Cause-specific mortality among workers in asbestos mining and enrichment factories (Asbest Chrysotile Cohort Study) compared with the general population of Sverdlovsk Oblast, Russian Federation

Objectives. Complementing the previously published cohort-internal comparison we hereby compare the cause-specific mortality in workers of the Asbest Chrysotile Cohort study (ACC) with the general population of Sverdlovsk Oblast where the mine and factories are located.

Methods. The ACC cohort database and the regional Federal State Statistic Service for the Sverdlovsk Oblast population were used. We calculated sex-specific standardized mortality ratios (SMRs) and 95% confidence intervals (CI) for the main ICD-10 disease groups and for selected cancer sites for the populations ≥15 years from 1980 to 2015. In relation to exposure, we applied the Sverdlovsk rates to the person-years in each exposure category to obtain expected numbers of lung cancer deaths. For comparing types of ACC workers (mine, enrichment factories, both), we calculated lung cancer SMRs in men by duration of employment (< 5 years, 5–14 years, and ≥ 15 years) and start of employment (before or after 1975) with miners as reference in each stratum.

Results. Overall mortality of men in the ACC was reduced by 14%, mainly because of the most common cause of death, circulatory disease; this effect was much weaker in women. Elevated mortality was observed for both sexes from diseases of the digestive system (10–30%) and blood and blood forming organs (121–181%). Lung cancer mortality in men was increased from the 3^rd quartile of chrysotile containing dust and in the highest quartile with SMR 1.30, 95% CI 1.07–1.57, while the increase in high exposed women was not reaching statistical significance (SMR 1.69, 95% CI 0.87–2.96). No increased SMRs were seen for laryngeal, stomach or ovarian cancers. Male factory workers first employed before 1975 had higher lung cancer mortality compared to miners, but not when employed after 1974.

Conclusions. The observed excess in lung cancer confirms previous observations in the ACC. Risk management measures in the enrichment factories may have reduced the lung cancer risk to the level of the miners in recent decades.

Ethics. The ACC was approved by the International Agency for Research on Cancer (IARC/WHO) Ethics Committee (IEC No. 12–22, September 2012).

Contributions:
Ann Olsson — preparation of the manuscript, project administration, data processing, including quality control, interpretation of the received data;
Joachim Schüz — manuscript preparation, cohort formation, project administration, formal analysis, interpretation of the data obtained;
Hans Kromhout — preparation of the manuscript, evaluation of the exposition;
Evgeny Kovalevskiy — manuscript preparation, cohort formation, project administration, data processing, including quality control, interpretation of the received data;
Monika Moissonnier — preparation of tables and figures, data processing, including quality control, and formal analysis;
Igor Bukhtiyarov — cohort formation, project administration, and data interpretation;
Kurt Straif — cohort formation;
Eleonora Feletto — conducting an exposure assessment, data processing, including quality control, and conducting a formal analysis;
Iraklii Tskhomariia — project administration, data processing, including quality control, and data interpretation;
Tatiana Morozova — project administration and data interpretation;
Evgenia Ostroumova — data processing, including quality control and data interpretation;
Gilles Ferro — data processing, including quality control, formal analysis;
Graham Byrnes — conducting a formal analysis.

Acknowledgements. Dr Sergey Kashanskiy from the Yekaterinburg Medical Research Center for Prophylaxis and Health Protection in Industrial Workers, Yekaterinburg, Russian Federation was instrumental in the conduct of the study but died on February 9, 2023 and is deeply missed by the entire study team. We acknowledge the data entry team in Asbest town who rigorously entered written information into electronic format: the late Isolina Smirnova, Zoya Lapuhina, and Yulia Nurdinova; and Dr Sara J. Schonfeld for her valuable contribution to the ACC overall and the re-coding of the oblast data from ICD-9 to ICD-10. The authors also wish to acknowledge the independent Scientific Advisory Board (SAB). The scientific advisory board members provided their reviews of this manuscript, but the integration of their comments remained at the discretion of the authors.

