The water quality of Izmir bay: a case study.

About 30 studies from the published literature were reviewed to determine the status of several categories of pollutants (i.e., nutrients, heavy metals, and organic compounds) in the Izmir Bay. The Izmir Bay of western Turkey is one of the great natural bays of the Mediterranean Sea. The city of Izmir is an important industrial and commercial center and is a cultural focal point for this area. In this review, I review the results of studies performed by researchers over a period of two decades to glean what probable impact has resulted from human activities in the bay. I also summarize available data on the contamination levels found in the bay and the effects generated by these levels on the ecosystem of the bay. In addition, I provide a monitoring analysis that provides the distribution of inorganic nutrients and chlorophyll-a that have been investigated and the N/P ratios that were determined in Izmir Bay during 1996-2008. To identify the temporary trends in the monitoring data, linear regression analyses were performed. Significant negative trends were observed in TNOx concentrations in Izmir Bay. No significant trend was found in metal concentrations except Pb in the sediment. A significant negative existed for Hg in fish. Unfortunately, there are only limited data available for the organic contaminations from Izmir Bay. Therefore, any attempt to create a regional scale assessment from organic contaminant data available in the literature is limited by the scarcity of available information.