13-20 53 100% 6.4 - 0.12 15 - 2014 55 55 100% 13-20 55 100% <20 - 0 16 - 2015 64 64 100% 13-19 64 100% <19 - 0 16 - 20 サクラマス Cherry salmon (Oncorhynchus masou) 2012 4 3 75% 13-16 3 75% 130 - 33 44 - 2013 8 7 88% 13-18 8 100% 12 - 1.5 15 - 2014 5 5 100% 14-16 5 100% <16 - 0 15 - 2015 1 1 100% 16 1 100% <16 - 0 16 - 21 サッパ Japanese shad (Sardinella zunasi) 2012 2 1 50% 15 2 100% 11---9.3 22 サワラ Japanese Spanish mackerel (Scomberomorus niphonius) 2012 2 2 100% 13-17 2 100% <17 - 0 15 - 2013 29 29 100% 13-20 29 100% <20 - 0 16 - 2014 20 20 100% 14-20 20 100% <20 - 0 15 - 2015 19 19 100% 13-18 19 100% <18 - 0 16 - 23 シイラ Mahi-mahi (Coryphaena hippurus) ～2011 1 1 100% - 1 100%

145 1.Inspection Results for Fishery Products in Fukushima Prefecture(Mar.2011-Mar.2016)

Number < Limit of Detection ≦100 Bq/kg Maximum Median Mean(1) Mean(2) Mean(3) Fiscal Item of LOD year Number (%) Number (%) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) samples (Bq/kg) 底層 Bottom layer 32 アイナメ Fat greenling (Hexagrammos otakii) ～2011 177 6 3% - 51 29% 3,000 170 - - 360 2012 292 24 8% 12-19 173 59% 1,300 77 - - 150 2013 336 131 39% 12-20 314 93% 1,700 11 - - 35 2014 341 219 64% 12-20 340 100% 120 - 6.5 17 - 2015 358 305 85% 11-20 358 100% 36 - 1.8 15 - 33 アオメエソ(メヒカリ) Greeneyes (Chlorophthalmus borealis) ～2011 9 3 33% - 6 67% 180 33 - - 68 2012 62 59 95% 12-20 62 100% 9.2 - 0.39 15 - 2013 99 98 99% 13-20 99 100% 11 - 0.11 16 - 2014 43 43 100% 13-19 43 100% <19 - 0 16 - 2015 38 38 100% 13-19 38 100% <19 - 0 16 - 34 アカエイ Red stingray (Dasyatis akajei) ～2011 5 0 0% - 4 80% 250 91 - - 110 2015 4 3 75% 13-16 4 100% 94 - 24 35 - 35 アカガレイ Flathead flounder (Hippoglossoides dubius) ～2011 47 29 62% - 46 98% 120 - 13 23 - 2012 116 82 71% 11-20 116 100% 83 - 7.0 18 - 2013 142 117 82% 12-19 142 100% 66 - 4.0 17 - 2014 240 205 85% 11-19 240 100% 88 - 2.6 16 - 2015 70 68 97% 11-20 70 100% 9.3 - 0.24 15 - 36 アカシタビラメ Red tongue sole (Cynoglossus joyneri) ～2011 15 0 0% - 5 33% 250 150 - - 140 2012 14 1 7% 17 11 79% 180 59 - - 69 2013 9 2 22% 15-17 9 100% 59 20 - - 27 2014 15 7 47% 14-18 15 100% 13 7.6 - - 9.5 2015 15 14 93% 13-19 15 100% 7.2 - 0.48 16 - 37 アカムツ Rosy seabass (Doederleinia berycoides) ～2011 4 1 25% - 4 100% 30 9.1 - - 14 2012 13 12 92% 15-20 13 100% 17 - 1.3 16 - 2013 33 33 100% 12-20 33 100% <20 - 0 16 - 2014 38 38 100% 13-19 38 100% <19 - 0 16 - 2015 48 48 100% 13-20 48 100% <20 - 0 16 - 38 アコウダイ Matsubara`s red rock fish (Sebastes matsubarae) ～2011 1 0 0% - 1 100% 72 72 - - 72 2012 4 0 0% - 4 100% 50 21 - - 25 2015 2 2 100% 14-19 2 100% <19 - 0 17 - 39 アブラガレイ Kamchatla flounder (Atheresthes evermanni) ～2011 5 3 60% - 5 100% 8.7 ---8 2012 8 8 100% 15-17 8 100% <17 - 0 16 - 2013 2 2 100% 16-17 2 100% <17 - 0 17 - 2014 1 1 100% 16 1 100% <16 - 0 16 - 2015 6 6 100% 15-18 6 100% <18 - 0 16 - 40 アブラツノザメ Spiny dogfish (Squalus acanthias) ～2011 5 1 20% - 5 100% 62 27 - - 31 2012 6 3 50% 14-16 6 100% 45---20 2013 28 16 57% 14-20 28 100% 45---12 2014 32 27 84% 13-19 32 100% 17 - 1.9 15 - 2015 29 22 76% 12-19 29 100% 24 - 2.9 15 - 41 アブラボウズ Skilfish (Erilepis zonifer (Lockington) ) 2015 1 1 100% 17 1 100% <17 - 0 17 - 42 アラ Sea-edged perch (Niphon spinosus) 2015 1 1 100% 15 1 100% <15 - 0 15 - 43 イカナゴ Japanese sandlance (Ammodytes personatus) ～2011 16 1 6% - 6 38% 400 120 - - 140 2012 11 3 27% 16-17 11 100% 61 25 - - 29 2013 2 2 100% 16-17 2 100% <17 - 0 17 - 2014 1 1 100% 14 1 100% <14 - 0 14 - 2015 3 3 100% 13-16 3 100% <16 - 0 14 - 44 イシガキダイ Spotted Knifejaw (Oplegnathus punctatus) 2012 4 4 100% 14-17 4 100% <17 - 0 16 - 2013 1 1 100% 17 1 100% <17 - 0 17 - 2015 2 2 100% 13-17 2 100% <17 - 0 15 - 45 イシガレイ Stone flounder (Kareius bicoloratus) ～2011 83 0 0% - 26 31% 1,200 140 - - 210 2012 150 20 13% 13-20 99 66% 1,200 54 - - 100 2013 164 72 44% 9.7-20 155 95% 310 8.6 - - 31 2014 189 129 68% 13-20 183 97% 240 - 13 23 - 2015 189 142 75% 12-19 189 100% 85 - 5 17 - 46 イシダイ Striped beakfish (Oplegnathus fasciatus) 2012 3 1 33% 14 3 100% 22 12 - - 14 2015 1 1 100% 14 1 100% <14 - 0 14 - 47 イズカサゴ Izu scorpionfish (Scorpaena neglecta) 2012 1 1 100% 15 1 100% <15 - 0 15 - 2015 1 1 100% 16 1 100% <16 - 0 16 - 48 イトヒキダラ Threadfin hakeling (Laemonema longipes) 2013 1 1 100% 17 1 100% <17 - 0 17 - 49 イネゴチ Crocodile flathead (Cociella crocodila) 2012 1 1 100% 18 1 100% <18 - 0 18 - 50 イラコアナゴ Longnose eel (Synaphobranchus kaupii) ～2011 2 2 100% - 2 100%

146 1.Inspection Results for Fishery Products in Fukushima Prefecture(Mar.2011-Mar.2016)

Number < Limit of Detection ≦100 Bq/kg Maximum Median Mean(1) Mean(2) Mean(3) Fiscal Item of LOD year Number (%) Number (%) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) samples (Bq/kg) 51 ウケグチメバル Japanese rockfish (Sebastes scythropus) 2012 1 0 0% - 1 100% 14 14 - - 14 2013 1 1 100% 12 1 100% <12 - 0 12 - 2014 1 1 100% 17 1 100% <17 - 0 17 - 2015 1 1 100% 12 1 100% <12 - 0 12 - 52 ウスバハギ Unicorn leatherjacket (Aluterus monoceros) ～2011 1 1 100% - 1 100%

147 1.Inspection Results for Fishery Products in Fukushima Prefecture(Mar.2011-Mar.2016)

Number < Limit of Detection ≦100 Bq/kg Maximum Median Mean(1) Mean(2) Mean(3) Fiscal Item of LOD year Number (%) Number (%) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) samples (Bq/kg) 68 ギンアナゴ Congrid eel (Gnathophis nystromi nystoromi) ～2011 3 0 0% - 1 33% 130 130 - - 96 2012 1 0 0% - 1 100% 24 24 - - 24 69 クサウオ Snailfishes (Liparidae)(Liparis tanakai) ～2011 7 2 29% - 7 100% 39 7.9 - - 17 2012 7 7 100% 13-18 7 100% <18 - 0 16 - 2013 5 5 100% 12-18 5 100% <18 - 0 16 - 2014 5 5 100% 14-16 5 100% <16 - 0 15 - 2015 3 3 100% 15-17 3 100% <17 - 0 16 - 70 クロアナゴ Beach conger (Conger japonicus) 2012 2 0 0% - 2 100% 100 95 - - 95 71 クロウシノシタ Black cow-tongue (Paraplagusia japonica) ～2011 13 0 0% - 6 46% 390 130 - - 160 2012 15 0 0% - 13 87% 270 49 - - 73 2013 10 1 10% 19 10 100% 97 21 - - 34 2014 10 5 50% 14-17 10 100% 16---9.8 2015 10 9 90% 14-20 10 100% 9.5 - 0.95 15 - 72 クロソイ Black rockfish (Sebastes schlegeli) ～2011 15 3 20% - 5 33% 2,200 190 - - 470 2012 43 7 16% 13-18 28 65% 960 62 - - 140 2013 39 15 38% 13-19 35 90% 250 17 - - 41 2014 32 22 69% 13-19 32 100% 100 - 8.3 19 - 2015 48 38 79% 13-19 48 100% 40 - 3.6 16 - 73 クロダイ Japanese black porgy (Acanthopagrus schlegelii) ～2011 10 0 0% - 5 50% 240 110 - - 120 2012 37 4 11% 15-17 30 81% 2,000 59 - - 120 2013 38 6 16% 14-20 34 89% 910 17 - - 61 2014 37 14 38% 13-20 36 97% 510 9.4 - - 27 2015 24 16 67% 12-18 24 100% 54 - 7 17 - 74 クロムツ Japanese bluefish (Scombrops gilberti) ～2011 1 0 0% - 1 100% 99--9 2012 1 1 100% 17 1 100% <17 - 0 17 - 2013 1 1 100% 13 1 100% <13 - 0 13 - 2014 2 2 100% 13-18 2 100% <18 - 0 16 - 75 クロメバル Rockfish (Sebastes ventricosus) ～2011 1 0 0% - 0 0% 280 280 - - 280 76 ケムシカジカ Sea raven (Hemitripterus villosus) ～2011 42 1 2% - 32 76% 710 60 - - 100 2012 96 9 9% 15-20 82 85% 600 32 - - 60 2013 155 95 61% 12-20 155 100% 87 - 7.8 17 - 2014 150 137 91% 11-20 150 100% 20 - 0.82 15 - 2015 130 125 96% 12-20 130 100% 28 - 0.6 15 - 77 コブシカジカ Darkfin sculpin (Malacocottus zonurus) ～2011 1 1 100% - 1 100%

