2012-2018年北京市昌平区农村生活饮用水微生物监测

Analysis of microbial indicators of rural drinking water in Changping district of Beijing,2012-2018

目的了解北京市昌平区农村饮用水微生物污染状况,探讨影响昌平区农村饮用水微生物指标合格率的因素,为改善农村生活饮用水卫生状况提供科学依据。方法收集昌平区2012-2018年15个涉农镇内农村自备井枯水期和丰水期出厂水和末梢水的总大肠菌群数、大肠埃希菌数和菌落总数的监测结果,以及自备井的基本情况,采用χ^(2)检验比较组间合格率的差异,运用Logistic回归模型进行影响因素分析。结果共检测1082件农村生活饮用水,微生物总体合格率为72.18%,菌落总数、总大肠菌群和大肠埃希菌的合格率分别为98.52%、72.55%和95.01%。微生物综合指标、菌落总数和总大肠菌群的合格率呈逐年上升趋势(χ^(2)=14.548,P<0.001;χ^(2)=8.095,P=0.04;χ^(2)=15.954,P<0.001)。枯水期微生物综合合格率、总大肠菌群和大肠埃希菌的合格率分别为80.40%、80.77%和97.59%,均大于丰水期(χ^(2)=33.530,P<0.001;χ^(2)=33.816,P<0.001;χ^(2)=15.281,P<0.001);未消毒、按要求消毒及偶尔消毒的自备井以上指标的合格率不全相同(χ^(2)=23.289,P<0.001;χ^(2)=22.510,P<0.001;χ^(2)=10.643,P=0.005);非山区以上指标的合格率分别为59.38%、60.07%和93.40%,均大于山区(χ^(2)=34.562,P<0.001;χ^(2)=34.640,P<0.001;χ^(2)=7.438,P=0.006);浅井、深井和泉水微生物综合指标、总大肠菌群的合格率均不全相同(χ^(2)=38.742,P<0.001;χ^(2)=38.829,P<0.001),大肠埃希菌的合格率亦不全相同(Fisher确切概率法,P<0.001)。多因素Logistic回归结果显示,是否为山区、水期类型、水源类型、消毒方式为影响水样微生物指标的综合合格率的因素。结论昌平区农村饮用水微生物指标的合格率需进一步提高,水期类型、水源类型、消毒方式均不同程度影响其合格率,建议完善并加强消毒管理,加强饮水安全健康教育。

Objective To explore the status of microbial contamination of rural drinking water and its main influencing factors in Changping district of Beijing,so as to provide scientific references for improving the sanitary condition of drinking water in rural areas.Methods Data of total coliform,Escherichia coli and total colonies of the factory and tap water in the dry and wet periods in 15 agricultural related towns in Changping district during 2012-2018 were collected.Chi-square test was used to compare the difference of the lattice rates of different combinations.The influencing factors were detected by logistic regression model.Results A total of 1082 rural drinking water samples were tested.The overall qualified rate of microbial indicators was 72.18%,among which,the total colonies,total coliforms and Escherichia coli were 98.52%,72.22%and 95.01%,respectively.The qualified rate of microbial indicators,total colonies and total coliform were increased year by year(χ^(2)=14.548,P<0.001;χ^(2)=8.095,P=0.04;χ^(2)=15.954,P<0.001).The qualified rates of microbial indicators,total coliform flora and Escherichia coli in dry season were 80.40%,80.77%and 97.59%respectively,which were higher than those in wet season(χ^(2)=33.530,P<0.001;χ^(2)=33.816,P<0.001;χ^(2)=15.281,P<0.001),and which were 59.38%,60.07%and 93.40%respectively in non-mountainous areas,higher than in mountainous areas(χ^(2)=34.562,P<0.001;χ^(2)=34.640,P<0.001;χ^(2)=7.438,P=0.006),and were not all the same among wells that disinfected with different method(χ^(2)=23.289,P<0.001;χ^(2)=22.510,P<0.001;χ^(2)=10.643,P=0.005).The qualified rates of microbial indicators,total coliform flora in deep well,shallow wells and springs were not all the same(χ^(2)=38.742,P<0.001;χ^(2)=38.829,P<0.001),and the qualified rates of escherichia coli were also not all the same among them(Fisher exact probability,P<0.001).Whether mountain areas,water period types,water source types and disinfection method were the factors influencing the qualified ratio of microbial indicators.Conclusions The qualified rate of microbial indicators of rural drinking water in Changping district needs to be further improved.The water period type,water source type and disinfection method all affect the qualified rate.It is suggested to improve and strengthen disinfection management and strengthen drinking water safety and health education.