Organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in Pacific salmon from the Kamchatka Peninsula and Sakhalin Island, Northwest Pacific.

The purpose of the present study was to determine levels of POPs (dieldrin, endrin, HCH isomers, DDT metabolites, and PCB congeners) in organs of chum (Oncorhynchus keta), pink (O. gorbuscha), sockeye (O. nerka), masu (O. masou), and Chinook salmon (O. tshawytscha), and to identify the patterns of toxicants' distribution in organisms and the environment of the northwestern Pacific. Principal component factor analysis showed that all the salmon species typically exhibit relationships between the PCB congeners and are characterized by a similar pattern of entry of PCBs 101, 118, and 153. The OCPs levels in the organs of Pacific salmon are decreasing from 2012 to 2018, which suggests the elimination of these toxicants from the northwestern Pacific Ocean.

Flounders as indicators of environmental contamination by persistent organic pollutants and health risk.

The purpose of this study was to elucidate the potential of using flounders as bioindicators of accumulation and transformation of POPs and to assess the possible environmental risk to the health of the population of the Russian coastal regions. The mean levels of HCH, DDT, and PCBs in the flounders were as follows: in the eastern Sea of Okhotsk, 49 ± 51, 62 ± 89, and 106 ± 83 ng/g lipid weight; in the southern Sea of Okhotsk, 36 ± 37, 15 ± 16, and 97 ± 41 ng/g lipid wt; in the Sea of Japan/East Sea, 62 ± 36, 39 ± 28, and 1616 ± 1177 ng/g lipid wt, respectively. In the Tatar Strait, OCPs were represented mainly by ß-HCH with a concentration of 221 ± 182 ng/g lipid wt; the PCB level was 455 ± 317 ng/g lipid wt. Values of ILCR = 2.1·10-5 due to the consumption of flounder from the Sea of Japan/East Sea at a rate of 29 kg/yr indicate a probability of developing cancer during a lifetime.

Organochlorine pesticides (HCH and DDT) in blubber of spotted seals (Phoca largha) from the western Sea of Japan.

In 2014-2019, a total of 31 blubber samples were collected from spotted seals (Phoca largha) in the western Sea of Japan. The samples were analyzed by gas chromatography to determine level of organochlorine pesticides (OCPs). The concentration of hexachlorocyclohexane and its isomers (∑HCH) ranged from 389 to 50,070 ng/g lipid weght; the concentration of dichlorodiphenyltrichloroethane and its metabolites (∑DDT), ranged from 62,720 to 1,110,930 ng/g lipid wt. Transfer of HCH and DDT from mother to pup during pregnancy and lactation was documented. The OCP concentration in blubber of spotted seals from the western Sea of Japan is one to two orders of magnitude higher than in spotted seals inhabiting waters off the Japan coast. Organochlorines detected in the western Sea of Japan likely come from some countries of Southeast Asia still using OCPs in the agriculture sector.

Organochlorine pesticides and polychlorinated biphenyls in the Bering flounder (Hippoglossoides robustus) from the Sea of Okhotsk.

The purpose of this study is to establish the presence of POPs in the Bering flounder (Hippoglossoides robustus) from the Sea of Okhotsk (North-West Pacific). Concentration of OCPs (α-HCH, ß-HCH, γ-HCH, o,p'-DDT, p,p'-DDT, o,p'-DDD, p,p'-DDD, o,p'-DDE and p,p'-DDE) and PCBs (28, 52, 155, 101, 118, 143, 153, 138, 180, 207) in samples were measured by GC-MS and GC-ECD. The mean OCP concentrations in flounder from East and South areas of the Sea of Okhotsk were 99.8 ±â€¯125.4 and 53.6 ±â€¯40.5 ng/g lipid, respectively; PCB congeners - 112 ±â€¯94.2 and 88.8 ±â€¯50.8 ng/g lipid, respectively. POPs in fish tissue decreased in the order: PCBs > HCHs > DDTs. Our results indicate that consumers will have no health risk due to fish consumption from Sea of Okhotsk. OCP and PCB levels in the Sea of Okhotsk may be considered as background level for the North Pacific.

Bioindicators of Organochlorine Pesticides in the Sea of Okhotsk and the Western Bering Sea.

Organochlorine pesticides (OCPs), such as HCHs and DDTs, are still used as pesticides in the Southern Hemisphere and can reach the North Pacific due to long range atmospheric transfer. Marine mammals (Pacific walrus Odobenus rosmarus divergens, gray whale Eschrichtius robustus), the seabirds (Pacific gull Larus schistisagus, crested auklet Aethia cristatella, auklet crumb Aethia pusilla, northern fulmar Fulmarus glacialis, and grey petrel Oceanodroma furcata) and Pacific salmon (pink Oncorhynchus gorbuscha, chum O. keta, chinook O. tshawytscha, and sockeye O. nerka) were collected near the Kuril Islands (the northern-western part of the Pacific Ocean), in the Sea of Okhotsk and the Bering Sea. The total OCPs concentration (HCHs + DDTs) was found in each organism, including the Pacific walrus (70-90,263 ng/g lipid), the seabirds (29-16,095 ng/g lipid), and the Pacific salmon (41-7103 ng/g lipid). The concentrations and possible sources of OCPs in marine organisms as biological indicators are discussed.

Bioaccumulation of organochlorine pesticides (OCPs) in the northern fulmar (Fulmarus glacialis) from the Sea of Okhotsk.

Hexachlorocyclohexane (HCH) isomers (α-, ß-, and γ-), DDT and its metabolites (DDD and DDE) were detected in five individuals of Northern fulmar Fulmarus glacialis Linnaeus, 1761 from the Sea of Okhotsk. The average amount of HCHs in the organs of fulmars ranged from 608±177ng/g lipids in the total homogenate of the organs to 2093±264ng/g lipids in the feathers with skin. The average range of the amounts of DDTs was from 3606±333ng/g lipids in the feathers with skin to 4076±1624ng/g lipids in the feathers. The bioaccumulation of DDTs by seabirds of the Sea of Okhotsk is approximately equal to that of birds from other regions of the world's oceans, while the HCHs concentration is significantly higher.

Bioaccumulation of persistent organochlorine pesticides (OCPs) by gray whale and Pacific walrus from the western part of the Bering Sea.

The feeding habits of a gray whale (Eschrichtius robustus) and a Pacific walrus (Odobenus rosmarus divergens), caught from the western Bering Sea in the summers of 2010 and 2011, have been studied, and concentration of persistent organochlorine pesticides (OCPs) in their organs determined. The total OCP concentration (∑HCH+∑DDT) in muscles and liver of the gray whales varies from 297 to 3581 and from 769 to 13,808 ng/g lipids, respectively. The total OCP concentration (∑HCH+∑DDT) in muscles and liver of the Pacific walruses varies from 197 to 5659 and from 4856 to 90,263 ng/g lipids, respectively. The specifics of diet as a source of pesticide accumulation in these two marine mammal species are discussed.