148 1.Inspection Results for Fishery Products in Fukushima Prefecture(Mar.2011-Mar.2016)

Number < Limit of Detection ≦100 Bq/kg Maximum Median Mean(1) Mean(2) Mean(3) Fiscal Item of LOD year Number (%) Number (%) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) samples (Bq/kg) 86 シログチ Drum (Argyrosomus argentatus) ～2011 18 2 11% - 18 100% 79 41 - - 41 2012 61 11 18% 15-18 61 100% 93 15 - - 21 2013 43 34 79% 12-18 43 100% 14 - 2.3 15 - 2014 87 87 100% 11-19 87 100% <19 - 0 15 - 2015 78 77 99% 12-20 78 100% 9.9 - 0.13 15 - 87 シロメバル Rockfish (Sebastes cheni) ～2011 46 1 2% - 8 17% 3,200 420 - - 700 2012 120 0 0% - 25 21% 1,700 250 - - 350 2013 85 7 8% 14-19 44 52% 760 100 - - 160 2014 132 21 16% 14-19 115 87% 330 25 - - 50 2015 110 53 48% 13-19 110 100% 65 7.6 - - 13 88 スケソウダラ Alaska pollock (Theragra chalcogramma) ～2011 25 16 64% - 25 100% 97 - 15 26 - 2012 73 48 66% 13-19 72 99% 110 - 12 23 - 2013 86 82 95% 13-20 86 100% 31 - 0.65 16 - 2014 78 78 100% 12-19 78 100% <19 - 0 16 - 2015 56 56 100% 13-20 56 100% <20 - 0 16 - 89 セトヌメリ Sand dragonet (Repomucenus ornatipinnis) 2012 3 2 67% 15-16 3 100% 7.5 - 2.5 13 - 2013 1 1 100% 15 1 100% <15 - 0 15 - 90 ソウハチ Sohachi flounder (Cleisthenes pinetorum) ～2011 3 0 0% - 3 100% 31 28 - - 23 2012 25 14 56% 13-19 25 100% 33---13 2013 44 43 98% 13-20 44 100% 7.2 - 0.16 16 - 2014 84 83 99% 12-19 84 100% 11 - 0.13 15 - 2015 61 61 100% 12-19 61 100% <19 - 0 16 - 91 チカメキントキ Bigeye (Priacanthus boops) ～2011 1 0 0% - 1 100% 32 32 - - 32 92 チダイ Crimson sea bream (Evynnis japonica) ～2011 26 5 19% - 26 100% 91 20 - - 28 2012 47 23 49% 13-19 47 100% 44 6.8 - - 12 2013 59 56 95% 12-19 59 100% 16 - 0.53 15 - 2014 81 79 98% 12-19 81 100% 14 - 0.29 16 - 2015 71 71 100% 13-20 71 100% <20 - 0 16 - 93 テナガダラ Longarm grenadier (Coelorinchus macrochir) ～2011 1 0 0% - 1 100% 22 22 - - 22 2012 4 2 50% 16 4 100% 10---9.0 94 トラフグ Tiger puffer (Takifugu rubripes) ～2011 1 1 100% - 1 100%

149 1.Inspection Results for Fishery Products in Fukushima Prefecture(Mar.2011-Mar.2016)

Number < Limit of Detection ≦100 Bq/kg Maximum Median Mean(1) Mean(2) Mean(3) Fiscal Item of LOD year Number (%) Number (%) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) samples (Bq/kg) 104 ヒガンフグ Panther puffer (Takifugu pardalis) ～2011 9 1 11% - 5 56% 370 92 - - 110 2012 21 6 29% 13-19 21 100% 98 30 - - 34 2013 9 7 78% 13-17 9 100% 43 - 5.8 18 - 2014 28 25 89% 14-19 28 100% 18 - 1.3 15 - 2015 14 14 100% 12-17 14 100% <17 - 0 15 - 105 ヒラメ Olive flounder (Paralichthys olivaceus) ～2011 258 2 1% - 126 49% 4,500 110 - - 170 2012 387 43 11% 13-19 305 79% 690 41 - - 66 2013 412 198 48% 12-20 405 98% 230 7.7 - - 21 2014 458 343 75% 11-20 458 100% 87 - 4.7 16 - 2015 528 468 89% 11-20 528 100% 74 - 1.9 16 - 106 ヒレグロ Blackfin flounder (Glyptocephalus stelleri) ～2011 4 3 75% - 4 100% 29 - 7.3 19 - 2012 49 46 94% 12-19 49 100% 18 - 0.65 16 - 2013 117 117 100% 12-20 117 100% <20 - 0 15 - 2014 114 113 99% 12-20 114 100% 8 - 0.07 15 - 2015 72 72 100% 11-19 72 100% <19 - 0 15 - 107 ホウボウ Gurnard (Chelidonichthys spinosus) ～2011 44 1 2% - 29 66% 440 79 - - 110 2012 85 34 40% 12-19 83 98% 120 9.4 - - 22 2013 107 78 73% 12-20 106 99% 150 - 5.9 17 - 2014 141 132 94% 12-19 141 100% 10 - 0.51 15 - 2015 148 147 99% 13-19 148 100% 6.7 - 0.045 16 - 108 ホシエイ Pitted stingray (Dasyatis matsubarai) ～2011 1 0 0% - 1 100% 100 100 - - 100 2012 1 0 0% - 1 100% 99 99 - - 99 109 ホシガレイ Spotted halibut (Verasper variegatus) ～2011 5 0 0% - 4 80% 340 58 - - 120 2012 11 2 18% 16 9 82% 570 41 - - 92 2013 23 17 74% 13-18 23 100% 48 - 5.1 17 - 2014 40 38 95% 13-19 40 100% 18 - 0.68 16 - 2015 45 44 98% 13-19 45 100% 6.1 - 0.14 16 - 110 ホシザメ Starspotted smooth-hound (Mustelus manazo) ～2011 17 0 0% - 16 94% 110 51 - - 54 2012 16 2 13% 20 15 94% 180 37 - - 50 2013 24 8 33% 15-19 23 96% 130 11 - - 23 2014 49 27 55% 13-19 49 100% 37---11 2015 45 30 67% 14-20 45 100% 15 - 3.3 14 - 111 ホッケ Arabesque greenling (Pleurogrammus azonus) ～2011 2 2 100% - 2 100%

150 1.Inspection Results for Fishery Products in Fukushima Prefecture(Mar.2011-Mar.2016)

