Cytological Analysis of Upper Respiratory Tract Epithelial Cells in Chrysotile Asbestos Factory Workers

Our plain-English summary of Cytological Analysis of Upper Respiratory Tract Epithelial Cells in Chrysotile Asbestos Factory Workers, by Y. Otarov, Z. Zharylkassyn, A. Shaibek, et al (Life, 2025).

The study

• Authors: Y. Otarov, Z. Zharylkassyn, A. Shaibek, M. Mukasheva, Z. Sabirov, A. Alexeyev, A. Izdenov, C. Ismailov, M. Tilemissov, G. Dossybayeva, N. Zhaketayeva, U. Shaikhattarova
• Journal: Life
• Published: 2025;15(3)
• Cited by: 1 article, as counted by NIH iCite
• Read it: PubMed · Publisher · Free full text

Abstract

Objective: This study aims to assess the impact of prolonged occupational exposure to chrysotile asbestos on the epithelial cells of the upper respiratory tract and the levels of surfactant protein D (SP-D) in female workers.

Methods: Buccal epithelial cell samples were collected from 40 workers at JSC "Kostanay Minerals", fixed using the May-Grünwald method, and stained with the Romanowsky-Giemsa technique. SP-D levels were measured using an enzyme-linked immunosorbent assay (ELISA).

Results: Workers exposed to asbestos dust exhibited a significant increase in cytological abnormalities and higher SP-D levels compared to the control group.

Conclusion: Prolonged exposure to chrysotile-containing dust leads to degenerative changes in upper respiratory tract epithelial cells, characterized by cytological and cytogenetic abnormalities, alongside elevated SP-D levels, highlighting the need for preventive health measures.

In plain English

This study compared two groups of 20 female workers, aged 40 to 65, at JSC “Kostanay Minerals”, a chrysotile asbestos enterprise in Zhitikara, Kazakhstan. All had at least 20 years' experience, were non-smokers and showed no clinical signs of disease. Group 1 worked in the enrichment complex, with significant exposure to chrysotile-containing dust; Group 2, in engineering, technical and auxiliary services, had less. Workplace dust was 1.73 mg/m3 for Group 1 and 0.48 mg/m3 for Group 2, neither exceeding the permissible limit. The authors examined cheek cells and measured blood surfactant protein D (SP-D). Compared with Group 2, Group 1 had fewer normal cells (mean 44.10%, confidence interval 38.76–49.43, vs 60%, 56.59–64.70), more cells with karyorrhexis, a breakdown of the nucleus (11.95%, 10.01–13.89, vs 6.55%, 5.44–7.66), and more with micronuclei (1.40%, 0.68–2.12, vs 0.75%, 0.32–1.17). SP-D was 15% higher in Group 1. Several other cell measures did not differ significantly. The authors concluded that women with prolonged chrysotile dust exposure showed degenerative upper airway cell changes. They noted this showed association, not cause, and that alcohol or lifestyle factors might contribute.

