Occupational Characteristics of Cases with Asbestos-related Diseases in The Netherlands

Ann. occup. Hyg. Occupational Characteristics of Cases with Asbestos- related Diseases in The Netherlands ALEX BURDORF 1 MOHSSINE DAHHAN 1 PAUL SWUSTE 0 0 Safety Science Group, Delft University of Technology , The Netherlands 1 Erasmus MC, University Medical Center Rotterdam, Department of Public Health Objective: To describe the occupational background of cases with an asbestos-related disease and to present overall mesothelioma risks across industries with historical exposure to asbestos. Methods: For the period 1990-2000, cases were collected from records held by two law firms. Information on jobs held, previous employers, activities performed and specific products used were obtained from patients themselves or next of kin. Branches of industry and occupations were coded and the likelihood of asbestos exposure was assessed. For each branch of industry, the overall risk of mesothelioma was calculated from the ratio of the observed number of mesothelioma cases and the cumulative population-at-risk in the period 1947-1960. In order to compare mesothelioma risks across different industries, risk ratios were calculated for the primary asbestos industry and asbestos user industries relative to all other branches of industry. Results: In total, 710 mesotheliomas and 86 asbestosis cases were available. The average latency period was ∼40 yr and the average duration of exposure was 22 yr. Ship building and maintenance contributed the largest number of cases (27%), followed by the construction industry (14%), the insulation industry (12%), and the navy and army, primarily related to ship building and maintenance (5%). In the insulation industry, the overall risk of mesothelioma was 5 out of 100 workers, and in the ship building industry, 1 out of 100 workers. The construction industry had an overall risk comparable with many other asbestos-using industries (7 per 10 000 workers), but due to its size claimed many mesothelioma cases. Conclusion: The majority of cases with asbestos-related diseases had experienced their first asbestos exposure prior to 1960. For cases with first asbestos exposure after 1960, a shift was observed from the primary asbestos industry towards asbestos-using industries, such as construction, petroleum refining, and train building and maintenance. Due to the long latency period, asbestos exposure from 1960 to 1980 will cause a considerable number of mesothelioma cases in the next two decades. mesothelioma; asbestosis; asbestos - INTRODUCTION Asbestos is a well-recognized occupational hazard, affecting primarily the lungs, the pleura and the peritoneum. Numerous epidemiological studies have shown that exposure to asbestos may cause asbestosis, bronchogenic cancer and mesothelioma of the pleura or the peritoneum (Mossman and Gee, 1989). Since asbestos use in Western Europe remained high until 1980, it is expected that the number of men dying from mesothelioma in Western Europe each year will reach a peak of ∼9000 around 2018, and then decline rapidly (Peto et al., 1999). In The Netherlands, a country with one of the highest incidences of mesothelioma, the most plausible scenario predicts an increase in pleural mesothelioma mortality among men from nearly 300 cases in 2000 to ∼490 cases in 2017 and a total death toll close to 12 400 cases during 2000–2028. During the same period, mortality among women will most likely remain low, with 30 cases annually and a total death toll of ∼800 (Segura et al., 2003). Although the dramatic burden of disease due to occupational exposure to asbestos has long been recognized, there is often debate over whether an individual case with an asbestos-related disease can be attributed to a specific source of previous exposure to asbestos. Hence, asbestos exposure during the work history of an individual worker has to be assessed. While the clinical characteristics of asbestosrelated diseases are well described in medical textbooks, there is little information on the quantitative criteria for asbestos exposure in the diagnosis of these diseases. Yet, exposure criteria are important to ensure that asbestos-related diseases are correctly diagnosed and justly compensated (Burdorf and Swuste, 1999). Characteristics of asbestos exposure among individuals with asbestos-related diseases have been described in a few publications (Yeung et al., 1999; Bianchi et al., 2001; Neumann et al., 2001; Yeung and Rogers et al., 2001; Leigh et al., 2002). Important issues that remain largely unknown include duration of asbestos exposure in relation to disease type, duration of latency period, distribution of asbestosrelated diseases over asbestos industries and other branches of industry, and the impact of relatively mild exposure to asbestos. The aim of this paper is to describe the occupational background among cases with asbestos-related diseases in The Netherlands and present information on mesothelioma risks across industries with exposure to asbestos. MATERIALS AND METHOD (...truncated)