Number < Limit of Detection ≦100 Bq/kg Maximum Median Mean(1) Mean(2) Mean(3) Fiscal Item of LOD year Number (%) Number (%) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) samples (Bq/kg) 119 マダラ Pacific cod (Gadus macrocephalus) ～2011 103 10 10% - 72 70% 300 68 - - 80 2012 216 43 20% 13-19 199 92% 490 26 - - 41 2013 252 149 59% 12-20 250 99% 200---15 2014 296 264 89% 13-20 296 100% 47 - 1.6 16 - 2015 316 309 98% 12-20 316 100% 14 - 0.2 16 - 120 マツカワ Barfin flounder (Verasper moseri) ～2011 2 1 50% - 2 100% 56---32 2012 20 16 80% 13-18 19 95% 140 - 18 30 - 2013 14 11 79% 13-17 14 100% 30 - 3.9 16 - 2014 21 20 95% 13-20 21 100% 7.3 - 0.35 16 - 2015 14 14 100% 14-18 14 100% <18 - 0 16 - 121 マツダイ Tripletail (Lobotes surinamensis) 2015 1 1 100% 17 1 100% <17 - 0 17 - 122 マトウダイ John Dory (Zeus faber) ～2011 51 4 8% - 46 90% 380 39 - - 62 2012 64 27 42% 12-20 64 100% 89 8.8 - - 16 2013 54 43 80% 13-20 54 100% 29 - 2.3 15 - 2014 107 96 90% 12-20 107 100% 19 - 1.1 15 - 2015 124 123 99% 12-19 124 100% 9.2 - 0.074 15 - 123 マフグ Globefish (Takifugu porphyreus) ～2011 7 0 0% - 6 86% 130 70 - - 81 2012 26 22 85% 13-19 26 100% 13 - 1.5 15 - 2013 16 16 100% 12-18 16 100% <18 - 0 15 - 2014 21 21 100% 13-18 21 100% <18 - 0 15 - 2015 22 22 100% 12-19 22 100% <19 - 0 15 - 124 ミギガレイ Rikuzen flounder (Dexistes rikuzenius) ～2011 37 20 54% - 37 100% 31---12 2012 164 140 85% 7.7-20 164 100% 27 - 1.6 15 - 2013 217 211 97% 12-20 217 100% 12 - 0.24 16 - 2014 193 192 99% 11-20 193 100% 6.2 - 0.032 15 - 2015 176 176 100% 11-19 176 100% <19 - 0 16 - 125 ムシガレイ Shotted halibut (Eopsetta grigorjewi ) ～2011 35 7 20% - 30 86% 180 50 - - 57 2012 119 47 39% 13-20 113 95% 580 11 - - 38 2013 147 112 76% 12-19 146 99% 120 - 5.7 17 - 2014 180 161 89% 12-20 180 100% 76 - 1.3 15 - 2015 202 196 97% 12-19 202 100% 30 - 0.37 15 - 126 ムラソイ Brassblotched rockfish (Sebastes pachycephalus ～2011 7 0 0% - 0 0% 870 180 - - 280 pachycephalus) 2012 29 0 0% - 8 28% 1,100 140 - - 230 2013 25 0 0% - 23 92% 160 37 - - 48 2014 26 3 12% 14-17 26 100% 85 17 - - 25 2015 27 14 52% 14-19 27 100% 52---11 128 メイタガレイ Ridged-eye flounder (Pleuronichthys cornutus) ～2011 23 0 0% - 17 74% 470 43 - - 89 2012 38 3 8% 16-18 34 89% 190 28 - - 43 2013 44 28 64% 12-20 44 100% 37 - 6.7 17 - 2014 68 57 84% 12-20 68 100% 26 - 1.8 15 - 2015 60 58 97% 12-19 60 100% 9.2 - 0.27 15 - 129 メダイ Pacific barrelfish (Hyperoglyphe japonica) ～2011 7 3 43% - 7 100% 22 7.2 - - 11 2012 12 12 100% 13-18 12 100% <18 - 0 16 - 2013 15 15 100% 13-18 15 100% <18 - 0 16 - 2014 13 13 100% 13-19 13 100% <19 - 0 15 - 2015 1 1 100% 14 1 100% <14 - 0 14 - 130 ヤナギノマイ Yellow-body rockfish (Sebastes steindachneri) 2015 1 1 100% 15 1 100% <15 - 0 15 - 131 ヤナギムシガレイ Willowy flounder (Tanakius kitaharai) ～2011 54 14 26% - 54 100% 96 18 - - 27 2012 130 62 48% 12-20 130 100% 82 7.1 - - 13 2013 185 149 81% 12-20 185 100% 49 - 2.5 15 - 2014 168 152 90% 11-20 168 100% 33 - 1 15 - 2015 198 190 96% 12-19 198 100% 15 - 0.41 15 - 132 ユメカサゴ Hilgendorf' saucord (Helicolenus hilgendorfi) ～2011 9 3 33% - 9 100% 72 11 - - 30 2012 116 92 79% 12-20 116 100% 46 - 3.4 16 - 2013 293 276 94% 11-20 292 100% 110 - 0.93 16 - 2014 283 275 97% 12-20 283 100% 16 - 0.28 15 - 2015 110 110 100% 13-20 110 100% <20 - 0 16 -

151 1.Inspection Results for Fishery Products in Fukushima Prefecture(Mar.2011-Mar.2016)

Number < Limit of Detection ≦100 Bq/kg Maximum Median Mean(1) Mean(2) Mean(3) Fiscal Item of LOD year Number (%) Number (%) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) samples (Bq/kg) 無脊椎 Invertebrate 133 アサリ Japanese littleneck clam (Venerupis (Ruditapes) ～2011 4 2 50% - 4 100% 96---35 philippinarum) 2012 29 18 62% 13-20 29 100% 27 - 4.9 15 - 2013 32 26 81% 13-20 32 100% 52 - 3.8 17 - 2014 28 28 100% 14-20 28 100% <20 - 0 17 - 2015 42 41 98% 14-19 42 100% 13 - 0.31 16 - 134 アヤボラ Oregon Triton (Fusitriton oregonensis) 2014 7 7 100% 14-17 7 100% <17 - 0 16 - 2015 1 1 100% 17 1 100% <17 - 0 17 - 135 アワビ Abalone (Haliotis sp.) ～2011 24 3 13% - 15 63% 480 80 - - 110 2012 52 45 87% 14-20 52 100% 32 - 1.8 16 - 2013 67 67 100% 12-20 67 100% <20 - 0 16 - 2014 97 96 99% 12-20 97 100% 12 - 0.12 16 - 2015 74 74 100% 13-20 74 100% <20 - 0 16 - 136 イイダコ Ocellated Octopus (Octopus ocellatus) ～2011 4 4 100% - 4 100%

152 1.Inspection Results for Fishery Products in Fukushima Prefecture(Mar.2011-Mar.2016)

Number < Limit of Detection ≦100 Bq/kg Maximum Median Mean(1) Mean(2) Mean(3) Fiscal Item of LOD year Number (%) Number (%) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) samples (Bq/kg) 151 コタマガイ Clam (Gomphina melanegis) 2012 3 3 100% 0 3 100% <16 - 0 14 - 2013 12 12 100% 0 12 100% <20 - 0 17 - 2014 13 13 100% 0 13 100% <19 - 0 16 - 2015 19 19 100% 0 19 100% <19 - 0 16 - 152 サルエビ Cocktail shrimp (Trachypenaeus curvirostris) ～2011 3 1 33% - 2 67% 170 85 - - 88 2012 1 1 100% 0 1 100% <15 - 0 15 - 153 シャコ Mantis shrimp (Oratosquilla oratoria) ～2011 2 0 0% - 2 100% 50 35 - - 35 2012 1 1 100% 0 1 100% <17 - 0 17 - 154 シライトマキバイ Japanese whelk (Buccinum isaotakii) ～2011 5 5 100% - 5 100%

153 1.Inspection Results for Fishery Products in Fukushima Prefecture(Mar.2011-Mar.2016)

Number < Limit of Detection ≦100 Bq/kg Maximum Median Mean(1) Mean(2) Mean(3) Fiscal Item of LOD year Number (%) Number (%) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) samples (Bq/kg) 170 ホタテガイ Scallop (Mizuhopecten yessoensis) ～2011 1 0 0% - 1 100% 19 19 - - 19 171 ボタンエビ Botan shrimp (Pandalus nipponesis) 2012 3 3 100% 0 3 100% <19 - 0 18 - 172 ホッコクアカエビ Alaskan pink shrimp (Pandalus eous) ～2011 6 6 100% - 6 100%

154 1.Inspection Results for Fishery Products in Fukushima Prefecture(Mar.2011-Mar.2016)

Number < Limit of Detection ≦100 Bq/kg Maximum Median Mean(1) Mean(2) Mean(3) Fiscal Item of LOD year Number (%) Number (%) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) samples (Bq/kg) 海藻類 Seaweeds 182 アラメ Arame seaweed (Eisenia bicyclis) ～2011 24 5 21% - 10 42% 970 160 - - 310 2012 2 2 100% 11-18 2 100% <18 - 0 15 - 2013 1 1 100% 9.8 1 100% <9.8 - 0 9.8 - 183 コンブ Sea tangle (Laminaria) ～2011 3 1 33% - 2 67% 110 95 - - 71 2013 1 1 100% 9.9 1 100% <9.9 - 0 9.9 - 184 ヒジキ Hijiki seaweed (Hizikia fusiformis) ～2011 2 0 0% - 0 0% 1,100 610 - - 610 2013 1 1 100% 7.4 1 100% <7.4 - 0 7.4 - 185 ヒトエグサ(養殖) Green laver (farmed) (Monostroma nitidum) ～2011 10 7 70% - 10 100% 47 - 9.7 21 - 2012 19 16 84% 6.3-19 19 100% 12 - 1.3 10 - 2013 17 12 71% 5.2-10 17 100% 21 - 2.2 7.1 - 2014 17 13 76% 6.5-8.9 17 100% 6.1 - 1.1 6.8 - 2015 17 13 76% 5.4-8.9 17 100% 7.2 - 1.5 6.8 - 186 マツモ Rigid Hornwort (Ceratophyllum demersum) ～2011 1 1 100% - 1 100%

155 1.Inspection Results for Fishery Products in Fukushima Prefecture(Mar.2011-Mar.2016)

