Estimation of heavy metal loads from Tiber River to the Tyrrhenian Sea and environmental quality assessment.

In order to evaluate the heavy metal pollution in the Tiber River and its environmental impact on the Tyrrhenian Sea (Central Mediterranean Sea), eight heavy metals (As, Hg, Cd, Cr, Cu, Ni, Pb and Zn) were determined in the water dissolved phase, suspended particulate matter and sediment samples collected from 21 sites in different seasons. Total heavy metal concentrations ranged from 34.88 to 4201.23 μg L-1 in water (as the sum of the water dissolved phase and suspended particulate matter) and from 42.81 to 1686.84 mg kg-1 in sediment samples. The total selected heavy metal load contribution into the sea is calculated in about 21,257.85 kg year-1, showing that this River should account as one of the main contribution sources of heavy metals in the Mediterranean Sea. In relation to the ecological assessment, the Tiber River and Estuary would be considered as an area in which the ecological integrity is possibly at risk.