Malignant pleural mesothelioma associated with exposure to tremolite

Our plain-English summary of Malignant pleural mesothelioma associated with exposure to tremolite, by D. Luce, P. Brochard, P. Quénel, et al (Lancet, 1994).

The study

• Authors: D. Luce, P. Brochard, P. Quénel, C. Salomon-Nekiriai, P. Goldberg, M.A. Billon-Galland, M. Goldberg
• Journal: Lancet
• Published: 1994;344(8939-8940):1777
• Type of article: Letter
• Cited by: 19 articles, as counted by NIH iCite
• Read it: PubMed · Publisher

Summary of the article

The authors reported preliminary results of an investigation into the high frequency of malignant pleural mesothelioma (MPM) in New Caledonia, which occupational asbestos exposure could not explain. They examined the 28 histologically confirmed MPM cases diagnosed there between 1984 and 1993: 13 men and 15 women, with a mean age at diagnosis of 56.7 years and 3 under 40. Only 2 had been occupationally exposed to asbestos, and 23 were Melanesian (45% of the population). The excess was restricted to some areas, where crude annual incidence could reach 3 cases per 10000 inhabitants. In these areas a friable local rock was used as whitewash for house walls. Analytical transmission electron microscopy showed that rock and whitewash samples consisted primarily of asbestiform tremolite. Air sampling in two villages found no tremolite fibres in the general atmosphere. High concentrations were found in road dust clouds from a car (59 and 669 fibres per L), during whitewash preparation (558 fibres per L), and while whitewashed houses were swept (up to 78000 fibres per L). Tremolite fibres were detected in bronchoalveolar lavage fluid from 2 of 3 MPM cases and in parenchymal tissue from 6 of 8 patients with bronchial cancer. The authors concluded that environmental exposure to tremolite, mainly from the whitewash, is a cause of the high MPM incidence, and said preventive measures were in progress.

PubMed has no abstract for this study, and the article doesn't print one. We wrote this summary from the full article with the help of AI. It is not the authors' wording.

In plain English

This was a short letter giving preliminary results of an investigation in New Caledonia, a French territory in the South Pacific. The authors' earlier work there had found a high frequency of malignant pleural mesothelioma that occupational asbestos exposure could not explain. They examined the 28 histologically confirmed cases diagnosed between 1984 and 1993. There were 13 men and 15 women, and the mean age at diagnosis was 56.7. Only 2 had been exposed to asbestos at work, and 23 of 28 were Melanesian, a group making up 45% of the population. In some areas the crude annual incidence reached 3 cases per 10000 inhabitants. There, a friable local rock was used as whitewash on house walls, and analysis showed it consisted primarily of asbestiform tremolite. Air sampling in two villages found no tremolite in the general atmosphere. High concentrations appeared in road dust clouds raised by a car, during whitewash preparation, and while whitewashed houses were swept (up to 78000 fibres per L). The authors concluded that the results strongly suggest environmental tremolite exposure is a cause of the high incidence, and that use of the whitewash seems to be the main source of exposure.

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: Letter reporting preliminary results of an investigation: a review of mesothelioma cases plus analysis of rock, whitewash, air and patient samples
• Who was studied: 28 histologically confirmed cases of malignant pleural mesothelioma diagnosed between 1984 and 1993 in New Caledonia (13 men, 15 women); airborne sampling in two villages with whitewashed houses
• Exposure: Environmental exposure to asbestiform tremolite in a friable local rock used as whitewash for indoor and outdoor house walls. Melanesians used it extensively from 1930 to the end of the 1960s, and it is still common in the north of the island.
• Main results:
  • Among the 28 cases there were 13 men and 15 women. The mean age at diagnosis was 56.7, and 3 cases were under 40 years of age.
  • Only 2 of the 28 cases had been occupationally exposed to asbestos.
  • 23 of the 28 cases were Melanesian. Melanesians make up 45% of the population.
  • In some areas the crude annual incidence of malignant pleural mesothelioma could reach 3 cases per 10000 inhabitants. The authors described this as 300 times the background incidence of 1 per million person-years.
  • No tremolite fibres were detected in general atmosphere sampling in the two villages.
  • High tremolite fibre concentrations were measured in specific situations: 59 and 669 fibres per L in road dust clouds raised by a car, 558 fibres per L during whitewash preparation, and up to 78000 fibres per L indoors while whitewashed houses were swept.
  • Tremolite fibres were found in bronchoalveolar lavage fluid from 2 of 3 mesothelioma cases. They were also found in lung tissue from 6 of 8 patients with bronchial cancer.
• The authors' conclusion: The authors concluded that the results strongly suggest environmental exposure to tremolite is a cause of the high incidence of malignant pleural mesothelioma in New Caledonia, and that use of the whitewash seems to be the main source of exposure.
• Limitations the authors state:
  • The authors describe the findings as preliminary results.

Topics

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

Medical terms in this study, explained in our Lexicon: Pleural Mesothelioma, Tremolite, New Caledonia, Asbestos Exposure, Friable, Whitewash, Analytical Transmission Electron Microscopy (ATEM), Asbestiform Tremolite.

Related studies

• 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)
• Association of Metsovo lung and pleural mesothelioma with exposure to tremolite-containing whitewash — A.M. Langer, R.P. Nolan, et al. (1987)
• Tremolite whitewashing and pleural calcifications — S.H. Constantopoulos, N.A. Saratzis, et al. (1987)
• Environmental airborne tremolite asbestos pollution and pleural plaques in Afghanistan — C. Voisin, I. Marin, et al. (1994)
• The morbidity and mortality of vermiculite miners and millers exposed to tremolite-actinolite: Part I. Exposure estimates — H.E. Amandus, R. Wheeler, et al. (1987)

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