Date of Original Version
The Antarctic continent is among the most pristine regions; yet various organic contaminants have been measured there routinely. Air and snow samples were collected during the austral spring (October - November, 2010) along the western Antarctic Peninsula and analyzed for organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) to assess the relative importance of long-range transport versus local primary or secondary emissions. Highest concentrations of PCBs, PBDEs and DDTs were observed in the glacier's snow sample, highlighting the importance of melting glaciers as a possible secondary source of legacy pollutants to the Antarctic. In the atmosphere, contaminants were mainly found in the vapor phase (> 65 %). Hexachlorobenzene (33.6 pg/m3), PCBs (11.6 pg/m3), heptachlor (5.64 pg/m3), PBDEs (4.22 pg/m3) and cis-chlordane (2.43 pg/m3) were the most abundant contaminants. In contrast to other compounds, PBDEs seem to have originated from local sources, possibly the research station itself. Gas-particle partitioning for analytes were better predicted using the adsorption partitioning model than an octanol-based absorption approach. Diffusive flux calculations indicated that net deposition is the dominant pathway for PBDEs and chlordanes, whereas re-volatilization from snow (during melting or metamorphosis) was observed for PCBs and some OCPs.
Khairy, M. A., Luek, J., Dickhut, R., & Lohmann, R. (2016). Levels, Sources and Chemical Fate of Persistent Organic Pollutants in the Atmosphere and Snow along the Western Antarctic Peninsula. Environmental Pollution, 216, 304-313.
Available at: http://dx.doi.org.10.1016/j.envpol.2016.05.092