Funding. The work was supported by the Ministry of Health of the Russian Federation in the framework of the Federal target program "National System of Chemical and Biological Safety of the Russian Federation" of 2009–2014 and of 2015–2020 under a general framework of action between the Federal state budgetary scientific institution “Izmerov Research Institute of Occupational Health” (IRIOH) and the International Agency for Research on Cancer (IARC).

Conflict of interest. Dr Kovalevskiy reported receiving, on behalf of their institutes and personally through consulting firms, payments from companies to evaluate exposure to asbestos and risk of asbestos-related disease in those workplaces. All other authors have no competing interests to declare. For full transparency, Dr Kovalevskiy reported participation as an occupational and environmental health expert as part of the delegation of the Russian Ministry of Health at multiple World Health Assembly meetings as well as at the Conference of the Parties to the Basel and Rotterdam Conventions. Dr Kovalevskiy reported attending meetings organized by the International Chrysotile Association and reported that all expenses for attendance were paid by their respective institutes.

Disclaimer. Where authors are identified as personnel of IARC/WHO, the authors alone are responsible for the views expressed in this article, and they do not necessarily represent the decisions, policy, or views of IARC/WHO.

Data availability. Raw data cannot be made publicly available according to the data confidentiality legislation of the Russian Federation.

A note from the publisher of the original article. Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Received: 08.12.2025 / Accepted: 23.12.2025 / Published: 15.02.2026

1. Federation Council of the Federal Assembly of the Russian Federation. Sverdlovsk Region. 2024. http://www.council.gov.ru/en/structure/r egions/SVE/

2. Schuz J., Schonfeld S.J., Kromhout H., Straif K., Kashanskiy S.V., Kovalevskiy E.V. et al. A retrospective cohort study of cancer mortality in employees of a Russian Chrysotile asbestos mine and mills: study rationale and key features. Cancer Epidemiol. 2013; 37(4): 440–445. https://doi.org/10.1016/j.canep.2013.03.001

3. Schüz J., Kovalevskiy E., Olsson A., Moissonnier M., Ostroumova E., Ferro G. et al. Cancer mortality in chrysotile miners and millers, Russian Federation: main results (Asbest Chrysotile Cohort-Study). J. Natl. Cancer Inst. 2024; 116(6): 866–875. https://doi.org/10.1093/jnci/djad262

4. Notzon F.C., Komarov Y.M., Ermakov S.P., Sempos C.T., Marks J.S., Sempos E.V. Causes of declining life expectancy in Russia. JAMA. 1998; 279(10): 793–800. https://doi.org/10.1001/jama.279.10.793

5. Shkolnikov V., McKee M., Leon D.A. Changes in life expectancy in Russia in the mid-1990s. Lancet. 2001; 357(9260): 917–921. https://doi.org/10.1016/S0140-6736(00)04212-4

6. Russian Federation. Federal Law. On Labor Pensions in the Russian Federation dated 17.12.2001 No. 173-FZ (last edition). Article 27. Preservation of the right to early assignment of a retirement pension. 2001. https://www.consultant.ru/document/cons_doc_LAW_34443/97741a2c98499d0f906c704a67ec5bc92dae1bb1/ (in Russian).

7. Wang X., Yano E., Lin S., Yu I.T., Lan Y., Tse L.A., et al. Cancer mortality in Chinese Chrysotile asbestos miners: exposure-response relationships. PLoS ONE. 2013; 8(8): e71899. https://doi.org/10.1371/journal.pone.0071899

8. Ferrante D., Angelini A., Barbiero F., Barbone F., Bauleo L., Binazzi A., et al. Cause specific mortality in an Italian pool of asbestos workers cohorts. Am. J. Ind. Med. 2024; 67(1): 31–43. https://doi.org/10.1002/ajim.23546

9. Möhner M. An approach to adjust standardized mortality ratios for competing cause of death in cohort studies. Int Arch Occup Environ Health. 2016; 89(4): 593–8. https://doi.org/10.1007/s00420-015-1097-z

10. Feletto E., Kovalevskiy E.V., Schonfeld S.J., Moissonnier M., Olsson A., Kashanskiy S.V., et al. Developing a company-specific job exposure matrix for the Asbest Chrysotile cohort study. Occup. Environ. Med. 2022; 79(5): 339–46. https://doi.org/10.1136/oemed-2021-107438

