Estimated number of cancers attributable to occupational exposures in France in 2017: an update using a new method for improved estimates

Our plain-English summary of Estimated number of cancers attributable to occupational exposures in France in 2017: an update using a new method for improved estimates, by C. Marant Micallef, H. Charvat, M.T. Houot, et al (Journal of Exposure Science & Environmental Epidemiology, 2023).

The study

• Authors: C. Marant Micallef, H. Charvat, M.T. Houot, J. Vignat, K. Straif, A. Paul, M. El Yamani, C. Pilorget, I. Soerjomataram
• Journal: Journal of Exposure Science & Environmental Epidemiology
• Published: 2023;33(1):125-131
• Cited by: 13 articles, as counted by NIH iCite
• Read it: PubMed · Publisher

Abstract

Background: Over the last 50 years, occupational exposure to carcinogenic agents has been widely regulated in France.

Objective: Report population-attributable fraction (PAF) and number of attributable cancer cases linked to occupational exposure in France based on an updated method to estimate lifetime occupational exposure prevalence.

Methods: Population-level prevalence of lifetime exposure to ten carcinogenic agents (asbestos, benzene, chromium VI, diesel engine exhaust, formaldehyde, nickel compounds, polycyclic aromatic hydrocarbons, silica dust, trichloroethylene, wood dust) and two occupational circumstances (painters and rubber industry workers) were estimated using the French Census linked with MATGÉNÉ job-exposure matrices and French occupational surveys. PAF and number of attributable cancer cases were calculated using the estimated prevalence, relative risks from systematic review and national estimates of cancer incidence in 2017.

Results: The lifetime occupational exposure prevalences were much higher in men than in women ranging from 0.2% (workers in the rubber industry) to 10.2% in men (silica), and from 0.10% (benzene, PAH and workers in the rubber industry) to 5.7% in women (formaldehyde). In total, 4,818 cancer cases (men: 4,223; women: 595) were attributable to the ten studied carcinogens and two occupational circumstances, representing 5.2% of cases among the studied cancer sites (M: 7.0%; W: 1.9%). In both sexes, mesothelioma (M: 689 cases; W: 160) and lung cancer (M: 3,032; W: 308) were the largest cancer sites impacted by the studied occupational agents and circumstances.

Significance: A moderate proportion of the cancer cases in France is linked to carcinogens in occupational settings. Our method provides more precise estimates of attributable cancer taking into account evolution of exposure to occupational agents by sex, age and time. This methodology can be easily replicated using cross-sectional occupational data to aid priority making and implementation of prevention strategies in the workplace.

© 2021. The Author(s), under exclusive licence to Springer Nature America, Inc.

In plain English

This modelling study estimated cancers in France in 2017 attributable to workplace exposure to ten carcinogens, including asbestos, and to painter and rubber industry jobs. Exposure estimated from census data, job-exposure matrices and a workplace survey was combined with published relative risks and cancer incidence. For asbestos and mesothelioma, they applied attributable fractions from the French mesothelioma monitoring system to that incidence. An estimated 8.0% of men and 1.2% of women alive in 2017 were exposed to asbestos at work during 1967 to 2007. In men, asbestos was linked to 689 mesotheliomas (95% CI 635 to 743; 83.1% of cases), 1373 lung cancers (862 to 1974) and 42 laryngeal cancers (4 to 86). For women, figures were 160 mesotheliomas (112 to 209; 41.7%), 105 lung cancers (66 to 153), 44 ovarian cancers (22 to 74) and 1 laryngeal cancer (0 to 2). The ten carcinogens and two occupations accounted for 4,223 cases in men (3,580 to 5,008) and 595 in women (496 to 802), 5.2% of cases at studied sites. The authors noted case numbers may be underestimated, notably mesothelioma in men.

