三峡库区腹地水体微生物污染调查及其风险评价

第十一届“挑战杯”全国大学生课外学术科技作品竞赛重庆参赛作品作品名称：三峡库区腹地水体微生物污染调查及其风险评价申报者姓名（集体名称）：“三峡库区水体微生物污染监测”课题组类别：■自然科学类学术论文□哲学社会科学类社会调查报告和学术论文□科技发明制作A类□科技发明制作B类报送方式：□省级报送作品□高校直送作品第十一届“挑战杯”全国大学生课外学术科技竞赛作品三峡库区腹地水体微生物污染调查及其风险评价MicrobialContaminationInvestigationandRiskAssessmentofWatersintheThreeGorgesReservoirArea作者：“三峡库区水体微生物污染监测”课题组指导教师：肖国生地址：重庆市万州区沙龙路二段780号邮编：404000第十一届“挑战杯”全国大学生课外学术科技竞赛作品中文摘要对库区水体微生物污染调查和风险评估有助于了解其水质卫生状况。08年3月、7~8月和11月从万州、云阳、开县和忠县的21个监测点共采集40份水样，用平板菌落计数法和多管发酵法分别测定水样的细菌总数和总大肠菌群数，结合水体接触问卷调查，用β-泊松模型对水样大肠杆菌感染概率进行初步评价。结果发现，89.5%（34/38）为极不清洁水，10.5%为不清洁和不太清洁水。根据国家地表水环境质量标准判断，28.9%（11/38）为V类、7.9%（3/38）为IV类、26.3%（10/38）为III类、26.3%（10/38）为II类、10.5%（4/38）为I类。主要表现为排污口附近的江河水和经城的河水污染较重，污水处理厂下游、城郊支流和远离排污口的江水污染较轻，而不同季节对细菌总数的影响大，对总大肠菌群数没影响。调查发现，两岸居民接触江水的主要方式为游泳，占调查人数的19.64％，接触江水后平均每人误摄入水量为28.4mL，其健康主诉主要症状表现为皮肤红疹发痒（21.4%）、消化道症状（9%）、眼感染（7.1%）、耳感染（5.4%）。大肠杆菌感染风险初步评价发现，监测水体属I~III类地表水的大肠杆菌感染概率在1.8×10-9~2.8×10-7间；属IV和V类的感染概率在4.8~7.2×10-7及以上。研究表明，长江两岸的排污口和经城的长江支流对三峡水库的微生物污染较大，应采取相应措施。关键词：三峡库区；细菌总数；总大肠菌群；风险评价第十一届“挑战杯”全国大学生课外学术科技竞赛作品英文摘要Abstract:MicrobiologicalmonitoringandriskassessmentoftheThreeGorgesWaterReservoirconducestotheunderstandingofthepublichealthstateofitswaterquality.40watersampleswerecollectedfrom21monitoringsiteslocatedatWanzhou,Yunyang,Kaixian,ZhongxianinMarch,JulytoAugust,Novemberin2008,respectively.Thetotalbacteria(mL-1)andtheColiform(L-1)inwatersamplesweredetectedusingflat-panelandmulti-barrelfermentationmethods,respectively.Combiningquestionnairesofexposuretothewaters,thebeta-PoissonmodelwasusedtoassesstheprobabilityofE.coliinfectioninmonitoringwaters.Theresultsshowedthat89.5%(34/38)watersamplesweretheverydirtywater,10.5%werethedirtywaterandnotsocleanwater.Accordingtothenationalsurfacewaterenvironmentalqualitystandards,28.9%(11/38),7.9%(3/38),26.3%(10/38),26.3%(10/38),and10.5%(4/38)ofwatersamplesbelongedtoV,IV,III,IIandI-classwaterquality,respectively.Thesurfacewatersinthevicinityofsewageeffluentsandriversacrossthecitywereseverelypolluted,andthesurfacewatersawayfromsewageeffluentsandinthedownstreamofsewagetreatmentplantsandtheriversacrosssuburbwereslightlypolluted.Thetotalbacteriaweresignificantlyaffectedandthetotalcoliformwasnotaffectedbyseasons.Thesurveyofexposuretowatersshowedthat19.64%ofinquiredpeopleexposedthewatersbyswimming.28.4mLwaterwasswallowedperperson.Theexposedpersonshad21.4%skinhealthcomplaints;9%gutcomplaints;7.1%eyecomplaints;and5.4%earcomplaints.AccordingtoE.coliriskassessment,theprobabilityofE.coliinfectionofmonitoringwatersbelongedtoItoIIIandIVtoVclasswaterwas1.8×10-9~2.8×10-7,4.8~7.2×10-7,respectively.TheresearchesmanifestedthattheThreeGorgesWaterReservoirispollutedbytheseweragesandurbanbranchesandtheprotectedmeasuresshouldbeadopted.Keywords:ThreeGorgesReservoirArea;TotalBacteria;Coliform;RiskAssessment第十一届“挑战杯”全国大学生课外学术科技竞赛作品目录前言·······················································································································································11材料与方法··································································································································11.1培养基·········································································································································11.2采样时间···································································································································11.3采样方法·································································································································21.4采样点·········································································································································21.5细菌总数和总大肠菌群数的测定··············································································21.6水体污染程度的分析·········································································································21.7大肠杆菌感染风险初步评价················································································32结果···········································································································································42.1不同季节监测点水样细菌总数检测结果·····························································4第十一届“挑战杯”全国大学生课外学术科技竞赛作品2.2不同季节监测点水体总大肠菌群数检测结果···················································42.3三峡水库两岸居民水体接触的问卷调查结果·············································52.4监测点水体微生物污染情况分析及大肠杆菌感染风险评价结果·········72.5季节和水温对监测点水体微生物污染变化的影响·········································83讨论···············································································································································83.1在三峡库区开展水体微生物污染调查的意义··················································83.2污水、废水和长江支流对水库水质的影响···························································83.3季节和水温对细菌的影响及原因分析··································································93.4大肠杆菌感染风险评价的意义、存在的问题······················································10参考文献·················································································