The relationship between mercury concentration in human organs and different predictor variables.

Samples from different tissues were collected from autopsies of individuals of the general population of the Stockholm area, Sweden. The samples were analysed for total mercury content using radiochemical neutron activation analysis. Average concentrations of mercury in occipital cortex, abdominal muscle, pituitary gland and kidney cortex were, 10.6 (2.4-28.7), 3.3 (0.9-5.4), 25.0 (6.3-77) and 229 (21.1-810) micrograms/kg wet weight, respectively. Possible predictor variables for mercury concentrations were tested in multiple linear regression models. An effect of a number of tooth surfaces with amalgam was seen in occipital lobe cortex, abdominal muscle and pituitary gland, but not in kidney cortex. In occipital lobe cortex and abdominal muscle, concentrations of mercury increased with age. Explanations discussed include: that a significant fraction of the mercury retained from amalgam fillings has a very long biological half-life; a decreasing capacity of mercury excretion with age; or higher fish consumption in the older individuals. In kidney cortex mercury concentrations decreased with age. The reason for this remains unclear, but it might indicate a decreasing capacity of mercury excretion with age. Chronic alcohol abuse was associated with decreased concentrations of mercury in occipital cortex.