Säteilyturvakeskus Strälsäkerhetscentralen Finnish Centre for Radiation and Nuclear Safety PL-P.O.BOX 268, SF-00101 Helsinki 10, Finland STUK-B-VALO 45 SECOND INTERIM REPORT RADIATION SITUATION IN FINLAND FROM 5 TO 16 MAY 1986 May 1986
Joint report Finnish Centre for Radiation and Nuclear Safety NBC Defence Office of the General Headquarters Rescue Department of the Ministry of the Interior
Helsinki 1986 Government Printing Centre
ISBN 951-46-9578-X ISSN 0781-2868 THE RESULTS IN THIS REPORT HAVE BEEN PREPARED BY
STUK Researchers: Olli Paakkola, Hannele Aaltonen, Hannu Arvela, Leif Blomqvist, Karl-Heinz Hellmuth, Raimo Hentelä, Eero Hiukka, Erkki Hus, Juhani Lahtinen, Heikki Lemmelä, Raimo Mustonen, Marketta Puhakainen, Tua Rahola, Aino Rantavaara, Kristina Rissanen, Laina Salonen, Ritva Saxen, Kari Sinkko, Kirsti- Liisa Sjöblom, Matti Suomela, Tellervo Taipale, Markku Tapiovaara, Kaarina Tevanen, Kaj Winqvist.
Assisting staff: Ritva Aalto, Marjaana Ahonen, Teuvo Ahonen, Esa Eviluoto. Anne-Maaria Hyttinen, Esko Hyttinen, Eija Hämäläinen, Sirkka Hämäläinen, Seppo Klemola, Riitta Kontro, Olli-Matti Lahtimies, Mika Mark kanen, Virpi Nuutinen, Ritva Paatelainen, Anja Pekkala, Teemu Pihkala, Sauli Pusa, Irja Putkonen, Pirkko Saira, Ritva Sarnela, Ulla Välikangas, Timo Ylhäinen.
Text processing: Kristina Rautjärvi. English translation: Ari Penttilä Ministry of the Interior Janne Koivukoski, Juhani Seppä. NBC Defence Office of the General Headquarters
Juhani Juutilainen 1
INTRODUCTION The accident at Chernobyl nuclear power station on 75 April 1986 started an extensive measurement and radiation monitoring program of the environment and foodstuffs, which has demanded the participa tion of most of the personnel and the full ana lysis and measurement capacity of the Surveillance Department of the Finnish Centre för Radiation and Nuclear Safety. This intensive program will still be continued for several months to come. The interim report "Fallout situation in Finland from April 26 to May 4" /l/ treating the weather conditions and radiological measurements of the first week following the accident was published about two weeks after the onset of the accident. This second interim report is a continuation of the first. It deals with the results from external radiation measurements and analysis of environ mental and foodstuff samples between 5 and 16 May, i.e. the development of the situation after the fall-out peak. As in the case of the first report, the results in this report are preliminary, and subsequent checks may cause some changes to them. Each subject matter will later be dealt with in detail in scientific papers, which will be published either as reports of the Finnish Centre for Ra diation and Nuclear Safety or in international scientific periodicals or in conference procee dings . We have considered it necessary to publish the results of the completed measurements and analyses as quickly as possible. We believe that in many sectors it is important to receive early informa tion on the spreading of the fall-out from the failed reactor, as well as an estimate of the doses received. The report also includes a list of the recommendations given in the course of the situation. 2
TAKING OF SAMPLES The first report /l/ gave an outline of the ra diation monitoring network in Finland, and de scribed briefly both STUK's nationwide radiation monitoring program and the environmental monitoring program that is applied in the surroundings of nuclear power plants. The extent of these programs under normal circumstances was explained.
In the present fall-out situation, the sampling frequency and the amounts of samples are many times higher than usually. This applies especially to foodstuffs, but also the numbers of air and deposition samples, as well as certain wild plant samples, have grown considerably.
The control of radioactivity in milk performed by STUK has concentrated on the daily monitoring of milk in the whole of Finland. The monitoring program encompasses 13 dairies, of which about one half are large-scale dairies. In addition, some farm-specific samples have been measured for comparing the iodine contamination in forage and in milk.
Part of the sampling has been channelled through the network of local laboratories that covers the whole country. Th-jre are in total 53 local labo ratories, established by the National Board of Health, working in cooperation with STUK. The laboratories are communal food and milk inspection laboratories and they measure the radioactivity in milk, drinking water and vegetables daily in their own areas and, on request, take environmen tal and foodstuff samples for STUK.
As concerns garden produce and eatable wild plants, the control has been organized in cooperation with the National Board of Trade and Consumer Interests, which takes the samples. During the growing season, all groups of vegetables and fruits are followed extensively in the whole country. The results are assessed separately in each pro duction area.
Besides the sampling performed in accordance with STUK's own monitoring programs and the above- mentioned intensified sampling, the Surveillance Department has received limited amounts of samples of early vegetables produced in some private gardens, as well as samples of other foodstuffs, tap water, well water and mushrooms.
Most of the place-names mentioned in the report are shown on the map in Figure 1. 3
RESULTS External exposure The first report on the Chernobyl accident /l/ described the radiation situation up to the 5th of May. Thereafter the external radiation has been diminishing, as expected. In mid May there were rainy spells in the whole of Finland, but they brought only slight amounts of radioactive substances to the ground. By that time, the air masses had already become almost totally clean. Table 1 shows ~:he daily exposure rates measured at 12 radiation monitoring stations from 5 to 16 May 1986. Figures 2 and 3 illustrate the deve lopment of the exposure rate in five localities. Figure 4 shows a map of the radiation situation on 15 May.
To supplement the results of the measurements performed by the stationary radiation monitoring stations of the Ministry of the Interior and the Defence Forces, the Finnish Centre for Radiation and Nuclear Safety has been mapping the exposure rates by means of sensitive Geiger-counters placed in cars. Figures 5 to 7 show the routes driven and a conclusion of the results.
The gammaspectrometric measurements of the radia tion field were continued by conducting a mapping trip to Central Finland on 6 and 7 May (Figure 7). A spectrometer was measuring all the time inside the car. Additional measurements were made outside the car. On the basis of The measurements it is possible to estimate the contributions of various nuclides to the total exposure rate of the fall-out (Table 2). The table also includes a rough estimate of the activities of various nuclides in the ground. The differences detected in the relative amounts of the nuclides were no longer as great as in the corresponding measure ments performed on 29 April (see /l/, Table 3).
Radiation monitoring flights The daily radiation monitoring flights were con tinued till 11 May with the purpose of surveying radioactivity in the Finnish air space. Special attention was paid to air masses coming from the direction of the accident area and containing the possibility of rain. Air measurements showed that some radioactive substances still came to Finland in the report period but the amounts were no longer significant. 4
Table 3 shows the concentrations of the most important nuclides in the air samples taken during the flights. Air
The national radiation monitoring station of air is situated in Nurmijärvi, where samples are taken with a high-capacity air dust sample collector. In the present fall-out situation, supplementary samples are also taken in Konala, Helsinki, and in Rovaniemi. The samples have been analysed daily.