Number < Limit of Detection ≦100 Bq/kg Maximum Median Mean(1) Mean(2) Mean(3) Fiscal Item of LOD year Number (%) Number (%) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) samples (Bq/kg) 淡水 Freshwater 188 アユ Ayu sweetfish (wild) (Plecoglossus altivelis) ～2011 74 6 8% - 34 46% 4,400 120 - - 490 2012 59 30 51% 13-18 55 93% 280---34 2013 49 25 51% 12-18 48 98% 200---29 2014 63 30 48% 10-19 62 98% 130 11 - - 24 2015 56 24 43% 13-20 55 98% 110 14 - - 27 189 アユ(養殖) Ayu sweetfish (farmed) (Plecoglossus altivelis) ～2011 4 2 50% - 4 100% 17---9.7 2012 4 4 100% 15-17 4 100% <17 - 0 16 - 2013 2 1 50% 14 2 100% 93---50 190 イワナ Whitespotted char (wild) (Salvelinus leucomaenis) ～2011 44 3 7% - 23 52% 590 91 - - 140 2012 161 48 30% 13-19 132 82% 840 28 - - 68 2013 177 48 27% 13-19 162 92% 600 16 - - 38 2014 348 128 37% 12-20 339 97% 740 10 - - 24 2015 168 79 47% 11-19 165 98% 140 8.4 - - 19 191 イワナ(養殖) Whitespotted char (farmed) (Salvelinus leucomaenis) ～2011 90 80 89% - 90 100% 30 - 2.1 16 - 2012 98 98 100% 12-19 98 100% <19 - 0 16 - 2013 98 97 99% 12-20 98 100% 7.3 - 0.074 16 - 2014 99 97 98% 12-20 99 100% 9.3 - 0.16 15 - 2015 80 80 100% 12-19 80 100% <19 - 0 15 - 192 ウグイ Japanese dace (wild) (Tribolodon hakonensis) ～2011 46 3 7% - 31 67% 2,500 83 - - 190 2012 64 9 14% 14-19 51 80% 420 26 - - 66 2013 75 36 48% 13-19 70 93% 390 7.4 - - 29 2014 135 98 73% 12-20 134 99% 130 - 6.9 18 - 2015 60 22 37% 13-19 60 100% 84 13 - - 19 193 ウグイ(養殖) Japanese dace (farmed) (Tribolodon hakonensis) 2014 1 1 100% 16 1 100% <16 - 0 16 - 194 ウチダザリガニ Signal crayfish (Pacifastacus leniusculus) ～2011 2 0 0% - 0 0% 290 250 - - 250 2014 1 0 0% - 1 100% 50 50 - - 50 2015 1 0 0% - 1 100% 11 11 - - 11 195 ウナギ Japanese eel (wild) (Anguilla japonica) ～2011 3 1 33% - 1 33% 140 110--- 2012 3 0 0% - 1 33% 390 140 - - 190 2013 2 0 0% - 1 50% 110 84 - - 84 2014 4 0 0% - 4 100% 76 43 - - 44 196 ギンブナ Silver crucian carp (wild) (Carassius langsdorfii) ～2011 18 2 11% - 13 72% 190 67 - - 78 2012 13 0 0% - 9 69% 310 77 - - 95 2013 17 1 6% 19 12 71% 310 52 - - 89 2014 14 1 7% 13 14 100% 90 37 - - 43 2015 28 9 32% 13-17 28 100% 83 8.7 - - 15 197 ゲンゴロウブナ Japanese crucian carp (wild) (Carassius cuvieri) ～2011 3 0 0% - 2 67% 200 34 - - 88 2012 1 0 0% - 0 0% 170 170 - - 170 2013 2 0 0% - 1 50% 120 94 - - 94 2014 1 0 0% - 1 100% 64 64 - - 64 2015 2 0 0% - 2 100% 24 18 - - 18 198 コイ Common carp (wild) (Cyprinus carpio) ～2011 13 2 15% - 10 77% 160 56 - - 70 2012 23 4 17% 15-17 21 91% 280 29 - - 57 2013 17 1 6% 17 15 88% 110 30 - - 47 2014 11 2 18% 15-17 10 91% 110 17 - - 36 2015 19 4 21% 13-18 19 100% 47 10 - - 15 199 コイ(養殖) Common carp (farmed) (Cyprinus carpio) ～2011 14 6 43% - 14 100% 77 17 - - 25 2012 10 8 80% 14-19 10 100% 7.5 - 1.5 15 - 2013 12 11 92% 14-20 12 100% 7.6 - 0.63 16 - 2014 11 11 100% 14-19 11 100% <19 - 0 16 - 2015 12 12 100% 13-19 12 100% <19 - 0 15 - 200 コクチバス Smallmouth bass (Micropterus dolomieu) ～2011 5 0 0% - 3 60% 330 93 - - 120 201 シロザケ(淡水域) Chum salmon (Freshwater) (Oncorhynchus keta) ～2011 40 39 98% - 40 100% 8 - 0.2 16 - 202 タニシ Mud snail (Cyclophorus spp.) ～2011 2 2 100% - 2 100%

156 1.Inspection Results for Fishery Products in Fukushima Prefecture(Mar.2011-Mar.2016)

Number < Limit of Detection ≦100 Bq/kg Maximum Median Mean(1) Mean(2) Mean(3) Fiscal Item of LOD year Number (%) Number (%) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) samples (Bq/kg) 207 ニジマス(養殖) Rainbow trout (farmed) (Oncorhynchus mykiss) ～2011 17 13 76% - 17 100% 35 - 3.8 16 - 2012 21 21 100% 14-20 21 100% <20 - 0 16 - 2013 24 22 92% 13-18 24 100% 16 - 1.1 16 - 2014 24 21 88% 14-18 24 100% 14 - 1.6 15 - 2015 22 21 95% 13-18 22 100% 8.6 - 0.39 15 - 208 ヒメマス Kokanee (wild) (Oncorhyunchus nerka) ～2011 6 0 0% - 2 33% 160 120 - - 110 2012 10 0 0% - 1 10% 200 140 - - 140 2013 17 0 0% - 9 53% 170 100 - - 110 2014 22 0 0% - 21 95% 110 71 - - 73 2015 26 0 0% - 26 100% 69 30 - - 33 209 ヒメマス(養殖） Kokanee (farmed) (Oncorhyunchus nerka) 2014 1 1 100% 15 1 100% <15 - 0 15 - 2015 1 1 100% 17 1 100% <17 - 0 17 - 210 ホンモロコ(養殖) Willow gudgeon (farmed) (Gnathopogon caerulescens) ～2011 1 0 0% - 0 0% 1,300 1,300 - - 1,300 211 マシジミ Freshwater clam (Corbicula leana) ～2011 2 1 50% - 2 100% 27---18 2013 2 2 100% 14-19 2 100% <19 - 0 17 - 212 モクズガニ Japanese mitten crab (Eriocheir japonica) ～2011 2 0 0% - 0 0% 1,900 1,100 - - 1,100 213 モツゴ(養殖) Topmouth gudgeon (farmed) (Pseudorasbora parva) ～2011 3 0 0% - 2 67% 120 85 - - 89 214 ヤマメ Land-locked salmon (wild) (Oncorhynchus masou) ～2011 69 6 9% - 32 46% 19,000 110 - - 540 2012 120 31 26% 13-19 97 81% 1,400 29 - - 88 2013 145 56 39% 11-19 126 87% 570 11 - - 46 2014 155 50 32% 13-20 141 91% 460 17 - - 38 2015 132 71 54% 12-19 129 98% 180---21 215 ヤマメ(養殖) Land-locked salmon (farmed) (Oncorhynchus masou) ～2011 29 24 83% - 29 100% 35 - 3.0 16 - 2012 21 20 95% 12-19 21 100% 24 - 1.1 16 - 2013 18 18 100% 14-19 18 100% <19 - 0 16 - 2014 22 22 100% 12-18 22 100% <18 - 0 15 - 2015 18 18 100% 13-20 18 100% <20 - 0 16 - 216 ワカサギ Japanese smelt (Hypomesus nipponensis) ～2011 41 2 5% - 4 10% 870 240 - - 290 2012 29 3 10% 15-19 29 100% 76 44 - - 44 2013 13 2 15% 13-15 13 100% 76 19 - - 29 2014 13 1 8% 18 13 100% 42 16 - - 18 2015 7 1 14% 15 7 100% 37 13 - - 17 217 会津ユキマス Peled whitefish (Coregonus peled) 2012 2 2 100% 13-16 2 100% <16 - 0 15 - 218 会津ユキマス(養殖) Peled whitefish (farmed) (Coregonus peled) ～2011 12 10 83% - 12 100% 9.3 - 1.4 15 - 2012 12 11 92% 14-18 12 100% 10 - 0.83 15 - 2013 10 10 100% 15-19 10 100% <19 - 0 16 - 2014 14 14 100% 14-18 14 100% <18 - 0 16 - 2015 4 4 100% 16-17 4 100% <17 - 0 17 -

157 2 Inspection Results for Fishery Products in Other Prefecture than Fukushima（Mar.2011～Mar.2016）

Number < Limit of Detection ≦100 Bq/kg Maximum Median Mean(1) Mean(2) Mean(3) Fiscal Item of LOD year Number (%) Number (%) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) samples (Bq/kg) ごく表層 very surface 1 イシカワシラウオ Ishikawa icefish (Salangichthys ishikawae) ～2011 5 1 20% - 5 100% 4.5 3.3 - - - 2012 14 8 57% 0.98-15 14 100% 7.2 - - - 3.3 2013 3 1 33% 0.98 3 100% 4.0 0.71 - - 1.7 2014 19 12 63% 0.79-13 19 100% 2.4 - 0.35 3.8 - 2015 14 12 86% 0.78-11 14 100% 0.59 - 0.077 5.6 - 2 コウナゴ Japanese sandlance (Ammodytes personatus) ～2011 31 9 29% - 20 65% 1,400 66--- 2012 34 19 56% 0.72-13 34 100% 6.7 - - - 3.6 2013 26 22 85% 0.98-15 26 100% 1.1 - 0.11 6.6 - 2014 32 31 97% 0.67-13 32 100% 0.35 - 0.011 7.4 - 2015 29 25 86% 0.71-14 29 100% 0.69 - 0.083 7.7 - 3 シラウオ Japanese icefish (Salangichthys microdon) ～2011 26 1 4% - 25 96% 2908--- 2012 15 11 73% 3.6-14 15 100% 9 - 1.7 5.6 - 2013 9 4 44% 4-20 9 100% 3.6 0.82 - - 3.1 2014 1 1 100% 20 1 100% <20 - 0 20 - 2015 1 1 100% 20 1 100% <20 - 0 20 - 4 シラス Whitebait ～2011 61 16 26% - 60 98% 180---- 2012 23 17 74% 0.88-20 23 100% 2.8 6 0.24 5.9 - 2013 67 51 76% 0.52-11 67 100% 3.0 - 0.16 2.1 - 2014 60 54 90% 0.71-15 60 100% 1.8 - 0.047 3 - 2015 58 54 93% 0.58-10 58 100% 0.64 - 0.022 3.3 - 5 ノレソレ Conger eel (Juvenile) (Conger myriaster) ～2011 5 0 0% - 5 100% 21 12 - - 11 2012 4 4 100% 1.1-5.4 4 100% <5.4 - 0 3.5 - 2013 2 2 100% 4.7-5 2 100% <5 - 0 4.9 - 2014 3 3 100% 0.62-0.78 3 100% <0.78 - 0 0.68 - 2015 5 5 100% 0.79-15 5 100% <15-05-

