The ETOX unit is mainly developing research in the domains of ecotoxicology of polar marine ecosystems (Antarctica, Greenland Sea, Barents Sea), mainly for the higher trophic levels (seabirds, marine mammals). The concentration, transfer, accumulation and detoxification mechanisms of stable pollutants (organochlorine pesticides, total and organic mercury) are investigated. The ecotoxicology of terrestrial ecosystems is also studied (stable pollutants in raptors and owls and their prey, etc.). Research also concerns marine ecology, namely the quantitative distribution of seabirds and marine mammals at sea, mainly in the NE Atlantic and polar ecosystems: European Arctic, Antarctica.