Study On The Effects Of Bacterial Contamination Of Household Water Purification Equipment And Water Contact Material On Microbial Growth

Although in recent years the improvement of living standards of urban and rural people and the continuous progress of science and technology,drinking water facilities are gradually upgrading,health conditions have improved compared to the previous,but drinking water pollution accidents are still frequently reported.Surveys showed that water purifier sales growth in 2013 reached 20%,domestic penetration rate r.However,the hygiene safety of the water purifier has gradually become the attention focus.According to the literature report,in one water purifier survey,28.6%of the total number of filtered aquatic heterotrophic bacteria was low than tap water in the same residence,while 53.6%of the total number of colonies in water after purification by water purifier exceeded the standard of drinking water in China(100CUF/mL).At the same time,purifier raw materials quality of water purification equipment will also have a great impact on the quality of domestic water.Microbiological examination of domestic drinking water treatment equipment according to the Ministry of Health concerns about drinking water hygiene safety products inspection,including two processes Safety experiments and functional experiments,as well as the total number of colonies,coliform bacteria,heat-resistant coliform bacteria,three test projects.These traditional methods can only show that the removal rate of water purification equipment and water purification equipment contaminated by feces,but it cannot react to the species contaminated by bacteria.As early as in the 1990 of the 20th century,foreign literature on the water purifier Two pollution reported,found that 36%of water purifier effluent concentration of microorganisms below the same residence tap water of microbial concentrations.In our country,the household water purifier can effectively remove the microorganism in the water source,but after the installation and use of the family for some time,the bacterial indicators of water filtration equipment are worthy of study.Purpose:Determine the contamination status of the water purifier and determine the type of bacteria exceeding the standard in the water filter test experiment,and To understand the source of bacterial contamination of some of the water purification materials for microbial growth experiments to determine the impact of water purification materials on microbial growth.For the effective control of pollution and the rational development of standards to protect the health of the people to provide the basis.Content of research:1.Microbial contamination of water purification equipment and analysis of bacteria:According to the standard of the 305 samples of water purification equipment for microbiological testing to understand the product of the pass rate,and the total number of colonies exceeded the sample identification analysis.2.Investigation on microbial contamination of household water purification equipment:Deep into the Tianjin area 52 household water purification equipment users.Understand the use of each water purification equipment,analysis may cause the total number of bacteria out of the water causes.Collected by the water purification equipment without water filtration equipment and water purification equipment filtered 104 samples of water.Bringing to test the colony total,coliform bacteria and Escherichia coli.And analyse of bacterial species.3.Study on the microbial growth of non-metallic materials by contact with water:collecting water purifier materials:Including 15 parts of activated carbon material,water storage material 10,10 parts of water supply material and 5 parts of water filter material.,according to the British Standard "water contact with non-metallic materials on the impact of the water quality" BS 6920:2.4-2000 to carry out experimental research.Results:1.The results showed that the overall performance test failure rate was 8.9%and the immersion test rate was 2.3%.22 kinds of bacteria were identified in the effluent of water purification equipment,and pathogens such as Pseudomonas aeruginosa and Pseudomonas aeruginosa,Klebsiella clot and hemolytic staphylococci were identified in the effluent.2.52 household users took the on-site investigation of Tianjin Household water purification equipment.Results showed that the total number of colony,total coliform group and Escherichia coli were not detected in the source water.The total number of colony detected in water purification equipment is 32(61.5%),among them,15(28.8%)of water purification equipment,the total number of colonies exceeded GB5749-2006 "Drinking water hygiene standards" prescribed limit 100CFU/mL.Among them,the total coliform flora were checked in one water purification equipment.Accounted for 1.9%of all users.Escherichia coli is not detected in the effluent of the water purification equipment.Among them,the rate of activated carbon water purification equipment effluent exceeded was 21.7%,the rate of ultra-filtration structure water purification equipment effluent exceeded was 50%,the rate of reverse osmosis water purification equipment effluent exceeded was 18.8%.Effluent water detected:Bacillus cereus,Staphylococcus aureus,two pathogenic bacteria.At the same time filtration of water also detected rose cook bacteria;the pathogenic bacteria such as rose-cook bacteria,klebsiella-producing acid bacteria,indole-golden bacillus.The use of the user's water purification equipment,the results show that:activated carbon filter used for too long may be related to the total number of water purification equipment.3.Through experimental study on the collection of water purification equipment materials according to the standard British Standard "water contact with non-metallic materials on the impact of water quality" BS 6920:2.4-2000 found:10 parts of granular activated carbon material to promote the growth of microorganisms,other materials do not promote the role of microbial growthConclusion:The pollution of water purification equipment was serious and a wide variety was detected,including Pseudomonas aeruginosa,Staphylococcus aureus,Bacillus cereus three kinds of pathogenic bacteria and a variety of other conditional pathogens.Household water purification equipment,there is a potential risk factor for disease bacteria pollution,should strengthen the detection.Microbial growth can be promoted by certain granular activated charcoal materials in contact with water.The use of granular activated carbon should be strengthened on the disinfection of drinking water,control of microbial contamination.