Asbestos and other ferruginous bodies: their formation and clinical significance

Our plain-English summary of Asbestos and other ferruginous bodies: their formation and clinical significance, by A.M. Churg, M.L. Warnock (The American Journal of Pathology, 1981).

The study

• Authors: A.M. Churg, M.L. Warnock
• Journal: The American Journal of Pathology
• Published: 1981;102(3):447-56
• Type of article: Review
• Cited by: 137 articles, as counted by NIH iCite
• Read it: PubMed · Free full text
• In J-M's library: Johns-Manville's company medical library held a copy (J-M no. 000729).

Abstract

Analyses of asbestos bodies from the general population have confirmed that these structures, like asbestos bodies from the lungs of asbestos workers, contain an asbestos core. In members of the general population this core is almost always an amphibole, whereas asbestos workers may have bodies formed on either amphibole or chrysotile. Most adults have a few bodies, and increasing numbers are seen in blue collar workers and others who handle small amounts of the fiber, with the highest levels being seen in asbestos workers. In men with minimal or extensive occupational exposure, asbestos bodies are formed on the commercial fibers, amosite and crocidolite, whereas women also form a significant number of bodies on the noncommercial fibers, anthophyllite and tremolite. These findings suggest that women may be exposed to specific asbestos-containing products, eg, cosmetic talc. The commercial fibers found in women and white collar men probably reflect atmospheric pollution with asbestos. At the highest levels of exposure, numbers of asbestos bodies correlate in a general way with the presence of asbestosis, although no precise value has been determined above which asbestosis is always found. In persons with much lower or environmental exposure, there does not appear to be any correlation between numbers of bodies and disease, in particular between numbers of bodies and carcinoma of the lung or gastrointestinal tract. The situation for mesothelioma is uncertain.

In plain English

This was a review article. It reviewed research on asbestos bodies (asbestos fibers coated with iron and protein) and other ferruginous bodies: how they form, what their cores contain, and their link to disease. It also summarized the authors' own earlier studies. In close to 600 bodies from 82 patients who were not asbestos workers, 98% had amphibole cores and 2% had chrysotile cores. In women with fewer than 100 bodies per gram of lung, 12 of 21 cores were anthophyllite or tremolite. In white-collar men and manual laborers, 48 of 57 cores were amosite or crocidolite. The authors found no differences in body counts between 100 lung cancer cases and matched controls, or between 50 gastrointestinal cancer patients and 50 matched controls. The authors concluded that large numbers of bodies may help confirm that asbestos caused a disease such as asbestosis or mesothelioma. In people with little or no history of exposure, there did not appear to be any correlation between body counts and disease; the authors called the situation for mesothelioma uncertain. The numbers needed for confirmation were not yet defined.

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 article, which also summarizes the authors' own earlier laboratory studies
• Who was studied: Published studies of asbestos and ferruginous bodies in the lungs of asbestos workers and of the general population. These include the authors' own earlier autopsy-lung studies of non-asbestos workers, such as close to 600 bodies from 82 patients.
• Exposure: Asbestos fibers forming the cores of bodies: chrysotile and the amphiboles. The amphiboles include the commercial fibers amosite and crocidolite and the noncommercial anthophyllite, tremolite and actinolite. The review also covered non-asbestos cores such as carbon, talc and other sheet silicates.
• Main results:
  • In the authors' studies of non-asbestos workers, 98% of asbestos bodies had amphibole cores and the remaining 2% had chrysotile cores.
  • Combined diffraction and microprobe analysis was done on 81 bodies from 42 patients. Of these, 59 had amosite or crocidolite cores and the remainder had anthophyllite or tremolite cores.
  • In women with fewer than 100 asbestos bodies per gram of lung, 12 of 21 cores (57%) were anthophyllite or tremolite.
  • In white-collar men and manual laborers, cores were predominantly amosite or crocidolite: 48 of 57 (84%).
  • In lung digests from 6 asbestos workers, the authors found 8000 to 500,000 asbestos bodies per gram of wet lung. Counts varied considerably between regions of the same lung.
  • In 100 lung cancer cases from the general population, compared with controls matched for age, sex, smoking habits and occupation, no differences in asbestos body counts were observed.
  • In 50 patients with gastrointestinal cancer compared with 50 matched controls, the authors found no differences in numbers of asbestos bodies in the lungs.
  • The authors stated that the relation between numbers of bodies and mesothelioma at lower or environmental exposure was uncertain.
• The authors' conclusion: The authors concluded that asbestos bodies, when present in large numbers, may serve to confirm the cause in a person with an asbestos-associated disease such as asbestosis or mesothelioma. In persons with little or no history of exposure, there did not appear to be any correlation between numbers of bodies and disease. The authors called the situation for mesothelioma uncertain.
• Limitations the authors state:
  • The number of bodies that suffices to confirm the cause of disease had not yet been defined.
  • Asbestos bodies are only a partial indicator of the asbestos burden in the lung; they appear to reflect mainly long amphibole fibers.
  • There appeared to have been no study of persons with pure chrysotile exposure, so conclusions about bodies as an indicator of total burden are tentative.
  • In the authors' study of smoking and body counts, the number of nonsmokers was small.

Topics

The National Library of Medicine indexes this study under subjects our site covers: Talc and vermiculite.

Medical terms in this study, explained in our Lexicon: Ferruginous Bodies, Asbestos Bodies, Amphibole Group, Chrysotile, Occupational Exposure, Amosite, Crocidolite, Anthophyllite.

Related studies

• Analysis of cores of ferruginous bodies from former asbestos workers — R.F. Dodson, M.F. O'Sullivan, et al. (1982)
• Ferruginous bodies and pulmonary fibrosis in dead low to moderately exposed asbestos cement workers: histological examination — L.G. Johansson, M.P. Albin, et al. (1987)
• Ferruginous bodies as markers of environmental exposure to inorganic particles: experience with 270 autopsy cases in Mexico — F.J. Arenas-Huertero, M. Salazar-Flores, et al. (1994)
• The clinical significance of ferruginous bodies in sputa — J.W. McLarty, S.D. Greenberg, et al. (1980)
• Ferruginous bodies and the histologic evaluation of dust exposure — E. Crouch, A. Churg (1984)
• Fibrous dust particles and ferruginous bodies. Methods for quantitating them and some results from the lungs of city dwellers — P. Gross, J. Tuma, et al. (1970)

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