ISSN 0012�4966, Doklady Biological Sciences, 2014, Vol. 456, pp. 188–190. © Pleiades Publishing, Ltd., 2014.Original Russian Text © O.N. Lukyanova, V.Yu. Tsygankov, M.D. Boyarova, N.K. Khristoforova, 2014, published in Doklady Akademii Nauk, 2014, Vol. 456, No. 3, pp. 363–365.

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Persistent organic pollutants (POPs) are toxicxenobiotics that circulate in the biosphere overdecades. At present, the global background of POPshas been formed on the planet. The pollutants aretransported by wind from the regions of their use(tropical and subtropical latitudes) over long distancesto middle and polar latitudes. During the last third ofthe 20th century, hexachlorocyclohexane (HCH) anddichlorodiphenyltrichloroethane (DDT) have beenthe most actively used among organochlorine pesti�cides OCPs. Along with the atmospheric transport,POPs are dispersed in the world ocean by marineorganisms that migrate over long distances. Primarily,the biotransport of POPs is performed by salmon, theamount of which has increased recently and is now1.0–1.5 million tons in the subarctic region of thePacific Ocean [1]. Along with biogenic elements,salmon, which die after spawning in rivers and lakes,contaminate their habitats with pollutants accumu�lated during their feeding and growing period in theocean; the amount of pollutants may be high. The aimof our study was to estimate the role of Pacific salmonin global transport of OCPs during their biotransportfrom the open ocean to the Russian coast of the FarEastern seas.

Salmon (6 specimens of pink salmon Oncorhynchusgorbusha and 6 specimens of chum salmon O. keta)were caught in marine cruise of the Pacific FisheriesResearch Center (Vladivostok, Russia) in the region ofthe Kuril Islands in the Pacific Ocean in June–July2013. Frozen samples (–20°C) were transported to lab�oratory. Before the analysis, whole specimens of pinksalmon and chum salmon were homogenized. Afterextraction into organic solvents, the concentrations ofα�, β�, and γ�hexachlorocyclohexane (HCH), DDT,

dichlorodiphenyldichloromethylmethane (DDD)and dichlorodiphenyldichloroethylene (DDE) weredetermined by the method of gas chromatography [2].Chlororganic pesticides were detected in all samples ofPacific salmon under study. The total concentration ofOCPs as the sum HCH + DDT in chum salmon wassignificantly higher than in pink salmon (Table 1),which may be the result of different fat content in fishand duration of their stay in sea. After downstreammigration of juveniles to the sea, pink salmon returnsto spawn in freshwaters in a year, whereas chumsalmon may spend two to five years in the sea andaccumulate different pollutants in organs.

The total concentration of HCH isomers washigher than DDT in all samples. It is known that somepesticides evaporate in tropical and subtropical lati�tudes, are transported by wind and deposited at higherlatitudes. Because of the high volatility of HCH, itsconcentrations in salt water of the Pacific Oceanincreases when moving from subtropics northwards.DDT is less volatile, and its high concentrations aredetected in the sites of its use [3, 4]. In salmon, α andβ isomers prevail over HCH isomers and DDE prevailover DDT metabolites, which testifies to decay of ini�tial compounds, i.e., of “prolonged” contaminationand circulation of pesticides in the environment.

The number of salmon migrating to the Russiancoast varies from year to year, but the structure of

Pesticide Biotransport by Pacific Salmonin the Northwestern Pacific Ocean

O. N. Lukyanovaa, b, V. Yu. Tsygankovb, M. D. Boyarovab, and N. K. Khristoforovab

Presented by Academician A.V. Andrianov November 25, 2013

Received January 23, 2014

DOI: 10.1134/S0012496614030089

a Pacific Fisheries Research Center (TINRO�Center), Vladivostok, 690950 Russiab Far Eastern Federal University, Vladivostok, 690091 Russiae�mail: olgaluk@gmail.com; olga.lukyanova@tinro�center.ru

GENERAL BIOLOGY

Table 1. Average values of the total concentration (ng/g wetweight) of HCH isomers (α�HCH + β�HCH + γ�HCH)and DDT and metabolites (DDT + DDD + DDE) in Pa�cific salmon bodies; M ± m, n = 6

Species HCH DDT + DDD + DDE COPs

Pink salmonO. gorbusha

58.7 ± 12.4 10.2 ± 2.1 68.85 ± 14.55

Chum salmonO. keta

167.5 ± 51.1 15.0 ± 11.8 182.5 ± 60.2

DOKLADY BIOLOGICAL SCIENCES Vol. 456 2014

PESTICIDE BIOTRANSPORT BY PACIFIC SALMON 189

migratory fish remains the same: pink salmon consti�tute 60–65%, chum salmon constitute 20–25%, andredfish constitute 10–12%. The proportion of silversalmon and Chinook salmon is small. Chum salmonand pink salmon are the main migratory fish in theeastern part of Kamchatka, eastern Island, the conti�nental coast of the Sea of Okhotsk, and in the AmurRiver basin. The maximum catches of salmon(542 000 t) were recorded in 2009. The number of fishthat performed spawning migrations to some regionsof the Far East in 2009 [5] is shown in Table 2. Theaverage mass of one specimen of pink salmon is 1.3 kg,and the average mass of one specimen of spawningchum salmon is 3.5 kg. Our calculations show that onespecimen of pink salmon contains as much as 90 µg ofpesticides, and one specimen of chum salmon, asmuch as 640 µg of pesticides.

