Blood trace metals in military recruits

Whole blood samples obtained from 2,000 military recruits were analyzed for cadmium, copper, lead, and zinc by atomic absorption spectroscopy. Whole blood copper levels were symmetrically distributed and those for cadmium, lead, and zinc were positively skewed. Average whole blood levels for copper and zinc were generally comparable to published values, but cadmium and lead values were somewhat higher, suggesting possible absorption of trace metals from containers during storage. Average cadmium and zinc levels were similar among blacks and whites, whereas average copper and lead levels were significantly higher in blacks. Cigarette smokers had higher copper levels than nonsmokers. Cadmium and zinc whole blood levels varied inversely with educational attainment. Copper, lead, and zinc levels varied by place of residence, suggesting the influence of dietary or other factors. Future studies characterizing trace metal body burdens or relating trace metals to diseases must carefully measure such pertinent attributes as age, sex, race or ethnic group, smoking habits, diet, and environmental exposure.