Ecological risk and estimates of organophosphate pesticides loads into the Central Mediterranean Sea from Volturno River, the river of the “Land of Fires” area, southern Italy

The organophosphate pesticides pollution in the Volturno River and its environmental impact on the Tyrrhenian Sea (Central Mediterranean Sea) were estimated. Eight selected organophosphate pesticides (diazinon, dimethoate, malathion, chlorpyrifos, pirimiphos-methyl, fenitrothion, methidathion and tolclofos-methyl) were determined in the water dissolved phase, suspended particulate matter and sediment samples collected from 10 sites in different seasons. Total organophosphate pesticides concentrations ranged from 0.12 to 65.09 ng L-1 in water (as the sum of the water dissolved phase and suspended particulate matter) and from 1.19 to 23.17 ng g-1 in sediment samples. It has been calculated that the discharge of pollutants from the Volturno river into the Tyrrhenian Sea was about 71.815, 31 g year-1; for this reason the river is to be considered one of the main mouths of organophosphate pesticides in the Tyrrhenian Sea. In relation to environmental risk assessment, the concentrations of most OPPs in water and sediments from the Volturno River and its estuary were lower than guideline values, but the mean concentration of chlorpyrifos (5.41 ng L-1) in the Volturno River and Estuary has been shown that the ecological integrity of the river watercourse is possibly at risk.