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Levels and trends in marine contaminants and their biological effects – CEMP Assessment report 2013

The full assessment is available online at: and through the interactive map below.

The CEMP assessment measured progress towards the OSPAR objective of having concentrations of hazardous substances at background levels, or close to zero, by 2020. Concentrations of metals, PCBs, and PAHs were generally stable or decreasing. In biota, 73, 87 and 96% of significant time trends were downwards for metals, PAHs and PCBs respectively. In sediment, the corresponding values were 72, 93 and 91%. For both biota and sediment, only about half of the parameters assessed showed any upward trends
and only metal concentrations increased at more than four stations. Cadmium, mercury, lead, and copper concentrations increased at 20, 16, 12, and 8 biota stations respectively; arsenic, copper, chromium, nickel and lead concentrations increased at 14, 14, 7, 5 and 5 sediment stations respectively.

This report focuses in particular on the assessment of CEMP data on TBT and its biological effects, as well as on contamination by copper:

Full Report

  • Concentrations of the antifouling agent TBT and biological effects in marine gastropods resulting from its use have also decreased following the ban on the use of TBT on pleasure boats in 1987 and on all ships in 2001. TBT concentrations decreased significantly in 55% of sediment time series and 81% of biota time series, and the biological effect vas deference index decreased significantly in 61% of time series. Copper is also used as an antifouling agent, and the assessment results for TBT and Cu are addressed in this report. For the information on TBT/Imposex, a separate Assessment Sheet is published by OSPAR alongside this report; 
  • 7% of the 202 copper time series in sediment were increasing and 11% were decreasing. Most of the upward trends are seen in the vicinity of harbours, marinas and major shipping lanes where concentrations are already at levels possibly causing effects to the ecosystem. The increasing concentrations in sediments should be investigated further and the sources and pathways into the sediment clarified.

These CEMP Assessment results can be consulted in full detail online at