PBDEs and PCBs in terrestrial ecosystems of the Victoria Land, Antarctica

The Victoria Land (East Antarctica) is characterized by the presence of lakes and ponds where rare water is found during the Summer months. These freshwater ecosystems are an important resource for migrating seabirds that use them and leave there their droppings and feathers, contributing to enrich the water with organic matter. Persistent organic pollutants (POPs) are long-range transported to polar regions and their detection in the Antarctic ecosystems date back to the 1960s. Most studies have been related to POP concentrations in marine environment, and terrestrial ecosystems have been poorly investigated. This study reports the concentration of PBDEs (23 congeners) and PCBs (21 among non-, mono-, di-, and ortho congeners) in lake sediment, soil and vegetation mat (community of algae, cyanobacteria, bryophites) collected close to six lakes in the Victoria Land (74°31'S-74°97'S, 165°07'E-162°51'E): Edmonson Point 14 and 15A, Carezza, Enigma, Tarn Flat 20, Inexpressible Island 10B. The ∑PBDEs averaged 0.09-0.28 ng/g and BDEs 28, 47 and 154 were higher in mat and soils, while BDEs 183 and 47 in sediment samples. PCBs ranged <0.003-0.807 ng/g and congeners nos. 114, 138, and 187 were the most abundant. In addition, TEQs were derived for the non-and mono-ortho PCBs detected and values were very low in each matrix (0.010 pg/g in the soil, 0.012 pg/g in sediment and mat). The long-range atmospheric transport can be confirmed as the most important POP source in Antarctica, although the scientific stations and seabird colonies may be potential local sources and contribute to contaminant release.