Environmental Quality Standards

What are Environmental Quality Standards?

Environmental Quality Standards (EQS) are similar to Water Quality Criteria in the United States. They are numerical limits to allowable concentrations of chemicals in water. Similar standards can also be used to control chemicals in other environmental media, as discussed in a book co-edited by Mark Crane.

The Water Framework Directive (WFD; 2000/60/EC) is one of the most important pieces of European environmental legislation of relevance to ecotoxicologists, requiring all inland and coastal waters to achieve ‘‘good status’’ by 2015. It does this by establishing a river basin district structure within which demanding environmental objectives are set, including ecological targets for surface waters and the use of EQS for individual chemical pollutants.

Article 16 of the Directive describes broadly how and by when EQS for pollutants should be developed:

  • Pollutants presenting a significant risk to or via water should be identified by the European Commission (EC) and classified as Priority Substances (PS), with the most hazardous of these classed as Priority Hazardous Substances (PHS). For PS and PHS, measures should aim at progressive reduction and cessation of discharges, respectively, by 2025. Priority substance lists should be reviewed at four year intervals.
  • Quality standards should be submitted by the EC that are applicable to concentrations of PS in surface water, sediments, or biota.

In 2008, the EC published an EQS “Daughter” Directive to the WFD to deal with the control of priority substances, which has now itself been replaced by an updated EQS Directive (2013/39/EU). In the new EQS Directive, EQS are set for surface waters or biota (usually fish) for 48 priority substances, 21 of which are identified as Priority Hazardous Substances. Annual Average EQS for surface waters are set for all of these substances except hexachlorobenzene, hexachlorobutadiene, and mercury for which only MACs and biota EQS have been set. Only biota EQS are set for dioxins and dioxin-like compounds. Sediment EQS have not been set because of the technical problems associated with these, but trends in sediment and biota concentrations of PS and PHS should be monitored by Member States. There is now comprehensive guidance on how to develop and monitor an EQS in different matrices which helps to ensure greater consistency between member states, and greater consistency between the development of EQS and the development of PNECs for the same substances across different European Regulations and Directives.

How can AG-HERA help you?

We can help you to develop EQS for water and (if necessary) sediments that are compliant with the Water Framework Directive and use only reliable, high quality data. We can also develop similar standards for other media. We can also provide and present robust advocacy in support of technically and economically defensible standards in meetings with regulatory authorities.

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