OEMED62034 883..887

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 SMRs1⁄40.58e1.15) 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 (HR1⁄41.40, 95% CI: 1.03 to 1.89) and silk workers (HR1⁄42.54, 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. INTRODUCTION Chronic obstructive pulmonary disease (COPD) is a diverse group of lung disorders whose hallmark is airflow obstruction that impedes normal respiration. According to the latest available WHO estimates (2008), 210 million people worldwide have COPD and 3 million people died from COPD in 2005. WHO predicts that COPD will become the third leading cause of death worldwide by 2030. COPD remains a leading cause of death, illness and disability in the USA and the prevalence of COPD is 8.2% in people 40 years of age or older in China. The primary known cause of COPD is exposure to tobacco smoke; however, air pollutants in the working environment may also increase the risk. Numerous previous studies indicate that cotton textile workers have a higher prevalence of respiratory symptoms and greater decline in lung function comparedwith the general population and compared with other textile workers, specifically, man-made fibre and silk workers. 6 Historically, it was believed that byssinosis, whether acute or chronic, could be associated with some impairment of ventilatory capacity, but the overall decline in lung function was small. However, emerging evidence indicates that cumulative exposure to cotton dust may cause a chronic decline in lung function, potentially resulting in COPD. 9 The main occupational exposures of concern are cotton dust and endotoxin in the dust and both were found to be related to the decrease in FEV1. 11 Other potential respiratory hazards in the textile industry include wool dust, silk dust, synthetic fibres, finishing agents, bleaches and highly acidic or basic chemicals. To characterise the remaining uncertainty of risks for COPD among textile workers, we conducted a mortality study among a large cohort of female textile workers in Shanghai, China. The study was approved by the Institutional Review Boards of the University of Washington, the Fred Hutchinson Cancer Research Center in Seattle, WA and Zhong Shan Hospital in Shanghai.