Unexpected excessive chronic obstructive pulmonary disease mortality among female silk textile workers in Shanghai, China

Objective To investigate chronic obstructive pulmonary disease (COPD) mortality among textile workers. Methods A total of 267 400 Chinese female textile employees were monitored for COPD mortality from 1989 to 2000. Textile factories in the cohort were classified into 10 industrial sectors. Age-adjusted mortality, standardized mortality ratios (SMRs) and 95% CIs were calculated by sector. In addition, RRs (HRs) adjusted for smoking and age were calculated for exposure to cotton and silk textile work compared with the other sectors in the cohort. Results A majority of textile sectors had lower or similar COPD mortality (age-adjusted SMRs=0.58–1.15) compared with the general female population in the city of Nanjing, China. SMRs for cotton and silk workers were, respectively, 1.02 (95% CI: 0.81 to 1.28) and 2.03 (95% CI: 1.13 to 3.34). Compared with all other textile sectors in the cohort, there was greater COPD mortality among cotton workers (HR=1.40, 95% CI: 1.03 to 1.89) and silk workers (HR=2.54, 95% CI: 1.47 to 4.39). Conclusion Elevated COPD mortality among cotton workers is consistent with previous reports of adverse respiratory effects of cotton dust. The higher rate of COPD deaths among silk workers was unexpected.