Review of heavy metal accumulation on aquatic environment in Northern East Mediterrenean Sea part I: some essential metals.

All pollutants can reach the aquatic environments and the levels of heavy metals in upper members of the food web like fish can reach values many times higher than those found in aquatic environment or in sediments. Although heavy metals are essential or non-essential, all heavy metals are potentially harmful to humans and most organisms at some level of exposure and absorption. Marine organisms are good indicators for long-term monitoring of metal accumulation. The present review study is for evaluation of the data from previous studies about the toxic effects of selected heavy metals, like essential metals (copper, zinc, iron, chromium, and manganese), on seawater, sediment, and in different tissues of aquatic animals (demersal and bentic fish, invertabres) collected from different areas in Northern East Mediterrenean Sea since the 1990s. Some concern arose from previous studies, particularly in terms of safety for human consumption. For this purpose, 86 articles and 4 theses were examined and information was collected on the table to open a forward-looking view of the pollution of studied area. In previous studies, the variations in feeding habits, habitats, and the level of copper found in edible muscles of the demersal fish species (deep water fish species, carnivore) such as Mullus barbatus barbatus, Solea lascaris, Sparus aurata were always higher than those found in pelagic (omnivore) Mugil cephalus, Liza aurata. Results show discrepancies caused by many factors; thus, more work must be done carefully.