Molecular and Stable Carbon Isotopic Characterisation of PAH Contaminant at Mc Murdo Station, Anatrctica

In this study were analyzed samples from McMurdo Station for PAH molecular and stable carbon isotopic compositions to discern the origins of contaminants in the area. Total PAH concentrations ranged from 664 ng g-1 to 74,267 ng g-1 dry wt for soil samples Elevated PAH contamination on land was found in areas where fuels were stored and in areas of parking and heavy traffic in central McMurdo Station. The mean total PAH concentrations in the samples from the four sites of known contamination sources on land (the fuelling stations, the old oil tanks, the helipad and the machine shop) differed by about a factor of two from 17,567 ng g-1 in 1999 to 38,326 ng g-1 in 2001. The large changes in PAH concentrations observed at the fuelling stations and the machine shop are presumably due to on-going contamination. At the sites of old oil storage tanks and the helipad, statistically significant changes in total PAH concentrations between the two different samplings were not observed. On-going introduction of fuel PAHs at the fuelling station and the machine shop were confirmed by the ‘‘freshness’’ of the spills as indicated by the alkylnaphthalenes to total PAH ratios