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

Background: The study describes the 466 cases of malignant mesotheliomas (MM) collected by the National Meso-thelioma Register (ReNaM) in Italy from 1993-2018 relating to subjects with exclusive asbestos exposure in mer-chant or military navy. Methods: The cases among maritime workers represent 1.8% of the total patients with defined exposure registered in the ReNaM, of which (45.4%) were among merchant maritime workers and 254 cases (54.5%) among the 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. Results: 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, and deck crew for 27.6%. All cases began exposure on board between 1926 and 1988. Seamen were exposed to asbestos while at sea by living onboard ships and from the continual release of asbestos fibers due to the motion of a vessel. Conclusions: Epidemio-logical 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 ships' department where they have provided service; therefore, all these cases must be considered occupational diseases.