Asbestos and malignant disease

Our plain-English summary of Asbestos and malignant disease, by R. Barnes (The Medical Journal of Australia, 1972).

The study

• Author: R. Barnes
• Journal: The Medical Journal of Australia
• Published: 1972;2(20):1107-12
• Cited by: 4 articles, as counted by NIH iCite
• Read it: PubMed · Publisher
• In J-M's library: Johns-Manville's company medical library held a copy (J-M no. 002416).

Summary of the article

This article described workers compensated for asbestosis under the New South Wales Workers' Compensation (Dust Diseases) Act, which was widened in 1967 to include asbestosis. Between February 1968 and the end of December 1971, the Dust Diseases Medical Authority recognized 51 claims for asbestosis. The author presented brief clinical histories of the 13 claimants who had since died, all men aged 44 to 66 years at assessment, covering exposure, smoking, symptoms, chest X-ray reports, pulmonary function and cause of death. Of the 13 deaths, 8 were from bronchogenic carcinoma and 3 from mesothelioma. One death was certified as myocardial infarction and one as congestive cardiac failure. The mean period from first exposure to death was 29.8 years for lung cancer and 29 years for mesothelioma. All who died of bronchogenic carcinoma were medium to heavy cigarette smokers. The mesothelioma deaths occurred at ages 49, 61 and 66 years. In none of these three cases was asbestosis obvious on X-ray, and no link with crocidolite rather than chrysotile could be found. The author noted bias: four patients were referred after a tumour had been diagnosed, leaving 7 malignant deaths among 13. An addendum reported that by August 1972, 15 of 19 deaths (74%) were from bronchogenic carcinoma or pleural mesothelioma. The author called for six-monthly review of compensated workers, a search for an asbestos substitute, and greater medical awareness of asbestos-related cancer.

PubMed has no abstract for this study, and the article doesn't print one. We wrote this summary from the full article with the help of AI. It is not the authors' wording.

In plain English

A medical officer of the Workers' Compensation (Dust Diseases) Board in Sydney described the 13 deaths among 51 people whose asbestosis claims were recognized in New South Wales from February 1968 to December 1971. All were men exposed at work, for example in asbestos products factories, mining, lagging and boiler-making. Eight died of bronchogenic carcinoma (lung cancer) and 3 of mesothelioma: 11 of 13 deaths (85%). The mean time from first exposure to death was 29.8 years for lung carcinoma and 29 years for mesothelioma. All who died of lung carcinoma were medium to heavy cigarette smokers. None of the three mesothelioma cases showed obvious asbestosis on X-ray in lung areas not hidden by the tumour. In none could a link to crocidolite rather than chrysotile be found. The author noted the series was heavily weighted: three men were referred from hospitals after tumour diagnosis, and one by his firm after a diagnosis of probable mesothelioma. This still left 7 malignant deaths of 13. The author concluded that these cases added weight to the need for an asbestos substitute.

We wrote this plain-English summary from the full article with the help of AI, and a second AI model checked each sentence against the article. It is not the authors' wording; the abstract and the article are their own account.

What the study did and found

• Design: case series: brief clinical histories of compensation claimants who died, with a summary table
• Who was studied: 51 people with asbestosis claims recognized by the Dust Diseases Medical Authority, New South Wales, February 1968 to December 1971. The case histories cover the 13 who died, all men aged 45 to 66 at death.
• Exposure: Occupational asbestos exposure of 10 to 40 years. Jobs included:
• asbestos products factories, including the 'blow room', where dust counts were very high
• an asbestos mine
• asbestos sheet cutting and moulding
• pipe manufacture, lagging and spraying
• boiler-making with stripping of old lagging

Estimated dust concentrations in Table 1 ranged up to 100 fibres per cubic centimetre.

• Main results:
  • Of the 13 deaths among the 51 claimants, 8 were from bronchogenic carcinoma and 3 from mesothelioma.
  • Malignant disease accounted for 11 of the 13 deaths (85%).
  • The mean period from first exposure to death was 29.8 years for lung carcinoma and 29 years for mesothelioma.
  • All patients who died from bronchogenic carcinoma were medium to heavy cigarette smokers. The author called this highly significant. The printed p-value is garbled but appears to lie between 0.001 and 0.002.
  • In the three mesothelioma cases, industrial exposure lasted 22, 24 and 29 years. In none was asbestosis obvious on the X-ray films of the lung areas not hidden by the tumour.
  • The mesothelioma deaths occurred at ages 49, 61 and 66. These were younger than the average age at death from other causes.
  • In none of the three mesothelioma cases could an association with crocidolite rather than chrysotile be found.
  • Four patients were referred in ways that weighted the series. Three were referred from hospitals after tumour diagnosis, and one was referred by his firm. Allowing for these, 7 of the 13 deaths were still from malignant lung lesions.
  • Addendum, to the end of August 1972 (87 compensated): of 19 deaths among workers given asbestosis awards, 15 were due to bronchogenic carcinoma or pleural mesothelioma, printed as 74%. After adjusting for referral bias, the author gave an adjusted malignancy rate of 50%.
• The authors' conclusion: The author concluded that these cases, together with many others reported, add weight to the need to search for a substitute for asbestos without such carcinogenic effects. The author also asked doctors to be aware of the association of bronchogenic carcinoma and mesothelioma with asbestos exposure.
• Limitations the authors state:
  • The number of asbestosis cases in New South Wales industry could not be properly assessed, because the condition had been compensable for only three and a half years.
  • Post-mortem examination is not required in New South Wales, and the Board often learns of deaths late. As a result, pathological investigations were incomplete for some workers.
  • The series is heavily weighted because three patients were referred from hospitals after their tumour was diagnosed and one was referred by the firm.

Topics

The National Library of Medicine indexes this study under subjects our site covers: Lung cancer, Mesothelioma.

Medical terms in this study, explained in our Lexicon: Chest X-Ray, Bronchogenic Carcinoma, Mesothelioma, Lung Cancer, Crocidolite, Chrysotile, Pleural Mesothelioma.

Related studies

• Conventional and high resolution computed tomography in the diagnosis of asbestos-related diseases — D.A. Lynch, G. Gamsu, et al. (1989)
• Malignant pleural disease — L. Bonomo, B. Feragalli, et al. (2000)
• Asbestos related disease — H.L. Hardy (1965)
• Combined effect of asbestos exposure and smoking on mortality from lung cancer in factory workers — G. Berry, M.L. Newhouse, et al. (1972)
• Possible cellular and molecular mechanisms for asbestos carcinogenicity — C. Walker, J. Everitt, et al. (1992)
• Pulmonary fibrosis, carcinoma, and ferruginous body counts in amosite asbestos workers. A study of six cases — V.L. Roggli, S.D. Greenberg, et al. (1980)

Browse more research in The Medical Journal of Australia, or return to medical research.