Seminal plasma trace metal levels in industrial workers

This study compares the seminal plasma trace metal levels of hospital workers with groups of industrial workers in a petroleum refinery, smelter, and chemical plant. The metals measured were the essential metals (copper, zinc, nickel, cobalt, and manganese) and the toxic metals (lead, cadmium, and aluminum). The group mean +/- SE metal level for each group (50 subjects per group) was calculated, and the statistical significance of the group mean differences of the industrial groups with the hospital group (control) was determined by the Student's t-test. The differences observed in the smelter group were increased copper and zinc (p less than or equal to 0.001) and decreased nickel, cobalt, and manganese (p less than or equal to 0.001, less than or equal to 0.01). The refinery group differences were increased copper, zinc, and nickel (p less than or equal to 0.001) but decreased cobalt and manganese (p less than or equal to 0.001). The chemical group differences were increased zinc (p less than or equal to 0.001) and decreased cobalt (p less than or equal to 0.001). The seminal plasma levels of the toxic metals lead and aluminum were increased in each of the industrial groups (p less than or equal to 0.001). Concurrent differences were (1) decreased accumulation of nickel, cobalt, and manganese in the smelter group, (2) decreased cobalt and manganese in the refinery group, and (3) only decreased cobalt in the chemical group.