Risk assessment and prioritization of pollutants in continental Mediterranean waters based on hazard quotients

The input of chemical pollutants into the aquatic environment is growing but their potential adverse effects on the ecosystem still remain largely unknown. Therefore the development of appropriate risk assessment procedures capable to provide a prioritization of potential pollutants becomes necessary. Here we identify priority compounds specific to Mediterranean rivers and compare them to those found in other rivers worldwide. To this purpose hazard quotients (HQ) defined as the ratio of measured environmental concentration (MEC) to predicted non effect concentration (PNEC) referred to different trophic levels were calculated for different compounds selected from different existing prioritization schemes, as well as 15 priority substances identified under the Water Framework Directive (WFD) and compared for cases of Mediterranean vs. North European and USA rivers.This study has been financially supported by the EU through the FP7 project GLOBAQUA (Grant Agreement No. 605629) and by the Spanish Ministry of Economy and Competitiveness [project Consolider- Ingenio 2010 SCARCE CSD2009-00065], and was partly supported by the Generalitat de Catalunya (Consolidated Research Group: Water and Soil Quality Unit 2009-SGR-965). M. Kuzmanovic acknowledges AGAUR fellowship from the Generalitat de Catalunya.Peer reviewe