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Saturday 20, November, 2004 13:30 - 15:30, No.2 Conference Room Workshop E Epidemiology and Public Health Chairs: Gunnar Hillerdal and Kohki Inai Survey on the Mortality of Malignant Tumors in Asbestos Manual Spinning Female Workers Xing Zhang1, Tond-da Sun 2, Nan-feng Shi2, Kenji Morinaga3 1 Institute of Hygiene, Zhejiang Academy of Medical Sciences, P.R.China [not- attended, paper submission] 2 Zhejiang Cixi city sanitation and epidemic prevention station, P.R.China 3 Department of Hazard Assessment, National Institute of Industrial Health, Japan ABSTRACT Introduction: Cixi city is famous for its textile industry. It had developed asbestos processing industry in the 1960s and declined at the beginning of 1990s. The manner of asbestos processing was manual spinning, which was done by female workers in their home. Around 30,000 female workers were directly exposed to asbestos while more than 100,000 relatives were indirectly exposed to asbestos. Objectives: To estimate the prevalence of pleural plaque, asbestosis and the incidence of malignant tumor in asbestos manual spinning female workers. Methods: The mortality of malignant tumors among female workers was investigated by a retrospective cohort study and calculated based on the person-year at risk of the observed group by the life-table method. The standardized mortality ratio (SMR), the relative risk (RR), attributive risk (AR) and their corresponding 95% confidence intervals (Cls) were calculated based on the mean age-specific mortality rate of local female population. Total 5,681 workers who worked with manual spinning of asbestos for at least one year between 1960 and 1980 were investigated and 795 among them had chest x-ray checked. Results: Among 5,681 female workers, a total number of 858 death cases by all causes were found. The analysis of the percentage of specific causes of death showed that cancer (24.83%) was the first cause of death, and the lung cancer (40.85%) was the most prevalent. SMRs for all cancers (1.35) and for lung cancer (3.88) were significantly elevated than those of the control group. Conclusion: The results indicated that the excess of lung cancer among female workers with manual spinning of asbestos did not likely to be dependent on the amphibole hypothesis, but was likely related to manual spinning of asbestos airborne fibers. |