In Nurmijärvi, the air sample is collected on a glass-fibre filter. Another sample is taken after the air has gone through the filter into an acti vated charcoal cartridge. Since Monday, 28 April, the glass-fibre and charcoal filters have been replaced more often than normally; first twice a day and then once a day. On Monday, 28 April, the taking of air samples was also begun with a smaller collector including a glas-fibre filter, in Konala, Helsinki. Air samples have been taken in Rovaniemi since 6 May.
Table 4 shows the concentrations of radionuclides detected in the air sample collected in Nurmijärvi on 28 April 1986 from 3.00 to 9.00 p.m. During this period, the concentrations of radionuclides reached their maximum value in air. Table 5 gives the concentrations of iodine 131 in air, as de termined by means of the glass-fibre and charcoal filters. The results indicate that, on an average, 85 % of the iodine isotopes have penetrated the glass-fibre filter. The concentrations of iodine given in the tables have been corrected with the measured coefficients of penetration. Table 6 shows the concentrations of various nuclides in ground level air in Nurmijärvi from 28 April to 16 May 1986. Figures 8 and 9 illustrate the deve lopment of the concentrations of iodine 131 and cesium 137 in the same period of time.
Table 7 gives the concentrations of ten radionuc lides in the air in Konala from 5 to 16 May (con tinuation to Table 5 in the previous report /l/). Also in this table, the concentrations of the iodine isotopes have been corrected by assuming that 85 % of the iodine has penetrated the glass- fibre filter.
During the last days of April and the first days of May, small amounts of carbon 14 and tritium were detected in the air samples taken in Konala (Table 8). Thereafter the concentrations have remained below the detection limit. b
Deposition The radionuclide composition of the deposition was followed daily by means of rain water and dry deposition samples taken in Nurmijärvi and in Konala, Helsinki. During dry deposition, the amounts of radioactive substances became smaller, but they rose slightly again due to rains from 10 to 13 May (Table 9). In Figures 10 to 13, the peaks following the maximum deposition were caused by rain. Besides in Nurmijärvi and Konala, changes in the composi tion of deposition were also followed at some other sampling stations by analysing samples at shorter intervals than normally (Table 10). On the basis of the samples taken at the stationary sampling stations in Apri\, the greatest deposi tions of radioactive substances were in Western and Central Finland (cf. Table 11 and /l/ Table 6). Part of the samples have also been analysed for strontium (Table 12), transuranic elements (Table 13), as well as for the total alpha and total beja radiation (Table 14). Surface and drinking waters
The concentrations of iodine 131 and cesium 137 measured in the raw water of some waterworks at the early stages of the fall-out situation are presented in Table 15. Radionuclide concentrations in the raw water for the Espoo and Helsinki wa terworks have been followed regularly. The con centrations of iodine 131 and cesium 137 measured in the samples are shown in Table 16 and the total beta activities measured in two raw water samples from Espoo are given in Table 14.
The gamma nuclide contents in the surface water samples taken from the south of the Baltic Sea and from Lake Päijänne and analysed so far, are presented in Table 17. In the short measurements required by the situation, only minor amounts of iodine 131 were detected in the surface water samples of the Baltic Sea. This is because the fall-out in the sea is rapidly mixed with a great mass of water. The concentrations of long- lived nuclides will be determined by analysing larger volumes of water and by extending the measuring time.
The concentrations of iodine 131 and cesium 137 in the tap water analysed so far are shown in Table 18. Additionally, in total 15 well water samples taken in Southern and Central Finland have been analysed but they have not contained 6
any radioactive substances originating in the fall-out, only small amounts of radon gas. The wells were spring wells or wells walled with concrete rings. Very little radioactivity has been detected in water samples taken from swimming pools.
Grazing grass and wild plants The concentrations of gammanuclides in the samples of grazing grass, sprouts and mosses taken in different parts of Finland are shown in Table 19. Part of the results obtained from plant samples at the early stages of the fall-out situation were already presented in Tables 12 and 13 of the previous report /l/.
The amounts of gamma emitters measured in the fungus Gyromitra esculenta and in nettles are shown in Table 20. The highest concentrations were measured in dried mushrooms, which had been picked right after the maximum fall-out. The table shows the effects of drying and surface contamination on the activity concentration. Most of the surface contamination could be removed in connection with normal household treatment of the mushrooms. According to the recommendation issued by STUK on 7 May 1986, mushrooms and nettles can be eaten a couple of times a week after they have been boiled and the boiling water has been thrown away (cf p. 10).
Foodstuffs The concentrations of iodine 131 in milk in the fall-out area reached their highest values so far in the first or second week in May (Figure 14). Thereafter the values have been steadily decreasing, but they will rise again when the grazing season of the cows is started. The typical maximum readings in the fall-out area were ca. 30 Bq l"1 . One sample from the west of Finland gave the reading 80 Bq 11 . Outside the fall-out area, milk has been almost free from iodine (1 to 5 Bq l"1 ). A slight increase in the cesium 137 activity can also be detected; most findings have, however, been less than 3 Bq l"1 . The concentrations of cesium 134 detected have been much lower still. The transport of strontium from the fall-out to the milk has been almost insignificant (less than 0.05 Bq l*1 ) as cattle has been kept indoors. In the breast milk samples received from the fall out area, the concentrations of iodine 131 were from 1 to 4 Bq 1"1 in the second week of May. 7
Of the Finnish vegetables grown in greenhouses, tomatoes and cucumbers have been practically clean. Similarly, lettuce has been perfectly eatable. All samples have been measured after one rinse.
Early outdoor vegetables, such as parsley, chive and leek, have contained 0.006 to 1.9 kBq of iodine 131 per one kilogram and 0.002 to 0.6 kBq of cesium 137 per one kilogram. The highest concentrations were measured on the first days of May. Rhubarb stalks have been clean.
In the eggs of hens that have been freely fed outdoors, the concentrations of iodine 131 have varied from 0.2 to 3.2 kBq kg-1 and the concent rations of cesium 137 from 16 to 170 Bq kg"1 (eatable part). It has been estimated that in the total production of eggs on sale, the contri bution of the hens that are fed outdoors is neg ligible.
Radioactivity in humans The amounts of radioactive substances accumulated in humans as a consequence of the Chernobyl acci dent have been followed with whole-body counter measurements. People living in Southern Finland as well as tourists and workers returning from abroad, especially from Kiev and from other coun tries in Eastern Europe, have been measured for internal activity. The main emphasis has been placed on iodine 131, which accumulates in the thyroid and is at this stage the most important radioactive substance with respect to the internal radiation dose.
The results from the measurements of people in Southern Finland are presented in Table 21. The amounts of iodine 131 accumulated in the thyroid varied between 0 and 400 Bq. The total dose caused by radioactive iodine to the thyroid varies from 0 to 0.6 mSv. Cesium 137 does not accumulate in any specific organ, but its distribution in the body is fairly homogeneous. The amounts of cesium 137 measured in individuals vary between 0 and 420 Bq. The total dose caused by cesium 137 is a few microsieverts. These dose estimates ignore any radiation doses that may still be caused by radioactive substances accumulating in the body after the measurement.
