Levels in feed and food

ORGANOCHLORINES IN FISH FROM , TRIBUTARIES AND THE RIVER, IRKUTSK REGION, : LEVELS AND RISK ASSESSMENT

Mamontova EA1, Mamontov AA1, Tarasova EN1, McLachlan MS2, Mamontov AM3

1Institute of Geochemistry, Siberian Branch of the Russian Academy of Sciences, 664033, PO Box 421, Irkutsk, Russia; 2Department of Applied Environmental Science, Stockholm University, S-106 91 Stockholm, Sweden; 3Limnological Institute, Siberian Branch of the Russian Academy of Sciences, 664033, Irkutsk, Russia

Introduction Lake Baikal – a World Heritage site – is located in East . More than 330 rivers flow into Lake Baikal1, of which the River is the biggest. The Angara River is the only outflowing river. It has been found that sources of PCBs and PCDD/Fs located on the shore of the Angara River have contaminated a significant part of the terrestrial and aquatic ecosystems of the Lake Baikal Region2,3,4. In addition, organochlorine pesticides were widely used in agriculture in the Irkutsk Region in the past5. Organochlorine pesticides accounted for 30 percent of the 1500-2500 tones of pesticides applied annually during the 1980s5. The aim of this work is to review new data and data obtained previously on the distribution of organochlorine compounds (PCDD/Fs, PCBs, DDT and its metabolites, α- and γ-isomers of HCHs and one of components of chlordane – trans-nonachlor (TNCL)) in fish from Lake Baikal, it’s inflowing rivers (the Upper Angara River and the Selenga River) and the Angara River, and to assess the hazard for human health due to the intake of fish contaminated with these compounds.

Materials and Methods In 1997-2005 fish samples were collected in Lake Baikal, in the deltas of several inflowing rivers (the Upper Angara River and the Selenga River) and along the Angara River with the assistance of fishermen (Table 1, Fig. 1). Special attention was given to Maloe More, a large channel located in the middle part of Lake Baikal. The Maloe More is one of the most important piscatorial areas in Lake Baikal. The fish were wrapped in aluminum foil and frozen until analysis. Several fish were pooled for each sample. Samples were analyzed for PCDD/Fs, HCB, PCBs, p,p’-DDT, o,p’-DDT, p,p’-DDD, p,p’-DDE, α- HCH, γ-HCH and TNCL at the laboratories of the Institute of Geochemistry in Irkutsk (Russia), the Baltic Sea Research Institute Warnemunde (Rostock, Germany), the University of Bayreuth (Germany)6, and in Bashkortostan Regional Ecological Center (Ufa, Russia)7. Published methods were used6,7,8. The calculation of carcinogenic and non- carcinogenic risk was made using the Russian guidance document “Human health risk assessment Fig. 1. Map showing the fish sampling locations in from environmental chemicals” (R 2.1.10.1920-04) Lake Baikal, the deltas of several inflowing rivers, and data about consumption rates of fish by the and the Angara River (the sample numbers are Irkutsk region population from the Regional given in the circles). Committee of Statistics.

Organohalogen Compounds Vol 68 (2006) 1943 Levels in feed and food

Table 1. Description of the fish samples and where they were analyzed (D(1) – the University of Bayreuth (Germany); D(2) – Bashkortostan Regional Ecological Center (Ufa, Russia); Irk – the Institute of Geochemistry in Irkutsk (Russia); Rost - the Baltic Sea Research Institute Warnemünde (Rostock, Germany))