158 2 Inspection Results for Fishery Products in Other Prefecture than Fukushima（Mar.2011～Mar.2016）

Number < Limit of Detection ≦100 Bq/kg Maximum Median Mean(1) Mean(2) Mean(3) Fiscal Item of LOD year Number (%) Number (%) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) samples (Bq/kg) 表層 Surface layer 6 アカカマス Red barracuda (Sphyraena pinguis) ～2011 8 1 13% - 8 100% 43 5.1 - - - 2012 13 10 77% 4.9-14 13 100% 1.7 - 0.30 7.0 - 2013 25 13 52% 0.98-13 25 100% 1.8 - - - 2.1 2014 8 8 100% 0.9-12 8 100% <12-06- 2015 11 11 100% 0.91-8.9 11 100% <8.9 - 0 5.9 - 7アカマンボウ Opah (Lampris guttatus) ～2011 1 0 0% - 1 100% 2.4 2.4 - - 2.4 8 ウルメイワシ Round herring (Etrumeus teres) ～2011 3 1 33% - 3 100% 5.5 0.75 - - - 2012 7 4 57% 1.1-8.3 7 100% 2.3 - - - 1.8 2013 10 8 80% 0.87-6.2 10 100% 1.3 - 0.20 2.0 - 2014 6 6 100% 0.78-13 6 100% <13 - 0 4.2 - 2015 1 1 100% 0.89 1 100% <0.89 - 0 0.89 - 9 オオメナツトビ Limpid-wing flyingfish (Cypselurus unicolor) 2012 20 18 90% 1.2-16 20 100% 0.58 - 0.057 9.0 - 2013 9 9 100% 7.6-13 9 100% <13 - 0 10 - 10 カタクチイワシ Anchovy (Engraulis japonicus) ～2011 95 10 11% - 94 99% 170 2.5 - - - 2012 115 58 50% 0.6-13 115 100% 8.6 - - - 1.2 2013 111 96 86% 0.62-10 111 100% 1.7 - 0.099 1.3 - 2014 56 52 93% 0.58-12 56 100% 0.74 - 0.046 1.7 - 2015 11 8 73% 0.54-8.5 11 100% 0.67 - 0.15 2.6 - 11 カツオ Skipjack tuna (Katsuwonus pelamis) ～2011 97 48 49% - 97 100% 33 1.4 - - - 2012 221 200 90% 0.48-20 221 100% 1.7 - 0.061 13 - 2013 159 95 60% 0.6-12 159 100% 3.3 - - - 0.67 2014 72 65 90% 0.61-11 72 100% 0.84 - 0.052 1.4 - 2015 53 45 85% 0.58-13 53 100% 0.77 - 0.076 3 - 12 カマス Barracuda (Sphyraena pinguis) ～2011 1 1 100% - 1 100%

159 2 Inspection Results for Fishery Products in Other Prefecture than Fukushima（Mar.2011～Mar.2016）

Number < Limit of Detection ≦100 Bq/kg Maximum Median Mean(1) Mean(2) Mean(3) Fiscal Item of LOD year Number (%) Number (%) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) samples (Bq/kg) 中層 Intermediate layer 27 アオザメ Shortfin mako shark (Isurus oxyrinchus) ～2011 3 0 0% - 3 100% 224--8.9 2012 21 0 0% - 21 100% 36 4.5 - - 7.4 2013 8 1 13% 1 8 100% 3.0 1.8 - - 1.7 2014 4 1 25% 0.89 4 100% 4.1 1.9 - - 2.1 28 イタチザメ Tiger shark (Galeocerdo cuvier) 2012 1 0 0% - 1 100% 0.79 0.79 - - 0.79 29 オナガザメ Thresher shark (Alopias sp.) 2012 2 0 0% - 2 100% 0.90 0.78 - - 0.78 2014 1 0 0% - 1 100% 5.8 5.8 - - 5.8 30 カマスサワラ Wahoo (Acanthocybium solandri) ～2011 1 1 100% - 1 100%

160 2 Inspection Results for Fishery Products in Other Prefecture than Fukushima（Mar.2011～Mar.2016）

Number < Limit of Detection ≦100 Bq/kg Maximum Median Mean(1) Mean(2) Mean(3) Fiscal Item of LOD year Number (%) Number (%) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) samples (Bq/kg) 47 スズキ Seabass (Lateolabrax japonicus) ～2011 68 1 1% - 53 78% 360 55--- 2012 385 26 7% 4.6-14 368 96% 600 27 - - 38 2013 500 29 6% 1.2-17 498 100% 1,000 12 - - 17 2014 567 127 22% 0.82-15 566 100% 190 4.6 - - 6.7 2015 414 183 44% 0.66-16 414 100% 39 1.5 - - 4.5 48 タカベ Yellowstriped butterfish (Labracoglossa argentiventris) ～2011 1 1 100% - 1 100%

161 2 Inspection Results for Fishery Products in Other Prefecture than Fukushima（Mar.2011～Mar.2016）

Number < Limit of Detection ≦100 Bq/kg Maximum Median Mean(1) Mean(2) Mean(3) Fiscal Item of LOD year Number (%) Number (%) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) samples (Bq/kg) 67 メアジ Bigeye scad (Selar crumenophthalmus) ～2011 1 0 0% - 1 100% 0.65 0.65 - - 0.65 2013 2 1 50% 8.4 2 100% 0.48 - - - 2.3 68 メカジキ Swordfish (Xiphias gladius) ～2011 11 3 27% - 11 100% 4.2 1.6 - - - 2012 22 8 36% 0.74-10 22 100% 3.6 0.69 - - 1.3 2013 9 3 33% 1.2-9 9 100% 1.8 0.74 - - 1.3 2014 3 2 67% 0.76-1.2 3 100% 0.85 - 0.28 0.94 - 2015 2 0 0% - 2 100% 0.39 0.37 - - 0.37 69 メジロザメ Requiem shark 2012 1 0 0% - 1 100% 1.4 1.4 - - 1.4 70 メバチ Bigeye tuna (Thunnus obesus) ～2011 22 2 9% - 22 100% 9.9 2.9 - - - 2012 97 68 70% 0.68-20 97 100% 2.9 - 0.30 12 - 2013 9 3 33% 1-7.7 9 100% 1.1 0.47 - - 1.0 2014 21 9 43% 0.79-1.3 21 100% 1.2 0.46 - - 0.60 2015 15 8 53% 0.67-1.2 15 100% 0.95 - - - 0.57 71 ヨシキリザメ Blue shark (Prionace glauca) ～2011 12 4 33% - 12 100% 5.1 2.5 - - - 2012 27 12 44% 0.82-13 27 100% 2.9 0.61 - - 1.3 2013 10 5 50% 0.73-1.1 10 100% 0.81 - - - 0.50 2014 5 3 60% 0.97-1.2 5 100% 0.78 - - - 0.56 2015 2 2 100% 0.59-0.87 2 100% <0.87 - 0 0.73 -

162 2 Inspection Results for Fishery Products in Other Prefecture than Fukushima（Mar.2011～Mar.2016）

163 2 Inspection Results for Fishery Products in Other Prefecture than Fukushima（Mar.2011～Mar.2016）

Number < Limit of Detection ≦100 Bq/kg Maximum Median Mean(1) Mean(2) Mean(3) Fiscal Item of LOD year Number (%) Number (%) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) samples (Bq/kg) 90 イサキ(養殖) Chicken grunt (farmed) (Parapristipoma trilineatum) 2012 2 2 100% 20 2 100% <20 - 0 20 - 91 イシガキダイ Spotted Knifejaw (Oplegnathus punctatus) 2012 4 4 100% 5.6-11 4 100% <11 - 0 9.0 - 2013 1 1 100% 9.3 1 100% <9.3 - 0 9.3 - 92 イシガレイ Stone flounder (Kareius bicoloratus) ～2011 57 3 5% - 55 96% 180 24--- 2012 163 24 15% 1.3-14 159 98% 230 9.7 - - 19 2013 165 62 38% 0.71-14 165 100% 46 2.4 - - 6.7 2014 129 89 69% 0.99-15 129 100% 65 - 2.6 8.7 - 2015 77 67 87% 0.78-14 77 100% 9.8 - 0.59 8.2 - 93 イシダイ Striped beakfish (Oplegnathus fasciatus) ～2011 3 2 67% - 3 100% 4 - 1.3 - - 2012 1 1 100% 14 1 100% <14 - 0 14 - 2014 5 4 80% 7.3-13 5 100% 0.56 - 0.11 7.6 - 2015 3 3 100% 6.6-9.3 3 100% <9.3 - 0 8.4 - 94 イシモチ Drum (Argyrosomus argentatus) ～2011 1 1 100% - 1 100%

164 2 Inspection Results for Fishery Products in Other Prefecture than Fukushima（Mar.2011～Mar.2016）

