摘要
目的研究城镇污水处理厂进出水中特征性致病菌E．coliO157：H7和沙门菌的浓度水平以及次氯酸钠对其及病原指示菌的灭活特性。方法于2012年2—12月，采集北方A污水处理厂的进水及二沉池出水水样，分离、纯培养总大肠菌群（TC）、粪大肠菌群（Fc）、E．coliO157：H7和沙门菌；分别加入有效氯浓度为0（溶剂对照）、0．5、1．0、1．5、2．0mg／L的次氯酸钠溶液接触5、15、30、45、60min。测定TC、FC、E．coliO157：H7和沙门菌的浓度。结果污水处理厂进水中E．coliO157：H7为10^5-10^7cfu／L，沙门菌为10^6-10^8cfu／L；出水中微生物数量均有所下降，但E．coliO157：H7仍高于10^2cfu／L，沙门菌高于10^4cfu／L。纯培养的E．coliO157：H7和指示菌可被0．5mg／L有效氯作用60min灭活，而同条件下沙门菌只能部分被灭活。结论沙门菌在本次调查的污水中浓度水平较高，且比病原指示菌大肠杆菌难以灭活。若单以病原指示菌监测出水水质，存在指示菌达标而其他病原微生物造成环境二次污染的可能。
Objective To investigate the concentration and inactivation of E.coli O157：H7,SalmoneUa spp. and indicator bacteria in the influent and effluent from urban wastewater treatment plant. Methods From February to December in 2012, the total coliform （TC）, fecal coliform （FC）, E. coli O157：H7 and Salmonella were isolated and purified from water samples collected in a sewage treatment plant in northern China, then the purified TC, FC, E.coli O157：O7 and Salmonella were added respectively into sodium hypoehlorite solution with chlorine concentrations of 0 （solvent control）, 0.5,1.0,1.5 and 2.0 mg/L. After 5,15,30,45 and 60 rain of contaction respectively, TC, FC, E.coli O157：O7 and Salmonella were counted, respectively. Results The E.coli O157：H7 and Salmonella spp. in the influent were 105-107 cfu/L and 106-108 efu/L orders of magnitude, respectively. Most of microorganisms were removed after the treatment. However,the E.coli O157：H7 in the effluent was still higher than 102 cfu/L,and that of Salmonella spp. was higher than 10a efu/L. All of the cultured E.coli O157：H7 and indicator bacteria could be inactivated under 0.5 mg/L sodium hypochlorite （as C12） in 60 min,while just some of Salmonella spp. could be inactivated under the same conditions. Conclusion A higher concentration of Salmonella spp. is found in the sewage samples, and it is much harder to inactivate Salmonella spp. compared with pathogens indicator bacteria. Contamination may be occurred by pathogenic microorganisms from effluent,which has been qualified evaluated by the hygienic indicator bacteria, considering that pathogens such as Salmonella spp. were harder to be inactivated than indicator bacteria.
出处
《环境与健康杂志》
CAS
CSCD
北大核心
2013年第12期1084-1086,共3页
Journal of Environment and Health
基金
中国博士后科学基金(20090450057)
国家自然科学基金(51308374
51278174)
关键词
污水
指示菌
沙门菌
大肠杆菌O157
H7
次氯酸钠
灭活特性
Wastewater
Indicator bacteria
SalmoneUa spp.
E.coli O157： H7
Sodium hypoehlorite
Inactivation characteristics
