Cohorts of Finnish asbestos sprayers and of asbestosis and silicosis patients were followed for cancer with the aid of the Finnish Cancer Registry in the period 1967-1994. Compared with the cancer incidence of the total Finnish population, asbestos sprayers had an increased risk for total cancer (standardized incidence ratio [SIR] 6.7, 95% confidence interval [95% CI] 4.2-10); lung cancer (SIR 17.95% CI 8.2-31); and mesothelioma (SIR 263, 95% CI 85-614). The SIR of the asbestosis patients was 3.7 (95% CI 2.8-5.0) for all sites, 10 (95% CI 6.9-14) for lung cancer, and 65 (95% CI 13-188) for mesothelioma. The silicosis patients also had significantly high SIR values for all sites (1.5, 95% CI 1.0-2.1) and lung cancer (2.7, 95% CI 1.5-4.5). The values for the SIR and the standardized mortality ratio for all sites and lung cancer were very similar, and therefore it seems that both are reliable indicators of the occurrence of occupational cancer. It was concluded that pneumoconioses patients and asbestos-exposed workers have a markedly elevated risk for cancer. Asbestos-induced occupational cancers are not only diseases of the elderly, since the relative risk is high also for middle-aged people.
Some previous studies have observed an increased mortality regarding ischemic heart disease (IHD) among miners and industrial sand workers. The purpose was to study the occurrence of IHD mortality among silica-exposed workers.
Male miners, well borers, dressing plant workers, and other mine and stone workers were identified in the Swedish National Census of 1970. The total cohort (n = 11,896) was followed from 1970 until December 31, 1995 and linked to the Cause of Death Register. The referent group comprised all gainfully employed men identified in the same census. The Standardized Mortality Ratio was calculated as the ratio between observed and expected numbers of deaths.
An increased risk due to IHD mortality was observed among miners, well borers, dressing plant workers, and other mine and stone workers.
These results indicate a possible relation between silica-dust exposure and IHD. The increased risk of IHD mortality is unlikely explained by smoking habits. Shift work might explain some of the increased risk. A low-grade inflammation in the lungs as a result of dust exposure is discussed as a possible cause. However, the key message is that better dose estimates and better confounding control is needed to study the possible relation between silica-dust exposure and IHD.
We investigated mortality among 1,190 Ontario miners who received Workmen's Compensation awards for silicosis from 1940 through 1975. In comparison with the general population of Ontario these men had elevated all-cause mortality rates, with deaths attributed to nonmalignant respiratory diseases and tuberculosis being primarily responsible. The group of miners receiving their compensation awards between 1940 and 1959 has experienced more than twice as many lung cancer deaths as expected while men receiving compensation awards after 1959 have had lung cancer rates similar to the general population. It is concluded that silicosis is not a benign disease and that efforts must be continued to prevent its occurrence.
The mortality experience of 1190 miners and 289 surface industry workers receiving workers' compensation awards for silicosis in Ontario since 1940 has been studied up to mid-1985. Both groups were found to have a significantly increased mortality from lung cancer (miners' SMR: 230; surface workers' SMR: 302) and stomach cancer (miners' SMR: 188; surface workers' SMR: 366). Adjustment for smoking and country of origin did not explain the excesses observed. The lung cancer findings are consistent with observations from silicosis registries in Europe. Possible explanatory factors are discussed.
Cites: J Natl Cancer Inst. 1972 Jul;49(1):81-914338782
Cites: Scand J Work Environ Health. 1980;6 Suppl 2:1-867384772
Cites: Lancet. 1982 Jul 17;2(8290):1506123852
Cites: Am J Ind Med. 1986;9(2):189-2013963000
Cites: Am J Ind Med. 1983;4(6):705-236316782
Cites: Can Med Assoc J. 1984 Feb 15;130(4):399-4056692236