# species N Time of Age, Weight, Length, % lipids PCD PCB HCB OC sampling yr grams cm D/Fs P* 1 grayling 5 2005 nd 410-509 33-34 5.57 Irk Irk 2 grayling 15 1999 2-4 135-270 23,6-30,6 1.8;3.41;3.0 D(2) Rost Rost Irk 4 roach 14 1999 5-12 21-92 10,6-17,3 4.1;4.63;5.8 D(2) Rost Rost Irk 3 perch 6 2003 nd 56-122 14,5-18 2.7 Irk Irk 5 dace 5 2003 nd 48-97 14-17 8.1 Irk Irk 6 bream 5 2003 nd 264-470 24,5-29,5 5.17 Irk Irk 7 roach 5 1999 4-5 131-159 17,8-19,1 4.6; 5.8;6.46 D(2) Rost Rost Irk 8 perch 5 1999 4-5 46-62 14-15 3.17 D(2) 28 roach 12 1998 nd nd 22,5-23,5 1.29 Irk Irk 9 perch 20 1999 4-8 60-105 15-18,8 0.97;2.54;2.7 D(2) Rost Rost Irk 10 roach 10 1999 7-16 132-323 18,9-24,3 2.14;4.6;3.99 D(2) Rost Rost Irk 11 perch 5 1999 4-7 51-309 14-23,5 2.73;2.84;5.1 D(2) Rost Rost Irk 12 grayling 6 1999 2-4 141-235 21,2-25,6 4.55;7.57;9.1 D(2) Rost Rost Irk 13 grayling 2001 nd nd nd 1.96 Rost Rost 14 omul 2001 nd nd nd 3.14 Rost Rost 15 omul 10 1997 2-5 nd nd 3.7 D(1) D(1) D(1) 16 grayling 2000 nd nd nd 4.01 Rost Rost 27 roach 4 1999 9-15 139-296 19,7-25,6 2.93; 2.75 D(2) 17 perch 6 1999 4-6 18,1-23 20,4-25,2 2.11; 2.05 D(2) Rost Rost Irk 18 omul 5 2005 nd 236-270 27-30 3.3 Irk Irk 19 pike, f 1 2005 nd 1304 47 1.68 Irk Irk 20 pike, m 3 2005 nd 430-636 36-39 1.18 Irk Irk 21 white- 8 1998 9-10 730-1500 41,3-45,3 13.75 Irk Irk fish 22 omul 5 1997 8-9 nd nd 7.2 D(1) D(1) D(1) 23 white- 2 1998 10 980-1180 42,6-45 7.55 Irk Irk fish 24 omul 7 1997 6-7 nd nd 4.2 D(1) D(1) D(1) 25 perch 20 1997 4-5 nd nd 2.9 D(1) D(1) D(1) 26 roach 20 1997 6-12 nd nd 2.8 D(1) D(1) D(1) * - organochlorine pesticides (DDT, HCH, TNCL), nd – no data

Results and Discussion The results are presented in Figures 2 and 3. The mean levels of the organochlorine compounds in fish from Lake Baikal and the rivers of the region were 10 pg TEQ/g lipids for PCDD/Fs, 644 ng/g lipids for total PCBs including 230 ng/g lipids for indicator PCBs, 120 ng/g lipids for DDT and its metabolites, 39 ng/g lipids for HCB, 3.6 ng/g lipids for α- and γ-HCHs, and 8.2 ng/g lipids for TNCL. The lowest levels of PCDD/Fs, indicator PCBs, and HCB were found in fish caught in rivers flowing into northern Lake Baikal (0.66 pg TEQ/g lipids, 14 and 6.5 ng/g lipids, respectively). The highest PCDD/F concentrations were found below Ust’-Ilimsk (28 pg TEQ/g lipids) and in Maloe More (18 pg TEQ/g lipids). The higher levels in Ust’-Ilimsk were linked to the pulp and paper mill there. PCDFs contributed most of the PCDD/F TEQ in almost all fish samples. However, in fish sampled below Ust’-Ilimsk PCDD and PCDF contributed about equal parts due to the high levels of 2,3,7,8-TCDD. The reason for the elevated levels in fish sampled in Maloe More is not clear yet.

