Problems in establishing norm values for nickel and chromium concentrations in human pulmonary tissue

In 15 random autopsies, nickel (Ni) and chromium (Cr) were determined quantitatively by atomic absorption spectrometry (AAS) in human lung tissue to evaluate norm values. None of the deceased persons had had an occupational exposure to Cr or Ni or their compounds. In all, 22 tissue samples were taken from each lung at specific topographical anatomical locations. The analytical procedure is described in detail. The results showed substantial variation in concentrations both within a single lung and also between individuals. Median values found were 204 ng/g for Cr and 25.6 ng/g for Ni. Topographical concentrations of Cr and Ni were 1.3-1.9 times higher in the upper lung areas. In view of the variability in metal concentration, analysis of only one part of lung tissue is not sufficient for determining the content of the entire lung. The evaluation of norm values is an important precondition for appraisal of Cr and Ni accumulation in human pulmonary tissue that may be due to occupational exposure.