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Mortality among shipbreaking workers in Taiwan--a retrospective cohort study from 1985 to 2008
Wei-Te Wu1, Yao-Hua Lu, Yu-Jen Lin
1Division of Environmental Health and Occupational Medicine, National Health Research Institutes, Miaoli County, Taiwan.
Background:
Shipbreaking workers are typically exposed to a wide range of hazardous chemicals. However, long-term follow-up studies of their mortality patterns are lacking. This study examined mortality among shipbreaking workers over a 24-year follow-up period.
Methods:
A total of 4,962 shipbreaking workers were recruited from the database of the Kaohsiung Shipbreaking Workers Union. The data were then linked to the Taiwan National Death Registry from 1985 to 2008. The mortality ratios-standardized for age and calendar years-(SMRs) for various causes of deaths were calculated with reference to the general population of Taiwan.
Results:
Among men workers, a statistically significant increased SMR was observed for all causes (SMR = 1.28), all cancers (SMR = 1.26; particularly noteworthy for lesions of oral and nasopharyngeal: SMR 2.03, liver: SMR 4.63, and lung: SMR 1.36), cirrhosis of the liver (SMR = 1.32), and accidents (SMR = 1.91). A statistically significant increase in mortality was observed for respiratory system cancer (SMR = 1.87) and lung cancer (SMR = 1.91) among workers with a longer duration of employment (≥7 years). The result also showed that among shipbreaking workers who were still alive, two people had mesothelioma and 10 people have asbestosis.
Conclusions:
Those employed in shipbreaking industries experienced an increase in mortality from all causes. The increased SMR for lung cancer was probably related to asbestos, metals, and welding fume exposure.
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