重庆市二次供水卫生学调查研究

Investigation of the sanitary conditon of secondary drinking water supply in Chongqing City

目的了解重庆市二次供水卫生现状,为政府部门制定管理决策提供技术依据。方法对重庆市39个区县的所有二次供水单位进行现场卫生状况调查,并在水箱用水点采集水样,对总大肠菌群、菌落总数、色度、浑浊度、臭和味、肉眼可见物、p H等指标进行检测。最后对调查结果进行统计学分析。结果重庆市共有二次供水单位1 649家;二次供水卫生许可证持有率为53%;水箱定期消毒单位比例为25.02%;预防性卫生监督审查率为24.32%;定期清洗的水箱水质合格率高于没有定期清洗的水箱水质,经卡方分析,P<0.05,差异具有统计学意义。共采集975份水样,经检测合格917份,合格率为94.05%。结论重庆市二次供水存在安全隐患。有卫生许可证的供水单位卫生现状优于无证单位;二次消毒和水箱的定期清洗是防止二次供水二次污染的关键因素;消毒剂投加不合理、开展预防性卫生监督审查单位比例低等问题突出。

Objective To investigate the sanitary condition of secondary water supply in Chongqing so as to provide the technical basis for making a management decision for the government.Methods All secondary water supply entities of 39 districts in Chongqing were inspected for sanitary condition and water quality, and indicators of total coliforms, total bacterial count, color, turbidity, odor and taste, visible matter, PH and others were tested.Finally,sanitary condition of secondary water supply were analyzed by statistic analysis.Results 1649 entities of secondary water supply were investigated; entity with qualified sanitation certificate accounted for 53% and entity with regular sterilization accounted for 25.02%; rate of preventive health supervisory review was 24.32%. The water qualified rate of regular cleaning tank were higher than the no regular cleaning tank（p0.05）. Among 975 water samples, 917 samples were qualified, and the qualified rate was 94.05%. Conclusion The sanitary condition of secondary water supply is qualified in Chongqing, but there are still exists safety issues. The sanitary condition of entity with qualified sanitation certificate were better than no license one. Second disinfecting and regular cleaning tank were the key factors which prevent the second pollution for secondary water supply. Problems of unreasonable addition of disinfectants, the low rate of preventive health supervisory review were serious.