我国典型湖泊病原微生物的分布特征与环境行为

Due to the current wastewater treatment process of municipal wastewater treatment plant can not completely remove the virus from the treated wastewater , the pathogenic virus from human and animal feces is widely existed in faecal polluted water、sediment and aquatic organisms(such as shells ).Human pathogenic virus is thought to be the major pathogens causing a variety of waterborne disease outbreak, and have been employed as indicator and/or candidates for controlling water quality in Europe and USA. Human pathogenic virus behavior and health risk assessment in water environment in China is still in the initial research stage, there is an urgent need to develop new methods for detection of pathogenic viruses in water environment and conduct human health risk assessment. Based on the relevant research at home and abroad，the lake Tai is chosen as the research object. Reliance on quantitative PCR and other technique ,we plan to establish and optimize the methods for detecting adenovirus, enteroviruses which may be found in the surface water, sediments, study the titer and influence factor of pathogenic viruses, investigate the resource of adenovirus, enteroviruses in water environment and seiment. Using Beta-Poisson model, combined with China’s population exposure parameters, quantitatively assess the population health risk to the pathogenic viruses and proposed the threshold of enteric viruses in surface water and sediments for protecting human health and controlling the surface waters quality.

由于目前城镇污水处理厂采用的污水处理工艺并不能完全去除污水中的病毒，来源于人畜粪便的致病病毒广泛存在于被人类粪便污染的水、底泥及污染水域中的水生生物（如贝壳类）。人类致病病毒被认为是导致多种水源性疾病爆发的主要病原生物，已经被纳入欧美等国家水环境质量生物污染物检测指标体系和候选清单中。人类致病病毒在水环境中的行为和健康风险评价在我国尚处于起步研究阶段，因此研究并建立检测水环境中致病病毒的方法和进行人群健康风险评价尤为重要。本研究充分借鉴国内外相关研究基础，拟选择我国典型湖泊太湖为研究对象，运用定量PCR等技术，优化湖泊水体、沉积物中腺病毒、肠道病毒的定量PCR分析方法，研究致病病毒的滴度及影响因素，阐述水、沉积物中腺病毒、肠道病毒来源，揭示其在湖泊中的环境行为。采用Beta-Poisson模型，结合我国人群暴露参数，定量评估致病病毒的人群健康风险，提出水环境质量评价的建议阈值。

由于目前城镇污水处理厂采用的污水处理工艺并不能完全去除污水中的病毒，来源于人畜粪便的致病病毒可存在于被人类粪便污染的水、底泥中。人类致病病毒被认为是导致多种水源性疾病暴发的主要病原生物，病毒已经被纳入欧美等国家水环境质量生物污染物检测指标体系和候选清单中。本项目研究并优化了水体和沉积物中病毒浓缩方法，并利用标准曲线，建立了病毒滴度的定量测定方法。以太湖为研究对象，未检测到病毒，说明太湖水质优良，未受到病毒感染。以巢湖流域入湖河流为研究对象，结果显示有条件致病菌的存在。选择太湖流域内某城市河道、沉积物以及该城市某污水处理厂各工艺段进出水、污泥中的腺病毒、肠道病毒，进行周年月度的采样分析，结果显示诺如病毒（NOV）检出率46.07%，其他类型病毒，如RV病毒、札如病毒、轮状病毒、腺病毒等，检出率均低于NOV。野外现场研究对pH、耗氧量、总磷、总氮、电导率和溶解氧进行了同步监测，研究常见环境理化因素对肠道病毒在水体和沉积物中生存的影响，结果显示，水温越高，诺如病毒检出率越低。在环境水体pH为弱碱性，pH=7.35-8.49情况下，NOV检出率随pH升高而降低。实验室研究结果显示病毒具有最高回收率的实验室条件是4℃、pH 3.5，说明病毒更喜低温和酸性环境。在综述病毒环境风险评价的基础上，发现由于病毒在外环境滴度很低，现阶段还难以进行定量评估，并给出健康阈值，还需后续进一步开展更深入的研究。