Environmental mesothelioma associated with tremolite asbestos: lessons from the experiences of Turkey, Greece, Corsica, New Caledonia and Cyprus

Our plain-English summary of Environmental mesothelioma associated with tremolite asbestos: lessons from the experiences of Turkey, Greece, Corsica, New Caledonia and Cyprus, by S.H. Constantopoulos (Regulatory Toxicology and Pharmacology, 2008).

The study

• Author: S.H. Constantopoulos
• Journal: Regulatory Toxicology and Pharmacology
• Published: 2008;52(1 Suppl):S110-5
• Cited by: 29 articles, as counted by NIH iCite
• Read it: PubMed · Publisher

Abstract

Mediterranean regions such as Greece, Turkey, Cyprus, Corsica and New Caledonia have experienced epidemics of malignant mesothelioma as a result of non-occupational, "domestic" exposure to tremolite asbestos and fibrous erionite. This exposure to tremolite asbestos and fibrous erionite is typified "domestic" due to its prevalence in regions with natural deposits of tremolite asbestos (or fibrous erionite) where the material from tremolite asbestos or fibrous erionite is used for domestic applications such as whitewashing. However, these exposures may be useful in examining the potential consequences of even small amounts of amphibole asbestos fibers in the ambient air. It can also elucidate the effects of fibers that behave like amphibole asbestos. However, this type of exposure is not useful for studying the potential effects of small amounts of asbestos in the ambient air of big cities due to the differing nature of the fiber types and modes of exposure between the regions.

In plain English

This article is a narrative review by a single author. It describes malignant mesothelioma linked to non-occupational exposure to tremolite asbestos and fibrous erionite in Turkey, Greece, Cyprus, Corsica and New Caledonia. It summarized earlier studies, including the author's own group's work in Metsovo. Metsovo is a Greek village of about 5000 people where a tremolite asbestos whitewash called "luto" was used. The review reported that seven mesotheliomas occurred in Metsovo between 1981 and 1985. Between 1986 and 1995, mesothelioma incidence dropped to one-third, after "luto" was abandoned. The review cited a Turkish study from 1980 to 1988 that counted 58 mesothelioma cases linked to erionite and 77 linked to tremolite asbestos, even though the tremolite-exposed population was about twenty times larger. Other cited studies found pleural plaques in 41% of examined residents of Murato, Corsica. In New Caledonia, all but one of fifteen mesotheliomas diagnosed from 1993 to 1995 occurred in Melanesians exposed to a tremolite whitewash. The author concluded that this exposure is better called "domestic" than "environmental". The author also concluded that it cannot serve as an example for small amounts of asbestos in big-city air.

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: Narrative review of earlier published studies (including the author's own group's work) on non-occupational tremolite asbestos and erionite exposure in several regions
• Who was studied: Populations described in earlier studies: villagers in Karain and neighbouring villages, Cappadokia, Turkey (erionite); a larger area of Eastern and Central Anatolia, Turkey (tremolite asbestos); residents of Metsovo, NW Greece (population about 5000) and other villages in the Pindos serpentine zone; mesothelioma cases in Cyprus; residents of Murato and Vezzani, North-East Corsica; and native Melanesians in New Caledonia
• Exposure: Domestic use of tremolite asbestos as whitewash or plaster ("luto" in Metsovo, "Pö" in New Caledonia), and living in cave houses in erionite-containing volcanic rock in Cappadokia. In Metsovo, crushing "luto" released more than 200 fibers per mL; cleaning the floor of an old house released 1 to 4 f/mL; scratching walls released 20 to 40 f/mL.
• Main results:
  • Metsovo (author's group's earlier studies): seven mesotheliomas were reported between 1981 and 1985 in a population of 5000, described as about 300 times higher than expected in a non-asbestos-exposed population
  • Metsovo: mesothelioma incidence between 1986 and 1995 had dropped to one-third, which the author attributed to the abandonment of "luto"
  • Metsovo: about half of the adult population had pleural calcifications in the first study. A repeat study found similar overall incidence but much lower prevalence among younger Metsovites aged 30 to 36.
  • Metsovo: the first five Metsovites with mesothelioma had no plaques. Later studies found that people with plaques had less frequent mesothelioma. The author presented a possible 'protective' response as a hypothesis still being studied.
  • Turkey (cited study, 1980 to 1988): 58 mesothelioma cases were linked to erionite and 77 to tremolite asbestos, although the tremolite-exposed population was around twenty times larger. The author interpreted this as showing erionite is a much more potent agent.
  • Turkey: the male-to-female ratio was 2:1 for tremolite asbestos versus 1:1 for fibrous erionite. A similar ratio was seen in Metsovo.
  • Karain and three neighbouring villages, Cappadokia (cited studies): mesothelioma was the cause of death in half of the inhabitants, corresponding to an incidence 1000 times higher than expected
  • Cyprus (cited study): of 12 confirmed mesotheliomas around 1970 to 1980, five were asbestos miners, three were wives of miners, two lived in nearby villages and two lived in Nicosia. The author stated the offending agent was tremolite asbestos in all cases.
  • Corsica (cited studies): 41% of the examined population of Murato (108 individuals examined) had pleural plaques. 7.5% of people in neighbouring Vezzani had bilateral plaques.
  • New Caledonia (cited case-control study): all but one of the fifteen mesotheliomas diagnosed between 1993 and 1995 occurred in Melanesians exposed to the tremolite whitewash "Pö". Lung cancer risk was also increased significantly among Melanesian women using it.
• The authors' conclusion: The author concluded that this exposure is non-occupational and better called "domestic" than "environmental". The author also concluded that it cannot serve as an example for small amounts of asbestos in big-city air, because the fiber is an amphibole, exposure starts from birth and is at times very high. It could, however, serve to study possible effects of even small amounts of amphibole fibers in ambient air.
• Limitations the authors state:
  • For Metsovo, the author stated it is impossible to tell whether residents inhaled small daily concentrations or huge quantities once or twice a year
  • For Turkey, the author noted no details are available on how the tremolite whitewash was prepared
  • For Cyprus, the author noted that the distance the tremolite cloud from the mine travelled cannot be determined

Topics

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

Medical terms in this study, explained in our Lexicon: Environmental Mesothelioma, Tremolite, New Caledonia, Malignant Mesothelioma, erionite, Amphibole Asbestos.

Related studies

• Rapporteur's Report Session 4: grunerite asbestos (amosite) and tremolite-ferroactinolite asbestos: risk of environmental mesothelioma — J.F. Gamble (2008)
• Environmental exposure to tremolite and respiratory cancer in New Caledonia: a case-control study — D. Luce, I. Bugel, et al. (2000)
• Assessment of environmental and domestic exposure to tremolite in New Caledonia — D. Luce, M.A. Billon-Galland, et al. (2004)
• Environmental airborne tremolite asbestos pollution and pleural plaques in Afghanistan — C. Voisin, I. Marin, et al. (1994)
• Pleural effects of tremolite in north-west Greece — T. Bazas (1987)
• Mesothelioma in Cyprus: the role of tremolite — K. McConnochie, L. Simonato, et al. (1987)

Browse more research in Regulatory Toxicology and Pharmacology, or return to medical research.