Table 21 also shows the results from the measure ments of a control group set up by the Finnish Centre for Radiation and Nuclear Safety. Normally there is no radioactive iodine 131 in humans. 8
The measurements of the control group were carried out in 1985 and so they represent the amounts of cesium 137 dating back to the nuclear explosions performed in the 1960s. Special attention has been paid to tourists and workers coming back to Finland from Kiev and other parts of Eastern Europe. In total 101 persons have been measured so far. Table 22 shows the results of the measurements for each area. Only the amounts of iodine 131 measured in the thyroid and the whole-body amounts of cesium 137 are included in the table. In addition, the following radioactive substances were detected in the con taminated persons: Zr-95, Nb-95, Ru-103, 1-132, 1-133, Cs-134, Cs-136, Ba-140, La-140, and Np-239 (Figure 15).
The highest amounts of radioactive substances were detected in persons who had returned from Kiev on 1 May or thereafter. The doses to their thyroids varied between 0.1 and 30 mSv.
ACTION LIMITS AND RECOMMENDATIONS Warning and alarm limits
In the event of a radiation hazard, the authorities participating in radiation control act in accor dance with a guide issued by the Ministry of the Interior /2/. The guide defines the notification and warning limii • to be applied between the various bodies. The institutes taking part in radiation control are the Institute of Seismology, the Finnish Meteorological Institute, the Defence Forces, the Ministry of the Interior, and the Finnish Centre for Radiation and Nuclear Safety.
The continuously operated radiation monitoring stations of the Defence Forces and the Ministry of the Interior are obliged to notify the other institutes participating in the control if the dose rate of external radiation reaches the value 0.07 mR/h, and all radiation monitoring stations are obliged to give a warning to the other bodies if the dose rate reaches the value 1 mR/h. The Finnish Centre for Radiation and Nuclear Safety has the duty to report exceptional findings and to warn the other institutes as deemed appropria te.
According to the guide, population must be warned of a sudden radiation hazard at least when the dose rate has reached the value 20 mR/h. An alarm for seeking immediate shelter must be given at least when the dose rate exceeds the value 200 mR/h. 9
Action limits
The action limits are based on international recommendations concerning the dose limits that can be allowed to the public in an accident si tuation. A recommendation of this kind is Recom mendation no. 40 of the International Commission on Radiological Protection /3/. The recommenda tions give each country a chance to set forth the detailed action limits that are needed, for ins tance, for foodstuffs.
In Finland it has so far been considered necessary to set forth the following action limits. Milk: iodine 131, 2000 Bq l"1 and cesium 137, 1000 Bq l"1 . Rain water used as drinking water: iodine 131, 2000 Bq l"1 .
If the action limit of milk is exceeded, the milk must be used for other purposes than drinking. If the measurements of local laboratories indicate that the total activity of milk exceeds 500 Bq I-1 , the amounts of different radionulices are determined with a gammaspectrometer in the Finnish Centre for Radiation and Nuclear Safety.
If the concentration of iodine 131 in water exceeds 2000 Bq l*1 , the water shall not be used for drinking or for other household purposes. Recommendations
During the fall-out situation, from 28 April to 20 May 1986, the Finnish Centre for Radiation and Nuclear Safety and the other competent autho rities have given a number of recommendations.
The purpose of the recommendations is to prevent all acute effects of the radiation and to restrict the late effects to as few as reasonably achie vable.
Fairly soon after the fall-out had reached Finland, it could be said with certainty that no acute radiation effects were to be expected either from external exposure or from eating and drinking. All recommendations have aimed at reducing the extra radiation exposure of the public.
The following is a list of the recommendations in a chronological order. 1.5. A special Finnair flight to evacuate the about 90 Finns working or studying in Kiev. Activity measurement of the passengers. 10
Local radiation monitoring laborato ries were instructed to begin measu rements . Temporary exclusion limits. Cows shall not be given rain water (2 to 15 May). Rain water shall not be used as drinking water (2 to 15 May). Unnecessary trips to the Ukraine and to the eastern parts of Eastern European countries should be avoided until more information of the situa tion has been obtained (2 to 16 May). Radioactivity measurements of imported foodstuffs are begun. Radiation measurements of vehicles and luggage coming from the Kiev area (6 to 16 May). Cleaning instructions for passengers in case of contamination. If nettles are eaten, they should be boiled and the boiling water should be thrown away. Sowing of lettuce, spinach and other fast-growing vegetables should be postponed (7 to 15 May). Mushrooms should be boiled twice. Children should not play in puddles (7 to 16 May) Cows shall not be let out to pasture (7 to 26 May) Travelling to an area within 50 kilometres from Chernobyl should be avoided. Within 500 kilometres from Chernobyl one should - avoid the use of fresh milk and vegetables - take care of personal hygiene - follow the instructions of local authorities - take a one-time dose of 200 mg of potassium iodide. 8) It was ascertained that - water from wells and waterworks can be used without restrictions - staying outdoors is not restricted - pregnant women need not take any precautions. Nursing is not rest ricted. 10.5. Recommendation to use respire.tors in soil cultivation work. n
12.5. 1) Recommendation to replace air fliters in houses 2) Recommendation that cows are not let out to pasture until 26 May. At the beginning of the grazing season, cows are kept outdoors only for part of the day; forage that has been produced earlier is used for feeding cattle. 13.5. Recommendation to clean transport vehicles and export goods (13 to 19 May). 15.5. 1) Growing of early vegetables can be begun. 2) Rain water can be used normally. 16.5. 1) Mushrooms and plants gathered in the wilds can be eaten. 2) Playing in puddles is allowed. 3) It is no longer necessary to take potassiunm iodide if one travels to an area within 500 km of Chernobyl. 19.5. Recommendation to clean vehicles is cancelled. 12
DOSE ESTIMATE
A preliminary estimate of the average dose and dose commitment in Finland due to the Chernobyl accident has been made on the basis of the map of the radiation situation on 15 May 1986. The estimate comprises external exposure and the in ternal exposure caused by iodine 131 and the cesium isotopes.
In estimating the external radiation dose received up to 15 May, it was assumed that the behaviour of the dose rate follows the curve of Uusikaupunki (see Figure 2). On the basis of the radiation map it was estimated that the average exposure rate, weighted with the population density, is 1/3 of the value in Uusikaupunki. The average shielding factor, which takes into account the roughness of the terrain and the time spent in doors, was assumed to be 0.3.
The predicted external radiation dose in the first year takes into account the seven most important nuclides, as given in Table 2. Of these, only Cs-137 and Cs-134 are affecting the dose in the next year. The exposure rate caused by these diminishes not only because of the physical half- life but also because they are sinking deeper into the ground.
The internal dose accumulated so far has been caused by inhaled iodine 131 in the first days of the fall-out and by iodine 131 in milk. By 16 May, the concentrations in milk were already low enough not to have any significant effect on the dose received. However, there will be a new rise as the grazing of the cows begins. In the dose estimate it is assumed that this will happen on 26 May, in accordance with the recom mendation given on grazing.
The internal dose caused by cesium 137 and cesium 134 is estimated only for the first year. It is estimated that one half of the cesium is received through milk and one half through other foodstuffs.
At this stage it has been considered too uncertain to try to estimate the amounts of radioactivity that will get to foodstuffs through the roots of garden plants and cereal grasses after the first year. However, the situation will be followed as the growing season proceeds.
