Copper and zinc in human serum in Norway. Relationship to geography, sex and age.

Serum samples were collected from the adult population, age groups from 20 to 54 years, in 11 different Norwegian municipalities and analysed for zinc and copper by atomic absorption spectroscopy. Significant differences were found between several of the municipalities when the mean concentration of zinc in serum in 200 randomized samples were compared, with only two municipalities being different for copper. The values for zinc ranged from 13.8 to 18.3 mumol/l and copper varied between 16.3 and 19.2 mumol/l. An age related increase in the copper concentration was evident in the male population, and age-adjusted means showed a slight, but significantly higher serum copper concentration in females (18.4 mumol/l) than in males (16.5 mumol/l). For zinc the opposite sex-relationship was indicated with the highest values in males, 15.8 compared to 15.1 mumol/l in serum from females. No significant correlations were found between the concentrations of zinc and copper in serum. In all age groups of women, however, a small negative correlation was found giving a significant tendency.