On the relative toxicity of asbestos fibres

Our plain-English summary of On the relative toxicity of asbestos fibres, by M. Finkelstein (British Journal of Industrial Medicine, 1985).

The study

• Author: M. Finkelstein
• Journal: British Journal of Industrial Medicine
• Published: 1985;42(1):69-70
• Type of article: Letter
• Cited by: 2 articles, as counted by NIH iCite
• Read it: PubMed · Publisher · Free full text
• In J-M's library: Johns-Manville's company medical library held a copy (J-M no. 001228).

In plain English

This was a letter to the editor, not a new study. The author reanalysed figures published in two earlier papers by A D McDonald and colleagues on workers at two American asbestos textile factories: a South Carolina plant that used chrysotile, and a Pennsylvania factory that used chrysotile, amosite and crocidolite. Because mesothelioma may go undiagnosed, the author counted deaths from all cancers rather than mesothelioma alone. For each dust exposure category, the author divided observed cancer deaths by expected deaths from all causes. The method assumed that cancers unrelated to asbestos stay at roughly 20% of expected deaths. In the lowest category (under 10, in units the table labels mpcfy) this ratio was 0.22 in South Carolina and 0.19 in Pennsylvania. In the highest category (over 80) it was 0.88 and 0.63. Compared with each factory's lowest category, these gave ratios of 4.0 and 3.38. The author stated that the adjusted cancer risk was the same in both factories. The author concluded that the data suggest the risk of death from asbestos-associated cancer in factories making similar products is unrelated to the type of fibre used.

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: Letter to the editor reanalysing published data (tables 5) from two earlier cohort mortality papers by McDonald and colleagues
• Who was studied: Workers in two American asbestos textile factories, one in South Carolina and one in Pennsylvania, as reported in McDonald and colleagues' papers. The letter does not give the number of workers.
• Exposure: Chrysotile only (South Carolina plant) compared with a mixture of chrysotile and the amphiboles, amosite and crocidolite (Pennsylvania factory). Dust exposure was grouped into five categories, from under 10 to over 80 (units labelled mpcfy in the table).
• Main results:
  • The method assumed that cancers unrelated to asbestos stay at roughly 20% of expected all-cause deaths, while asbestos-associated cancers rise with exposure.
  • South Carolina (chrysotile): the ratio of cancer deaths to expected all-cause deaths was 0.22 in the lowest exposure category (73 cancer deaths, 31 respiratory, against 325 expected). It was 0.88 in the highest category (11 cancer deaths, 8 respiratory, against 12.5 expected). Relative to the lowest category, the ratios were 1.22, 1.45, 2.0 and 4.0 across the higher categories.
  • Pennsylvania (chrysotile, amosite, crocidolite): the ratio was 0.19 in the lowest exposure category (94 cancer deaths, 21 respiratory, against 505 expected). It was 0.63 in the highest category (30 cancer deaths, 11 respiratory, against 48 expected). Relative to the lowest category, the ratios were 0.89, 1.34, 1.99 and 3.38 across the higher categories.
  • The author stated that the risk of death from cancer, adjusted for expected all-cause mortality, was the same in both factories.
• The authors' conclusion: The author concluded that the data suggest the risk of death from asbestos-associated cancer in factories manufacturing similar products is unrelated to the type of asbestos fibre used.
• Limitations the authors state:
  • The author noted that undiagnosed cases of mesothelioma remain a problem in these cohorts. This was the reason for using deaths from all malignant disease instead of mesothelioma deaths.

Topics

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

Related studies

• In vitro determinants of asbestos fiber toxicity: effect on the relative toxicity of Libby amphibole in primary human airway epithelial cells — K.E. Duncan, P.M. Cook, et al. (2014)
• Intrapleural administration of fibres induces mesothelioma in rats in the same relative order of hazard as occurs in man after exposure — P. Carthew, R.J. Hill, et al. (1992)
• Bridging the gap between toxicity and carcinogenicity of mineral fibres by connecting the fibre crystal-chemical and physical parameters to the key characteristics of cancer — A.F. Gualtieri (2021)
• Mineral fibre toxicity: expression of retinoblastoma (Rb) and phospho-retinoblastoma (pRb) protein in alveolar epithelial and mesothelial cell lines exposed to fluoro-edenite fibres — G. Musumeci, V. Cardile, et al. (2011)
• The Acute Toxicity of Mineral Fibres: A Systematic In Vitro Study Using Different THP-1 Macrophage Phenotypes — S. Mirata, V. Almonti, et al. (2022)
• Assessment of the toxicity of man-made fibres. A final report of a workshop held in Paris, France 3-4 February 1994 — J. Bignon, P. Brochard, et al. (1995)

Browse more research in British Journal of Industrial Medicine, or return to medical research.