Chromium, cobalt and lanthanum in lung, liver and kidney tissue from deceased smelter workers

Lung, liver and kidney tissue concentrations of chromium, cobalt and lanthanum from 66 deceased copper smelter workers have been compared with 14 controls. Samples were taken in connection with ordinary autopsies at the local hospital. Neutron activation analysis was used. The mean exposure time for the smelter workers was 30 y, the mean time to date of death after termination of exposure was 7.4 y. A four-fold increase of chromium (p = 0.001) and a two-fold increase of cobalt (p less than 0.001) and lanthanum (p = 0.013) in lung tissue was found for smelter workers compared to controls. Of the smelters nearly one third died from malignancies (approximately 10% from respiratory cancer) and approximately 45% from cardiovascular disease. In the control group nearly 80% died from cardiovascular diseases and no malignancies were found. In lung tissues the concentration of chromium, cobalt and lanthanum did not decline with time after exposure had ended, indicating a long biological half-time. The causes of death could not be related to a single factor. The findings indicate a multifactorial genesis.