The dose estimates are presented in Table 23. Consequently, it can be estimated that the Cher nobyl accident will cause an increase of about 0.7 mSv to the average annual radiation dose during 13
the next twelve months in Finland. The average annual dose of about 4.2 mSv will thus increase by 15 to 20 %. When one takes into account all dose pathways, the total dose commitment thaw is received over the years may be of the same magni tude as one year' s average dose from other sources.
REFERENCES
/l/ Interim Report on Fallout Situation in Finland from April 26 to May 4. STUK-B-VALO 44, Helsinki: Finnish Centre for Radiation and Nuclear Safety, 1986.
/2/ Säteilyvalvontaohje viranomaisia varten. Sisäasiainministeriön pelastusosaston julkaisuja 1981:5, Helsinki.
/3/ Protection of the Public in the Event of Major Radiation Accidents: Principles for Planning. ICRP Publication 40, Oxford 1984. 14
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Fig. 7. Measurements of the external exposure rate (pR/h on 6 and 7 May 1186. 21
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mtnv>mtnmintnv> tn tn m tn tr> vi m %r> \n m w- \r> m ci n v tn tf O — Fig. 10. Deposition of iodine 131 in Nurmijärvi Fig. 11. Deposition of cesium 137 in Nurmijärvi from 29 April to 16 May 1986. from 29 April to 16 May 1986. 1-131 deposition Bq m2 Cs-137 deposition Bq m~2 Konala 29.4-16-5.1986 Konala 29.4-16.5.1986 13000 -j 2000 I5000 - I1000 - 1600 10300 - 9000- 8000- 1300 7000- 1000- K> 6000- 5000- J 4000- 600 - 200 - mmmminnmtnin Wl tn V» in m tn m — c< r> *• m tp K. a a o - cv m ^r tn ui I Fig. 12. Deposition of iodine 131 in Konala, Fig. 13. Deposition of cesium 137 in Konala, Helsinki, from 29 April to 16 May 1986. Helsinki, from 29 April to 16 May 1986. APRIL-HAY 1986 APRIL-MAY 1986 Areas where milk has been sampled. APRIL-MAY 1986 HAY 1986 Fig. 14. Iodine 131 in milk from 28 April to 17 May 1986 in areas 1, 2, 4 and 5. o ^9 r I I ! ! Wilk«M^Jik Liu uiAui. tall Uu4UftJuttli-lJuHiJu U JOO 30 .20-00 .40.30 .10.00 110 30 JOO. 30 21:0.30 *6C 30 2i0 30 33Ö -D 3.i33 J»,-: 3i CHANNEL -tO' Fig. 15. Gamma spectrum measured of a person coming from Kiev after the Chernobyl accident. The measurement was made with a whole-body counter equipped with a semiconductor detector. The radioactive subs tances that caused the photo peaks are shown in the figure. Channel width 0.5 keV/channel. Measurement time 1000 s. Table 1. Exposure rates measured at radiation monitoring stations (mR/h). Radiation monitoring station Date 5.5. 6.5. 7.5. 8.5. 9.5. 10.5. 11.5. 12.5. 13.5. 14.5. 15.5. 16.5. Background Kerava 0.013 0.011 0.010 0.010 0.008 0.008 0.009 0.007 0.007 0.006 0,006 0.006 0.009 Loviisa 0.024 0.023 0.019 0.017 0.016 0.016 0.016 0.014 0.012 0.012 0.010 0.011 0.014 Uusikaupunki 0.144 0.127 0.109 0.101 0.090 0.079 0.076 0.069 0.065 0.058 0.055 0.051 0.010 Vammala 0.042 0.041 0.040 0.035 0.033 0.032 0.028 0.026 0.025 0.022 0.022 0.024 0.011 Rauna 0.057 0.053 0.048 0.044 0.041 0.036 0.033 0.033 0.030 0.028 0.026 0.026 0.011 Heinola 0.043 0.041 0.038 0.036 0.035 0.031 0.027 0.027 0.024 0.023 0.022 0.020 0.011 Pieksämäki 0.070 0.065 0.060 0.052 0.050 0.047 0.039 0.039 0.037 0.034 0.034 0.032 0.011 Seinäjoki 0.045 0.041 0.035 0.034 0.030 0.028 0.025 0.026 0.023 0.023 0.021 0.020 0.009 Kokkola 0.023 0.020 0.018 0.018 0.018 0.015 0.013 0.013 0.012 0.011 0.011 0.011 0.009 Ylivieska 0.004 0.004 0.003 0.003 0.003 0.003 0.003 0.002 0.003 0.003 0.003 0.U03 0.009 Raahe 0.002 0.001 0.002 0.002 0.001 0.001 0.001 0.001 0.001 0.001 0.002 0.004 0.009 Kuusamo 0.004 0.005 0.001 0.005 0.0 0.001 0.001 0.001 0.0 0.001 0.002 0.0 0.009 The readings were recorded each day at noon, except on 16 May when they were recorded at 9.00 a.m. The share of background radiation has been deducted. 28 Table 2. Estimates basad on direct spectrometric measure ments in Southern Finland on 6 and 7 May 1986. Nuclide Contribution Activity of to dose rate ground % Bq nr2 Ru-103 2 1 400 - 11 000 J-131 14 1 000 - 60 000 Te-132 3 4 000 - 29 000 J-132 32 4 800 - 32 000 Cs-134 17 900 - 24 000 Cs-137 11 3 000 - 40 000 La-140 21 1 600 - 16 000 Table 3. Ganrce nuclide concentrations in air samples taken during radiation monitoring flights (Bq m-3). Time Place Altitude Zr-95 Ru-103 1-131 Te-132 I-H3 Cs-134 Cs-136 Cs-137 Ba-140 Np-239 29.4. Helsinki, east 1 500 27 1 760 370 194 88 30 155 42 15 30.4. Kotka 50 - 0.02 12.2 0.34 0.8 1 0.095 0.025 0.16 0.19 3C.4. Lahti, north 1 500 - 0.24 9.6 1.8 0.6 0.42 0.19 0.70 0.33 30.4. Helsinki, west 1 000 - 0.12 10.0 0.95 0.5 9 0.12 0.058 0.22 0.18 5.5. Lahti, east 300 - 0.046 1.1 0.023 - - - 0.048 - 5.5. Lahti, east 2 000 - - 0.49 - - - 0.016 - 8.5. The Baltic Sea 500 - 0.039 1.6 0.027 - 0.020 - 0.043 - 8.5. Salo, south 2 700 - 0.103 6.2 0.079 - 0.039 - 0.092 - 8.5. Kouvola, south 1 700 - 0.055 1.0 0.039 - 0.031 0.000044 0.054 0.015 9.5. The Gulf of Finland 1 000 - 0.074 2.2 0.056 - 0.032 - 0.089 9.5. The Baltic Sea 500 - 3.9 12.2 1.1 - 0.30 0.054 0.48 0.24 9.5. Salo, south 2 700 - 0.012 0.3 0.013 - - - 0.012 - 10.5. Hanko, east 500/1500/2500 0.013 1.2 2.5 0.27 - 0.084 0.027 0.15 0.093 10.5. Turku, NE 1 500 - 0.0058 0.12 0.0039 - 0.0050 - 0.0073 - 11.5. Hanko, east 1000/1500 - 0.0086 0.057 0.0044 - 0.0060 - 0.010 0.015 11.5. Tampere, south 1 500 - 0.0084 0.081 0.0056 - - 0.0089 - 0.020 30 Table 4. Concentrations of radionuclides determined up to 16 May 1986 from an air dust sample taken in Nurmijärvi on 28 April 1986 from 15.00 to 21.00 hrs. Nuclide Concentration in air mBq nr3 Zr-95 390 Nb-95 800 Mo-9 9 2 500 Ru-103 3 140 Ru-106 750 Cd-115 770 Sb-125 250 Sb-127 1 690 Te-129m 2 700 Te-131m 1 200 Te-132 36 000 1-131 226 000 1-133 60 000 Cs-134 7 640 Cs-136 3 190 Cs-137 12 500 Ba-140 6 600 Ce-141 590 Ce-144 420 Np-239 3 350 Ag-110m 100 Am-241 20 Cm-242 2 31 Table 5. Concentrations of iodine 131 in a glass-fibre filter and in the subsequent activated charcoal cartridge (mBq nr3 ). Place Time Charcoal Glass-fib re Penetratio cartridge filter (%) Nurmijärvi 29.4.-2.5. 3 490 639 85 n 2.5.-3.5. 1 650 196 89 it 3.5.-4.5. 1 470 26L 85 it 4.5.-5.5. 1 110 195 85 n 5.5.-6.5. 623 112 85 *• 6.5.-7.5. 386 124 76 •• 7.5.—8.5. 494 128 79 n 8.5.-9.5. 428 73.3 85 n 9.5.-10.5. 280 70.0 80 ii 10.5.-12.5. 260 30.3 90 " 12.5.-13.5 155 18.5 89 ft 13.5.-15.5 76.3 4.9 94* ii 15.5-16.5. 67.4 4.7 93* Konala O • 3 • ~~ *t • 3 • 1 370 264 84 n 4.5.-5.5. 976 171 85 ft 5.5.-6.5. 400 105 79 32 Table 6. Concentrations of various radionuclides in surface air in Nurmijärvi frgn 28 April to 16 Niy 1986 (oft) «r3) Fran lb Zr-95 Ri-103 1-131 -»-132 I- 133 C»-134 Cs-136 CS- 137 Ba-140 (f>-239 28.4.86 09.35 28.4.86 15.10 160 390 51 900 3 400 1 3 w 820 320 1 400 1 ;ou 930 28.4.86 15.10 28.4.86 22.10 350 2 400 205 000 :3 2 000 44 555 6 500 2 600 10 000 7 100 3 400 28.4.86 22.10 29.4.86 08.50 210 220 7 300 890 1 330 180 70 320 450 1 200 29.4.86 09.0S 29.4.86 15.45 76 71 5 200 180 665 50 19 91 140 400 29.4.86 15.45 30.4.86 09.20 4.6 100 7 300 760 645 94 34 150 130 39 30.4.86 09.20 30.4.86 15.45 - 9.8 5 300 110 326 26 11 44 38 - 30.4.86 15.45 01.5.86 15.45 0. 77 23 2 900 170 120 51 18 84 45 6.9 01.5.86 16.40 02.5.86 15.55 C. 42 18 3 300 98 60 28 9.7 49 18 - 02.5.86 16.05 03.5.86 13.50 - 3.6 1 330 20 15 7.4 2.5 13 4.3 - 03.5.86 14.10 04.5.86 14.35 - 13 1 730 66 10 33 9.9 56 16 - 04.5.86 14.45 05.5.86 15.15 - 8.7 1 300 33 - 20 6.1 35 8.6 3.1 05.5.86 15.25 06.5.86 15.00 >0. 1 2.6 740 7. 8 - 5.4 1.5 9.1 2.5 - 06.5.86 15.10 07.5.86 13.25 - 5.5 510 6. 0 - 3.5 1.2 6.1 2.7 - 07.5.86 13.35 08.5.86 14.45 2. 16 15.8 620 15.8 - 7.2 2.0 12.6 7.7 - 08.5.86 14.55 09.5.86 14.10 >0.6 24.4 500 20. 7 - 9.6 2.5 17.4 8.9 - 09.5.86 14.10 10.5.86 13.00 0. 29 68.2 350 26. 2 - 10.3 2.5 18.3 10.0 - 10.5.86 14.15 11.5.86 15.40 >0..1 3 38 307 9.8 - 4.1 1.1 7.5 2.9 - 11.5.86 15.45 12.5.86 14.20 - 30.1 299 5. .7 - 2.9 0.82 5.4 1.63 - 12.5.86 14.30 13.5.86 13.15 - 199 174 2. 70 - 4.0 0.87 7.5 0.75 - 13.5.86 13.20 15.2.S6 09.30 - 1.13 81 0. ,31 - 0.52 0.07 0.94 0.19 - 15.5.86 09.30 16.5.86 13.05 - 0.87 72 0. 19 - 0.39 0.07 0.70 - - Ifeble 7. Cbncentrations of various radionuclides in surface air in Konala, Helsinki from 5 to 16 May 1986 (mBq m~3j Prom It. Zr-95 »1-103 1-131 Te-132 1-133 CS-134 Cs-136 Os- 137 BB-140 Np-239 05.5.86 08.20 Ob.5.86 12.50 - 21 1 890 32 21.1 4.9 33.0 11.0 05.5.86 12.50 05.5.86 17.30 - 6.7 1 460 22 15.6 4.0 24.8 <11.0 05.5.86 17.30 05.5.86 20.50 - 4.2 1 220 16 - 2.6 <12.8 - 05.5.86 20.50 06.5.86 07.55 - 3.3 851 10 - 2.0 11.7 - 06.5.86 07.55 06.5.86 13.30 - 3.3 1 140 8.9 6.7 3.0 12.1 3.8 06.5.86 13.30 06.5.86 17.50 - 3.8 1 200 9.2 8.7 2.8 13.9 5.5 06.5.86 17.50 06.5.86 21.30 - 2.9 1 030 8.5 4.5 - 8.3 - 06.5.86 21.30 07.5.86 07.30 3 1.5 718 5.3 4.4 - 7.2 4.3 07.5.86 07.30 07.5.86 11.30 - 4.9 1 530 7.4 - - 7.7 - 07.5.86 11.30 07.5.86 20.55 3.4 12 1 530 12 6.6 1.6 11.0 6.1 07.5.86 20.55 08.5.86 08.30 2.9 4.9 580 6.4 5.7 - 8.9 8.3 08.5.86 08.30 08.5.86 20.30 - >12 644 13 7.2 2.0 13.3 4.6 08.5.86 20.30 09.5.86 08.30 - 27 386 25 11.1 3.3 18.7 8.9 09.5.86 08.30 09.5.86 12.30 - 31 440 25 12.6 4.0 21.1 13.8 09.5.86 12.30 09.5.86 20.15 32 680 26 13.6 4.4 23.0 13.7 OJ.5.86 20.15 10.5.86 08.25 - 28 370 14 6.8 1.8 12.0 6.9 10.5.86 08.30 10.5.86 15.45 - 266 720 71 23.6 3.9 45 16.5 10.5.86 15.45 11.5.86 10.45 - 18 194 4.3 2.7 0.41 4.5 1.2 11.5.86 10.50 12.5.86 07.50 - 39 192 7,8 3.4 - 6.5 2.6 12.5.86 07.50 12.5.86 16.20 - 42 228 7.1 - - 6.7 - 12.5.86 16.20 13.5.86 10.00 21 113 3.0 1.4 0.65 2.5 - 13.5.86 10.00 14.5.86 10.10 - 0.55 67 0.18 - - 0.56 - 14.5.86 10.10 15.5.86 09.55 - 0.87 95 0.33 0.57 - I.