The amount of OCPs transported by these salmonspecies to eastern Kamchatka is 10.4 kg; to the AmurRiver basin, more than 13 kg; to the continental coastof the Sea of Okhotsk, 5.6 kg; and the total amount ofOCPs transported to the Pacific coast of Russia ismore than 30 kg. The amount of pesticides varies fromyear to year, but the total concentration of pesticides ina particular habitat increases. These compounds arerather persistent and can circulate in the ecosystem fora long time. They may enter the food web and affectthe terrestrial organisms of a higher trophic level [6, 7],primarily, predators. According to expert evaluation,the catches of salmon by brown bear and sea mammalsamount from 50 000 to 100 000 t, which is rather muchcompared to commercial catches in the past years(300 000–540 000 t) [1]. It is assumed that bears con�sume from 10 000 to 30 000 t of salmon; i.e., theytransfer from 1.5 to 4 kg of pesticides to the Pacificcoast of Russia.

The biotransport of OCPs to spawning groundsdepends on the number of migrating spawners,whereas the input of toxicants to the human body withconsumed salmon is determined by the amount of

caught fish. In recent years, the catches of salmon inRussian waters are high: 542 000 t in 2009, 325 000 t in2010, 504 000 t in 2011, 438 000 t in 2012, and about400 000 t in 2013. The amount of pesticides in salmonthat are caught during a year is from 40 to 67 kg.Finally, the pesticides are spread on land. According tosome evaluations, the transfer of pollutants to coastalecosystems by salmon two to six times exceeds theatmospheric transfer [8, 9].

Now, salmon as a mass fish in the upper layer ofepipelagial of the northern Pacific Ocean dominate atdepths from 0 to 50 m [1]. Precisely in this layer, atmo�spheric precipitations, pollutants deposited on sus�pended particles, and toxic products of decomposedplastic may concentrate and be accumulated bysalmon [10].

In the past years, the pollution of coastal waterswith pesticides has decreased as a result of measures onprohibition of their use. However, in the open ocean,water pollution by contaminants is still rather high.The ocean is a reservoir that receives persistent toxi�cants, and bioaccumulation of pesticides in the oceancontinues in food chains. Salmon provide biotransportof POPs in the biosphere and their global transportfrom sea to land.

ACKNOWLEDGMENTS

This study was partly supported by the program“Scientific Foundation” of the Far Eastern FederalUniversity, project no. 12�04�13000�33/13.

REFERENCES

1. Shuntov, V.P. and Temnykh, O.S., Tikhookeanskielososi v morskikh i okeanicheskikh ekosistemakh (PacificSalmon in Marine and Ocean Ecosystems), Vladivos�tok: TINRO�Tsentr, 2011, vol. 2.

Table 2. Escapement of Pacific salmon (thousand specimens) to spawning areas [5] and the amount of OCPs (g) transport�ed by fish to the Pacific coast of Russia in 2009

Region Pink salmon Amount of OCPs Chum salmon Amount of COPs Total of OCPs

Western Bering Sea 170 15.2 1943 120 1215

Eastern Kamchatka 94497 8500 2954 1900 10400

Western Kamchatka 3 0.2 716 457 457

Continental coast of the Sea of Okhotsk

67 6.0 8828 5600 5606

Southern Kuril Islands 7 0.6 73 46 47

Eastern Island 18479 1600 513 327 1927

Amur River basin 2927 262 20079 12800 13062

Total 116147 10384 26278 21250 31634

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2. Klisenko, M.A., Mel’tser, F.R., Novikova, K.F., et al.,Assays for Microscopic Amounts of Pesticides in Foods,Forage, and Environment, Moscow: Kolos, 1983.

3. Wania, F., Mackay, D., Environ. Sci. Technol., 1996,vol. 30, pp. 390A–396A.

4. Tanabe, S., Dev. Environ. Sci., 2007, vol. 7, pp. 773–817.

5. www.npafc.org.

6. O’Toole, S., Metcalfe, C., Craine, I., and Gross, M.,Environm. Pollut., 2006, vol. 140, pp. 102–113.

7. Veldhoen, N., Ikonomou, M., Dubetz, C., et al., Aquat.Toxicol., 2010, vol. 97, pp. 212–225.

8. Ewald, G., Larsson, P., Linge, H., et al., Arctic, 1998,vol. 51, no. 1, pp. 40–47.

9. Krummel, E.M., Macdonald, R.W., Kimpe, L.E.,et al., Nature, 2003, vol. 425, pp. 255–256.

10. Choy, C.A. and Drazen, J.C., Mar. Ecol.: Proc. Ser.,2013, vol. 485, pp. 155–163.

Translated by N. Ruban