PETROLEUM-HYDROCARBONS AND TRACE-METALS IN NEARSHORE GULF SEDIMENTS AND BIOTA BEFORE AND AFTER THE 1991 WAR - AN ASSESSMENT OF TEMPORAL ANDSPATIAL TRENDS

Immediately following the 1991 Gulf War, a survey was organized to det ermine the extent and degree of contamination by petroleum hydrocarbon s and trace metals that entered the Gulf from the massive oil spill an d oil field fires in Kuwait. Between June-October 1991 samples of near shore sediments, bivalves and fish were collected from Kuwait, Saudi A rabia, Bahrain, UAE and Oman. Analyses revealed that the highest level s of contamination were along the heavily-impacted coast of Saudi Arab ia between Ras Al Khafji and Ras Al Ghar, where concentrations of tota l petroleum hydrocarbons (expressed as Kuwait crude oil equivalents) r anged from 62-1400 mug g-1 dry wt in surface sediments, 570-2600 mug g -1 dry wt in clams and 9.6-31 mug g-1 dry wt in fish muscle. Gas chrom atographic analyses indicated that much of the oil in the intertidal z one had substantially degraded within a few months of the spill. Conce ntrations of the oil-related metals Ni and V were slightly elevated in oil-contaminated sediments from Saudi Arabia but elsewhere in the Gul f were similar to levels measured in earlier years at those sites. Thi s initial regional survey demonstrated that hydrocarbon contamination originating from the war-related pollution events was restricted to ap proximately 400 km from the source, that levels of combustion derived PAHs in the marine environment at that time (e.g. 1-450 ng g-1 dry wt for pyrene in sediments) were of the same order as those which have be en measured in several coastal areas of the eastern United States and northern Europe, and that outside the immediate area of impact, petrol eum hydrocarbon and trace metal levels in sediment and bivalves were g enerally as low as, or lower than, those concentrations measured at th e same sites before the war.