Mortality and cancer incidence in workers in two Australian prebake aluminium smelters
- M R Sim1,
- A Del Monaco1,
- J L Hoving2,
- E MacFarlane1,
- D McKenzie1,
- G Benke1,
- N de Klerk3,
- L Fritschi4
- 1 Department of Epidemiology and Preventive Medicine, Monash University, Melbourne, Australia
- 2 Coronel Institute of Occupational Health, Universiteit van Amsterdam, Amsterdam, The Netherlands
- 3 Telethon Institute for Child Health Research, West Perth, Australia
- 4 Western Australian Institute for Medical Research, Sir Charles Gairdner Hospital, Nedlands, Australia
- Malcolm R Sim, Monash Centre for Occupational & Environmental Health (MonCOEH), Department of Epidemiology & Preventive Medicine, Faculty of Medicine, Nursing and Health Sciences, Monash University, Alfred Hospital, Commercial Road, Melbourne Victoria 3004, Australia;
- Revised 30 January 2009
- Published Online First 12 February 2009
Background: Exposures in the aluminium production industry have been declining and this study aimed to investigate cancer and mortality in two Australian prebake aluminium smelters.
Methods: The cohort included 4396 males who had worked in a prebake smelter for at least 3 months. They were matched against the National Death Index and the National Cancer Statistics Clearing House to obtain cause of death and type of cancer. Standardised Mortality Ratios (SMRs) and Standardised Incidence Ratios (SIRs) were calculated for the whole cohort, for production or maintenance work categories and for duration of employment categories.
Results: The SMRs for all causes, circulatory, respiratory and injury deaths were at or below expected. Mesothelioma was the only significantly increased cause of death (SMR 3.52, 95% CI 1.47 to 8.46). Death from prostate cancer in production workers was elevated (SMR 2.39, 95% CI 1.29 to 4.44) and in those who had worked for more than 20 years in production or maintenance jobs (SMR 3.67, 95% CI 1.53 to 8.81). There were statistically significant excesses of incident stomach cancer, mesothelioma, and kidney cancer cases, while the SIR for melanoma was significantly reduced. There was no significant trend for duration of exposure for any type of incident cancer.
Conclusions: This study found no overall excess of mortality or cancer, but incident mesothelioma and kidney cancer risks were elevated. The lack of excess risk for lung or bladder cancer or deaths from respiratory disease may be related to the different level and pattern of exposure between Søderberg and prebake smelters.
Competing interests: None declared.
Funding: The study was funded by Alcoa of Australia Ltd. The study sponsor provided comments to the researchers on the study design and this manuscript through their representation on the study Advisory Board. The decision to submit this paper for publication was the researchers’ decision alone. The sponsor also assisted in data collection, especially for extraction of required data from personnel records.
Ethics approval: Ethics committee approval was granted for the Healthwise Cancer and Mortality Study by the Monash University Standing Committee on Ethics in Research Involving Humans, The University of Western Australia Human Research Ethics Committee and ethics committees for the AIHW and each of the eight State and Territory cancer registries.