Population-Based Cohort Study on Health Effects of Asbestos Exposure in Japan.

Cancer Science 2019 January 7 [Link]

Zha L, Kitamura Y, Kitamura T, Liu R, Shima M, Kurumatani N, Nakaya T, Goji J, Sobue T


Occupational asbestos exposure occurs in many workplaces and is a well-known cause of mesothelioma and lung cancer. However, the association between non-occupational asbestos exposure and those diseases is not clearly described. The aim of this study was to investigate cause-specific mortality among the residents of Amagasaki, a city in Japan with many asbestos factories, and evaluate the potential excess mortality due to established and suspected asbestos-related diseases. The study population consisted of 143,929 residents in Amagasaki City before 1975 until 2002, aged ≥40 years on January 1, 2002. Follow-up was conducted from 2002 to 2015. Standardized mortality ratio (SMR) with its 95% confidence interval (CI) was calculated by sex, using the mortality rate of the Japanese population as reference. A total of 38,546 deaths (including 303 from mesothelioma and 2,683 from lung cancer) were observed. The SMRs in long-term residents’ cohort were as follows: death due to all causes, 1.12 (95% CI, 1.10-1.13) in men and 1.07 (95% CI, 1.06-1.09) in women; lung cancer, 1.28 (95% CI, 1.23-1.34) in men and 1.23 (95% CI, 1.14-1.32) in women; mesothelioma, 6.75 (95% CI, 5.83-7.78) in men and 14.99 (95% CI, 12.34-18.06) in women. These SMRs were significantly higher than expected. The increased SMR of mesothelioma suggests the impact of occupational asbestos exposure among men and non-occupational asbestos exposure among women in long-term residents’ cohort. Besides, high level of excess mortality from mesothelioma persists for a while, despite the mixture of crocidolite and chrysotile no longer being used for three or four decades.