The Wittenoom legacy

Our plain-English summary of The Wittenoom legacy, by A.W.B. Musk, A. Reid, N. Olsen, et al (International Journal of Epidemiology, 2020).

The study

• Authors: A.W.B. Musk, A. Reid, N. Olsen, M. Hobbs, B. Armstrong, P. Franklin, J. Hui, L. Layman, E. Merler, F. Brims, H. Alfonso, K. Shilkin, N. Sodhi-Berry, N. de Klerk
• Journal: International Journal of Epidemiology
• Published: 2020;49(2):467-476
• Cited by: 13 articles, as counted by NIH iCite
• Read it: PubMed · Publisher

Abstract

The Wittenoom crocidolite (blue asbestos) mine and mill ceased operating in 1966. The impact of this industry on asbestos-related disease in Western Australia has been immense. Use of the employment records of the Australian Blue Asbestos Company and records of the Wittenoom township residents has permitted two cohorts of people with virtually exclusive exposure to crocidolite to be assembled and studied. Follow-up of these two cohorts has been conducted through data linkage with available hospital, mortality and cancer records. The evolution of asbestos-related disease has been recorded and, with the establishment of exposure measurements, quantitative exposure-response relationships have been estimated. There has been an ongoing epidemic of mortality from lung cancer and malignant mesothelioma and, less so, from asbestosis. Wittenoom crocidolite was used extensively in asbestos-cement products in Western Australia. As a result, the state has recorded a higher malignant-mesothelioma mortality rate than in any other Australian state and in any defined general population in the world. Thus, the legacy of Wittenoom has extended beyond the mine and the town, and is still evident more than 50 years after the closure of the mine.

© The Author(s) 2019; all rights reserved. Published by Oxford University Press on behalf of the International Epidemiological Association.

In plain English

This article reviewed research on people exposed to crocidolite (blue asbestos) from the Wittenoom mine and mill in Western Australia, which closed in 1966. It covered two groups followed through hospital, cancer and death records: 6485 men and 410 women employed by the Australian Blue Asbestos company, and 5042 former town residents. The authors reported that, up to the end of 2014, there had been 373 mesothelioma cases (51 peritoneal) in former workers and 158 (6 peritoneal) in former residents. There had also been 497 and 103 lung cancers respectively. By the end of 2013, 143 worker deaths and 10 resident deaths had been certified as asbestosis. About half the mesotheliomas in former residents occurred in people who were under 15 while at Wittenoom. Earlier studies reviewed found that the mesothelioma rate rose with cumulative exposure, and that asbestos almost multiplied the lung cancer rate from smoking. The authors noted that the residents' exposure estimates had not been directly validated. They concluded that the disaster had been directly responsible for many deaths and ongoing disease, and that the legacy continues.

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: Review of more than 50 years of research on two Wittenoom cohorts (workers and former residents), with updated counts of cancers and deaths presented in a table
• Who was studied: 6485 men and 410 women employed by the Australian Blue Asbestos (ABA) company at Wittenoom, Western Australia, followed since 1982. Also 5042 former Wittenoom township residents (2431 men, 2611 women), not including ABA employees, assembled from public records in 1978.
• Exposure: Virtually exclusive exposure to crocidolite (blue asbestos) from mining and milling at Wittenoom (1943 to 1966) or from living in the town. Workers' cumulative exposure (fibres per millilitre years) was estimated from job grades on a 0 to 10 scale calibrated to a 1966 fibre survey. Residents were assigned 1.0 f/ml from 1943 to 1957 and 0.5 f/ml from 1958 to 1966.
• Main results:
  • Up to the end of 2014 there were 373 mesothelioma cases (51 peritoneal) in former workers and 158 cases (6 peritoneal) in former residents
  • In former residents, about 50% of mesothelioma cases occurred in those who were children (under 15 years) when at Wittenoom
  • Up until December 2014, 497 members of the former workers' cohort and 103 members of the former residents' cohort were known to have developed lung cancer
  • By the end of 2013 there had been 143 known deaths certified as asbestosis in workers and 10 in residents
  • By the end of 2015, 44% of workers and 71% of former residents were still not known to have died
  • An earlier study reviewed (follow-up to end of 2008, workers' cohort) found the mesothelioma rate increased with time from first exposure, levelling off after about 40 to 50 years, and increased with cumulative exposure category
  • Earlier statistical modelling reviewed showed asbestos exposure almost multiplied the rate of lung cancer attributable to smoking alone
  • Former Wittenoom workers and residents still make up nearly 25% of the roughly 100 mesothelioma cases documented each year by the WA Mesothelioma Registry
  • Western Australia had the highest age-standardized mesothelioma incidence in Australia, 4.5 per 100 000 in 2016 (figure from the Mesothelioma in Australia 2016 report)
  • The WA Mesothelioma Registry recorded 39 mesothelioma cases (until 2013) in Aboriginal people exposed through transport of asbestos and contamination in the region
• The authors' conclusion: The authors concluded that the Wittenoom industrial disaster had been directly responsible for many deaths and for ongoing disease and social issues in workers, residents, transport workers and others later exposed, and that the legacy continues.
• Limitations the authors state:
  • The exposure estimates for residents have not been directly validated
  • There are concerns about the monitoring data used to calculate workplace exposures
  • Asbestos fibre counts of work areas were made only once, shortly before the mine closed in 1966
  • Many residents were transient and did not appear in the public records used to build the residents' cohort

Topics

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

Medical terms in this study, explained in our Lexicon: Wittenoom, Crocidolite, Australian Blue Asbestos, Lung Cancer, Malignant Mesothelioma, Asbestos-Cement, Mesothelioma.

Related studies

• Autoimmune antibodies and asbestos exposure: Evidence from Wittenoom, Western Australia — A. Reid, P. Franklin, et al. (2018)
• Malignant mesotheliomas in former miners and millers of crocidolite at Wittenoom (Western Australia) after more than 50 years follow-up — G. Berry, A. Reid, et al. (2012)
• Malignant pleural and peritoneal mesotheliomas in former miners and millers of crocidolite at Wittenoom, Western Australia — G. Berry, N.H. de Klerk, et al. (2004)
• Mortality of former crocidolite (blue asbestos) miners and millers at Wittenoom — A.W. Musk, N.H. de Klerk, et al. (2008)
• Migration and work in postwar Australia: mortality profile comparisons between Australian and Italian workers exposed to blue asbestos at Wittenoom — A. Reid, E. Merler, et al. (2018)
• Familial aggregation of malignant mesothelioma in former workers and residents of Wittenoom, Western Australia — N. de Klerk, H. Alfonso, et al. (2013)

Browse more research in International Journal of Epidemiology, or return to medical research.