Hazardous substances in the water, biota and sediments of the North Estonian coastal sea

Abstract

The paper gives an overview of Estonian experiences with hazardous substances monitoring, as well as some recent results on this kind of monitoring in the aquatic environment, biota and sediments of the heavily industrialized North Estonia. Owing to its specific local conditions, the present list of priority hazardous substances of Estonia includes 1-and 2-basic phenols, heavy metals (Cr, Cu, Ni, Zn) and persistent organic pollutants (HCH, HCB, PCB, DDT, PCDD, PCDF, DL-PCB). The concentrations of hazardous substances in the sea and surface waters are currently low, but elevated concentrations may appear in bottom sediments of river estuaries and in fat tissues of fish. During recent decades the state of the North Estonian environment regarding the hazardous substances has continuously improved due to a decreased pollution load, ban of certain compounds, self-purification processes and sinks.

Ecosystem Services in the Baltic Sea

“…Substances include different metals such as cadmium, mercury, lead and zinc as well as persistent organic pollutants (POP) including PCB and DDT. There are large proportions that have been assimilated in organisms such as invertebrates (Hendozko 2010) and fish (Voigt 2007) as well as sediments (Roots et al 2010); they will persist in the system in decades to come. The input from some substances has decreased but the problem remains.…”