Concentrations of trace metals in phytoplankton and zooplankton in the Gulf of Gabès, Tunisia

Abstract The concentrations of four trace metals (Cd, Cu, Pb, and Zn) were investigated for the first time in phytoplankton, zooplankton, and the seawater samples collected from the coast of Gabes, Tunisia, Mediterranean Sea. For over 40 years, this coast has witnessed significant anthropogenic impacts form fertilizer processing. Results obtained for Cd, Cu, Pb, and Zn in seawater far exceed the concentration reported for other Mediterranean coastal waters, highlighting the Gulf of Gabes as a pollution hotspot. The average metals concentration was in the order Zn > Pb > Cu > Cd in water, and phytoplankton, whereas Pb > Zn > Cu > Cd in zooplankton. The biomagnification in phytoplankton and zooplankton for Zn, Pb, Cu, and Cd was 116, 56, 38, 31, and 127, 157, 30 and 27. The biomagnification of Zn and Pb was higher in zooplankton than phytoplankton, while Cu and Cd were higher in phytoplankton.