Elevated micronucleus frequencies in patients with pleural plaque secondary to environmental exposure to asbestos

Our plain-English summary of Elevated micronucleus frequencies in patients with pleural plaque secondary to environmental exposure to asbestos, by M. Gövercin, A.G. Tomatır, F. Evyapan, et al (Genetics and Molecular Research, 2014).

The study

• Authors: M. Gövercin, A.G. Tomatır, F. Evyapan, İ. Acikbas, G. Coşkun, B. Akdag
• Journal: Genetics and Molecular Research
• Published: 2014;13(1):598-604
• Cited by: 8 articles, as counted by NIH iCite
• Read it: PubMed · Publisher

Abstract

We examined genotoxic damage and frequency of micronuclei in people living in the Bekilli and Suller districts of Denizli city who had been diagnosed with pleural plaques as a result of environmental exposure to asbestos. Peripheral blood samples were obtained from 30 volunteer patients 59-86 years old who did not smoke or consume alcohol and who were diagnosed with calcified pleural plaques. We also examined 30 healthy controls with similar features, who also lived in downtown Denizli. Micronucleus frequencies, nuclear division index, and mitotic index were determined. Micronucleus frequency, nuclear division index, and mitotic index were significantly higher in patients who had been exposed to asbestos than in the controls. We conclude that asbestos had a genotoxic effect, resulting in an increase in micronucleus frequency and other changes in patients diagnosed with pleural plaques secondary to asbestos exposure.

In plain English

This study in Denizli, Turkey, compared blood cells from 30 people diagnosed with calcified pleural plaques after environmental asbestos exposure with blood cells from 30 healthy controls. The patients (16 women and 14 men, aged 59 to 86) lived in the Bekilli and Suller districts. The authors described the asbestos there as the tremolite and actinolite (amphibole) type. Controls had the same sex mix and lived in places without asbestos in the soil, but they were younger on average (mean age 53.97 versus 70.83). The authors grew lymphocytes from the blood and counted micronuclei, which they described as an indirect sign of chromosome abnormalities. Mean micronucleus frequency was 4.60 in patients and 0.38 in controls (P = 0.0001). Two measures of cell division were lower in patients: the nuclear division index (1.22 versus 1.36) and the mitotic index (5.80 versus 63.43), both with P = 0.0001. Among patients, micronucleus frequency was not related to age or sex. The authors concluded that the results further demonstrate the genotoxic effect of asbestos. The article's abstract contradicts its own results by calling both division measures higher in patients.

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: cross-sectional laboratory comparison of exposed patients and unexposed controls, using the cytokinesis-block micronucleus (CBMN) assay on cultured blood lymphocytes
• Who was studied: 30 volunteer patients (16 female, 14 male, aged 59-86, mean age 70.83) with calcified pleural plaques, living in the Bekilli and Suller districts of Denizli, Turkey, diagnosed at Pamukkale University's Department of Chest Diseases. 30 healthy controls (16 female, 14 male, aged 37-84, mean age 53.97) living in places without asbestos content in the soil.
• Exposure: Environmental (non-occupational) asbestos exposure from local soil. The authors describe it as the tremolite and actinolite type of the amphibole group. No individual exposure levels were measured.
• Main results:
  • Mean micronucleus (MN) frequency was 4.60 ± 0.15 in the 30 patients and 0.38 ± 0.02 in the 30 controls (mean ± standard error; P = 0.0001).
  • The nuclear division index was lower in patients (1.22 ± 0.01) than in controls (1.36 ± 0.01; P = 0.0001).
  • The mitotic index was lower in patients (5.80 ± 0.45) than in controls (63.43 ± 3.14; P = 0.0001).
  • In 1000 binuclear cells, total nucleoplasmic bridges numbered 153 in patients and 30 in controls, and total nuclear buds numbered 63 in patients and 29 in controls. No statistical test was reported for these counts.
  • Among patients, the authors found no relationship between micronucleus frequency and age or sex. No figures were given.
• The authors' conclusion: The authors concluded that micronucleus frequency was increased, and the nuclear division and mitotic indices decreased, in patients exposed to asbestos, and that these results further demonstrate the genotoxic effect of asbestos.

Topics

The National Library of Medicine indexes this study under subjects our site covers: Pleural plaques and thickening.

Medical terms in this study, explained in our Lexicon: Pleural Plaques, Environmental Exposure, Micronuclei, Mitotic Index, Asbestos Exposure.

Related studies

• Investigation of micronucleus frequencies in lymphocytes of inhabitants environmentally exposed to chrysotile asbestos — H. Dönmez-Altuntas, M. Baran, et al. (2007)
• Environmental asbestos-related pleural plaque in southeast of Turkey — G. Ates, T. Yildiz, et al. (2010)
• Environmental airborne tremolite asbestos pollution and pleural plaques in Afghanistan — C. Voisin, I. Marin, et al. (1994)
• Diachronic study of pleural plaques in rural population with environmental exposure to asbestos — L. Sichletidis, D. Chloros, et al. (2006)
• CT Characteristics of Pleural Plaques Related to Occupational or Environmental Asbestos Exposure from South Korean Asbestos Mines — Y. Kim, J.P. Myong, et al. (2015)
• Validity of the Lymphocyte Cytokinesis-Block Micronucleus Assay (L-CBMN) as biomarker for human exposure to chemicals with different modes of action: A synthesis of systematic reviews — M. Kirsch-Volders, M. Fenech, et al. (2018)

Browse return to medical research.