- - 15.5.86 10.00 16.5.86 10.00 - 1,1 103 0.22 0.65 - 1.1 0.4- 16.5.86 10.00 1/.5.86 10.00 - 0.92 44 0.22 0.71 _ 1.1 . 33 Table 8. Concentrations of 14 C and 3H in air from 29 April to 13 May 1986 in Konala, Helsinki. Sanpling time 14C OUKJUlLLdLiOn 3H concentration 3H ooncentr. As OOj As hydro As water As gaseous As water carbons 3 3 hydrogen 1 Bq nr Bq nr Bq nr3 Bq nr3 Bq r HjO 29.4. 12.35-15.55 0.82 n 0.78 n 170 29.4. 16.30-21.30 0.54 n 0.62 n 76 29.4.- 30.4. 21.30-19.10 0.078 n 1.6 n 350 30.4.- 1.5. 20.00-11.30 0.21 n 1.6 n 340 1.5.- 2.5. 13.00-13.00 a a a a a 2.5.- 3.5. 16.00-16.40 a a a a a 3.5.- 5.5. 17.40-11.35 a a a a a 5.5.- 6.5. 13.10-14.00 a a a a a 6.5.- 7.5. 15.35-13.55 a a a a a 7.5.- 9.5. 15.05-13.00 a a a a a 9.5.- 13.5. 14.40-08.05 a a a a a n - not analysed a = below detection limit Reference values: concentration of 14 C in air normally 0.025 Bq nr3 concentration of 3H in rain water 3.0 Bq l*1 (hfcirmijärvi, April 84). 14 Tabla 9. tfepwiticra of 9» «aitt*r» — tmjrmd in Mjuijarvi lam o* collector 1 •?) and in Kerala. Itelsiifci (aro of collector 0.05 •?) fro» 3 to 16 My 1986. Tim of ooUaction 24 h atarting at 3 p.«u lki-103 1-131 Ta-132 Ca-134 G»-136 Oa-137 Ba-140 3.-5.5.86* Nurmijärvi 110 155 240 75 24 130 27 4.-5.5.86 Kuala 24 110 69 - 12 - 5.-6.5.86 (lumijärvi 46 71 81 17 5.1 31 13 Kcnala 11 45 16 8.5 15 6.-7.5.86 Nurni järvi 31 39 36 7.0 5.0 14 Konala 13 63 23 21 7.-8.5.86 Numi järvi 32 41 38 11 3.1 19 Konala 20 56 24 7.2 17 8 -9 6 86 Nurmijärvi 43 55 28 17 4.3 26 16 Koala 5 52 14 9.-10.5.86 Nunni järvi 165 124 67 31 6.2 57 40 Kerala 194 247 76 31 54 10.-11.5.86 Nurmijärvi 580 2 860 522 194 - 359 Kerala 2060238060 2 380 0 391 156 - 300 84 11.-12.5.86 Nurmijärvi 245 228 58 - 7b8 22 Konala 57 56 19 - - 19 12.-13.5.86 Nurmijärvi 180 240 34 14 - 38 Kerala 760 870 102 57 107 13.-14.S.86 Kerala 99 130 46 6.5 - 26 13.-15.5.86*' Nurmijärvi 75 70 14 - 16 33 14.-15.5.86 Konala 31 20 15.-16.5.86 Nurmijärvi 37 81 - 4.2 13 Kanala 24 11 9 N.B. 2-day sanpla 35 Table 10. Supplementary data on the depositions of radioactive substances measured at some sampling stations from 30 April to 12 May 1986 (Bq nr2 ). Nuclide Jokioinen Jokioinen Rovaniemi Rovaniemi Joensuu Apukka Apukka 30.4.-11.5. 11.-12.5. 2.-7.5. 7.-12.5. 1.-2.5. Zr-95 160 140 48 - 85 Ru-103 635 310 480 340 170 1-131 2 500 240 1 670 200 560 Te-132 1 580 140 1 350 97 390 Cs-134 310 300 180 - 79 Cs-136 76 - - - 24 Cs-137 490 470 350 62 160 Ba-140 850 300 480 84 Table 11. Depositions of radioactive substances measured at some stationary sampling stations in April 1986 (Bq nr2 ). Supplementary data to Table 6 in the previous report. Nuclide Lappeenranta Pori Kuhmo Zr-95 - - 2 800 Ru-103 230 11 000 3 600 J-131 8 520 246 000 76 000 Te-132 2 390 120 000 11 000 J-133 Cs-134 652 10 000 3 900 Cs-136 304 3 900 1 300 Cs-137 1 174 20 000 7 100 Ba-140 257 9 000 6 300 Np-239 36 Table 12. Sr-89 ja Sr-90 in deposition samples taken at some sampling stations (Bq nr2 ). Place Time Sr-89 Sr-90 Lappeenranta 1. - 30.4.1986 36 18 Savonlinna 1. - 30.4.1986 9.6 19 Kuopio 1. - 30.4.1986 380 510 Joensuu 1. - 30.4.1986 a a Vaasa 1.4. - 1.5.1986 580 840 Rovaniemi, Apukka 1. - 29.4.1986 3.1 11 Ivalo 1.4. - 1.5.1986 a 3 Jokioinen 14. - 30.4.1986 160 190 Helsinki, Konala 29. - 30.4.1986 74 100 Rovaniemi, Apukka 29.4. - 2.5.1986 6.4 14 Nurmijärvi 1. - 2.5.1986 8.3 21 Nurmijärvi 2. - 3.5.1986 3.7 5.8 Lahti1' 29. - 30.4.1986 280 310 a = below detection limit x> night rain on a tin roof. Results are given as Bq kg-1 37 Table 13. Pu-238, Pu-239,240, Am-241 and Cm-242 in depo sition samples or top layers of snow taken at some sampling stations (mBq m2 ). Place Time Pu-238 Pu-239,240 Am-241 Cm-242 Deposition Jyväskylä1 > 1.-30.4. <10 <15 <15 Riihimäki^2» 29.-30.4. 3+3 8.1+4.4 195+14 Helsinki, Konala 29.-30.4. 30 20 Nurmij ärvi 29.-30.4. 8 6 Nurmijärvi1' 30.4.-1.5. <10 <30 303+31 Snow Lahti3> 29.4. 9+2 16+2 Vaasa 29.4. - 3 Kotka 30.4. 1.3+0.3 4+1 Mikkeli 30.4. 12+3 22+4 Joensuu 30.4. 10 50 X) determined at the Department of Radiochemistry of Helsinki University 2) results given as mBq l"1 3> results given as mBq kg-1 38 Table 14. Total alpha and beta activities in some deposition and raw water samples (units Br; nr2 or Bq l'1 ). Place Total Total alpha beta activity activity Deposition (Bq nr2 ) Lappeenranta 1.-30.4.1986 a 13 000 Savonlinna 1.-30.4.1986 a 5 500 Jyväskylä 1.-30.4.1986 a 25 000 Kuopio 1.-30.4.1986 54 86 000 Joensuu 1.-30.4.1986 a 250 Vaasa 1.4.-1.5.1986 a 88 000 Ivalo 1.4.-1.5.1986 a 300 Jokioinen 14.-30.4.1986 a 88 000 Nurmijärvi 2?.-30.4.1986 0.95 12 000 Nurmijärvi 2.