11. Schüz J., Bukhtiyarov I., Olsson A., Moissonnier M., Ostroumova E., Feletto E., et al. Occupational cohort study of current and former workers exposed to Chrysotile in mine and processing facilities in Asbest, the Russian Federation: cohort profile of the Asbest Chrysotile cohort study. PLoS ONE. 2020; 15(7): e0236475. https://doi.org/10.1371/journal.pone.0236475

12. Schüz J., Kovalevskiy E., Moissonnier M., Olsson A., Hashim D., Kromhout H. et al. Comparison of two information sources for Cause-of-Death Follow-up in the Russian federation: the Asbest Chrysotile cohort study. Methods Inf Med. 2020; 59(1): 9–17. https://doi.org/10.1055/s-0040-1710381

13. Men T., Brennan P., Boffetta P., Zaridze D. Russian mortality trends for 1991–2001: analysis by cause and region. BMJ. 2003; 327(7421): 964. https://doi.org/10.1136/bmj.327.7421.964

14. Kovalevskiy E.V., Schonfeld S.J., Feletto E., Moissonnier M., Kashanskiy S.V., Bukhtiyarov I.V. et al. Comparison of mortality in Asbest City and the Sverdlovsk region in the Russian federation: 1997–2010. Environ. Health. 2016; 15: 42. https://doi.org/10.1186/s12940-016-0125-0

15. Sichletidis L., Chloros D., Spyratos D., Haidich A.B., Fourkiotou I., Kakoura M., et al. Mortality from occupational exposure to relatively pure chrysotile: a 39-year study. Respiration. 2009; 78(1): 63–68. https://doi.org/10.1159/000163443

16. Pira E., Pelucchi C., Piolatto P.G., Negri E., Bilei T., La Vecchia C. Mortality from cancer and other causes in the Balangero cohort of Chrysotile asbestos miners. Occup. Environ. Med. 2009; 66(12): 805–809. https://doi.org/10.1136/oem.2008.044693

17. Rubino G.F., Piolatto G., Newhouse M.L., Scansetti G., Aresini G.A., Murray R. Mortality of Chrysotile asbestos workers at the Balangero Mine, Northern Italy. Br. J. Ind. Med. 1979; 36(3): 187–194. https://doi.org/10.1136/oem.36.3.187

18. Ludwig H., Müldür E., Endler G., Hübl W. Prevalence of iron deficiency across different tumors and its association with poor performance status, disease status and anemia. Ann. Oncol. 2013; 24(7): 1886–1892.

19. Joyce E., Glasner P., Ranganathan S., Swiatecka-Urban A. Tubulointerstitial nephritis: diagnosis, treatment, and monitoring. Pediatr Nephrol. 2017; 32(4): 577–87. https://doi.org/10.1093/annonc/mdt118

20. Liddell F.D., McDonald A.D., McDonald J.C. The 1891–1920 birth cohort of Quebec Chrysotile miners and millers: development from 1904 and mortality to 1992. Ann. Occup. Hyg. 1997; 41(1): 13–36. https://doi.org/10.1093/annhyg/41.1.13

21. Ferrante D., Mirabelli D., Silvestri S., Azzolina D., Giovannini A., Tribaudino P., et al. Mortality and mesothelioma incidence among Chrysotile asbestos miners in Balangero, Italy: A cohort study. Am J Ind Med. 2020; 63(2): 135–145. https://doi.org/10.1002/ajim.23071

22. Olsson A.C., Vermeulen R., Schuz J., Kromhout H., Pesch B., Peters S., et al. Exposure-Response analyses of asbestos and lung cancer subtypes in a pooled analysis of Case-Control studies. Epidemiology. 2017; 28(2): 288–299. https://doi.org/10.1097/EDE.0000000000000604

23. Olsson A., Kovalevskiy E.V., Talibov M., Moissonnier M. et al. Tobacco smoking among Chrysotile asbestos workers in Asbest in the Russian Federation. Occup. Environ Med. 2020; 77(9): 623–627. https://doi.org/10.1136/oemed-2019-106263