广西地区水域隐孢子虫和贾第鞭毛虫的污染调查

Investigation on Cryptosporidium and Giardia in Guangxi waters

目的了解广西部分城市、乡镇的水源水、出厂水及污水中隐孢子虫和贾第鞭毛虫污染情况,为医疗卫生、水利部门制定科学合理的防控措施提供理论依据。方法于2015年12月-2023年3月以广西地区珠江流域、红河流域、桂南沿海诸河的9条江以及中部3个县的18个镇为采样点,使用《生活饮用水标准检验方法》(GB/T 5750.12-2023)中的多孔海绵滤膜模块采样及快速淘洗步骤对原水和出厂水进行采集并做隐孢子虫和贾第鞭毛虫检测,同时对水厂进行基本情况调查,检测39份出厂水中的水质相关指标,包括色度、浊度、pH、菌落总数、总大肠菌群、耐热大肠菌群、氯化物、硫酸盐、溶解性总固体、总硬度、耗氧量和氨氮。结果采集水样193份,隐孢子虫检出率为17.6%,贾第鞭毛虫检出率为14.5%;39份出厂水的其他水质检测指标超标率情况,色度为5.1%,浊度为2.6%,pH为5.1%,菌落总数为10.3%,总大肠菌群与耐热大肠菌群均为15.4%,耗氧量为5.1%,氨氮为10.3%,氯化物、硫酸盐、溶解性总固体、总硬度未超标。隐孢子虫与原水氯化物(r=-0.35,P<0.05)、原水硫酸盐(r=-0.34,P<0.05)、原水溶解性总固体(r=-0.45,P<0.05)、原水总硬度(r=-0.38,P<0.05)成负相关,与出厂水菌落总数(r=0.38,P<0.05)、原水浊度(r=0.34,P<0.05)成正相关;贾第鞭毛虫与原水溶解性总固体(r=-0.32,P<0.05)、原水总硬度(r=-0.39,P<0.05)、出厂水总硬度(r=-0.35,P<0.05)、出厂水pH(r=-0.35,P<0.05)成负相关,与出厂水菌落总数(r=0.34,P<0.05)成正相关。结论调查地区的部分原水和出厂水受到隐孢子虫和贾第鞭毛虫的污染,山泉水、水库水、江河水和地下水均有受到污染的风险,完善的水厂处理工艺可以有效地去除水中隐孢子虫和贾第鞭毛虫。

Objective To understand the contamination status of Cryptosporidium and Giardia in source water,factory water and sewage in some cities and towns in Guangxi,and provide a theoretical basis for the medical and health and water conservancy departments to formulate scientific and reasonable prevention and control measures.Methods From December 2015 to March 2023,9 rivers in the Pearl River Basin,Red River Basin,and coastal rivers in southern Guangxi,as well as 18 towns in three counties in the central part of Guangxi were used as sampling points.Use the Filta⁃Max xpress steps in the Methods for the inspection of standards of potable drinking water(GB/T 5750.12-2023)to collect source water and factory water and perform Cryptosporidium and Giardia detection.At the same time,a basic investigation was conducted on the water plant to test the water quality related indicators of 39 factory water samples,including chromaticity,turbidity,pH value,total colony count,total coliform group,thermotolerant coliform group,chloride,sulfate,total dissolved solids,total hardness,oxygen consumption and ammonia nitrogen.Results A total of 193 water samples were collected,the detection rate of Cryptosporidium was 17.6%,and the detection rate of Giardia was 14.5%.Other water quality test indicators of 39 samples of factory water exceeded the standard,including chromaticity of 5.1%,turbidity of 2.6%,pH value of 5.1%,total colony count of 10.3%,total coliform bacteria and thermotolerant coliform bacteria of 15.4%,oxygen consumption of 5.1%,ammonia nitrogen of 10.3%,chloride,sulfate,total dissolved solids,and total hardness were not exceeding the standard.Cryptosporidium was negatively correlated with raw water chloride(r=-0.35,P<0.05),raw water sulfate(r=-0.34,P<0.05),raw water total dissolved solids(r=-0.45,P<0.05),and raw water total hardness(r=-0.38,P<0.05),and was positively correlated with the total colony count in factory water(r=0.38,P<0.05)and raw water turbidity(r=0.34,P<0.05).Giardia was negatively correlated with total dissolved solids in raw water(r=-0.32,P<0.05),total hardness of raw water(r=-0.39,P<0.05),total hardness of factory water(r=-0.35,P<0.05),and pH of factory water(r=-0.35,P<0.05),and was positively correlated with the total colony count in factory water(r=0.34,P<0.05).Conclusions Some raw water and factory water in the survey area were contaminated by Cryptosporidium and Giardia;Mountain spring water,reservoir water,river water and groundwater were all at risk of being contaminated.A complete water plant treatment process could effectively remove Cryptosporidium and Giardia.