Mesothelioma in a worker who spun chrysotile asbestos at home during childhood

Our plain-English summary of Mesothelioma in a worker who spun chrysotile asbestos at home during childhood, by E. Yano, Z.M. Wang, X.R. Wang, et al (American Journal of Industrial Medicine, 2009).

The study

• Authors: E. Yano, Z.M. Wang, X.R. Wang, M.Z. Wang, A. Takata, N. Kohyama, Y. Suzuki
• Journal: American Journal of Industrial Medicine
• Published: 2009;52(4):282-7
• Type of article: Case report
• Cited by: 19 articles, as counted by NIH iCite
• Read it: PubMed · Publisher

Abstract

Background: Malignant mesothelioma has a long latency period and more commonly found in those exposed to amphibole than chrysotile asbestos.

Method: A 35 years old asbestos worker in an asbestos textile plant in Chongqing, China, developed mesothelioma after only 4 years of employment. He was born and bred in a company residence of an asbestos plant and manually spun asbestos thread during school age. In the plant, not amphibole but only chrysotile has been used.

Results: Diagnosis of malignant mesothelioma was confirmed by comprehensive approaches including gross appearance, histology, histochemistry, and immunocytochemistry. In the lung and tumor tissues, huge number of tremolite with exceptional chrysotile was observed despite the reverse proportion in the work environment.

Discussion: Residential exposure and home spinning of asbestos seemed contributed to the early development of mesothelioma in this subject. Although only chrysotile was used and contamination of tremolite was low in the work environment, chrysotile seemed to be cleared leaving tremolite remain in the tissue.

Conclusion: Chrysotile with little contamination of tremolite can lead to early development of malignant mesothelioma when heavily exposed from childhood at a company residence with household exposure. There can be several mechanisms for tremolite to remain in the lung tissue, far exceeding chrysotile in number.

In plain English

This case report described one man who developed malignant mesothelioma after 4 years of work in a chrysotile asbestos textile plant in Chongqing, China. He grew up in company housing. Between ages 14 and 17 he manually spun asbestos thread at home from chrysotile his father brought home, in a small room with the windows closed and no respiratory protection. He fell ill at 35 and died five months after admission to hospital. Tests confirmed a left pleural mesothelioma of epithelial type, and no pleural plaques were seen. Electron microscopy found that the vast majority of asbestos fibers in his lung tissue and in the tumor were tremolite, with few chrysotile fibers. Yet in workplace air sampled years later, tremolite was almost always less than 1% of fibers. Samples from the mines supplying the plant's chrysotile contained less than 0.001% amphibole contamination. The authors suggested that chrysotile may be cleared from the lung faster than tremolite. They concluded that chrysotile with little tremolite contamination can lead to malignant mesothelioma when exposure is heavy.

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 report (one patient), with autopsy, pathology, lung and tumor fiber analysis, and workplace fiber sampling
• Who was studied: One 35-year-old male worker in an asbestos textile plant in Chongqing, China, who fell ill in 1985 after 4 years of employment at the plant; son of an asbestos worker, raised in a company residence
• Exposure: Chrysotile only. He hand-spun asbestos thread at home from about age 14 to 17, in a 10 m2 room with closed windows and no respiratory protection, after growing up in company housing beside the plant. From 18 he worked in a machinery plant with no asbestos, and from age 31 at the asbestos plant, which until recently used only chrysotile from Chinese mines.
• Main results:
  • Gross appearance, histology, histochemistry and immunocytochemistry all supported malignant mesothelioma, left pleural, epithelial cell type
  • No pleural plaques were found at autopsy
  • Mild interstitial fibrosis with an asbestos body was found in the lung
  • In the patient's lung tissue, the vast majority of asbestos fibers were tremolite, with occasional chrysotile fibers
  • The tumor tissue showed a similar fiber pattern: mostly tremolite, very few chrysotile
  • In workplace air sampled in 1998 and 2002, tremolite was almost always less than 1% of fibers, the opposite of the proportions in the lung
  • Workplace fiber concentrations measured in 1998 and 2002, after renovations in the late 1980s, often exceeded 10 fibers/ml
  • Chrysotile samples from the two Sichuan mines that supplied the plant contained less than 0.001% tremolite and other amphibole asbestos
  • The authors suggested that differences in lung clearance between fiber types, among other possible mechanisms, could explain why tremolite exceeded chrysotile in the tissue
• The authors' conclusion: The authors concluded that chrysotile with little tremolite contamination can lead to malignant mesothelioma when exposure is heavy. They also stated that residential exposure and home spinning seemed to have contributed to the early development of the disease in this patient.

Topics

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

Medical terms in this study, explained in our Lexicon: Mesothelioma, Chrysotile, Malignant Mesothelioma, Latency, Amphibole Group, Histology, Tremolite.

Related studies

• Cancer mortality among Chinese chrysotile asbestos textile workers — X.R. Wang, I.T. Yu, et al. (2012)
• Cancer mortality and asbestosis among workers in an asbestos plant in Chongqing, China — F. Zhong, E. Yano, et al. (2008)
• Cause-specific mortality in a Chinese chrysotile textile worker cohort — X. Wang, S. Lin, et al. (2013)
• A 37-year observation of mortality in Chinese chrysotile asbestos workers — X. Wang, E. Yano, et al. (2012)
• Mortality in chrysotile asbestos workers in China — X. Wang, M.N. Courtice, et al. (2013)
• Chrysotile biopersistence in the lungs of persons in the general population and exposed workers — A.M. Langer, R.P. Nolan (1994)

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