Concentrations of such persistent organic pollutants (POPs) as polychlorinated biphenyls (PCBs) are high in certain Arctic animal species. The polar bear, Arctic fox, and glaucous gull may be exposed to PCB levels above lowest-observed-adverse-effect-level (LOAEL) values for adverse effects on reproduction in mammals and birds. However, the dioxin-like congeners seem to be major contributors to the reproductive effects of PCBs and the relative concentrations of these congeners are low in polar bears. Temporal trends for POPs in Arctic wildlife and the sensitivities of Arctic species to these compounds determine the risk for future adverse health effects.