Natural fibrous zeolites and their carcinogenicity-a review

Our plain-English summary of Natural fibrous zeolites and their carcinogenicity-a review, by K.R. Spurny (The Science of the Total Environment, 1983).

The study

• Author: K.R. Spurny
• Journal: The Science of the Total Environment
• Published: 1983;30:147-66
• Cited by: 10 articles, as counted by NIH iCite
• Read it: PubMed · Publisher
• In J-M's library: Johns-Manville's company medical library held a copy (J-M no. 003962).

Abstract

More than 50 cases of pleural mesothelioma have been reported during the period 1974-1978 in a relatively small area of Turkey, centered in and around the villages of Karain and Tuzköy, in the province of Cappadocia. The area of Karain and Tuzköy is covered with volcanic tuffs, in which asbestos, glass and zeolite fibers were detected. The inhaled dusts of these fibrous materials might be the cause of the high mesothelioma rate. The most important publications on this problem are reviewed and the results of our own examinations are discussed.

In plain English

This 1983 article reviewed research on pleural mesothelioma in villages of Cappadocia, Turkey, mainly Karain and Tuzköy, where the volcanic tuff contains fibrous zeolites such as erionite. It also reported the author's own examinations, which the author called preliminary and limited. The reviewed studies, by other researchers, described high mesothelioma rates in these villages. Other researchers had also found mixed fibers there, including chrysotile, tremolite and erionite. All seven soil samples the author examined contained mineral fibers. The article calls them Cappadocia samples, but its table lists two sites as Ankara and Yozgat. One sample, from Yozgat, consisted only of fine fibers identified as very probable amphibole asbestos, and fibers in two others were probable zeolites (clinoptilolite). In five ashed pleural tissue samples, most fibers were very probable asbestos and resembled the soil fibers. When injected into the abdominal cavity of rats, the amphibole soil sample showed a relatively high carcinogenic effect compared with erionite from Nevada. The author concluded that the evidence was not at all conclusive that zeolites were the real or single cause of the mesotheliomas, but were one possible explanation.

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 published studies, with the author's own preliminary soil and tissue fiber analyses and a preliminary animal experiment (intraperitoneal injection in rats)
• Who was studied: Own work: seven soil samples that the article describes as from the Cappadocia area, though Table 1 lists sample 5 as from Kalecik Köyü, Ankara and sample 6 as from Sarikaya, Yozgat. Also five pleural tissue samples and rats used in injection experiments. Reviewed work: residents of Cappadocian villages, mainly Karain and Tuzköy, compared with control villages.
• Exposure: Environmental (non-occupational) exposure to fibrous minerals in volcanic tuff and soil. These were fibrous zeolites (erionite, chabazite, mordenite, clinoptilolite) and asbestos (amphibole asbestos; other researchers also reported chrysotile and tremolite). The animal experiment used soil sample 6 (listed in Table 1 as from Yozgat) and erionite from Nevada.
• Main results:
  • Mineral fibers were found in all seven soil samples. One sample (sample 6) contained 100% mostly respirable fibers.
  • The fibers in soil sample 6 were identified as very probable amphibole asbestos.
  • Fibers in soil samples 3 and 7 were estimated to be probable zeolites (clinoptilolite).
  • In the five ashed pleural tissue samples, many fibers were found. In the majority of cases they were identified as very probable asbestos.
  • The fiber type found in the pleural tissue was judged very similar to the fiber types identified in the soil samples.
  • After intraperitoneal injection in rats, soil sample 6 (amphibole asbestos) showed strong carcinogenicity, similar to that for Canadian chrysotile and glass fibers type JM 104. It had a relatively high carcinogenic effect compared with erionite from Nevada.
• The authors' conclusion: The author concluded that the evidence was not at all conclusive that zeolites were the real or single cause of the mesotheliomas in parts of Cappadocia, and that zeolites were one possible explanation. The author also stated that the inhabitants were exposed to a mixed fibrous dust and that more data were needed.
• Limitations the authors state:
  • The author described the investigations as preliminary and limited, and as not sufficient to explain the causes of mesothelioma in Cappadocia.
  • The tissue samples could not be examined with transmission electron microscopy and electron diffraction.
  • The author judged the existing air and drinking-water measurements in Cappadocia to be totally insufficient.

Topics

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

Medical terms in this study, explained in our Lexicon: Zeolite, Pleural Mesothelioma, Karain, Cappadocia, Mesothelioma.

Related studies

• CT findings in malignant pleural mesothelioma related to nonoccupational exposure to asbestos and fibrous zeolite (erionite) — C. Erzen, M. Eryilmaz, et al. (1991)
• Phenotypic characterisation of peripheral blood lymphoid cells in people exposed to fibrous zeolite — M. Ozesmi, A. Karlsson-Parra, et al. (1986)
• Prospective clinical and radiologic study of zeolite-exposed Turkish immigrants in Sweden — M. Ozesmi, G. Hillerdal, et al. (1990)
• Analysis of the biological and chemical reactivity of zeolite-based aluminosilicate fibers and particulates — E. Fach, W.J. Waldman, et al. (2002)
• Malignant mesothelioma induced by asbestos and zeolite in the mouse peritoneal cavity — Y. Suzuki, N. Kohyama (1984)
• The in vitro genetic effects of fibrous erionite and crocidolite asbestos — K.T. Kelsey, E. Yano, et al. (1986)

Browse more research in The Science of the Total Environment, or return to medical research.