Analytical advances and changing perceptions of environmental heavy metals

Abstract

The past decade has seen some dramatic changes in our understanding of the environmental levels, exposure pathways and uptake of heavy metals by man. It is now increasingly clear that the human body burden of lead in industrialised countries is commonly several times higher than in remote areas, and possibly orders of magnitude higher than “natural” levels. A growing appreciation of the extent to which gross contamination during sampling and analysis has contributed to extremely inaccurate analyses, and the associated improvements in analytical reliability, has been the most important factor in changing our perception of man’s role in the distribution of environmental heavy metals.

Published interlaboratory analysis trials clearly show extreme unreliability of analyses during the late 1960’s and early 1970’s, but greatly improved performance in the late 1970’s. The difficulties in heavy metal analyses at trace or ultra-trace levels are such that no laboratory should consider undertaking such work without establishing and maintaining an adequate analytical quality control programme to demonstrate reliability and identify deficiencies as they arise.

Keywords:

• Environmental heavy metals
• analytical quality control
• interlaboratory studies
• blood lead
• contamination control