title: A toxicity-based method for evaluating safety of reclaimed water for environmental reuses.
abstract: A large quantity of toxic chemical pollutants possibly remains in reclaimed water due to the limited removal efficiency in traditional reclamation processes. It is not enough to guarantee the safety of reclaimed water using conventional water quality criteria. An integrated assessment method based on toxicity test is necessary to vividly depict the safety of reclaimed water for reuse. A toxicity test battery consisting of lethality, genotoxicity and endocrine disrupting effect was designed to screen the multiple biological effects of residual toxic chemicals in reclaimed water. The toxicity results of reclaimed water were converted into the equivalent concentrations of the corresponding positive reference substances (EQC). Simultaneously, the predicted no-effect concentration (PNEC) of each positive reference substance was obtained by analyzing the species sensitivity distribution (SSD) of toxicity data. An index "toxicity score" was proposed and valued as 1, 2, 3, or 4 depending on the ratio of the corresponding EQC to PNEC. For vividly ranking the safety of reclaimed water, an integrated assessment index "toxicity rank" was proposed, which was classified into A, B, C, or D rank with A being the safest. The proposed method was proved to be effective in evaluating reclaimed water samples in case studies.
authors.affiliation: College of Resource Environment and Tourism, Capital Normal University, Beijing 100048, China. Electronic address: xu-jianying@163.com.
authors.forename: Jianying
authors.initials: J
authors.lastname: Xu
authors.affiliation: College of Resource Environment and Tourism, Capital Normal University, Beijing 100048, China; State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
authors.forename: Chuntao
authors.initials: C
authors.lastname: Zhao
authors.affiliation: State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China. Electronic address: weidb@rcees.ac.cn.
authors.forename: Dongbin
authors.initials: D
authors.lastname: Wei
authors.affiliation: State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
authors.forename: Yuguo
authors.initials: Y
authors.lastname: Du
mesh_terms: D003247:Conservation of Natural Resources; D052244:Endocrine Disruptors / Q000633:toxicity; D007928:Lethal Dose 50; D009152:Mutagenicity Tests; D018675:Toxicity Tests; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D052244:Endocrine Disruptors; D014874:Water Pollutants, Chemical
keywords: Reclaimed water; Safety; Toxicity; Water quality