An Investigation And Study On Traceability And Fecal Contaminated Microbes Of Source Waterand Drinking Water In A Certain North-eastern Place

Water is indispensable to human survival, but nowadays there are some people not getting health and safety of drinking water, and some people also die from water-borne diseases because of drinking water by microbical contamination. Sometimes because domestic sewage and feces with rainwater run off into the water, it causes an important source of water by biological pollution. At present our country mainly detects the total bacteria count, total coliforms, heat-resistant coliform bacteria and Escherichia coli in the aquatic microbial contamination in monitoring and evaluation, but the number of four microbial indicators can be only used to show that water is the degree of microbial contamination, but can’t show the real source of fecal contamination in water. It is because Microbial Source Tracking (MST) technology is put forward that the problem has been solved. Source water and drinking water polluted by waste microbial related to condition investigation, and selects Escherichia coli as indicator, and meanwhile it is traced to determine the microbial contamination source to provide the basis for control waste pollution and to establish Escherichia coli bacterium gene fingerprint library foundation for the region.ObjectiveTo investigate and study fecal microbes of water source and drinking water on pollution condition in a certain north-easten region, on the basis of research to track source and establish known sources of Escherichia coli rep-PCR gene fingerprint library,then cultivation from unknown sources in the water samples to determine the pollution sources, and remedies for governance of water pollution to adopt effective management and control to provide technical support.MethodsIn the summer and autumn of 2015,the related samplings, including source water and drinking water, were collected respectively at some place in northeast China, human excrement and animal waste, meanwhile were also upstream collected along the rive from waterworks. Sample testing included total bacteria count, total coliforms and Escherichia coli three sanitary microbiology indicators and Escherichia coli O157:H7, Salmonella, Shigella, Vibrio Parahaemolyticus and Staphylococcus aureus five pathogenic microbiology indicators. The five kinds of pathogenic microbiology indicators in the water were tested in diarrhea or stools, and all excrement and water samples were separated to cultivate Escherichia coli at the same time.DNA extracted from the Escherichia coli genome, and select BOX AIR as rep-PCR primers for amplification,agarose gel electrophoresis.Bionumerics 7.1 software is used to analyse the rep-PCR results of cluster analysis, first of all, establish a known source of Escherichia coli characteristic fingerprint database, then they will be grouped according to different sources, respectively according to seven sources (people, pig, cattle, sheep, chicken, duck, goose),three sources(human, domestic, poultry) and two sources (people and animal) for discriminant analysis, in the end, the software for the unknown source water separation Escherichia Coli rep-PCR fingerprint will compare with the known source fingerprint, pollution sources will be determined.Results(1) Survey results of source water and drinking water polluted by waste microbesDisqualification rates of sterilization treated water, rural self-drilled well and source water due to microbiology indicators are 20.00%,95.45% and 54.00% respectively. Exceeding standard of total coliforms and Escherichia coli is the main factor causing high water fraction defective,it is possible to prove the existence of feces pollution in source water and drinking water in the region.(2) The Escherichia coli detection resultsIn the end, a total of 1044 strains of Escherichia coli identified, including 116 strains of water source and 928 strains of waste source.(3) Pathogenic bacteria detection resultsChecked out 8 strains of pathogenic bacteria, and respectively detected two strains intestinal Salm.ent. diarizonae,1 strain of Salmonella. israel in water samples. In the human diarrhea feces, checked out 1 strain Vibrio parahaimolyticus; source of chicken diarrhea feces has detected Salmonella dublin 1 strain; in the source of duck and pig feces, respectively checked out 3 strains Salmonella enterica ssp diarizonae (including duck source 1 strain, pig source 2 strains).Among all samples, Escherichia coli O157:H7, Vibrio parahaimolyticus andStaphylococcusaureus were not checked out.(4)Known source of Escherichia coli characteristic fingerprint establishmentFrom the 928 strains of known sources of Escherichia coli’s rep-PCR fingerprint,816 strains are screened fingerprint and established a known source of people and animals origin indicator bacteria DNA fingerprint.(5)The unknown source and the known source fingerprint matching results104 strains isolated from water samples of Escherichia coli, according to the classification of three sources of judgment results,30 strains(28.8%) from poultry,17 strains(16.3%) from domestic,18 strains(17.3%) from human,39 strains(37.5%) of the source is unknown. According to two sources of judgment results,18(17.8%) strains from people,72 strains(69.2%) from animals and 14 strains(13.5%) of the source is unknown.Conclusion(1) There exist source water and drinking water polluted by feces in this region, water microbiology indicators monitoring should be strengthened to prevent the happening of the medium water-borne diseases.(2) According to research results this time,it is believed that rep-PCR technology can distinguish differences of Escherichia coli from animals and people,and the results mainly come from the animal feces pollution in the region,so management should be strengthened further.