Mesothelioma Risk Among Maritime Workers According to Job Title: Data From the Italian Mesothelioma Register (ReNaM)

Our plain-English summary of Mesothelioma Risk Among Maritime Workers According to Job Title: Data From the Italian Mesothelioma Register (ReNaM), by L. Vimercati, D. Cavone, O. Negrisolo, et al (La Medicina del Lavoro, 2023).

The study

• Authors: L. Vimercati, D. Cavone, O. Negrisolo, F. Pentimone, L. De Maria, A. Caputi, S. Sponselli, G. Delvecchio, F. Cafaro, E. Chellini, A. Binazzi, D. Di Marzio, C. Mensi, D. Consonni, E. Migliore, C. Brentisci, A. Martini, C. Negro, F. D'Agostin, I. Grappasonni, C. Pascucci, L. Benfatto, D. Malacarne, V. Casotto, V. Comiati, C. Storchi, L. Mangone, S. Murano, L. Rossin, F. Tallarigo, F. Vitale, M. Verardo, S. Eccher, G. Madeo, T. Staniscia, F. Carrozza, I. Cozzi, E. Romeo, P. Pelullo, M. Labianca, M. Melis, G. Cascone, G.M. Ferri, G. Serio
• Journal: La Medicina del Lavoro
• Published: 2023;114(5):e2023038
• Cited by: 2 articles, as counted by NIH iCite
• Read it: PubMed · Publisher · Free full text

Abstract

The study describes the 466 cases of malignant mesotheliomas (MM) collected by the National Mesothelioma Register (ReNaM) in Italy in the period 1993-2018 relating to subjects with exclusive asbestos exposure in merchant or military navy. The cases among maritime workers represent 1.8% of the total cases with defined exposure registred in the ReNaM, of which 212 cases (45.4%) among merchant maritime workers and 254 cases (54.5%) among navy. The distribution by site of mesothelioma showed 453 (97.2%) MM cases of the pleura, 11 (2.3%) of the peritoneum and 2 (0.4%) of the tunica vaginalis of the testis. With regard to occupational exposure, it was classified as certain in 318 (68.2%) cases, probable in 69 (14.8%) cases and possible in 79 (16.9%) cases. Among the 23 classified jobs, the highest percentages of certain exposures are among naval engineers, motor mechanics, machine captains and sailors. Machine crew accounted for 49.3% of the cases, deck crew for 27.6%. All cases began exposure on board between 1926 and 1988. Seamen were exposed to asbestos while at sea by virtue of living onboard ships and from continual release of asbestos fibers due to the motion of a vessel. Epidemiological surveillance through the ReNaM has allowed us to verify among cases in the maritime, navy and merchant marine sectors, that in the past, subjects were exposed regardless of the ship's department where have provided service therefore all these cases must be considered as occupational diseases.

In plain English

This descriptive study covered 466 malignant mesothelioma cases recorded by Italy's National Mesothelioma Register (ReNaM) in 1993 to 2018 among people exposed to asbestos only in the merchant marine or navy. There were 212 merchant marine and 254 navy cases; all but one were men. Exposure, judged from standardized interviews, was classified qualitatively: certain in 318 cases; the text reports 69 probable and 79 possible, the tables 79 probable and 69 possible. By site, 453 were pleural, 11 peritoneal and 2 of the tunica vaginalis of the testis. Machine crew were 49.3% of cases, deck crew 27.6%. The most frequent jobs were a combined naval engineer, stoker, charcoal burner and tubist group (96), motor mechanics (81), sailors (57) and machine captains (51). Exposure began between 1926 and 1988; mean age at diagnosis was 71.9 years and mean latency 55.6 years. The authors concluded that these workers were exposed regardless of ship department and that all these cases must be considered occupational diseases. They noted qualitative exposure data, unreconstructed merchant ship types, and possible exposure misclassification from overlapping job departments.

