The Analysis of Trace Metals in Biological Reference Materials: A Discussion of the Results of the Intercomparison Studies Conducted by the International Council for the Exploration of the Sea

Abstract

The reference materials used in these exercises were prepared from fish and shellfish tissue and distributed in the main to laboratories within the ICES framework which were participating in the ICES fish and shellfish pollution monitoring programme.

The results of these exercises showed that there was a progressive improvement in the comparability of analytical results of Cu, Zn and Hg at concentrations normally found in fish and shellfish tissue i.e. 30–280 pmol kg⁻¹ (dry wt), 350–1000 pmol Zn kg⁻¹ (dry wt) and 0.25–4.0 pmol Hg kg⁻¹ (dry wt). However, the results of the Cd and Pb analysts were in general not as encouraging. The range of values reported by participants for these metals covered more than an order of magnitude at tissue concentrations in the ranges 0.009–0.9 pmol Cd kg⁻¹ (dry wt) and 0.024–4.8 umol Pb kg⁻¹. The most recent exercise for Cd and Pb showed that comparable data was obtained for tissue concentrations of 10 pmol kg⁻¹ (dry wt) and 12 pmol kg⁻¹ (dry wt) respectively i.e. concentrations normally found in shellfish tissue.