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Kuwait's northern marine area is considered to be the receiving basin for the influx of sediments and associated pollutants from the Shatt Al-Arb estuary. In recent years, Iraq has undertaken to drain the southern marshes, which acted as a sink for the associated pollutants. This loss of marshes is expected to have far reaching consequences on the ecology of the northern Gulf. Bottom sediments from the area likely to be impacted by the draining of the marshes were studied for a variety of parameters. The results showed that petroleum-related pollutants (Ni, V, TPH, PAH and n-alkanes) were, generally, much higher in the southern part of the study area which may be due to the tanker traffic. Spotty higher levels of petroleum were encountered in the northern area, which were of recent origin and may have been the result of the draining of marshes. Chlorinated pesticides and PCBs were not detected in any of the samples. In general, there were indications of the negative impact of the draining of the marshes, however, long-term and more detailed studies are needed.

The chemical speciation of trace metals (Cd, Co, Cr, Cu, Ni, Pb and Zn) in marine sediments from Sulaibikhat Bay, Kuwait was determined using a three-step sequential extraction procedure. To obtain a mass balance, a fourth step, i.e. digestion and analysis of the residue was undertaken using a microwave-assisted acid digestion procedure. The sum of the 4 steps (acid-soluble + reducible + oxidizable + residual) was in good agreement with the total content (71–116%), suggesting that the microwave extraction procedure is efficient. The results showed that all metals except for Pb and Zn were present at higher percentages in the residual fraction. The reducible fraction was the next followed by the oxidizable fraction. The exchangeable fraction was least important as a host for most metals. The mobility order of exchangeable fraction of the elements in surface sediments decreased in the order Cd > Zn > Cu > Co > Pb > Ni > Cr; the reducible fraction in the order Pb > Zn > Cu > Cd > Co > Ni > Cr; the oxidizable fraction in the order Pb > Cu > Cd > Ni > Co > Zn > Cr, and the residual fraction in the order Cr > Ni > Co > Cu > Cd > Zn > Pb. The data showed that the speciation of trace elements in sediments close to a sewage outfall was different from that of sediment from other parts of Sulaibikhat Bay. This suggests that the contribution of the sewage outfall to metal pollution in adjacent marine area is positive and is associated with fine-grained sediments with high level of organic content, which are major controlling factors for the distribution of trace metals in this part of the Bay.