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From a cohort of 6497 male employees of the Australian Blue Asbestos Company between 1943 and 1966, 2400 replied to a questionnaire on smoking in 1979. Forty-nine per cent stated that they were current smokers, 30% that they were ex-smokers and 21 % that they had never smoked. All current smokers were provided with information on the effects of smoking and counselled to stop by a letter containing smoking cessation advice. All subjects have been followed to December 1986 to obtain their vital status, date of diagnosis of cancer, or cause of death. The incidence of cancer and mortality have been examined according to the subjects' known exposure to crocidolite and smoking status. Further information on smoking status was obtained by mail in 1985 and 1989. The incidence rates for lung cancer and death rates from all causes in those who had never smoked have been applied to the current smokers and ex-smokers to predict the effect of stopping smoking in 1979. Smoking has made a major contribution to death and disease in this cohort of crocidolite workers. Forty per cent of the smoking-related excess deaths were due to lung cancer (in both current smokers and ex-smokers). There were 60 deaths attributable to smoking and 52 attributable to asbestos exposure between 1979 and 1986. If all subjects had never smoked there would have been about 30 (95% CI, 7–48) less cases of lung cancer and 60 (95% CI, −3 to 124) less deaths from all causes in this cohort by the end of 1986. If all subjects who smoked had quit in 1979 it is predicted that there would be about 130 fewer cases of lung cancer and 260 fewer deaths from all causes by the year 2010. [ABSTRACT FROM PUBLISHER]

Six thousand four hundred and ninety-seven men are known to have been employed in the mining and milling of crocidolite at Wittenoom, Western Australia, between 1943 and 1966. Employment was usually brief (median duration 4 months) and exposure intense (estimated median cumulative exposure 6 fibre-year ml−1). Most subjects had no previous or subsequent industrial exposure to asbestos minerals and in this respect represent a unique cohort. Follow-up has been completed to the end of 1986. Significant excess deaths were observed for malignant mesothelioma (pleura 77 deaths, peritoneum eight deaths), lung cancer (SMR 1.4), respiratory diseases (pneumoconiosis, SMR 10.7), infections (TB, SMR 2.5), mental disorders (alcoholism, SMR 2.4) and digestive diseases (peptic ulceration, SMR 1.6, and cirrhosis of the liver, SMR 1.5). Deaths from nontransport accidents (SMR 1.6) and unknown causes (SMR 1.7) were also increased. There was no significant increased mortality from laryngeal cancer (SMR 1.1), stomach cancer (SMR 1.2) or colorectal cancer (SMR 0.8). There was a significant association of mortality from malignant mesothelioma with duration of employment at Wittenoom and with intensity of crocidolite exposure. Lung cancer mortality was significantly associated with age, duration of employment and intensity of crocidolite exposure as was the incidence of compensable asbestosis. The excess city from tuberculosis may be attributed to the large proportion of immigrants in the workforce and the excess mortality from the other conditions to a high prevalence of smoking and excessive alcohol consumption in this cohort. [ABSTRACT FROM PUBLISHER]

The article presents a study which examines the asbestos health risk and cases of mesothelioma following an environmental crocidolite exposure in Wittenoom, Western Australia. The researchers have tested the exposure-response relationships between mesothelioma and crocidolite exposure at work environments of miners. The findings indicate an increasing incidence of malignant mesothelioma due to exposure of asbestos products like amphibole and chrysotile in Wittenoom.

Objectives: To estimate the relations between exposure to both tobacco smoke and crocidolite and the incidence of various histological types of lung cancer.Methods: In 1979 all former workers from the Wittenoom asbestos industry who could be traced were sent a questionnaire on smoking history. Of 2928 questionnaires sent, satisfactory replies were received from 2400 men and 149 women. Of the men, 80% had smoked at some time and 50% still smoked. Occupational exposure to crocidolite was known from employment records and follow up was maintained through death and cancer registries in Australia with histological diagnoses obtained from the relevant State Cancer Registry. Conditional logistic regression was used to estimate the effects of tobacco and asbestos exposure on incidence of different cell types of lung cancer in a nested case-control design.Results: Between 1979 and 1990, 71 cases of lung cancer occurred among men in this cohort: 27% squamous cell carcinoma, 31% adenocarcinoma, 18% small cell carcinoma, 11% large cell carcinoma, and 13% unclassified or indeterminate. Two of the classified cases and one unclassified case had never smoked. The incidence of both squamous and adenocarcinoma types of lung cancer were greatest in ex-smokers and in those subjects with the highest levels of exposure to crocidolite. After adjustment for smoking habit, the increase in incidence of lung cancer with increasing exposure to crocidolite was greater for squamous cell carcinoma than for adenocarcinoma.Conclusions: The results from this study have shown significant exposure-response effects for exposure to crocidolite, and both adenocarcinoma and squamous cell carcinoma of the lung. They also provide some further evidence against the theory that parenchymal fibrosis induced by asbestos is a necessary precursor to asbestos induced lung cancer. [ABSTRACT FROM AUTHOR]

The article presents a study to assess the exposure-response correlation of lung cancer and crocidolite of Wittenoon crocidolite employees in Australia. It features results of the cohort research on the lung cancer cases of the 6910 crocidolite employees in the country until December 1994. Moreover, it features the predictors of lung cancer among patients.