Report of the Working Group on Marine Sediments in Relation to Pollution (WGMS)

OSPARMON made a preliminary assessment of the geographical distribution of ratios between contaminant (PAH, CB) concentrations. In some cases, an apparent change in ratios was observed to coincide with boundaries between data from different countries in the same general area (e.g. Southern Bight of the North Sea). These systematic differences were found to correlate with results from the QUASIMEME Laboratory Proficiency Schemes. This work will be elaborated further with a view on reporting the progress to OSPAR-MON 2007.