Petroleum hydrocarbons in oysters from Galveston Bay

Oysters from a location in Galveston Bay, Texas, were analysed 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 silicagel covered by alumina; both absorbents were deactivated to prevent the formation of artifacts from sensitive components of the lipid fraction. Preparative TLC on activated silicagel 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: (1) The concentration distribution of the aliphatic hydrocarbons is similar to the distribution found in a crude oil. (2) Alicyclic and aromatic hydrocarbons are encountered at higher concentrations than in uncontaminated oysters