Anthophyllite asbestos: state of the science review

Our plain-English summary of Anthophyllite asbestos: state of the science review, by S.H. Gaffney, M. Grespin, L. Garnick, et al (Journal of Applied Toxicology, 2017).

The study

• Authors: S.H. Gaffney, M. Grespin, L. Garnick, D.A. Drechsel, R. Hazan, D.J. Paustenbach, B.D. Simmons
• Journal: Journal of Applied Toxicology
• Published: 2017;37(1):38-49
• Type of article: Review
• Cited by: 11 articles, as counted by NIH iCite
• Read it: PubMed · Publisher

Abstract

Anthophyllite is an amphibole form of asbestos historically used in only a limited number of products. No published resource currently exists that offers a complete overview of anthophyllite toxicity or of its effects on exposed human populations. We performed a review focusing on how anthophyllite toxicity was understood over time by conducting a comprehensive search of publicly available documents that discussed the use, mining, properties, toxicity, exposure and potential health effects of anthophyllite. Over 200 documents were identified; 114 contained relevant and useful information which we present chronologically in this assessment. Our analysis confirms that anthophyllite toxicity has not been well studied compared to other asbestos types. We found that toxicology studies in animals from the 1970s onward have indicated that, at sufficient doses, anthophyllite can cause asbestosis, lung cancer and mesothelioma. Studies of Finnish anthophyllite miners, conducted in the 1970s, found an increased incidence of asbestosis and lung cancer, but not mesothelioma. Not until the mid-1990s was an epidemiological link with mesothelioma in humans observed. Its presence in talc has been of recent significance in relation to potential asbestos exposure through the use of talc-containing products. Characterizing the health risks of anthophyllite is difficult, and distinguishing between its asbestiform and non-asbestiform mineral form is essential from both a toxicological and regulatory perspective. Anthophyllite toxicity has generally been assumed to be similar to other amphiboles from a regulatory standpoint, but some notable exceptions exist. In order to reach a more clear understanding of anthophyllite toxicity, significant additional study is needed. Copyright © 2016 John Wiley & Sons, Ltd.

Copyright © 2016 John Wiley & Sons, Ltd.

In plain English

This article was a literature review. The authors searched PubMed, ToxNet, Web of Science and textbooks for documents about anthophyllite, an amphibole form of asbestos. They identified 236 potentially relevant publications, included 114, and described them by time period. A reviewed 1974 study of 1092 Finnish anthophyllite miners and millers found excess deaths from lung cancer and asbestosis but no mesotheliomas. A 1994 study found four mesothelioma cases (three pleural, one peritoneal) among 999 Finnish anthophyllite miners and millers. Another 1994 study reported a standardized incidence ratio of 67 (95% CI 18 to 172) for mesothelioma in heavily exposed men who had worked at least 3 months, compared with the eastern Finland general population. In one reviewed rat study, inhaled anthophyllite at sufficient concentration and duration induced asbestosis, mesothelioma and other lung tumors. A 2014 rat injection study found no mesothelioma from anthophyllite. The authors concluded that anthophyllite has not been well studied compared to other forms of asbestos and needs additional study. They noted that the review excluded non-English papers lacking translations, and that lung burden analyses have many limitations.

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: Literature review (state of the science review) of publicly available documents on anthophyllite, presented chronologically by time period
• Who was studied: Published toxicology, epidemiology, occupational and medical publications and other documents found through PubMed, ToxNet, Web of Science and textbooks. 236 were initially identified and 114 were included. The reviewed studies covered mainly Finnish anthophyllite miners and millers, New York talc workers, lung burden case series, and laboratory animals.
• Exposure: Anthophyllite (asbestiform and non-asbestiform), including anthophyllite in mining (notably the Paakkila mine, Finland) and as a contaminant of talc
• Main results:
  • Reviewed study (Meurman et al., 1974): among 1092 Finnish anthophyllite miners and millers, there was excess mortality from lung cancer and asbestosis, and no mesotheliomas were found
  • Reviewed study (Meurman et al., 1979): the relative risk of lung cancer was 3.3 in heavily exposed workers (P less than 0.001). In low to moderately exposed workers it was 1.4; the study did not comment on whether that figure was significant.
  • Reviewed study (Karjalainen et al., 1994): four cases of mesothelioma (three pleural, one peritoneal) occurred in a cohort of 999 Finnish anthophyllite miners and millers at the Paakkila mine. Mesothelioma accounted for about 0.8% of all male deaths. That study did not report a risk estimate; another author later calculated a standardized incidence ratio of 40 (95% CI 10.90 to 102.42).
  • Reviewed study (Meurman et al., 1994): men in the heavily exposed group who had worked for at least 3 months had a standardized incidence ratio of 67 (95% CI 18 to 172) for mesothelioma, compared with the eastern Finland general population. No mesothelioma cases were reported in the moderately exposed group.
  • Reviewed study (Meurman et al., 1994): lung cancer standardized incidence ratios were 3.2 (95% CI 2.4 to 4.1) in heavily exposed men and 2.3 (95% CI 1.5 to 3.6) in moderately exposed men
  • Reviewed studies of New York talc miners and millers (Kleinfeld et al.): deaths from lung and pleural malignancies were 11 observed versus 3.2 expected (1967) and 12 observed versus 3.7 expected (1974). Smoking data were lacking.
  • Reviewed animal study (Wagner et al., 1974): asbestosis, mesothelioma and other lung tumors could be induced in Wistar rats by inhalation of anthophyllite fibers at sufficient concentration and duration
  • Reviewed animal study (Smith and Hubert, 1974): 6% of hamsters given a single intrapleural dose of 10 mg UICC anthophyllite developed mesotheliomas; that study tested no other doses
  • Reviewed animal study (Aierken et al., 2014): anthophyllite injected into the abdominal cavity of rats at 0.5 or 5 mg induced no malignant mesothelioma after 550 days. Tremolite induced malignant mesothelioma in 96% of rats at the highest dose.
• The authors' conclusion: The authors concluded that anthophyllite asbestos, including its potency and other toxicological properties, has not been well studied compared to other forms of asbestos, and that it is worthy of additional study
• Limitations the authors state:
  • The review was limited to English-language literature unless translations were available; fourteen non-English papers without readily available translations were excluded
  • Many reviewed studies used lung burden analyses in place of exposure measurements. Lung burden results give no information on the duration, frequency or intensity of exposure.
  • A detailed discussion of mineralogy and analytical methods for anthophyllite asbestos in talc was outside the review's scope

Topics

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

Medical terms in this study, explained in our Lexicon: Anthophyllite, Amphibole Group, Lung Cancer, Mesothelioma, Talc, Asbestos Exposure, Asbestiform, Non-Asbestiform.

Related studies

• Re: Malignant mesothelioma from neighborhood exposure to anthophyllite asbestos — M. Kottek, D. Kilpatrick (2002)
• Incidence of cancer among anthophyllite asbestos miners in Finland — L.O. Meurman, E. Pukkala, et al. (1994)
• Four cases of mesothelioma among Finnish anthophyllite miners — A. Karjalainen, L.O. Meurman, et al. (1994)
• State-of-the-science assessment of non-asbestos amphibole exposure: is there a cancer risk? — C. Williams, L. Dell, et al. (2013)
• Trees as reservoirs for amphibole fibers in Libby, Montana — T.J. Ward, T. Spear, et al. (2006)
• High frequency and severity of pleural changes in former workers exposed to anthophyllite associated with other contaminating amphibole asbestos in Brazil — R.F. Macedo, E.M.F.P. Cerqueira, et al. (2019)

Browse more research in Journal of Applied Toxicology, or return to medical research.