Oil spill identification

To unambiguously identify spilled oils and petroleum products and to link them to the known sources are extremely important in settling questions of environmental impact and legal liability. This article briefly reviews the most recent development and advances of chemical fingerprinting and data interpretation techniques which are most frequently used in oil spill identification studies, including recognition of relative distribution patterns of petroleum hydrocarbons, analysis of 'source-specific marker' compounds, determination of diagnostic ratios of specific oil constituents, isotopic analysis, and several other emerging techniques. The issue of how biogenic and pyrogenic hydrocarbons are distinguished from petrogenic hydrocarbons is also addressed. Finally, the example of the Exxon Valdez spill is reviewed to illustrate how complex hydrocarbon mixtures were identified and allocated to multiple sources by using these advanced chemical fingerprinting techniques. (C) 1999 Elsevier Science B.V. All rights reserved.