Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0032273 (pneumoconiosis)
 1,578 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

It is known that 6505 men and 411 women were employed in the mining and milling of crocidolite at Wittenoom in the Pilbara region of Western Australia between 1943 and 1966. Employment was usually brief (median duration four months) and exposure intense (median estimated cumulative exposure 6 fibres/cc years). The vital status of 73% of the men and 58% of the women employed in the industry was known at 31 December 1980, providing 95 264 person-years of follow up with 820 deaths in men and 4914 person-years with 23 deaths in women. The standardised mortality ratio (SMR) for all causes in men was 1.53 (95% confidence interval 1.43 to 1.64). Statistically significant excess death rates were observed in men for neoplasms, particularly malignant mesothelioma (32 deaths), neoplasms of the trachea, bronchus, and lung (SMR 2.64), and neoplasms of the stomach (SMR 1.90); respiratory diseases, particularly pneumoconiosis (SMR 25.5); infections, particularly tuberculosis (SMR 4.09); mental disorders particularly alcoholism (SMR 4.87); digestive diseases, particularly peptic ulceration (SMR 2.46) and cirrhosis of the liver (SMR 3.94); and injuries and poisonings, particularly non-transport accidents (SMR 2.36). The excess mortality from pneumoconiosis, malignant mesothelioma, and respiratory cancers, but not stomach neoplasms, was dependent on time since first exposure and cumulative exposure. There was no increase in mortality from laryngeal cancer (SMR 1.09) or neoplasms other than those listed. The SMR for all causes in women was 1.47 (95% confidence interval 0.98-2.21) and for neoplasms 1.99; there was one death from malignant pleural mesothelioma.
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PMID:Mortality in miners and millers of crocidolite in Western Australia. 282 59

To define the relationships between chrysotile exposure in fibre terms and death from specific cancers, and pneumoconiosis, all 11,379 persons born 1891-1920 who had worked in the asbestos mines and mills of Quebec for a month or more before 1967 were followed to the end of 1975. Among the 10,939 men, there had been 4,463 deaths, 634 from these causes. For each death, referents were randomly selected from among men in the cohort born in the same year as the case and known to have survived to a greater age. For each case and his referents, exposures accumulated up to nine years before the death of the case had been obtained as (million particles per cubic foot) x years. Fibre counts were estimated for each work-place so that all exposures could be expressed in (fibres/ml) x years. The ratio of the means for all 2,586 accumulated exposures was 3.46 (f/ml)/mpcf. Relative Risks (RR) were related to exposure by matched analysis. For pneumoconiosis and lung cancer, RR = 1 + b.(f/ml).y fitted well, with b estimated as 0.00647 and 0.00038, respectively. For cancers of upper and of lower G.I. tract, severe exposure was associated with elevated RRs, but rather unclearly. For other abdominal cancers, and laryngeal cancer, risks and exposure were not positively associated. The asbestos-smoking interaction in lung cancer was closer to multiplicative than to additive.
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PMID:Fibre exposure and mortality from pneumoconiosis, respiratory and abdominal malignancies in chrysotile production in Quebec, 1926-75. 649 36

We report a further follow-up of a birth cohort of 11 379 workers exposed to chrysotile. The cohort consisted of 10 939 men and 440 women, born 1891-1920, who had worked for at least a month in the mines and mills of Asbestos and Thetford Mines in Quebec. For all subjects, length of service and estimates of accumulated dust exposure were obtained, with a smoking history for the vast majority. Three methods of analysis, two based on the "man-years" methods, the other a "case-and-multiple-controls" approach, gave results consistent with one another and with previous analyses. By the end of 1975, 4463 men and 84 women had died. Among men, the overall excess mortality, 1926-75 was 2% at Asbestos and 10% at Thetford Mines, much the dustier region. The women, mostly employed at Asbestos, had a standardised mortality ratio (SMR) all causes, 1936-75) of 0.90. Analysis of deaths 20 years or more after first employment showed that in men with short service (less than five years) there was no discernible correlation with dust exposure. Among men employed at least 20 years, there were clear excesses in those exposed to the heaviest dust concentrations. Reanalysis in terms of exposure to age 45 showed definite and consistent trends for SMRs for total mortality, for lung cancer, and for pneumoconiosis to be higher the heavier the exposure. The response to increasing dose was effectively linear for lung cancer and for pneumoconiosis. Lung cancer deaths occurred in non-smokers, and showed a greater increase of incidence with increasing exposure than did lung cancer in smokers, but there was insufficient evidence to distinguish between multiplicative and additive risk models. There were no excess deaths from laryngeal cancer, but a clear association with smoking. Ten men and one woman died from pleural mesothelioma. If the only subjects studied had been the 1904 men with at least 20 years' employment in the lower dust concentrations, averaging 6.6 million particles per cubic foot (or about 20 fibres/cc), excess mortality would not have been considered statistically significant, except for pneumoconiosis. The inability of such a large epidemiological survey to detect increased risk at what, today, are considered unacceptable dust concentrations, and the consequent importance of exposure-response models are therefore emphasised.
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PMID:Dust exposure and mortality in chrysotile mining, 1910-75. 737 Jan 89

This paper draws together the mortality experience for a cohort of some 11000 male Quebec Chrysotile miners and millers, reported at intervals since 1971 and now again updated. Of the 10918 men in the complete cohort, 1138 were lost to view, almost all never traced after employment of only a month or two before 1935; the other 9780 men were traced into 1992. Of these, 8009 (82%) are known to have died: 657 from lung cancer, 38 from mesotheliona, 1205 from other malignant disease, 108 from pneumoconiosis and 561 from other non-malignant respiratory diseases (excluding tuberculosis). After early fluctuations. SMRs (all causes) against Quebec rates have been reasonably steady since about 1945. For men first employed in Asbestos, mine or factory, they were very much what might have been expected for a blue collar population without any hazardous exposure. SMRs in the Thetford Mines area were almost 8% higher, but in line with anecdotal evidence concerning socio-economic status. At exposures below 300 (million particles per cubic foot) x years, (mpcf.y), equivalent to roughly 1000 (fibres/ml) x years-or, say, 10 years in the 1940s at 80 (fibres/ml)-findings were as follows. There were no discernible associations of degree of exposure and SMRs, whether for all causes of death or for all the specific cancer sites examined. The average SMRs were 1.07 (all causes), and 1.16, 0.93, 1.03 and 1.21, respectively, for gastric, other abdominal, laryngeal and lung cancer. Men whose exposures were less then 300 mpcf.y suffered almost one-half of the 146 deaths from pneumoconiosis or mesothelioma; the elimination of these two causes would have reduced these men's SMR (all causes) from 1.07 to approximately 1.06. Thus it is concluded from the viewpoint of mortality that exposure in this industry to less than 300 mpcf.y has been essentially innocuous, although there was a small risk or pneumoconiosis or mesothelioma. Higher exposures have, however, led to excesses, increasing with degree of exposure, of mortality from all causes, and from lung cancer and stomach cancer, but such exposures, of at least 300 mpcf.y, are several orders of magnitude more severe than any that have been seen for many years. The effects of cigarette smoking were much more deleterious than those of dust exposure, not only for lung cancer (the SMR for smokers of 20+ cigarettes a day being 4.6 times higher than that for non-smokers), but also for stomach cancer (2.0 times higher), laryngeal cancer (2.9 times higher), and-most importantly-for all causes (1.6 times higher).
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PMID:The 1891-1920 birth cohort of Quebec chrysotile miners and millers: development from 1904 and mortality to 1992. 1141 50