Trace Metal Concentrations In The Offshore Surficial Sediments Of Heraklion Gulf (Crete Island, East Mediterranean Sea)

The present study investigates the distribution of trace metals (Fe, Mn, Cr, Zn, Pb, Cu and Al) as pollution indicators in the surficial inner shelf sediments along the northern coast of Heraklion Gulf (Crete Island). Despite the fact that Heraklion Gulf is an industrialized urban area, hosting the third most important commercial harbour in Greece, the levels of trace metals in sediments are not considerably high. According to Sediment Quality Guidelines (SQGs), the sediments are considered unpolluted with low probability of adverse effects on biota in the case of Cu, Zn and Pb, and moderately to heavily polluted in the case of Cr. Moreover, Zn, Cu and Pb concentrations are lower than those measured in a previous study (1989). This improvement in the environmental status of the study area is a response to more efficient control of terrestrial pollution sources, following the enforcement of Directive 91/271/EEC (as amended by Directive 98/15/EU) on urban wastewater treatment and disposal.