Distribution of polychlorinated biphenyls (PCBs) and organochlorine pesticides in soils from the East Antarctic coast.
Concentrations of hexachlorobenzene (HCB), alpha-, beta- and gamma-hexachlorocyclohexane (HCH) isomers, 6 o,p'-and p,p'-isomers of DDT and 28 PCB congeners have been measured in eleven soil samples and one lichen collected on the Eastern coast of Antarctica from 5 Russian stations. For samples with low concentrations of PCBs (range 0.20-0.41 ng g(-1) dry weight) and pesticides (0.86-4.69 ng g(-1) and 0.11-1.22 ng g(-1) dry weight for HCHs and DDTs, respectively), atmospheric long-range transport from Africa, South America or Australia was suggested as the sole source of contamination. The profile of PCB congeners was dominated by the more volatile tri-, tetra- and penta-PCBs congeners, thus supporting long-range transport hypothesis. Four samples contained moderate levels of PCBs (range 1.98-6.94 ng g(-1) dry weight) and variable concentrations of pesticides (gamma-HCH, p,p'-DDT and o,p'-DDT being the main contaminants). For samples with high concentrations of PCBs (range 90.26-157.45 ng g(-1)) and high concentrations of pesticides, the presence of high molecular weight PCB congeners such as: 153, 180, 187, 170 etc, strongly suggest a local source (biotic) of PCBs rather than atmospheric transport. It is likely that on a local scale, biotic focussing of pollutants, due to bird activities (nesting and excrement) can cause high contamination levels and become more significant than contaminant input via abiotic pathways.
Romanian Polar Research Institute, C.P. 42-29, Sector 4, Bucharest, Romania.
Teodor G
TG
Negoita
Adrian
A
Covaci
Adriana
A
Gheorghe
P
P
Schepens
D000392:Air Movements; D000864:Antarctic Regions; D004784:Environmental Monitoring; D004785:Environmental Pollutants / Q000032:analysis*; D007306:Insecticides / Q000032:analysis*; D008011:Lichens / Q000737:chemistry; D011078:Polychlorinated Biphenyls / Q000032:analysis*; D012426:Russia; D012989:Soil Pollutants / Q000032:analysis*
D004785:Environmental Pollutants; D007306:Insecticides; D012989:Soil Pollutants; D011078:Polychlorinated Biphenyls