Risk assessment of Giardia in rivers of southern China based on continuous monitoring  

作　　者：Wei An Dongqing Zhang Shumin Xiao Jianwei Yu Min Yang 

机构地区：[1]State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beifing 100085, China [2]College of Emergency Management, -Henan Polytechnic University, Jiaozuo 454003, China

出　　处：《Journal of Environmental Sciences》2012年第2期309-313,共5页环境科学学报（英文版）

基　　金：supported by the Foundation of Major Science and Technology Program for Water Pollution Control and Treatment (No. 2009ZX07419-002);the National Natural Science Foundation of China (No. 50778171,50809066, 20807013)

摘　　要：The occurrence and risks of Giardia in China have been unclear to date,which has made it difficult to properly manage source water as well as to create reasonable drinking water standards.The levels of Giardia in river networks of several cities in Zhejiang Province,China were found to be in the range of 0-5 oocysts/10 L in the rainy season in 2008.The mortality due to Giardia infection for people in this region was calculated to be from 0 to 1.95 × 10？8 persons using a conditional probability equation.Based on multiple unboiled water intake routes,the disability-adjusted life years（DALYs） due to Giardia infection for people who consumed conventionally treated water was 0.625（95% CI：0.137-2.05） per 105 persons,with the symptom of hospitalization making the highest contribution to total DALYs（0.56 per 105 persons;95% CI：0.122-1.84）.The DALYs decreased to 0.425（95% CI：0.137-2.05） per 105 persons per year for those consuming water treated with advanced technology.These values were lower than the acceptable risk（1.97 × 10？5 DALYs per year）.This study revealed the risk of Giardia infection to the people in river networks of Zhejiang Province for the first time,and provides a method to evaluate the risk of Giardia infection.The results are useful for the modification of drinking water quality standards based on cost-benefit analysis.The occurrence and risks of Giardia in China have been unclear to date,which has made it difficult to properly manage source water as well as to create reasonable drinking water standards.The levels of Giardia in river networks of several cities in Zhejiang Province,China were found to be in the range of 0-5 oocysts/10 L in the rainy season in 2008.The mortality due to Giardia infection for people in this region was calculated to be from 0 to 1.95 × 10？8 persons using a conditional probability equation.Based on multiple unboiled water intake routes,the disability-adjusted life years（DALYs） due to Giardia infection for people who consumed conventionally treated water was 0.625（95% CI：0.137-2.05） per 105 persons,with the symptom of hospitalization making the highest contribution to total DALYs（0.56 per 105 persons;95% CI：0.122-1.84）.The DALYs decreased to 0.425（95% CI：0.137-2.05） per 105 persons per year for those consuming water treated with advanced technology.These values were lower than the acceptable risk（1.97 × 10？5 DALYs per year）.This study revealed the risk of Giardia infection to the people in river networks of Zhejiang Province for the first time,and provides a method to evaluate the risk of Giardia infection.The results are useful for the modification of drinking water quality standards based on cost-benefit analysis.

关 键 词：GIARDIA risk assessment water consumption disability-adjusted life years 

分 类 号：TU991.21[建筑科学—市政工程] S941.523[农业科学—水产养殖]