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: Descriptive case series of mesothelioma cases from a national epidemiological surveillance register (ReNaM)
• Who was studied: 466 malignant mesothelioma cases registered in Italy, 1993 to 2018, with exposure only in the navy or merchant marine: 212 (45.4%) merchant marine and 254 (54.5%) navy. All were male except one woman in the navy. The cases were 1.8% of all ReNaM cases with defined exposure.
• Exposure: Occupational asbestos exposure only in the maritime sector (navy or merchant marine; fisheries and military arsenals or shipyards excluded). Exposure was classified qualitatively as certain, probable or possible from questionnaire interviews; no quantitative fiber measurements were available. Fiber types were not identified for these cases. Exposure began between 1926 and 1988.
• Main results:
  • By site, among the 466 cases: 453 (97.2%) were pleural, 11 (2.3%) peritoneal and 2 (0.4%) tunica vaginalis of the testis mesothelioma
  • Occupational exposure was classified as certain in 318 (68.2%) of the 466 cases. The text gives probable in 69 (14.8%) and possible in 79 (16.9%). Tables 1 and 2, however, total 79 probable and 69 possible.
  • By task, 49.3% of cases were machine crew and 27.6% deck crew. Among the 230 machine crew cases, 187 (81.3%) had certain exposure.
  • The most frequent jobs among the 466 cases were a combined group of naval engineers, stokers, charcoal burners and tubists (96, 20.6%), motor mechanics (81, 17.3%), sailors (57, 12.2%) and machine captains (51, 10.9%)
  • The authors reported that, among the 23 classified jobs, the highest percentages of certain exposure were among naval engineers, motor mechanics, machine captains and sailors
  • Across all cases, mean age at diagnosis was 71.9 years (SD 9.5, median 76, range 36 to 96). Mean latency from first exposure to diagnosis was 55.6 years (SD 10.5, median 52, range 17 to 82).
  • 315 cases (67.5%) began exposure between 1926 and 1960, and 151 cases (32.4%) between 1961 and 1988
  • By year of diagnosis: 87 cases (18.6%) in 1993 to 2000, 231 (49.5%) in 2001 to 2010 and 148 (31.7%) in 2011 to 2018
  • The 11 peritoneal mesothelioma cases were all male: 5 were exposed in the merchant marine and 6 in the navy, and they included nine naval engineers
• The authors' conclusion: The authors concluded that, in the past, these navy and merchant marine workers were exposed to asbestos regardless of the ship's department in which they served, and that all these cases must be considered occupational diseases
• Limitations the authors state:
  • Exposure data were qualitative, not quantitative; no workplace fiber measurements were available in the ReNaM database
  • The types of merchant ships the cases served on (dry cargo, passenger, tankers, etc.) were not reconstructed
  • Asbestos exposure may have been misclassified because job departments and positions often overlap

Topics

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

Medical terms in this study, explained in our Lexicon: Mesothelioma, Malignant Mesothelioma, Asbestos Exposure, Pleura, Peritoneum, Tunica Vaginalis, Occupational Exposure, Merchant Marine.

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• Asbestos Exposure and Malignant Mesothelioma in Construction Workers-Epidemiological Remarks by the Italian National Mesothelioma Registry (ReNaM) — A. Binazzi, D. Di Marzio, et al. (2021)
• Pleural mesothelioma risk in the construction industry: a case-control study in Italy, 2000-2018 — S. Stella, D. Consonni, et al. (2023)
• Malignant mesothelioma due to non-occupational asbestos exposure from the Italian national surveillance system (ReNaM): epidemiology and public health issues — A. Marinaccio, A. Binazzi, et al. (2015)
• Incidence of extrapleural malignant mesothelioma and asbestos exposure, from the Italian national register — A. Marinaccio, A. Binazzi, et al. (2010)
• Pleural malignant mesothelioma epidemic: incidence, modalities of asbestos exposure and occupations involved from the Italian National Register — A. Marinaccio, A. Binazzi, et al. (2012)

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