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.
Negoita
Teodor G
TG
Romanian Polar Research Institute, C.P. 42-29, Sector 4, Bucharest, Romania.
Covaci
Adrian
A
Gheorghe
Adriana
A
Schepens
P
P
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