Number < Limit of Detection ≦100 Bq/kg Maximum Median Mean(1) Mean(2) Mean(3) Fiscal Item of LOD year Number (%) Number (%) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) samples (Bq/kg) 112 オオクチイシナギ Striped jewfish (Stereolepis doederleini) 2012 1 1 100% 8.4 1 100% <8.4 - 0 8.4 - 2013 4 4 100% 11-15 4 100% <15 - 0 13 - 2014 7 7 100% 7.3-12 7 100% <12 - 0 9.8 - 2015 3 3 100% 8.9-12 3 100% <12 - 0 10 - 113 オキアジ White-tongued crevalle (Uraspis helvola) 2012 1 1 100% 1.1 1 100% <1.1 - 0 1.1 - 114 オキカサゴ Scorpion fish (Halicolenus avius ) 2012 1 1 100% 0.9 1 100% <0.9 - 0 0.9 - 115 オキタナゴ Japanese surfperch (Neoditrema ransonneti) 2012 2 2 100% 9.9-11 2 100% <11 - 0 10 - 116 オキヒイラギ Offshore ponyfish (Equulites rivulatus) ～2011 1 1 100% - 1 100%

165 2 Inspection Results for Fishery Products in Other Prefecture than Fukushima（Mar.2011～Mar.2016）

166 2 Inspection Results for Fishery Products in Other Prefecture than Fukushima（Mar.2011～Mar.2016）

Number < Limit of Detection ≦100 Bq/kg Maximum Median Mean(1) Mean(2) Mean(3) Fiscal Item of LOD year Number (%) Number (%) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) samples (Bq/kg) 135 キチヌ(キビレ) Yellowfin porgy (Acanthopagrus latus) 2013 1 1 100% 6.6 1 100% <6.6 - 0 6.6 - 2014 1 1 100% 4.9 1 100% <4.9 - 0 4.9 - 136 キツネメバル Fox jacopever (Sebastes vulpes) ～2011 7 4 57% - 7 100% 4.6 ---- 2012 63 52 83% 5.7-15 63 100% 81 - 4.9 14 - 2013 56 51 91% 6.1-15 56 100% 58 - 1.5 11 - 2014 74 64 86% 6-15 74 100% 57 - 1.9 11 - 2015 57 53 93% 6-13 57 100% 31 - 0.95 9.9 - 137 ギンアナゴ Congrid eel (Gnathophis nystromi nystoromi) 2013 1 1 100% 9.4 1 100% <9.4 - 0 9.4 - 138 ギンポ Tidepool gunnel (Pholis nebulosa) ～2011 1 0 0% - 1 100% 19 19 - - 19 2012 1 1 100% 5.4 1 100% <5.4 - 0 5.4 - 2013 1 1 100% 7.3 1 100% <7.3 - 0 7.3 - 2014 1 1 100% 7.7 1 100% <7.7 - 0 7.7 - 139 キンメダイ Alfonsino (Beryx splendens) ～2011 33 10 30% - 33 100% 9.8 0.97 - - - 2012 56 8 14% 1.2-14 56 100% 13 2.0 - - 2.7 2013 37 20 54% 0.82-15 37 100% 1.4 - - - 2.1 2014 35 25 71% 0.62-14 35 100% 0.90 - 0.16 5.4 - 2015 24 20 83% 0.59-12 24 100% 0.67 - 0.073 4 - 140 クサウオ Snailfishes (Liparidae)(Liparis tanakai) 2013 3 2 67% 7.3-12 3 100% 0.57 - 0.19 6.6 - 141 クサフグ Grass puffer (Takifugu niphobles) 2013 1 0 0% - 1 100% 8.6 8.6 - - 8.6 2014 4 4 100% 7.3-14 4 100% <14 - 0 10 - 2015 1 1 100% 7.7 1 100% <7.7 - 0 7.7 - 142 クロアナゴ Beach conger (Conger japonicus) 2012 2 0 0% - 2 100% 4.9 4.3 - - 4.3 143 クロウシノシタ Black cow-tongue (Paraplagusia japonica) ～2011 4 0 0% - 4 100% 33 23 - - 21 2012 10 4 40% 6.6-15 10 100% 15 3.4 - - 6.8 2013 9 8 89% 1.1-12 9 100% 0.52 - 0.058 5.6 - 2014 10 10 100% 0.68-13 10 100% <13 - 0 6.2 - 2015 7 7 100% 1.2-14 7 100% <14 - 0 8.5 - 144 クロサバフグ Dark rough-backed puffer (Lagocephalus gloveri) 2014 4 4 100% 8.3-9.4 4 100% <9.4 - 0 8.9 - 2015 1 1 100% 10 1 100% <10 - 0 10 - 145 クロソイ Black rockfish (Sebastes schlegeli) ～2011 12 3 25% - 11 92% 230 5.7 - - - 2012 84 60 71% 6.3-15 83 99% 400 - 9.6 17 - 2013 52 44 85% 0.63-15 52 100% 23 - 1.4 9.8 - 2014 35 32 91% 1.3-14 35 100% 8.3 - 0.53 9.4 - 2015 36 34 94% 0.74-15 36 100% 10 - 0.38 9.3 - 146 クロソイ(養殖) Black rockfish (farmed) (Sebastes schlegeli) 2012 1 1 100% 9.9 1 100% <9.9 - 0 9.9 - 147 クロダイ Japanese black porgy (Acanthopagrus schlegelii) ～2011 3 0 0% - 3 100% 42 29 - - 25 2012 38 10 26% 7.5-14 28 74% 3,300 26 - - 220 2013 66 16 24% 4.8-14 60 91% 310 11 - - 30 2014 74 47 64% 4.8-15 73 99% 110 - 4.9 12 - 2015 33 24 73% 6.5-14 33 100% 7.8 - 1.1 8 - 148 クロメバル Rockfish (Sebastes ventricosus) ～2011 8 0 0% - 7 88% 110 48 - - 50 2012 3 1 33% 11 3 100% 51 30 - - 29 2013 4 3 75% 7.4-14 4 100% 12 - 3.0 10 - 2014 2 1 50% 10 2 100% 5.9 - - - 5.5 149 ケムシカジカ Sea raven (Hemitripterus villosus) ～2011 4 3 75% - 4 100% 17 - 4.3 - - 2012 27 10 37% 8-14 27 100% 38 5.8 - - 11 2013 21 15 71% 6.3-15 21 100% 10 - 1.5 9.0 - 2014 15 15 100% 6.2-13 15 100% <13 - 0 8.8 - 2015 22 22 100% 5.1-12 22 100% <12 - 0 8.7 - 150 ゲンコ Genko sole (Cynoglossus interruptus) 2012 1 0 0% - 1 100% 16 16 - - 16 151 コショウダイ Crescent sweetlips (Plectorhinchus cinctus) ～2011 1 1 100% - 1 100%

167 2 Inspection Results for Fishery Products in Other Prefecture than Fukushima（Mar.2011～Mar.2016）

Number < Limit of Detection ≦100 Bq/kg Maximum Median Mean(1) Mean(2) Mean(3) Fiscal Item of LOD year Number (%) Number (%) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) samples (Bq/kg) 156 コモンフグ Finepatterned puffer (Takifugu poecilonotus) ～2011 6 0 0% - 5 83% 150 88 - - 90 2012 18 5 28% 9.5-15 18 100% 74 10 - - 18 2013 37 24 65% 5.3-14 37 100% 18 - 2.4 8.9 - 2014 17 16 94% 6.1-15 17 100% 6.7 - 0.39 9.5 - 2015 21 21 100% 6.5-13 21 100% <13 - 0 9.1 - 157 サメガレイ Roughscale sole (Clidoderma asperrimum) ～2011 25 16 64% - 25 100% 17 - 2.2 - - 2012 36 33 92% 0.62-15 36 100% 4.7 - 0.24 6.2 - 2013 31 31 100% 0.61-14 31 100% <14 - 0 8.5 - 2014 17 17 100% 0.95-13 17 100% <13 - 0 7.4 - 2015 25 25 100% 0.72-13 25 100% <13 - 0 7.7 - 158 シシャモ Shishamo (Spirinchus lanceolatus) ～2011 8 8 100% - 8 100%

168 2 Inspection Results for Fishery Products in Other Prefecture than Fukushima（Mar.2011～Mar.2016）

Number < Limit of Detection ≦100 Bq/kg Maximum Median Mean(1) Mean(2) Mean(3) Fiscal Item of LOD year Number (%) Number (%) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) samples (Bq/kg) 178 トゲカジカ Great Sculpin (Myoxocephalus polyacanthocephalus) ～2011 9 8 89% - 9 100% 0.46 - 0.051 - - 2012 3 3 100% 1.1-11 3 100% <11 - 0 7.1 - 2013 2 2 100% 5.4-8.3 2 100% <8.3 - 0 6.9 - 2014 1 1 100% 6.6 1 100% <6.6 - 0 6.6 - 2015 1 1 100% 6.8 1 100% <6.8 - 0 6.8 - 179 トビヌメリ Kitefin dragonet (Repomucenus beniteguri) 2013 1 1 100% 11 1 100% <11 - 0 11 - 2014 1 1 100% 13 1 100% <13 - 0 13 - 180 トラザメ Cloudy catshark (Scyliorhimus torazame) 2015 10 10 100% 5.6-11 10 100% <11 - 0 8.7 - 181 トラフグ Tiger puffer (Takifugu rubripes) 2012 8 2 25% 8.6-9.9 8 100% 37 9.1 - - 14 2013 2 1 50% 10 2 100% 11---8 2014 3 3 100% 10-13 3 100% <13 - 0 12 - 182 トラフグ(養殖) Tiger puffer (farmed) (Takifugu rubripes) ～2011 1 1 100% - 1 100% hagfish (Eptatretus burgeri) ～2011 7 7 100% - 7 100%

169 2 Inspection Results for Fishery Products in Other Prefecture than Fukushima（Mar.2011～Mar.2016）

