Occupational asbestos exposure among respiratory cancer patients in Lithuania

Our plain-English summary of Occupational asbestos exposure among respiratory cancer patients in Lithuania, by R.P. Everatt, G. Smolianskiene, A. Tossavainen, et al (American Journal of Industrial Medicine, 2007).

The study

• Authors: R.P. Everatt, G. Smolianskiene, A. Tossavainen, S. Cicenas, R. Jankauskas
• Journal: American Journal of Industrial Medicine
• Published: 2007;50(6):455-63
• Cited by: 6 articles, as counted by NIH iCite
• Read it: PubMed · Publisher

Abstract

Background: Despite intensive use of asbestos, no cancer case has ever been diagnosed as asbestos related in Lithuania. This paper attempts to estimate the proportion of those occupationally exposed to asbestos among respiratory cancer patients.

Material And Methods: Occupational exposure to asbestos was assessed retrospectively for 298 lung cancer and four mesothelioma patients, admitted to the Institute of Oncology, Vilnius. The evaluation was based on personal interview data using an internationally established questionnaire covering most likely activities of asbestos exposure at the workplace. Cumulative exposure to asbestos at work was estimated in fiber years. Lung tissue asbestos fiber burden analysis was conducted by scanning transmission electron microscopy on 23 samples.

Results: A cumulative asbestos exposure of > or =25 fiber years was found for 10 lung cancer patients (3.4%). They worked in foundries, construction, installation, shipyard, power plant, railway, asbestos cement, glass and chemical industry. In a further 56 lung cancer patients (18.8%) and for one (25%) mesothelioma patient, a cumulative exposure from 5 to 24.9 fiber years was assessed. Asbestos fibers were detected in 18 cases, the burden ranged from 0.1 to 4.1 million fibers/g dry lung tissue; concentrations exceeding 1 million f/g dry lung tissue were found in four cases. All fibers were chrysotile.

Conclusions: Findings indicate that a fraction (3.4%) of the lung cancer cases could be attributed to heavy occupational exposure to asbestos using the Helsinki criterion of > or =25 fiber years. Therefore, approximately 50 lung cancer cases per year in Lithuania could be asbestos-related compensable occupational diseases.

In plain English

This brief report from Lithuania estimated how many patients with lung cancer or mesothelioma had been exposed to asbestos at work. The authors interviewed 302 patients (298 with lung cancer and four with malignant pleural mesothelioma) at the Institute of Oncology of Vilnius University between November 2003 and May 2005, using a detailed questionnaire about past jobs. Cumulative exposure was estimated in fiber years from German reference values. Of the 298 lung cancer patients, 182 (61.1%) had some occupational exposure. Of those 298, 56 (18.8%) had an estimated 5 to 24.9 fiber years and 10 (3.4%), all men, had 25 fiber years or more. One of the four mesothelioma patients had occupational exposure. In lung tissue from 23 patients, asbestos fibers were found in 18, and no amphiboles were detected. The authors concluded that 3.4% of lung cancer patients had 25 fiber years or more of past exposure. They estimated this could mean approximately 50 potentially compensable lung cancer cases a year in Lithuania. They noted that the exposure estimates were imprecise and that patients came from a limited 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: Brief report: hospital-based series of cancer patients with retrospective, interview-based estimates of occupational asbestos exposure, plus lung tissue fiber analysis in a subset
• Who was studied: 302 patients (298 with lung cancer: 277 men, 21 women; 4 with malignant pleural mesothelioma) hospitalized at the Institute of Oncology of Vilnius University, Lithuania, between November 1, 2003 and May 15, 2005. Lung tissue was analysed for 23 of them (20 lung cancer, 3 mesothelioma), all men.
• Exposure: Lifetime occupational asbestos exposure (asbestos used in Lithuania was mainly chrysotile). It was estimated in fiber years from interview job histories and German expert estimates of fiber concentrations by job (BK-Report 'Faserjahre'). Exposure was grouped as not exposed (under 0.01), 0.01 to 4.9, 5 to 24.9, and 25 or more fiber years.
• Main results:
  • Of the 298 lung cancer patients, 182 (61.1%) had occupational asbestos exposure. 116 (38.9%) were not exposed.
  • 56 of the 298 lung cancer patients (18.8%; 19.5% of men and 9.5% of women) had an estimated cumulative exposure of 5 to 24.9 fiber years.
  • 10 of the 298 lung cancer patients (3.4%) had an estimated cumulative exposure of 25 fiber years or more, and all of them were men.
  • The 10 heavily exposed lung cancer patients had worked in foundries, construction, installation, a shipyard, a power plant, railway, asbestos cement, and the glass and chemical industries.
  • All 10 heavily exposed lung cancer patients were current smokers (70%) or ex-smokers (30%).
  • One of the four malignant pleural mesothelioma patients had occupational asbestos exposure, given in the text as 8.8 fiber years. The other three had estimated exposure below 0.01 fiber years.
  • In lung tissue from 23 patients, asbestos fibers were detected in 18, at concentrations from 0.1 to 4.1 million fibers per gram of dry lung tissue.
  • In 4 of the 23 tissue samples, concentrations were above 1 million fibers per gram of dry lung tissue. No amphiboles were detected in any sample; only chrysotile fibers were found.
  • There was no statistically significant correlation between fiber concentrations in lung tissue and the exposure estimates from job histories.
• The authors' conclusion: The authors concluded that 3.4% of the lung cancer patients had past occupational asbestos exposure of 25 fiber years or more (the Helsinki criterion used in the study). Applied to the more than 1,500 new lung cancer cases diagnosed in Lithuania each year, they estimated this could mean approximately 50 potentially compensable occupational disease cases annually. This was an estimate; the article does not report cases that were actually compensated.
• Limitations the authors state:
  • Exposure was assessed retrospectively without any measurements, because airborne fiber measurements before 1999 are not available in Lithuania.
  • Values from a German database were used, and it is not known whether past Lithuanian exposure conditions matched those in German workplaces.
  • Patients came from a restricted geographic area with few from northern or western Lithuania. The authors said this likely led to an underestimate of cases from the asbestos-cement industry and shipyards.

Topics

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

Medical terms in this study, explained in our Lexicon: Asbestos Exposure, Occupational Exposure, Lung Cancer, Mesothelioma, Cumulative Exposure, Fiber Year, Fiber Burden Analysis, Transmission Electron Microscopy (TEM).

Related studies

• Status of occupational cancer in Lithuania — R. Everatt, R. Jankauskas, et al. (2006)
• Occupational respiratory diseases in the Czech Republic — P. Brhel (2003)
• Non-malignant occupational respiratory diseases in Germany in comparison with those of other countries — X. Baur, U. Latza (2005)
• Pulmonary mineral fibers after occupational and environmental exposure to asbestos in the Russian chrysotile industry — A. Tossavainen, E. Kovalevsky, et al. (2000)
• Pleural plaques in dentists from occupational asbestos exposure: a report of three cases — L. Sichletidis, D. Spyratos, et al. (2009)
• Study of occupational lung cancer in asbestos factories in China — H. Zhu, Z. Wang (1993)

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