Analysis of Petroleum Type Hydrocarbons in Marine Samples Using Gas Chromatography and Mass Spectrometry

The indigenous hydrocarbons in samples of zooplankton, shrimp (Penaeus aztecus) and sediment are extracted by refluxing with a series of organic solvents fractionated by column chromatography and then resolved by high resolution gas chromatography. The above fractions were then spiked with the aliphatic or aromatic components isolated from a Louisiana crude oil and rechromatographed. Identification of resolved hydrocarbons is achieved by use of a gas chromatograph-mass spectrometer combination. Capillary columns enable almost complete resolution of all the isoprenoid, branched and cyclic alkanes that are important in determining the presence of petroleum in a marine sample. Many of the key petroleum aromatic compounds could also be resolved by use of capillary columns from many of the naturally occurring esters, alkenes and related organics. The greater the reliance on gas chromatography as the principle tool to establish the presence of trace petroleum pollution in marine samples, the greater the need to employ high resolution chromatography.