Association of Metsovo lung and pleural mesothelioma with exposure to tremolite-containing whitewash

Our plain-English summary of Association of Metsovo lung and pleural mesothelioma with exposure to tremolite-containing whitewash, by A.M. Langer, R.P. Nolan, S.H. Constantopoulos, et al (Lancet, 1987).

The study

• Authors: A.M. Langer, R.P. Nolan, S.H. Constantopoulos, H.M. Moutsopoulos
• Journal: Lancet
• Published: 1987;1(8539):965-7
• Cited by: 63 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. 000329).

Abstract

Pleural thickening, bilateral pleural hyalinised plaques, and restrictive lung function are found among inhabitants of four small villages in northwestern Greece. Transbronchial biopsy samples from patients with disease contained tremolite fibres. Malignant pleural mesothelioma has now been reported in these villages and accounts for approximately 1% of the total mortality from 1981 to 1985. The principal whitewash once used in this area is predominantly asbestiform tremolite. The fibre is identical in every respect to fibres found in the lung tissues of people with Metsovo lung. The membrane activity of this tremolite is greater than that of the commercially used asbestiform amphiboles amosite and crocidolite. This measure of cytotoxicity lends further support to the hypothesis that this fibre is the agent of Metsovo lung and mesothelioma.

In plain English

This short report examined a whitewash once widely used in homes in four villages in northwestern Greece: Milea, Metsovo, Anilio and Votonosi. Earlier reports had described pleural changes, a condition called "Metsovo lung", and deaths from malignant pleural mesothelioma among the villagers. The authors analysed one specimen of the main local whitewash, a dried mud from a hillside outcropping near Milea. They examined it with light microscopy, X-ray diffraction and electron microscopy, and measured how strongly it destroyed red blood cells in a laboratory test. The whitewash was made up mainly of fine, fibrous, low-iron tremolite, with small amounts of chlorite and a trace of magnesite. After sonication, the length and diameter distributions of the whitewash fibres were statistically identical to those of similarly prepared crocidolite and amosite. Their chemical spectra matched fibres from lung tissue of people with Metsovo lung. In the red-cell test, the tremolite was more damaging than crocidolite and amosite, comparable to quartz, and less damaging than chrysotile. The authors concluded that this tremolite was an excellent candidate agent for the diseases seen. They noted that this whitewash was not the only one used in the area.

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: Laboratory analysis of one whitewash specimen (mineral identification by microscopy and X-ray diffraction, plus a red-cell haemolysis test of cytotoxicity), presented against earlier reports of disease in the villages
• Who was studied: No people were examined in this report. The material studied was a specimen of the principal whitewash of four villages in northwestern Greece (Milea, Metsovo, Anilio, Votonosi). Earlier reports had described pleural disease ('Metsovo lung') and malignant pleural mesothelioma deaths among inhabitants of these villages.
• Exposure: Household whitewash made from local soils, found to be mainly fibrous (asbestiform) tremolite. Before 1940 virtually all inhabitants used such whitewash in their homes. The tremolite was compared in the laboratory with quartz, chrysotile, amosite and crocidolite.
• Main results:
  • Under high magnification, the whitewash grains were aggregates of fine fibres with aspect ratios over 100 to 1, resembling short asbestos fibre
  • X-ray diffraction showed the whitewash was mainly tremolite, with small quantities of chlorite (variety penninite) and a trace of magnesite; the authors concluded it was primarily fine, fibrous tremolite
  • After sonication, the length and diameter distributions of the whitewash fibres were statistically identical to those of similarly prepared crocidolite and amosite
  • The fibre chemistry was that of low-iron tremolite (57% silicon dioxide, 24% magnesium oxide, 14% calcium oxide, 1% ferrous oxide)
  • The chemical spectra of the whitewash fibres were identical to those of fibres seen in lung tissue of people with Metsovo lung
  • In the haemolysis test, the tremolite's cytotoxic potency was greater than that of crocidolite and amosite, comparable to quartz, and less than chrysotile
• The authors' conclusion: The authors concluded that the Metsovo tremolite appears to be an excellent candidate agent for all the diseases observed. They suggested that other populations using locally derived whitewashes may also be at some risk and that this needs study.
• Limitations the authors state:
  • The authors noted that the analysed whitewash is not found everywhere in the area and is not the only whitewash used there

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: Metsovo Lung, Pleural Mesothelioma, Tremolite, Whitewash, Pleural Thickening, Bilateral, Restrictive Lung Disease, Biopsy.

Related studies

• Tremolite whitewashing and pleural calcifications — S.H. Constantopoulos, N.A. Saratzis, et al. (1987)
• Pleural effects of tremolite in north-west Greece — T. Bazas (1987)
• An epidemiological study in an Anatolian village environmentally exposed to tremolite asbestos — Y.I. Baris, N. Bilir, et al. (1988)
• Metsovo-tremolite asbestos fibres: in vitro effects on mutation, chromosome aberration, cell transformation and intercellular communication — K. Athanasiou, S.H. Constantopoulos, et al. (1992)
• Radiological survey of past and present vermiculite miners exposed to tremolite — J.C. McDonald, P. Sebastien, et al. (1986)
• Metsovo lung outside Metsovo. Endemic pleural calcifications in the ophiolite belts of Greece — S.H. Constantopoulos, P. Theodoracopoulos, et al. (1991)

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