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: Comparative study of two groups of workers at one enterprise (more-exposed versus less-exposed), using cheek-cell cytology and a blood test for surfactant protein D
• Who was studied: 40 female workers at JSC “Kostanay Minerals”, Zhitikara, Kostanay region, Kazakhstan. Group 1 was 20 enrichment complex workers (crusher operators, operators of crushing-milling-sorting mechanisms, regulators, ventilation and aspiration operators). Group 2 was 20 engineering-technical and auxiliary service workers (controllers, technologists, supervisors, markers). All had at least 20 years of work experience, were aged 40 to 65, were non-smokers, had lived in Zhitikara since birth, and were free from clinical signs of disease.
• Exposure: Airborne chrysotile-containing dust, measured as respirable dust mass concentration in the breathing zone (no fiber counts reported). Group 1 was 1.73 ± 0.23 mg/m3, 3.6 times higher than Group 2 at 0.48 ± 0.11 mg/m3. Dust in both groups' workplaces did not exceed the maximum permissible concentration.
• Main results:
  • Normal cheek epithelial cells were 44.10 ± 2.55 (%) (CI 38.76–49.43) in Group 1 versus 60 ± 1.93 (CI 56.59–64.70) in Group 2, a 26.5% reduction (p = 0.01 in Table 1).
  • Cells with karyorrhexis were 11.95 ± 0.93 (CI 10.01–13.89) in Group 1 versus 6.55 ± 0.53 (CI 5.44–7.66) in Group 2, an 82% increase (p = 0.01 in Table 1).
  • Cells with phagocytized apoptotic inclusions were 24.00 ± 2.52 in Group 1 versus 16.35 ± 1.47 in Group 2, 46.78% higher (p = 0.01 in Table 1).
  • Cells with micronuclei were 1.40 ± 0.34 (CI 0.68–2.12) in Group 1 versus 0.75 ± 0.20 (CI 0.32–1.17) in Group 2, about twofold (p = 0.04 in Table 1).
  • Microflora contamination was 60.30 ± 5.47 in Group 1 versus 35.25 ± 4.51 in Group 2, 45% higher (p = 0.01 in Table 1).
  • Several cell measures did not differ at p less than 0.05 in Table 1: binucleated cells were 0.65 ± 0.25 in Group 1 versus 0.30 ± 0.15 in Group 2 (p = 0.06); degenerated neutrophils (p = 0.88), cytoplasmic dystrophy (p = 0.53), mast cells (p = 0.93) and multinucleated cells (p = 0.15) also did not differ.
  • Serum SP-D was 4.63 ± 0.18 (4.26–5.01) ng/mL in Group 1 versus 4.03 ± 0.20 (3.59–4.48) ng/mL in Group 2, 15% higher. No p-value is given in the text for this comparison.
  • A regression model linking cell changes to SP-D levels had R2 = 0.17 and accounted for 17.08% of the variability in SP-D levels.
• The authors' conclusion: The authors concluded that externally healthy female workers with prolonged occupational exposure to chrysotile asbestos dust showed degenerative changes in upper respiratory tract epithelial cells (cytological and cytogenetic abnormalities) and increased serum SP-D, and that these results call for enhanced occupational health monitoring and preventive measures.
• Limitations the authors state:
  • Alcohol consumption and other lifestyle factors may contribute to the observed cell abnormalities.
  • The results show an association between asbestos exposure and the cell abnormalities, not a causal relationship.
  • Binucleated cells and nuclear protrusions were too infrequent to draw definitive conclusions about them.
  • Further genetic studies and long-term follow-up are needed to find out whether these changes progress to malignancy.

Topics

Medical terms in this study, explained in our Lexicon: Chrysotile, Occupational Exposure.

Related studies

• Solitary fibrous tumor of the upper respiratory tract. A report of six cases — G.B. Witkin, J. Rosai (1991)
• Immune Status of Workers with Professional Risk of Being Affected by Chrysotile Asbestos in Kazakhstan — S. Koigeldinova, A. Alexeyev, et al. (2022)
• The effects of chrysotile and crocidolite asbestos on the lower respiratory tract: analysis of bronchoalveolar lavage constituents — E. Kagan, Y. Oghiso, et al. (1983)
• Cytological differential diagnosis among adenocarcinoma, epithelial mesothelioma, and reactive mesothelial cells in serous effusions by immunocytochemistry — X.Y. Su, G.D. Li, et al. (2011)
• Serum protein concentrations and respiratory tract abnormalities following short-term exposure to amosite: a comparison between former asbestos workers and unexposed controls — D.R. Nash, N.G. Fortson, et al. (1981)
• An epidemiological study of the role of chrysotile asbestos fibre dimensions in determining respiratory disease risk in exposed workers — L. Stayner, E. Kuempel, et al. (2008)

Browse more research in Life, or return to medical research.