-3.5.1986 0.88 4 000 Helsinki, Konala 29. - 30.4.1986 8 4 900 Rovaniemi, Apukka 29.4.-2.5.1986 a 3 100 Lammi 3.5.1986 a 2 1601' Raw water (Bq l-M: Espoo, Bodom 2.5.1986 a 6.0 Espoo, Dämman 2.5.1986 a 13 a = activity below detection limit 1' result given for one litre 39 Table 15. Concentrations of iodine 131 and cesium 137 in the raw water of some waterworks between 30 April and 5 May 1986 (Bq kg'1 ). Place Time 1-131 Cs-137 Vantaa, Silvola 30.4.86 5.7 0.58 Maarianhamina 30.4.86 5.3 0.67 Punkalaidun 30.4.86 35 16 Vaasa 30.4.86 36 1.8 Oulu 2.5.86 6.4 0.70 Kemi 2.5.86 11 Tornio 5.5.86 11 0.43 Table 16. Concentrations of iodine 131 and cesium 137 measured in the raw water of Helsinki and Espoo from 2 to 12 May 1986 (Bq kg-1 ). 2.5. 3.5. 4.5. 5.5 6.5. 8.5. 9.5. 12.5. 1-131 Espoo, Bodom 10 8.8 9.0 9.3 6.0 6.9 3.9 Espoo, Dämman 25 17 14 9.2 4.3 6.0 5.3 Helsinki, Pitkäkoski 2.5 1.5 - Cs-137 Espoo, Bodom 1.4 1.0 1.5 1.2 1.2 1.2 - 0.29 Espoo, Dämman 2.5 1.0 - - 1.4 0.97 - - Helsinki, Pitkäkoski 40 Table 17. Gamma nuclide concentrations measured in surface water of the Baltic Sea and Lake Päijänne between 29 April and 13 May 1986 (Bq kgr1 ). Place Time Ru-103 1-131 Te-132 Cs- 134 CS-137 The Baltic Sea 56°19.2*N, 19°17.2'' E 29.4.86 - 16 The Baltic Sea 56°17.8'N, 19°59.3'' E 2.5.86 - 5.8 Päijänne, Asikkalanselkä 13.5.86 1.6 12 1 2.2 5.6 Päijänne, Tehinselkä 13.5.86 6.3 0.8 1.3 4.2 41 Table 18. Concentrations of odine 131 and cesium 137 measured in tap water (Bq 1 Place Time 1-131 Cs-137 Helsinki, Konala 3.5.1986 3.4 0.20 Lammi 4.5.1986 3.1 - Helsinki, Pitkäkoski 5.5.1986 3.4 - Espoo, Dämmän 6.5.1986 7.0 0.19 Espoo, Verkko D 6.5.1986 6.5 - Espoo, Rinnekoti 7.5.1986 6.3 - Helsinki, Konala 7.5.1986 3.3 - Helsinki, HKW 8.5.1986 0.98 - Helsinki, HKW 8.5.1986 1.5 - Espoo, Bodom 8.5.1986 4.5 - Espoo, Dämman 8.5.1986 6.5 0.6 Tuusula, Paippinen 9.5.1986 0.83 - Helsinki, Vanhakaupunki 9.5.1986 <1 - Helsinki, Ilmala 9.5.1986 <2 - Helsinki, Alppila II 9.5.1986 <2 - Helsinki, Pitkäkoski 9.5.1986 <2 - Helsinki, Pitkäkoski 12.5.1986 0.1 - Espoo, Bodom 12.5.1986 3.9 0.29 42 Table 19. Amounts of ganra emitters measured in grazing grass, sprouts and.in certain wild plants (Bq sif ), The figures In parentheses are given as &j kg-1. Sanele Zr-95 Ru- 103 1-131 Te-132 Cs-134 Qs-136 Cs-137 Ba-140 t^j-239 Varimla, 30.4-, Sphagnum moss 7 400 8 800 130 000 48 000 15 000 5 300 29 000 12 000 27 000 Pietarsaari, 2.5., dry grass 760 8 200 140 000 57 000 29 000 8 700 51 000 17 000 Riihimäki, 2.5., dry grass 400 4300 42 000 17 000 4800 1400 8600 3000 2600 Kajaani, 2.5., dry grass (1 100) (1 100) (3 700) (1 100) (440) (160) (780) (1 700) (2 000) Kajaani, 2.5., fresh grass (2 100) (2 400) (3 700) (1 500) (410) (130) (780) (1 700) (3 500) Kuusamo, 2.5., dry grass - - 80 3.0 - - - 9.5 Rovaniemi, 2.5., dry grass 32 1 700 240 90 31 150 43 Juupajoki, 2.5., Dicranum iross (6 500) (8 700) (81 000) (22 000) (27 000) (6 700) (48 000) (13 000) Lappeenranta, 6.5., rye sprout (260) (960) (4 400) (1 500) (1 300) (320) (2 400) (620) Loiiraa, 6.5., wheat sprout 100 490 920 680 390 93 69 210 Tantere, 6.5., fresh grass 550 1 300 2 700 1 200 1 800 450 3 400 1 000 580 Äänekoski, 6.5., fresh grass 270 410 2 200 650 1 000 240 1 90C 560 280 Kuopio, 6.5., fresh grass 380 400 2 500 4 500 660 150 1 100 450 230 Turku, 7.5., fresh grass 70 190 640 280 U0 30 200 95 Ihrainen, 7,5., fresh grass 120 320 1 300 410 160 42 320 140 Snlo, 7.5., rye sprout 78 1 300 3 100 1 900 510 120 990 320 Vantaa, 7.5., fresh grass (180) (3 300) (17 000) (4 100) (3 000) (760) (5 500) (1 60C) (570) Loviisa, 7.5., fresh grass 39 320 1 600 400 600 140 1 100 330 Irmtra, 7.5., fresh grass 19 32 420 48 54 14 100 27 Uusikaupunki, 7.5., fresh grass 100 690 2 100 890 320 70 540 240 Eurajoki, 7.5., fresh grass 180 550 570 620 330 71 600 240 150 Heinola, 7.5., rye sprout 23 380 1 600 1 100 1 500 310 2 600 620 39 Numo, 7,5., rye sprout 180 1 300 5 000 1 100 1 700 370 3 000 1 100 Saltvik, 8.5., wheat sprout 450 790 1 900 660 480 100 900 580 94 Tnnhola, 8.5., fresh grass 25 170 790 160 130 41 350 77 Helsinki, 8.5., rye sprout 5.2 110 220 140 120 27 220 (>fl f*>r vyjri tnlK, H. l>. , ftfjuh '/r.iHH 1*|U 9 100 10 000 In <*»J 5 400 1 200 ') 000 J 100 43 Saiple Zr-95 Ri-103 1-131 Te-132 Qi-134 Cs-136 Cs-137 Ba-140 H>-239 Pyhtää, 8.5., fresh grass 170 1 900 6 900 2 700 3 700 790 6 800 1 700 Forssa, 8.5., fresh grass 420 1 100 4800 890 860 190 1500 580 Valkeala, 8.5. fresh grass 55 93 340 71 160 35 300 100 Pori, 8.5., fresh grass 130 970 3 000 1 100 1 100 230 2 100 680 Mänttä, 8.5., fresh grass 13 32 180 47 150 36 290 40 Jyväskylän mlk, 8.5., fresh grass 1 300 1 500 7 100 1 100 2 200 470 3 900 1 500 Savonlinna, 8.5., fresh grass - 18 190 28 60 12 110 23 