Antarctic: Persistent Organic Pollutants and Environmental Health in the Region

Antarctica is considered of crucial importance for the ecological equilibrium of the Earth, the global climate, the freshwater mass balance, the global ecosystem equilibrium including human health. The Antarctic ecosystems are very fragile and show low resilience capacity; small environmental alterations can cause dramatic consequences, often irreversible, that may impact the Earth equilibrium. The knowledge of levels and patterns of contaminants is necessary to understand the risk for organisms, including humans, and it is very important for evaluating the global environmental health and other possible consequences at a global scale. Persistent organic pollutants (POPs) and new contaminants (e.g., novel flame retardants, plastics including micro- and nano-plastics) can be found in Antarctica and in the Southern Ocean, despite their remoteness and geographical isolation. In this regions of the Earth, the extreme weather conditions largely affect the ecosystem structure and functioning. Moreover, the global change may affect contaminant dispersion and distribution in ecosystems by increasing their mobilization, the ice melting, and the following release of contaminants trapped in it, letting them becoming available again for bioaccumulation. The increasing tourism in the region can be a further pollution source. This article aims to provide background information on levels and patterns of contaminants in the Antarctic ecosystems, including comparisons among areas and species, and temporal trends. The POPs under considerations were pesticides [e.g., aldrin, chlordanes, dichloro diphenyl trichloroethane (DDT), dieldrin, endrin, HCB, mirex, heptachlor, toxaphenes], industrial chemicals (PCBs, PBDEs), and by-products [polychlorinated-dioxins (PCDDs), polychlorinated-furans (PCDFs)]. Furthermore, the concentration of the 2,3,7,8-tetrachlorodibenzo-p-dioxin toxic equivalents (TEQs) was also reported, when available, to estimate the risk for organisms.