Monitoring of priority hazardous substances in Estonian water bodies and in the coastal Baltic Sea

The water sub-programme of the Estonian National Environmental Monitoring Programme aims to monitor and to develop an information support system for the protection of inland surface waters, transitional waters, coastal waters and groundwater. Focusing on problem areas and reflecting intensive human impact, monitoring of hazardous substances is targeted at populated industrial metropolitan areas in Tallinn and in the oil-shale region of north-eastern Estonia. During the last decade the state of the environment regarding priority hazardous substances has continuously improved. According to monitoring results, the concentration of hazardous substances in sediments and in surface water remains low in the majority of Estonian rivers, and their quality by European standards is classified as good. Concentrations of hazardous substances found in Baltic fish in the Estonian coastal sea remain below standards established by the FAO/WHO for food. The key to the improvement of monitoring is the integration of source-oriented and load-oriented approaches, since both are lacking full-scale consistent data coverage.