This British study included 136 atomic-energy workers who died of prostate cancer. It addressed their occupational contamination by specific radionuclides, as compared to 404 matched co-worker controls. Internal contamination was assessed by whole body monitoring of individual radionuclides. This risk increased with duration of work at the buildings likely contaminated, and was higher in individuals working in heavy-water reactor environments. This study thus correlated radionuclide exposure with prostate cancer incidence, strongly supporting the role of these elements in prostate carcinogenesis in an occupational setting.
Nigerian men display a low incidence of prostate cancer, compared with other countries.
The authors analyzed, in a Nigerian population, zinc and cadmium levels in serum and prostate specimens from 55 subjects with no prostatic disease, and compared them with 60 men with prostate hyperplasia and 12 with Stage III-IV cancer. The relevance of these significant findings, apart from its diagnostic potential, was not addressed in this study. A Canadian study from Alberta, that contrasted the provincial geographic distribution of water, soil and food cadmium concentrations and prostate cancer incidence. 982 samples collected between 1969 and 1978 were used for cadmium measurements. The authors observed that two communities, Medicine Hat and Camrose, displayed higher and lower than average prostate cancer incidence, respectively.