V&asa, 8.5., fresh grass 82 570 5 300 700 2 000 410 3 600 1 100 Raahe, 8.5., fresh grass - 12 81 11 12 1.7 24 10 Kokkola, 8.5., fresh grass 13 200 1 800 380 570 120 1 100 230 Tornio, 8.5., fresh grass - 70 140 83 27 110 240 33 Loviisa, 9.5., fresh grass 55 370 2 000 340 790 190 1 500 330 Hämenlinna, 9.5., fresh grass 180 770 2 500 670 800 190 1 400 470 Juupajoki, 9.5., fresh grass 4.7 13 53 13 34 7.2 67 12 Turku, 12.5., fresh grass 33 73 15 27 50 52 20 Uisikaupunki, 12.5., fresh grass 42 420 800 140 280 54 550 '90 Loviisa, 12.5. fresh grass 44 980 1 400 230 680 120 1 300 250 Valkeakoski, 12.5., fresh grass 67 420 880 180 690 120 1 400 330 Pietarsaari, 12.5., fresh grass 3.7 160 750 140 590 100 1 100 1 200 Lohja, 14.5., fresh grass 20 600 1 700 180 320 66 630 160 Mellila, 14.5., fresh grass 56 330 740 100 310 58 600 100 Vaimala, 14.5., fresh grass 95 200 320 29 190 38 350 74 Kuopio, 14.5-, fresh grass 71 250 760 47 340 55 620 150 Kckkola, 14.5., fresh grass 15 150 860 73 530 88 1 000 160 Tenhola, 15.5., fresh grass 88 100 300 23 55 94 27 Halikko, 15.5., fresh grass 440 720 1 600 120 270 45 550 290 IVitaS, 15.5., fresh grass 130 2 900 6 700 820 4 600 740 Ö 900 1 400 44 Smple Zr-95 fti-103 1-131 Te-132 CS-134 a-136 Cs-137 B»-140 (f>-239 Riihimäki, 15.5., fresh grass - 32 45 4.3 24 4.3 48 S9. 2 Hämeenlinna, 15.5., fresh grass 12 280 580 56 410 70 830 170 Kouvola, 15.5., fresh grass 14 130 290 25 210 31 390 84 Lappeenranta, 15.5., fresh grass 4C 230 390 40 160 22 320 50 Ijiutra, 15.5., fresh grass - 76 130 6.2 20 _ 39 12 Heinola, 15.5., fresh grass 12 120 310 19 300 49 570 95 Mikkelin mlk, 15.5., fresh grass 21 320 1 600 61 630 110 1 200 180 Vilppula, 15.5., fresh grass 19 36 100 - 94 18 180 25 Maasa, 15.5., fresh grass 4.1 29 180 7.5 130 20 250 50 Iisalmi, 15.5., fresh grass 380 360 230 32 77 13 140 170 Pieksämäki, 15.5., fresh grass 8.3 57 110 9.3 98 18 190 30 Helsinki, 16.5., fresh grass 9.2 210 350 24 220 39 450 67 Vantaa, 16.5., fresh grass 36 550 820 90 300 43 560 130 Jyväskylän mlk, 16.5., fresh grass 370 550 830 45 560 85 1 100 260 Kauhajoki, 16.5., fresh grass 1 000 1 300 000 110 2 000 310 3 900 930 45 1 Table 20. Anounts of itters seasured in certain wild plant* used for mirishsant (Bq kg' ). Saeple Zr-95 RJ-103 1-131 Tte-132 CS-134 Cs-136 CB-137 Ba-140 Morel (Gyrtmitra esculenta) Viljakkala. 30.4.86. dried 680 10 700 131 000 59 000 15 900 4 750 26 300 1L 0 500 Viljakkala, 6.5.86, fresh 330 330 3 150 730 590 135 1 07O 530 Kirkkonani. 8.5.86. fresh - 108 634 130 51 - 103 33 Kirkkorunni, 8.5.86, anae parboiled - 138 237 65 21 - 48 28 Kirkhorumu., 8.5.86, twiae parboiled - 178 203 93 16 - 35 39 Lieksa. 8.5.86, fresh 95 50 150 - - - - - Kitee, 8.5.86, fresh - 6.2 20 - - - 3.1 - Koakenpaa, 10.5.86, fresh 137 201 2 510 165 710 110 1 050 400 Koskenpäa. 10.5.86, boiled 213 292 450 69 187 41 310 320 Kuorevesi, 10.5.86, fresh - 176 1 620 170 429 116 771 105 Kaarina, 12.5.86, fresh - 85 393 51 42 11 83 21.4 Nettle (Utrica dioica) Vantaa, 5.5.86, fresh 134 740 5 080 1 540 800 230 1 430 440 Vantaa, 5.5.86, boiled 160 560 1 060 1 100 390 110 680 380 46 Table 21. Amounts of 1-131 in the thyroids and whole-body amounts of Cs-137 of people living in Southern Finland measured in May 1986 (Bq). The table also shows the results of a control group measured in May - June 1985. Number of Amount of Amount of Cs- 137 persons 1-131 in in tody measured thyroid People in Southern Finland, May 1986 Men 18 100 160 Women 7 85 85 Mean 90 130 Control group, May-June 1985 Men 16 -*> 125 Women 10 -*> 50 Mean - 90 *' Normally there is no iodine 131 47 Table 22. 1-131 and Cs-137 activities in tourists returning fxom the Soviet Union and from other countries in Eastern Europe after the acci dent in Chernobyl (Bq). The table shows the activities at the time of measurement, except for the persons returning from Kiev. Their values have been corrected for radioactive decay to represent the tine of contami nation. Number of Amount of Amount of Cs-137 persons 1-131 in in body measured thyroid mean range mean range The Soviet Union Kiev area 54 6 590 70-19500 690 0-1600 Baltic area (Riga, Valmiera, Vilnius) 120 0-280 50 0-170 Black Sea coast (Yalta, Sochi) 4 70 0-260 150 50-230 Moscow 5 30 0-110 40 0-120 Poland 12 940 100-3900 240 0-720 Czechoslovakia 2 1290-1570 200-260 Hungary 4 210 90-480 50 0-140 Romania 3 210 180-270 120 0-180 Bulgaria 4 200 120-290 160 0-210 48 Table 23. Estimate of the effective doses and dose commitments in Finland due to the Chernobyl accident (mSv). Accumulated Prediction Total 28.4.-15.5.1986 15.5.1986- commitment 15.5.1987 External radiation 0.035 0.2 1.6 Internal radiation - iodine 131 0.03 0.1 0.1 - cesiun 134,137 0.4 >0.4 Total 0.065 0.7 >2.1