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: Population-attributable fraction (burden) estimation study: modelled lifetime exposure prevalence combined with published relative risks and national cancer incidence
• Who was studied: The French population alive in 2017. Exposure was assumed to occur at ages 15 to 64, during 1967 to 2007 for solid cancers. Exposure data came from the census (1982 onward) and the SUMER survey of salaried workers. Incident cancer cases were counted for ages 15 to 84.
• Exposure: Occupational exposure to asbestos (fiber type not specified), benzene, chromium VI, diesel engine exhaust, formaldehyde, nickel compounds, PAH, silica dust, trichloroethylene and wood dust, plus work as a painter or in the rubber industry. Asbestos exposure was assessed by occupation codes linked to the MATGÉNÉ job-exposure matrix.
• Main results:
  • Lifetime prevalence of occupational asbestos exposure was 8.0% in men and 1.2% in women (Tables 2 and 3). This is the share of people alive in 2017 who were exposed during the 1967 to 2007 exposure period.
  • For the asbestos and mesothelioma pair, the authors did not calculate their own attributable fractions. They used those published by the French mesothelioma monitoring system: 83.1% in men and 41.7% in women. They multiplied these fractions by estimated 2017 incidence to obtain attributable case numbers.
  • Men, asbestos and mesothelioma: PAF 83.1% (95% CI 76.6 to 89.6), giving 689 (635 to 743) attributable cases out of 829 incident cases.
  • Men, asbestos and lung cancer: PAF 4.6% (2.9 to 6.6), giving 1373 (862 to 1974) attributable cases out of 30,097. Men, asbestos and larynx cancer: PAF 1.6% (0.2 to 3.2), giving 42 (4 to 86) cases.
  • Women: asbestos accounted for 310 attributable cases in total. These were mesothelioma 160 (112 to 209), with a PAF of 41.7% (29.3 to 54.1); lung 105 (66 to 153); ovary 44 (22 to 74); and larynx 1 (0 to 2).
  • The ten agents and two occupational circumstances together accounted for 4,818 attributable cancer cases: 4,223 in men (95% CI 3,580 to 5,008) and 595 in women (496 to 802). This was 5.2% of new cases at the cancer sites studied (7.0% in men, 1.9% in women).
  • The ten carcinogens alone, excluding the two occupational circumstances, accounted for 3,948 attributable cases, or 4.2% of the cancer cases studied.
  • Lung cancer was the most affected site: 3,032 attributable cases in men (10.1% of male lung cancers) and 308 in women (2.1% of female lung cancers), across all agents studied.
  • Occupational exposures generally declined between 1967 and 2007. For asbestos, the trend changed in 1999.
• The authors' conclusion: The authors concluded that exposure to the studied carcinogens decreased in France over five decades. They concluded that a moderate share of cancers at the studied sites in 2017 was caused by these occupational exposures. They also concluded that their method gives more precise burden estimates because it accounts for sex, age and exposure over time.
• Limitations the authors state:
  • Incident case numbers used only people aged 15 to 84, so attributable cases may be underestimated, for example for mesothelioma and asbestos in men.
  • For chromium VI, nickel, diesel exhaust and PAH, the survey covered only salaried workers and prevalence was not adjusted for non-salaried workers, so those PAFs may be underestimated.
  • Only two or three survey time points were available for some agents, which limited the models used.
  • Some confidence intervals were wide, mainly because of large variances in the relative risks.
  • Each PAF was calculated for a single agent and cancer pair and did not account for co-exposure.
  • Prevalence data on occupational exposure were almost non-existent before the CAREX survey in the 1990s.

Topics

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

Medical terms in this study, explained in our Lexicon: Occupational Exposure, Carcinogenic, Relative Risk, Systematic Review, Mesothelioma, Lung Cancer.

Related studies

• An estimate of cancers attributable to occupational exposures in France — P. Boffetta, P. Autier, et al. (2010)
• Cancers in France in 2015 attributable to occupational exposures — C. Marant Micallef, K.D. Shield, et al. (2019)
• Application of Pattern Mining Methods to Assess Exposures to Multiple Airborne Chemical Agents in Two Large Occupational Exposure Databases from France — J.F. Sauvé, A. Emili, et al. (2022)
• Estimating the social cost of respiratory cancer cases attributable to occupational exposures in France — H. Serrier, H. Sultan-Taieb, et al. (2014)
• Occupational exposures and cancer: a review of agents and relative risk estimates — C. Marant Micallef, K.D. Shield, et al. (2018)
• Choice of rating method for assessing occupational asbestos exposure: study for compensation purposes in France — C. Gramond, P. Rolland, et al. (2012)

Browse more research in Journal of Exposure Science & Environmental Epidemiology, or return to medical research.