Female Textile Workers In Shanghai Research Articles

Colorectal Cancer Incidence Among Female Textile Workers in Shanghai, China: A Case-cohort Analysis of Occupational Exposures

Previous studies have suggested increased risks of colorectal cancers among textile industry workers, potentially related to synthetic fibers. To investigate risks of colon and rectum cancers in relation to these and other textile industry exposures, we conducted a case-cohort study nested within a cohort study of female employees from the Shanghai Textile Industry Bureau (STIB). Cox proportional hazard regression modeling was used to estimate hazard ratios (HR) for colon and rectum cancers associated with duration of employment (e.g., 0, >0 to <10, 10 to <20 years, > or =20 years) in various jobs classified according to process type and exposures to specific agents. Our findings indicate that certain long term exposures may pose increased risk of colorectal cancers, especially dyes and dye intermediates with colon cancer (> or =20 years exposure versus never, HR=3.9; 95% CI: 1.4-10.6), and maintenance occupation (HR = 2.3; 95% CI: 1.0-5.7) and metals exposure (HR = 2.0; 95% CI: 1.1-3.6) with rectum cancer. A decreased risk of rectum cancer was associated with exposure to natural fibers such as cotton (HR = 0.7; 95% CI: 0.5-0.9), and a trend of decreasing rectum cancer incidence was observed by category of cumulative quantitative cotton dust or endotoxin exposures, when exposures were lagged by 20 years.

Reproductive history, occupational exposures, and thyroid cancer risk among women textile workers in Shanghai, China

Thyroid cancer risk has been previously associated with increased age at first pregnancy and history of miscarriage. Occupational risk factors for thyroid cancer, with the exception of radioactive iodine, have not been well investigated. We conducted a case-cohort study nested in a cohort of 267,400 female textile workers in Shanghai, China, who had been followed for cancer incidence during 1989-1998. The analysis included 130 incident thyroid cases and 3,187 subcohort non-cases. Reproductive history was determined by questionnaire at baseline. Historical exposures were reconstructed from work history and information on factory processes and exposures. Cox proportional hazards analysis was performed to estimate hazard ratios (HR) for reproductive factors and occupational exposures. Associations were observed between thyroid cancer and employment in jobs with 10 or more years of benzene exposure (HR 6.43, 95% CI: 1.08, 38) and formaldehyde exposure (HR 8.33, 95% CI: 1.16, 60). Administration workers also had an increased risk (HR 1.56, 95% CI: 1.08, 2.25). No associations between examined reproductive factors and thyroid cancer were observed in this study. Despite statistically imprecise risk estimates, the findings suggest potential associations with some occupational chemical exposures in this cohort of textile workers.

Contraceptive methods and induced abortions and their association with the risk of colon cancer in Shanghai, China

267400 female textile workers in Shanghai, who were administered a questionnaire at enrollment into a randomised trial of breast self-examination between October 1989 and October 1991, were followed up until the middle of 2000. Based on the 655 women who developed colon cancer, rate ratios (RRs) were estimated and trends in risk assessed using Cox Proportional Hazards Models. Risk was increased in women who used oral contraceptives for over 3 years (RR=1.56, 95% Confidence Interval (CI) 1.01–2.40). A possible increase in risk was also observed in women who received progestational injections during pregnancy (RR=1.24, 95% CI 0.95–1.62), but not in relation to the use of injectable contraceptives. A possible reduction in risk was associated with tubal ligation (RR=0.86, 95% CI 0.71–1.03) and ever having had an induced abortion (RR=0.84, 95% CI 0.71–1.00). No trends in risk were observed in relation to the duration of hormonal contraceptive use or the number of induced abortions. Additional studies of the possible roles contraceptives may play in the aetiology of colon cancer in women at low risk of this disease are warranted.

Risk factors for fibroadenoma in a cohort of female textile workers in Shanghai, China.

Risk factors for fibroadenoma were investigated in a cohort of 265,402 female textile workers in Shanghai, China, who were interviewed at enrollment into a randomized trial of breast self-examination between October 1989 and October 1991 and followed until July 2000. Based on 1,507 women who developed fibroadenoma, relative risks and trends in risk were estimated using Cox regression. The risk of fibroadenoma was highest in women under 35 years of age, and it decreased with age after 35 and dropped markedly at the time of menopause. The risk decreased with increasing number of livebirths and with duration of oral contraceptive use. The risk increased with number of prior benign breast lesions and with decreasing age at the first benign lesion. The risk of a diagnosis of fibroadenoma was elevated in women who received instruction in breast self-examination. The development and persistence of fibroadenomas are dependent on the presence of ovarian hormones, and full-term pregnancies and exposure to exogenous estrogen-progesterone combinations before menopause may reduce risk by enhancing differentiation or reducing estrogen-induced proliferation in the mammary epithelium. The practice of breast self-examination detects some fibroadenomas that would otherwise not be detected.