Petroleum hydrocarbons in oysters from Galveston Bay

Oysters from a location in Galveston Bay, Texas, were analyzed for petroleum-derived hydrocarbons. The lipids and hydrocarbons were Soxhlet - extracted with benzene/methanol and then partitioned into n-pentane. Hydrocarbons were separated from the lipids by column chromatography on a bed of silica gel covered by alumina; both absorbents were deactivated to prevent the formation of artifacts from sensitive components of the lipid fraction. Preparative TLC on activated silica gel then resolved the column effluent into aliphatic, mono-, di-, and tri-aromatic hydrocarbons. Individual compounds and compound types were identified from their gas chromatographic retention indices, mass spectra, and UV spectra. The severe oil contamination of the oysters is evident: the concentration distribution of the aliphatic hydrocarbons is similar to the distribution found in a crude oil and alicyclic and aromatic hydrocarbons are encountered at higher concentrations than in uncontaminated oysters.