Epidemiology of mesothelioma on Walcheren Island.

Stumphius, J. (1971). 28, 59-66. Epidemiology of mesothelioma on Walcheren Island. The chance finding of asbestos bodies without asbestosis' in the lungs of a shipyard worker who had not worked directly with asbestos led to this investigation into the relationship between asbestos bodies in the sputum, occupation, and mesothelioma in the shipyard at Vlissingen on Walcheren Island. Examination of the sputum from a sample of 277 shipyard workers from various occupation groups (excluding insulation workers and others known to work continuously with asbestos) showed asbestos' bodies to be present in 60%. The frequency varied from 39% in workers with no obvious exposure to asbestos dust to 100% among those with slight but definite exposure. By repeating the analysis using the occupations 5 to 10 years previously it was found that many of the workers currently employed in occupations not exposed to asbestos who had asbestos bodies in their sputum had been exposed in the past. Between 1962 and 1968, 25 cases of mesothelioma were discovered on Walcheren; of these, 22 cases had been employed in the shipyard at some time and their actual job was known in all but one case. The shipyard employs approximately 3 000 men so that the attack rate for mesothelioma was approximately 100 per 100 000 males per year. For Dutch provinces with heavy industry the rate is 1·0 per 100 000 per year. For the different occupational categories within the shipyard the rates varied from approximately 50 for `clean work' to 280 for men with some exposure to asbestos dust. Asbestos insulation workers were not included in the study and no cases of mesothelioma came from that occupational group.