Number < Limit of Detection ≦100 Bq/kg Maximum Median Mean(1) Mean(2) Mean(3) Fiscal Item of LOD year Number (%) Number (%) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) samples (Bq/kg) 200 バラメヌケ Baramenuke rockfish (Sebastes baramenuke) ～2011 1 0 0% - 1 100% 13 13 - - 13 2012 1 0 0% - 1 100% 7.3 7.3 - - 7.3 201 ヒガンフグ Panther puffer (Takifugu pardalis) ～2011 2 0 0% - 2 100% 75 64 - - 64 2012 90 20 22% 7.6-16 88 98% 150 22 - - 32 2013 119 55 46% 5.8-15 119 100% 36 3.0 - - 7.4 2014 22 16 73% 6.8-14 22 100% 22 - 2.1 9.3 - 2015 8 8 100% 7-11 8 100% <11 - 0 8.8 - 202 ヒメダイ Crimson snapper (Pristipomoides sieboldii) 2012 2 2 100% 0.93-11 2 100% <11 - 0 6.0 - 203 ヒモダラ filamented grenadier (Coryphaenoides longifilis) ～2011 1 1 100% - 1 100%

170 2 Inspection Results for Fishery Products in Other Prefecture than Fukushima（Mar.2011～Mar.2016）

Number < Limit of Detection ≦100 Bq/kg Maximum Median Mean(1) Mean(2) Mean(3) Fiscal Item of LOD year Number (%) Number (%) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) samples (Bq/kg) 219 マダイ Red seabream (Pagrus major) ～2011 29 9 31% - 29 100% 39 19--- 2012 58 31 53% 1.1-20 58 100% 40---9.2 2013 56 39 70% 0.92-15 56 100% 8.4 - 0.74 7.5 - 2014 63 58 92% 0.77-14 63 100% 2.1 - 0.079 8.2 - 2015 71 56 79% 0.64-15 71 100% 2.2 - 0.18 6.7 - 220 マダイ(養殖) Red seabream (farmed) (Pagrus major) ～2011 5 5 100% - 5 100% Acanthogobius flavimanus) 2012 5 3 60% 6.4-9.5 5 100% 22---7.8 2014 1 1 100% 11 1 100% <11 - 0 11 - 226 マフグ Globefish (Takifugu porphyreus) ～2011 9 4 44% - 9 100% 49 2.0 - - - 2012 8 8 100% 6.9-16 8 100% <16 - 0 10 - 2013 6 6 100% 8.3-9.8 6 100% <9.8 - 0 9.2 - 2014 6 6 100% 7.5-13 6 100% <13 - 0 9.7 - 2015 7 7 100% 7.4-11 7 100% <11 - 0 9.4 - 227 マルアオメエソ Round Greeneyes (Chlorophthalmus borealis ) 2012 4 0 0% - 4 100% 2.2 1.3 - - 1.4 228 ミギガレイ Rikuzen flounder (Dexistes rikuzenius) ～2011 23 3 13% - 23 100% 137--- 2012 31 15 48% 4.8-14 31 100% 7.9 0.97 - - 4.9 2013 19 19 100% 4-15 19 100% <15 - 0 9.8 - 2014 26 26 100% 6.1-13 26 100% <13 - 0 8.6 - 2015 34 33 97% 1.1-12 34 100% 0.53 - 0.016 8.4 - 229 ムシガレイ Shotted halibut (Eopsetta grigorjewi ) ～2011 43 8 19% - 43 100% 63 19--- 2012 71 34 48% 0.96-15 71 100% 33 3.8 - - 9.1 2013 84 64 76% 0.94-15 84 100% 19 - 1.5 9.1 - 2014 88 83 94% 0.73-15 88 100% 4.7 - 0.11 8.8 - 2015 73 73 100% 0.83-15 73 100% <15 - 0 8.9 - 230 ムツ Gnomefish (Scombrops boops) ～2011 3 1 33% - 3 100% 9.3 1.2 - - - 2012 1 1 100% 11 1 100% <11 - 0 11 - 2013 2 2 100% 8.9-11 2 100% <11 - 0 10 - 2014 3 3 100% 6-13 3 100% <13 - 0 8.6 - 2015 1 1 100% 9.3 1 100% <9.3 - 0 9.3 - 231 ムネダラ Giant grenadier (Albatrossia pectoralis) 2013 1 1 100% 14 1 100% <14 - 0 14 - 232 ムラソイ Brassblotched rockfish ～2011 3 1 33% - 3 100% 34 1.8 - - - (Sebastes pachycephalus pachycephalus) 2012 4 0 0% - 4 100% 33 32 - - 28 2013 16 2 13% 0.95-8.5 16 100% 96 12 - - 23 2014 43 30 70% 6.4-15 43 100% 53 - 5.1 13 - 2015 36 15 42% 6.6-14 36 100% 21 4.5 - - 7 233 メイタガレイ Ridged-eye flounder (Pleuronichthys cornutus) ～2011 14 1 7% - 14 100% 26 15--- 2012 25 13 52% 1-14 25 100% 11---5.6 2013 25 17 68% 0.96-14 25 100% 8.9 - 1.2 7.4 - 2014 11 10 91% 6.8-14 11 100% 0.70 - 0.064 9.5 - 2015 13 13 100% 6.2-14 13 100% <14 - 0 9.4 - 234 メガネカスベ Mottled skate (Raja pulchra) ～2011 1 1 100% - 1 100%

171 2 Inspection Results for Fishery Products in Other Prefecture than Fukushima（Mar.2011～Mar.2016）

Number < Limit of Detection ≦100 Bq/kg Maximum Median Mean(1) Mean(2) Mean(3) Fiscal Item of LOD year Number (%) Number (%) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) samples (Bq/kg) 239 ヤナギノマイ Yellow-body rockfish (Sebastes steindachneri) ～2011 2 1 50% - 2 100% 0.4 ---- 240 ヤナギムシガレイ Willowy flounder (Tanakius kitaharai) ～2011 30 6 20% - 30 100% 40 12--- 2012 44 13 30% 7-15 44 100% 60 6.5 - - 11 2013 37 31 84% 4.9-15 37 100% 9.3 - 1.2 9.4 - 2014 50 49 98% 5.8-14 50 100% 3.8 - 0.076 9.4 - 2015 55 54 98% 5.5-14 55 100% 0.92 - 0.017 8.7 - 241 ヤリヌメリ Spear dragonet (Repomucenus huguenini) 2013 1 1 100% 6.9 1 100% <6.9 - 0 6.9 - 242 ユメカサゴ Hilgendorf' saucord (Helicolenus hilgendorfi) ～2011 14 0 0% - 14 100% 50 14 - - 21 2012 8 3 38% 8.5-14 8 100% 18 4.6 - - 7.9 2013 18 13 72% 5.6-15 18 100% 6.4 - 1.1 8.8 - 2014 19 19 100% 4.9-16 19 100% <16 - 0 9.3 - 2015 23 23 100% 6.1-14 23 100% <14 - 0 9.3 - 243 ヨリトフグ Blunthead puffer (Sphoeroides pachygaster) 2012 1 1 100% 9.3 1 100% <9.3 - 0 9.3 - 2013 1 1 100% 9.8 1 100% <9.8 - 0 9.8 -

172 2 Inspection Results for Fishery Products in Other Prefecture than Fukushima（Mar.2011～Mar.2016）

Number < Limit of Detection ≦100 Bq/kg Maximum Median Mean(1) Mean(2) Mean(3) Fiscal Item of LOD year Number (%) Number (%) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) samples (Bq/kg) 無脊椎 Invertebrate 244 アオリイカ Bigfin Reef Squid (Sepioteuthis lessoniana) 2012 4 4 100% 5.8-9.8 4 100% <9.8 - 0 7.9 - 2013 1 1 100% 8.9 1 100% <8.9 - 0 8.9 - 245 アカイカ Neon Flying Squid (Ommastrephes bartramii) ～2011 10 9 90% - 10 100% 0.57 - 0.057 - - 2012 19 19 100% 0.66-13 19 100% <13 - 0 5.2 - 2013 14 14 100% 0.65-14 14 100% <14 - 0 4.6 - 2014 10 10 100% 0.81-13 10 100% <13 - 0 7.3 - 2015 6 6 100% 0.69-13 6 100% <13 - 0 4.4 - 246 アカガイ Bloody clam (Anadara broughtoni) ～2011 7 5 71% - 7 100% 4 - 0.86 - - 2012 10 9 90% 0.89-8.9 10 100% 7.9 - 0.79 4.4 - 2013 15 13 87% 0.63-8.2 15 100% 1.0 - 0.091 3.1 - 2014 11 11 100% 0.47-11 11 100% <11 - 0 3.8 - 2015 11 10 91% 0.61-6.7 11 100% 0.34 - 0.031 1.3 - 247 アサリ Japanese littleneck clam ～2011 30 22 73% - 30 100% 15 - 2.2 - - (Venerupis (Ruditapes) philippinarum) 2012 52 51 98% 0.44-15 52 100% 11 - 0.21 3.4 - 2013 54 54 100% 0.51-13 54 100% <13 - 0 2.9 - 2014 47 47 100% 0.61-20 47 100% <20 - 0 5.4 - 2015 40 40 100% 0.52-20 40 100% <20 - 0 6.3 - 248 アヤボラ Oregon Triton (Fusitriton oregonensis) ～2011 1 1 100% - 1 100%

173 2 Inspection Results for Fishery Products in Other Prefecture than Fukushima（Mar.2011～Mar.2016）

Number < Limit of Detection ≦100 Bq/kg Maximum Median Mean(1) Mean(2) Mean(3) Fiscal Item of LOD year Number (%) Number (%) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) samples (Bq/kg) 262 クロアワビ(養殖) Japanese abalone (farmed) (Haliotis discus) 2012 2 2 100% 1.1-5.3 2 100% <5.3 - 0 3.2 - 2014 1 1 100% 0.87 1 100% <0.87 - 0 0.87 - 2015 1 1 100% 1.1 1 100% <1.1 - 0 1.1 - 263 ケガニ Horsehair crab (Erimacrus isenbeckii) ～2011 18 18 100% - 18 100%

