Persistent organic pollutants in migratory birds from wetlands of southern Primorye, Russia

The study focuses on the accumulation and biotransformation of persistent organic pollutants (POPs), including organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs), in the organs of migratory birds from the family Anatidae inhabiting southern Primorye, Russia. Feathers, liver, and breast muscle samples for the analysis were collected from 26 individuals of six anatid species in Lake Khanka and the Peschany Peninsula. The total POP content in feathers ranged from 0.4 to 44.5 ng/g dry weight (dw); in muscles, from 9.0 to 282.4 ng/g lipid weight (lw); and in the liver, from 12.1 to 1117.1 ng/g lw. In general, POP concentrations did not differ significantly (p > 0.05). The predominance of DDT metabolites (p,p'-DDE) and HCH isomers (β- and δ-HCH) indicated the long-term circulation of these substances in the ecosystem. PCBs were represented by both lower (28) and higher chlorinated congeners (118, 153, 138, and 180), with the latter accumulated mainly in species that come in contact with bottom sediments, i.e., diving ducks (Greater Scaup and Tufted Duck). The observed differences between the species in POP accumulation are associated with their ecological characteristics including diet, migration routes, and habitats. The results show that the pollution levels in southern Primorye are lower or comparable to those reported for other Asian regions, but the global background of pesticides still continues to have an impact on ecosystems.