Abstrakt: |
A five-year extension to an ongoing epidemiology study has been undertaken. Mortality information was updated for an additional five years through 1985-1989 for 715 male hydrometallurgical nickel refinery employees who worked at Sherritt Gordon Limited in Fort Saskatchewan, Alberta, during the years 1954 to 1978. Mortality ascertainment was obtained using the Canadian Mortality Data Base, maintained by Statistics Canada, and covered the years 1954 through 1989. Cause-specific mortality analyses were accomplished for males, by age group and calendar year of death, for Canada and the province of Alberta. Total mortality was significantly below expectation (42 observed vs. 70 expected deaths for Canada, and 66 expected for Alberta). Statistically fewer observed deaths were found for circulatory disease while multiple myeloma and lymphoid malignancies demonstrated a statistically significant increase of observed deaths. Specific focus was directed at cancers of the respiratory system because of previous reports linking these conditions with exposure to nickel compounds in some workforces. No deaths due to nasal cavity or paranasal sinus cancer were detected among cohort or study group members. Four lung cancer deaths were found with five deaths expected for Canada and four expected for Alberta. To date, no association between exposure to nickel concentrate or metallic nickel and the subsequent development of respiratory cancer has been found in this study. The hydrometallurgical refinery operation is an enclosed process in contrast to other refinery processes such as pyrometallurgical and electrolytic. |