Occurrence of Petroleum Hydrocarbons in Some Australian Seabirds.

The hydrocarbons occurring in four common species of seabird from the Brisbane River estuary area were isolated and examined by gas chromatography. By examination of the patterns of occurrence of the hydrocarbons and by identification of hydrocarbons of recent biogenic origin it was possible to determine the hydrocarbons of petroleum origin (up to 1038 pg g-I in muscle tissue). The evidence indicates that these hydrocarbons have originated from low concentrations of similar petroleum substances in the Brisbane River estuary, a proportion having been transferred to the birds from food organisms, although other mechanisms are possible. The results show that the n-alkanes are degraded or excreted in preference to the branched and cyclic alkanes, either within the birds or before absorption.