NOAA National Status and Trends Program : seventh round intercomparison exercise results for trace metals in marine sediments and biological tissues

"This report, prepared by the National Research Council of Canada, summarizes results of the NOAA National Status and Trends Program seventh round intercomparison exercise for trace metals in marine sediments and biological tissues. This exercise is one in a series of annual intercomparisons sponsored by NOAA and EPA for laboratories doing agency-funded chemical analyses. In addition, the exercises have been opened to other laboratories resulting in fiftynine laboratories receiving materials for analysis for the 1993 exercise. The exercise materials were a freeze dried mussel tissue collected off the coast of France and a freeze dried marine sediment collected in the Mississippi Delta. Reference materials NRC CRM BCSS-1 and NIST SRM 1566a were also analyzed as part of the exercise. The elements determined were Al, Cr, Fe, Ni, Cu, Zn, As, Se, Ag, Cd, Sn, Hg and Pb for both matrices, plus Be, Si, Mn, Sb and Tl for sediments. Forty-eight sets of results were received."