Respiratory cancer mortality and incidence in an updated cohort of Canadian nickel production workers

ABSTRACT

Respiratory cancer mortality and incidence were examined in an updated cohort of >56,000 Canadian nickel mining and refining workers. There was little evidence to suggest increased lung cancer risk in workers who had no experience in high-risk sintering operations that were closed by 1972, apart from that which would be expected from probable increased smoking prevalence relative to the comparison population. There was no substantive evidence of increased laryngeal cancer risk in the cohort, nor was there evidence of increased pharyngeal cancer risk in nonsinter workers. Nasal cancer incidence was elevated in nonsinter workers, but excess risks appeared to be confined to those hired prior to 1960. These findings lead us to tentatively conclude that occupationally-related respiratory risks in workers hired over the past 45 years are either very low or nonexistent.

KEYWORDS:

• Cohort
• nickel
• occupational epidemiology
• respiratory cancer

Acknowledgments

We extend thanks to Robert Semenciw of the Public Health Agency of Canada for supplying and running some statistical programs and to Statistics Canada for supplying health data and the record linkage for the study. We also thank a reviewer whose comments improved the article considerably.

Disclosure statement

The article underwent review by both union and management representatives. Data interpretations in this article represent the independent scientific views of the authors.

Funding

Funding for the study was provided by Vale Canada Ltd.