Organohalogen Compounds Vol 68 (2006) 1944 Levels in feed and food

The PCB levels in fish from Lake Baikal were lower than in fish from the Angara River. PCB levels in fish increased from the source of the Angara River with maximum levels in fish from just below the city of Usol’e-Sibirskoe, which is known as one of the PCB contaminated areas. Then the PCB levels decreased a little along the river with the exception of an increase around the industrial town Bratsk. The HCB levels were similar throughout Lake Baikal and the Angara River, apart from somewhat high levels in fish sampled near Bratsk. DDT and its metabolites and α- and γ-HCH showed no consistent spatial pattern. Comparatively high levels of these pesticides were found in the central part of Lake Baikal, in the Selenga River delta and along the Angara River. The ratios of α-HCH/γ-HCH and p,p’-DDT/p,p’-DDE ranged from 1.1 to 4.8 and from 0.002 to 0.45, respectively. The ratio of DDE /total DDT was 0.46-0.85. The highest DDE/total DDT ratios were found in fish from Lake Baikal and the Angara River upstream of Irkutsk (0.7-0.85). The ratio was 0.46-0.7 in fish sampled below Usol’e-Sibirskoe. This suggests more recent usage of the organochlorine pesticides along the Angara River compared to the Lake Baikal watershed. Another distribution was found for TNCL. TNCL was found in all fish samples from Lake Baikal while it was absent in some samples below Usol’e-Sibirskoe collected in 2003 or detected at levels ten times lower than in fish from Lake Baikal or the Selenga River delta. It is possible that Lake Baikal is the major source of chlordane in the Angara River. Agricultural use of chlordane along the Selenga River could be one of the sources of chlordane to Lake Baikal. The ratio of the mean concentrations of the different contaminants was indicator PCBs : DDTs : HCB : TNCL : HCHs = 1 : 0.63 : 0.18 : 0.06 : 0.02. However, in some samples collected in 1998-1999 in the central part of Lake Baikal, the Selenga River delta, and below Ust’-Ilimsk, the DDT:PCB ratio was 1.42, 1 and 1.76, respectively. It should be noted that a decrease in the levels of DDT and its metabolites was found in fish during the last decade. For example, p,p’-DDE and p,p’-DDT levels in omul from the central part of Lake Baikal in 1993 were equal to 15-58 and 6-21 ng/g wet weight9. In white-fish in 1998 they were 21 and 2.5 ng/g wet weight, while in 2005 the levels in omul were 2.8 and 0.95 ng/g wet weight, respectively. No marked decrease in the levels of other organochlorines was observed. The levels of the investigated compounds did not exceed Russian sanitary standards for freshwater fish for consumption by adults (2 mg/kg wet weight for total PCBs, 0.03 mg/kg for HCHs, 0.3 mg/kg for DDTs, and 11 pg TEQ/g for PCDD/Fs (SanPiN 2.3.31078-01 and GN № 142-9/105)). DDT levels in some fish with high lipid content (white-fish from Lake Baikal, bream from the Angara River, and grayling below Ust’-Ilimsk) exceeded sanitary standards for primary products for the preparation of food for children (0.01 mg/kg). Using average concentrations and the average fish consumption of the local population, the mean daily intake of total PCBs, sum of DDTs and its metabolites, sum of HCHs, HCB, and PCDD/Fs via fish consumption would be equal to 655, 175, 5, 46 ng/day and 15 pg TEQ/day, respectively. This corresponds to 0.47, 0.005, 0.000078, 0.025 and 0.21, respectively, of the reference doses of these compounds (Russian guidance document R 2.1.10.1920-04). This intake would amount to 57 % of the total intake for total PCBs, 65 % for DDT, 1 % for HCHs, 15 % for HCB, and 26 % for PCDD/Fs. The hazard indexes for disturbance of the central nervous system, liver, hormonal status, immune system, and development arising from such a daily intake of these compounds with fish (not considering intake with other categories of food) correspond to 0.47, 0.48, 0.69, 0.47 and 0.68, respectively. The carcinogenic risk amounts to 54 cases per 1 million. PCDFs, PCDDs and PCBs make the main contribution to carcinogenic risk (45, 15, and 34 %, respectively). The data on risk are strongly affected by the assumptions made about the origin of the fish. For example, the hazard index arising for disturbance of the hormonal system will equal to 0.03 if people consume fish from the rivers flowing into northern Lake Baikal, 1 if people consume fish from the Maloe More area, 0.34 if people consume fish from the source of the Angara River, 3.6 if people consume fish below Usol’e-Sibirskoe, and 2.3 if people consume fish below Ust’-Ilimsk. The carcinogenic risk under the same condition will equal 2.5, 106, 26, 146 and 222 cases per 1 million, respectively.

Acknowledgments

We thank the fishermen for their assistance in sampling. The investigation was supported by INTAS 2000-00140 and RFFI-04-05-64870.

Organohalogen Compounds Vol 68 (2006) 1945 Levels in feed and food

Figure 2. PCDD/F6,7, indicator PCBs, HCB, DDTs, HCHs and TNCL levels in fish.

Reference 1. Atlas of Lake Baikal, Galazy GI. (ed.), Moscow, ISBN 5-85120-009-X. 2. Mamontov АA, Mamontova EA, Tarasova EN, McLachlan MS. Environ Sci Technol 2000;34:741. 3. Mamontova EA, Tarasova EN, Mamontov АA, McLachlan MS, Litvintsev AN. Ecological Chemistry 2003;12:47 (in Russian). 4. Mamontova EA, Mamontov AA, Tarasova EN, Kolesnikov SI, Furst P, Papke O, Ryan J, McLachlan MS. Organohalogen Comp 1999;44:37. 5. Savchenkov MF, Ignat’eva LP. The hygiene of application of pesticides in Siberia, Irkutsk University, Irkutsk, 1994, ISBN 5-7430-0434-X 6. Mamontov AA, Mamontova EA, Tarasova EN, McLachlan MS. Organohalogen Comp 1998;39:323. 7. Mamontov АA, Mamontova EA, Tarasova EN, Amirova Z. Organohalogen Comp 2000;46:503. 8. Polychlorinated biphenyls (PCB) in the Lake Baikal Region: source, long transport and risk assessment. Kuzmin MI. (ed.), Publish Office of the Institute of Geography SB RAS, Irkutsk, ISBN 5-94797-073-2. 9. Kucklick JR, Harvey R, Ostrom PH. Environ Toxicol Chem 1996;15:1388

Organohalogen Compounds Vol 68 (2006) 1946