| 大量研究表明UV对贾第虫包囊具有很好的灭活效果[31-33]。Qian[22]等的研究表明普遍用于水处理的UV剂量对贾第虫的灭活效率足以达到3log的水平。另外，有关臭氧对包囊的有效消毒也有一些报道[34-35]。Ryu[6] 所做的非饮用再生水中贾第虫风险分析如表3所示，该研究所选用的暴露量计算模型与本研究不同之处是考虑了回收率（26%）和贾第虫活性比例（13%），该模型相比式（3）过低估算风险值。该研究得出采用 UV/氯消毒的年风险值为1.86×10-6－2.54×10-6，明显低于单独氯消毒（3.74×10-4－1.58×10-1）和风险警戒限。因此紫外（UV）与氯的联合作用对包囊的灭活效果明显优于单独的氯消毒。综上所述，针对贾第虫采取有效消毒措施有助于其风险消减。
3 结论：
受到贾第虫污染的A再生水厂，其现有工艺不能有效的去除贾第虫，存在一定的健康风险，为了保障水质安全，再生水厂需要对再生水进行有效的深度处理或采用臭氧、紫外等消毒工艺去除或灭活贾第虫包囊。
由于MBR中微生物得到高倍浓缩，如果运行中出现较严重的膜破损现象，其可能导致的健康风险值得关注。
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