Objective To determine whether there was excessive risk of cancer among workers exposed to chrysotile fiber alone by applying a meta-analysis technique. Methods All data meeting the criteria of cohort studies on c...Objective To determine whether there was excessive risk of cancer among workers exposed to chrysotile fiber alone by applying a meta-analysis technique. Methods All data meeting the criteria of cohort studies on cancer mortality among workers exposed only to chrysotile were incorporated into meta-analysis. Pooled standardized mortality ratios (SMRs) and their corresponding 95% confidence intervals (CIs) for main cancer sites were calculated using two approaches of unweighted ratio and random effect model. The heterogeneity and its sources of the results were examined with a Q-statistic and Z-score test. The dose-response effect as reflected in the percentage of all deaths due to mesothelioma served as a proxy measure of chrysotile exposure. Results A cohort of twenty six workers exposed to chrysotile alone was summarized. The significantly elevated meta-SMRs for all deaths (1.27), all cancers (1.28), cancers of respiratory organs (2.51), cancers of lung (2.35) and cancers of stomach (1.24) were observed. The significantly elevated meta-SMRs for lung cancer within occupational strata were observed among textile workers (3.55), asbestos product manufacturers (3.30), miners and millers (2.24), cement product workers (1.22), and for stomach cancer among asbestos product manufacturers (1.49). Meta-SMRs for cancers at other sites were not significant. Meta-SMR for lung cancer showed an increasing trend with an elevated percentage of all deaths from mesothelioma, but no such trend for stomach cancer. Conclusion There are excessive risks of lung cancer and mesothelioma among workers exposed to chrysotile fiber alone, and likely no convincing indication of an etiological association between chrysotile exposure and cancers at other sites.展开更多
To investigate the mortality of malignant tumor in female workers exposed to chrysotile asbestos.Methods A retrospective cohort study of female workers was conducted,who had been engaged in the manual spinning of chry...To investigate the mortality of malignant tumor in female workers exposed to chrysotile asbestos.Methods A retrospective cohort study of female workers was conducted,who had been engaged in the manual spinning of chrysotile in family with more than one year between January 1,1960 and December 31,1980.Resuits A total of 144 persons were found to be dead from cancer.Among them the most frequent was lung cancer(74), and the second liver cancer(27),and the third stomach cancer(18).Standardized mortality ratio(SMR)from total malingnant tumor and lung cancer were 1.16(P<0.05)and 4.17(P<0.01),respectively based on the control population of the same region.Conclusion A significant excess death from lung cancer was found among female workers who had been exposed to chrysotile.展开更多
基金This study was partially supported by a grant from the Research Foundation in the year of 1997 of the Japan-China Medical Association (No. 001).
文摘Objective To determine whether there was excessive risk of cancer among workers exposed to chrysotile fiber alone by applying a meta-analysis technique. Methods All data meeting the criteria of cohort studies on cancer mortality among workers exposed only to chrysotile were incorporated into meta-analysis. Pooled standardized mortality ratios (SMRs) and their corresponding 95% confidence intervals (CIs) for main cancer sites were calculated using two approaches of unweighted ratio and random effect model. The heterogeneity and its sources of the results were examined with a Q-statistic and Z-score test. The dose-response effect as reflected in the percentage of all deaths due to mesothelioma served as a proxy measure of chrysotile exposure. Results A cohort of twenty six workers exposed to chrysotile alone was summarized. The significantly elevated meta-SMRs for all deaths (1.27), all cancers (1.28), cancers of respiratory organs (2.51), cancers of lung (2.35) and cancers of stomach (1.24) were observed. The significantly elevated meta-SMRs for lung cancer within occupational strata were observed among textile workers (3.55), asbestos product manufacturers (3.30), miners and millers (2.24), cement product workers (1.22), and for stomach cancer among asbestos product manufacturers (1.49). Meta-SMRs for cancers at other sites were not significant. Meta-SMR for lung cancer showed an increasing trend with an elevated percentage of all deaths from mesothelioma, but no such trend for stomach cancer. Conclusion There are excessive risks of lung cancer and mesothelioma among workers exposed to chrysotile fiber alone, and likely no convincing indication of an etiological association between chrysotile exposure and cancers at other sites.
文摘To investigate the mortality of malignant tumor in female workers exposed to chrysotile asbestos.Methods A retrospective cohort study of female workers was conducted,who had been engaged in the manual spinning of chrysotile in family with more than one year between January 1,1960 and December 31,1980.Resuits A total of 144 persons were found to be dead from cancer.Among them the most frequent was lung cancer(74), and the second liver cancer(27),and the third stomach cancer(18).Standardized mortality ratio(SMR)from total malingnant tumor and lung cancer were 1.16(P<0.05)and 4.17(P<0.01),respectively based on the control population of the same region.Conclusion A significant excess death from lung cancer was found among female workers who had been exposed to chrysotile.
