Persistent Organic Pollutants (POPs) in Fish Consumed by the Indigenous Peoples from Nenets Autonomous Okrug

Currently, monitoring of persistent organic pollutant (POP) content in various biological and environmental matrixes in the Arctic is an urgent task. The present study focused on the determination of POPs such as: PCB#28, PCB#52, PCB#101, PCB#105, PCB#118, PCB#123, PCB#153, PCB#128, p,p'-DDE, o,p'-DDE, p,p'-DDD, o,p'-DDD, hexachlorobenzene (HCB), cis-nonachlor, trans-nonachlor, cis-chlordane, trans-chlordane, mirex, 1,2,3,5-tetrachlorobenzene and 1,2,4,5-tetrachlorobenzene in fish consumed by the indigenous people of the Nenets Autonomous Okrug (NAO) of the Russian Arctic. Fish samples were analyzed by gas chromatography triple quadrupole mass spectrometry (GC-MS/MS) using the multiple reaction monitoring (MRM) technique. The obtained results show that the major POPs in fish were dichlorodiphenyltrichloroethane (DDT) breakdown products and polychlorinated biphenyls (PCB) congeners. The n-ary sumation PCB8 in pink salmon, Arctic char, navaga, humpback whitefish and northern pike were 1.54, 1.58, 1.24, 0.72 and 0.32 ng/g (ww), respectively. The main PCB congeners maximum average medium concentrations were 0.68 ng/g (ww) and 0.51 ng/g (ww) of PCB#153 in navaga and PCB#128 in pink salmon, respectively. The main DDT breakdown product was p,p'-DDE. In Arctic char, pink salmon, navaga, humpback whitefish and northern pike, the concentration of p,p'-DDE was 0.58, 1.61, 0.49, 0.63 and 0.08 ng/g (ww), respectively. A moderate positive relationship between n-ary sumation PCB8 and lipid content and a high positive relationship between n-ary sumation DDT and lipid content were observed. In fish samples with fat content <0.5% (northern pike, humpback whitefish), the amount of analyzed POPs was 2 or more times lower than that in fish species with fat content >1% (pink salmon, Arctic char). Despite the large number of fish in the diet of indigenous peoples from NAO, no significant risks were identified. Most legacy POP and organochlorine pesticides (OCPs) tend to decrease, which can be explained by past national and regional bans and restriction on their use and emission.