Lung cancer in smelter workers--interactions of metals as indicated by tissue levels

The concentrations of the elements antimony, arsenic, cadmium, chromium, cobalt, lanthanum, lead, selenium, and zinc were determined in lung tissue of 85 decreased smelter workers by neutron activation analysis and atomic absorption spectrophotometry. The concentrations of all these elements, except zinc, were significantly higher among the workers as compared with rural referents. Workers who died from lung cancer (N = 7) had the lowest lung selenium content relative to other metals, both compared with workers with other diseases and with rural (N = 15) and urban (N = 10) referents. The low lung tissue levels may have influenced the development of lung cancer. The highest lung cadmium concentrations were observed in the lung cancer group, in which, however, smokers and ex-smokers were over-represented. The observations make it likely that the excess lung cancer risk in this smelter environment is multifactorial in character, involving interactions between both carcinogenic and anticarcinogenic factors.