Microtox assay for assessment of marine pollution in industrial discharge zone of Kuwait

Twelve major industries in the Shuaiba Industrial Area of Kuwait generate about 30,000 m(3)/d wastewater, which is discharged to the sea either directly or after treatment. To assess the quality of the Shuaiba bay area, water samples were collected twice a week for six months from seven points of discharge, each representing a source from a major industry. Samples were analyzed for physicochemical characteristics and toxicity using the Microtox assay. Chemical analysis revealed that the contamination of oil was higher at sites 5 and 6 while four heavy metals were evenly distributed at different sites. The Microtox assay indicated that 31 samples out of 378 samples exerted acute to medium levels of toxicity, which were mostly from sites 6 and 7. The episodes of toxicity were greater in the summer months compared to winter months, whereas the pattern of chemical contaminants was not influenced by the seasonal change. (C) 1997 by John Wiley & Sons, Inc.