再生水处理过程中轮状病毒的变化规律及风险评价（Change of Rotavirus in Sewage Treatment Processes and Associated Health Risk Assessment）

为探讨污水处理厂不同处理工艺段对轮状病毒(Rotavirus)的去除效果及再生水回用中轮状病毒对暴露人群的健康风险水平,于2006年11月至2007年10月连续对北京市某污水厂各工艺段出水的轮状病毒进行了分析,并应用Beta-Possion模型对回用再生水中轮状病毒对暴露人群的健康风险水平进行了评价.结果表明,36个实测水样中,轮状病毒检测结果为阳性的样品13个,占总样品数的36.1%.阳性样品主要分布在2006年11月、12月和2007年1月、2月、4月、8月和10月所采集的样品中,各月份阳性样品所占比例分别依次为100%、100%、100%、33.3%、66.7%、33.3%和100%.二级处理工艺对轮状病毒的去除率为2.68-lg,二级处理出水经过混凝沉淀和砂滤两种深度处理后得到再生水,深度处理工艺平均去除率为3.01-lg.二沉出水回用对不同职业暴露人群的年均感染概率风险值范围为0.35×10-2~10.36×10-2,再生水回用不同职业暴露人群年平均感染风险概率值范围为0.23×10-2~6.82×10-2,二沉出水、再生水回用导致的道路喷洒职业工人轮状病毒暴露感染风险值最大,分别达到了39.65×10-2和36.82×10-2,存在着一定的健康风险.

Change of Rotavirus in Sewage Treatment Processes and Associated Health Risk Assessment

To understand the elimination abilities of different treatment processes in one wastewater treatment plant and the health risk level to exposure people of wastewater reuse from the wastewater treatment plant,the total of 36 water samples was collected from different treatment processes in one sewage treatment plant of Beijing from November 2006 to October 2007 and a real time fluorescent quantitative PCR method with SYBR Green I was used to quantify the rotaviruses of these water samples.According to the results,It was showed that the ratio of rotavirus positive samples was 36.1% relative to the total samples,and the distributions of rotaviruses in influents and effluents of three STRs were quite similar,abundant in cold weather (from October to March) and less prevail in warm weather (from April to September).The results indicated that the removal rate of secondary treatment process for rotavirus was 2.68-1g,while secondary effluent after coagulation and filtration were 3.01-1g.According to the health risk assessment results,it was suggested that the average health risk level range of different occupation exposure people from the secondary treatment wastewater reuse was 0.35×10~(-2)～ 10.36×10~(-2),and the average health risk level range of different occupation exposure people from the secondary coagulation and filtration wastewater reuse was 0.23×10~(-2)～6.82×10~(-2).the maximum health risk level occurred on the street cleaning workors,the maximum values from secondary treatment process and secondary effluent after coagulation and filtration effluent were 39.65×10~(-2)和36.82×10~(-2) respectively,which suggested that certain health risk level produced by the rotavirus occurred on the street cleaning workers.