- GeoRef, Copyright 2008, American Geological Institute.
Accidents and spillages are an inevitable consequence of the worldwide transport of crude oil and refined petroleum products by sea. The number of major spills occurring each year has decreased since the 1970s, but spillages and operational discharges from tankers nonetheless constitute a significant input of oil to the marine environment. The rapid uptake of oil and polycyclic aromatic hydrocarbons (PAHs) by exposed fish and shellfish, resulting from large oil spillages in coastal waters, poses a potential threat to human consumers of fish and shellfish and also affects the marketability of catches. In this article, the processes influencing uptake and retention of PAHs in fish and shellfish are outlined by drawing on the experience gained from previous incidents. This includes particular reference to three recent major oil spills from tankers in the United Kingdom and the United States, those involving the Exxon Valdez, Braer, and Sea Empress, and to the resulting contamination of local stocks. A more uniform approach to oil spill monitoring would aid comparisons between spills and would help interpret the kinetics and dynamics of released hydrocarbons in future cases. Currently, no statutory limits or guideline values have been established for PAHs in edible tissues of fish or shellfish, whether derived from oil or combustion sources.