A historical cohort mortality study of workers exposed to asbestos in a refitting shipyard.
To investigate the risks of developing asbestos-related diseases we conducted a historical cohort mortality study on 249 ship repair workers (90 laggers and 159 boiler repairers) in a single U.S. Navy shipyard in Japan. We successfully identified the vital status of 87 (96.7%) laggers and 150 (94.3%) boiler repairers, and, of these, 49 (56.3%) and 65 (43.3%) died, respectively, during the follow-up period from 1947 till the end of 1996. Our in-person interviews with some of the subjects clarified that asbestos exposure was considered to be substantially high in the 1950-60s, decreased thereafter gradually but remained till 1979 in the shipyard. The laggers, who had handled asbestos materials directly, showed a significantly elevated SMR of 2.75 (95% C.I.: 1.08-6.48) for lung cancer. The risk developing the disease was greater in the laggers after a 20-year latency (SMR = 3.42). Pancreatic cancer yielded a greater SMR than unity (7.78, 90% C.I.: 2.07-25.19) in a longer working years group. Four laggers died from asbestosis. The boiler repairers, who had many chances for secondary exposure to asbestos and a few for direct exposure, showed no elevation of the SMR of lung cancer overall, but there was a borderline statistically significant SMR of 2.41 (90% C.I.: 1.05-5.45) in a longer working years group. One boiler repairer died from mesothelioma and four from asbestosis.
Kurumatani
N
N
Department of Public Health, Nara Medical University, Japan.
Natori
Y
Y
Mizutani
R
R
Kumagai
S
S
Haruta
M
M
Miura
H
H
Yonemasu
K
K
D000328:Adult; D000368:Aged; D001194:Asbestos / Q000009:adverse effects*; D001195:Asbestosis / Q000209:etiology / Q000401:mortality; D002423:Cause of Death; D015331:Cohort Studies; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008175:Lung Neoplasms / Q000209:etiology / Q000401:mortality; D008297:Male; D008654:Mesothelioma / Q000209:etiology / Q000401:mortality; D008875:Middle Aged; D009026:Mortality / Q000639:trends*; D016273:Occupational Exposure; D010190:Pancreatic Neoplasms / Q000209:etiology / Q000401:mortality; D012767:Ships
D001194:Asbestos