174 2 Inspection Results for Fishery Products in Other Prefecture than Fukushima（Mar.2011～Mar.2016）

Number < Limit of Detection ≦100 Bq/kg Maximum Median Mean(1) Mean(2) Mean(3) Fiscal Item of LOD year Number (%) Number (%) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) samples (Bq/kg) 280 チヂミエゾボラ Whelk (Neptunea constricta) 2013 4 4 100% 8.5-15 4 100% <15 - 0 12 - 2014 8 8 100% 3.5-13 8 100% <13 - 0 9.1 - 2015 8 8 100% 6-9.8 8 100% <9.8 - 0 8.9 - 281 チョウセンハマグリ Clam (Meretrix lamarckii) ～2011 7 7 100% - 7 100%

175 2 Inspection Results for Fishery Products in Other Prefecture than Fukushima（Mar.2011～Mar.2016）

176 2 Inspection Results for Fishery Products in Other Prefecture than Fukushima（Mar.2011～Mar.2016）

177 2 Inspection Results for Fishery Products in Other Prefecture than Fukushima（Mar.2011～Mar.2016）

178 2 Inspection Results for Fishery Products in Other Prefecture than Fukushima（Mar.2011～Mar.2016）

Number < Limit of Detection ≦100 Bq/kg Maximum Median Mean(1) Mean(2) Mean(3) Fiscal Item of LOD year Number (%) Number (%) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) samples (Bq/kg) 346 ワカメ(養殖) Wakame seaweed (farmed) (Undaria pinnatifida) ～2011 94 93 99% - 94 100% 0.54 - 0.0057 - - 2012 7 7 100% 1.1-11 7 100% <11 - 0 5.0 - 2013 62 62 100% 1.1-20 62 100% <20 - 0 19 - 2014 30 30 100% 0.76-20 30 100% <20 - 0 17 - 2015 26 26 100% 1.1-20 26 100% <20 - 0 19 - 347 岩のり rock seaweed ～2011 1 1 100% - 1 100%

179 2 Inspection Results for Fishery Products in Other Prefecture than Fukushima（Mar.2011～Mar.2016）

180 2 Inspection Results for Fishery Products in Other Prefecture than Fukushima（Mar.2011～Mar.2016）

Number < Limit of Detection ≦100 Bq/kg Maximum Median Mean(1) Mean(2) Mean(3) Fiscal Item of LOD year Number (%) Number (%) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) samples (Bq/kg) 370 ギンブナ Silver crucian carp (wild) (Carassius langsdorfii) ～2011 5 0 0% - 5 100% 78 70 - - 58 2012 72 7 10% 2.4-12 62 86% 240 35 - - 54 2013 67 2 3% 6.2-6.3 61 91% 210 32 - - 44 2014 145 7 5% 7.1-14 141 97% 120 24 - - 27 2015 58 4 7% 3.5-8 57 98% 110 17 - - 22 371 ギンブナ(養殖) Silver crucian carp (farmed) (Carassius langsdorfii) ～2011 1 0 0% - 1 100% 97 97 - - 97 2012 1 0 0% - 1 100% 17 17 - - 17 2014 2 0 0% - 2 100% 8.3 7.2 - - 7.2 372 ゲンゴロウブナ Japanese crucian carp (wild) (Carassius cuvieri) ～2011 5 0 0% - 4 80% 120 100 - - 100 2012 11 0 0% - 11 100% 100 22 - - 44 2013 19 1 5% 8.8 19 100% 55 32 - - 32 2014 32 5 16% 8.9-15 32 100% 34 19 - - 18 2015 16 6 38% 7.4-9.5 16 100% 246--8 373 ゲンゴロウブナ(養殖) Japanese crucian carp (farmed) (Carassius cuvieri) ～2011 1 0 0% - 1 100% 92 92 - - 92 2012 1 0 0% - 1 100% 30 30 - - 30 2014 2 0 0% - 2 100% 17 13 - - 13 374 コイ Common carp (wild) (Cyprinus carpio) ～2011 7 1 14% - 7 100% 89 40--- 2012 32 9 28% 4.9-14 31 97% 330 14--- 2013 32 10 31% 7.1-13 27 84% 220 10 - - 46 2014 44 22 50% 7-13 42 95% 210---20 2015 42 13 31% 4.1-11 40 95% 140 8.3 - - 18 375 コイ(養殖) Common carp (farmed) (Cyprinus carpio) ～2011 16 7 44% - 16 100% 38 7.5 - - - 2012 18 10 56% 6.9-20 18 100% 58---11 2013 20 17 85% 6.4-19 20 100% 6.1 - 0.81 11 - 2014 14 14 100% 7.3-15 14 100% <15 - 0 11 - 2015 12 10 83% 7.2-13 12 100% 5.2 - 0.73 8.7 - 376 サクラマス Cherry salmon (Oncorhynchus masou) 2012 9 6 67% 10-19 9 100% 22 - 6.0 11 - 2013 9 8 89% 2.6-15 9 100% 3.2 - 0.36 9.4 - 2014 4 4 100% 7.4-15 4 100% <15 - 0 11 - 2015 2 2 100% 8.9-11 2 100% <11 - 0 10 - 377 シジミ Brackish-water Clam (Corbicula japonica) 2012 1 1 100% 11 1 100% <11 - 0 11 - 378 シナノユキマス(養殖) Maraena whitefish (farmed) (Coregonus lavaretus maraena) 2012 1 1 100% 7.5 1 100% <7.5 - 0 7.5 - 379 ジュズカケハゼ Chestnut goby (Gymnogobius castaneus) 2012 3 3 100% 10-14 3 100% <14 - 0 12 - 2013 3 3 100% 8.7-12 3 100% <12 - 0 11 - 2015 4 4 100% 7.3-11 4 100% <11 - 0 9.3 - 380 シラウオ Japanese icefish (Salangichthys microdon) ～2011 9 0 0% - 9 100% 63 46 - - 46 2012 58 24 41% 5.8-15 58 100% 38 11 - - 15 2013 41 28 68% 5.8-14 41 100% 26 - 5.2 12 - 2014 41 31 76% 6.5-14 41 100% 14 - 2.6 10 - 2015 38 27 71% 7-12 38 100% 14 - 2.8 9.6 - 381 シロザケ(淡水域) Chum salmon (freshwater) (Oncorhynchus keta) ～2011 12 12 100% - 12 100%

181 2 Inspection Results for Fishery Products in Other Prefecture than Fukushima（Mar.2011～Mar.2016）

Number < Limit of Detection ≦100 Bq/kg Maximum Median Mean(1) Mean(2) Mean(3) Fiscal Item of LOD year Number (%) Number (%) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) samples (Bq/kg) 391 ニジマス(養殖) Rainbow trout (farmed) (Oncorhynchus mykiss) ～2011 40 34 85% - 40 100% 17 - 1.3 - - 2012 97 92 95% 1.7-20 97 100% 18 - 0.52 12 - 2013 80 80 100% 6.1-20 80 100% <20 - 0 12 - 2014 59 58 98% 6.3-15 59 100% 3.1 - 0.053 9.4 - 2015 48 48 100% 6.7-14 48 100% <14 - 0 8.8 - 392 ニジマス・イワナ交配種 Hybrid of whitespotted char and rainbow trout 2015 1 1 100% 7.9 1 100% <7.9 - 0 7.9 - 393 ヌマチチブ Dusky tripletooth goby (Tridentiger obscurus) ～2011 1 0 0% - 1 100% 47 47 - - 47 2012 1 0 0% - 1 100% 18 18 - - 18 2013 2 0 0% - 2 100% 26 26 - - 26 2014 3 0 0% - 3 100% 12 11 - - 11 2015 2 0 0% - 2 100% 15 12 - - 12 394 ヒメマス Kokanee (wild) （Oncorhyunchus nerka) ～2011 5 0 0% - 4 80% 200 54 - - 73 2012 53 11 21% 5.3-13 46 87% 180 14 - - 31 2013 14 6 43% 6.3-14 13 93% 110 4.0 - - 18 2014 11 6 55% 7.5-11 11 100% 100---27 2015 8 5 63% 6.2-9.7 8 100% 49 - 12 17 - 395 ヒメマス(養殖) Kokanee (farmed) (Oncorhyunchus nerka) ～2011 1 1 100% - 1 100%

182 2 Inspection Results for Fishery Products in Other Prefecture than Fukushima（Mar.2011～Mar.2016）

Number < Limit of Detection ≦100 Bq/kg Maximum Median Mean(1) Mean(2) Mean(3) Fiscal Item of LOD year Number (%) Number (%) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) (Bq/kg) samples (Bq/kg) 410 ヨシノボリ Amur goby (Rhinogbius brunneus) 2013 1 0 0% - 1 100% 33 33 - - 33 2014 1 0 0% - 1 100% 14 14 - - 14 411 ワカサギ Japanese smelt (Hypomesus nipponensis) ～2011 71 19 27% - 54 76% 650 42--- 2012 138 52 38% 1.1-19 131 95% 430 18--- 2013 122 62 51% 0.86-17 111 91% 200---33 2014 152 63 41% 0.76-16 150 99% 110 9.5 - - 29 2015 130 50 38% 6.1-13 130 100% 71 15 - - 25 412 奥多摩ヤマメ(養殖) Okutama yamame trout (farmed) (Oncorhynchus masou) ～2011 1 1 100% - 1 100%

183 2 Inspection Results for Fishery Products in Other Prefecture than Fukushima（Mar.2011～Mar.2016）

184