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Indexed by:期刊论文

Date of Publication:2020-10-01

Journal:ENVIRONMENTAL HEALTH PERSPECTIVES

Volume:128

Issue:10

ISSN No.:0091-6765

Abstract:BACKGROUND: Groundwater is a main drinking-water source, for Chinese rural residents. The overall pollution status of organic micropollutants (OMPs) and metals in the groundwater and corresponding health risks are unknown.
   OBJECTIVES: Our objective, was to comprehensively screen for and assess the, health risks of OMPs and metals in groundwater of rural areas in China where groundwater is used for drinking so as to provide a benchmark for monitoring and improving groundwater quality in future developments.
   METHODS: One hundred sixty-six groundwater samples were collected in the rural areas of China, and 1,300 OAPs and 25 metals were screened by GC-MS, LC-QTOF/MS, and lICP-MS analysis. To assess the noncarcinogenic and carcinogenic risks of the detected pollutants, missing toxicity threshold values were extrapolated from existing databases or predicted by quantitative structure-activity relationship (QSAR) models. Monte Carlo simulation was performed to account for uncertainties in the exposure parameters and toxicity thresholds.
   RESULTS: Two hundred thirty-three OMPs and 25 metals were detected from the 166 samples. The concentration summation for the, detected OMPs ranged from 2.9 to 1.7 x 10(5)ng/L among the different sampling sites. Cumulative, noncarcinogenic risks for the, OMPs were estimated to be negligible. However, high metal risks were calculated in 23% of the sites. Forty-two carcinogens (including 38 OMPs) were 'identified and the cumulative carcinogenic risks in 34% of the sites were calculated to he >10(-4) (i.e., one excess cancer case in a population of 10 thousand people). The carcinogenic risks were estimated to he mainly associated with exposures to the 'metals, which were calculated to contribute 79% (0-100%) of the cumulative carcinogenic risks.
   Discussion: The overall status of OMPs and metals pollution in the, groundwater and the corresponding health risks were determine-d preliminarily, which may provide a benchmark for future, efforts in China to ensure, the safety of thinking water for the local residents in rural are-as. The, joint application of QSARs and Monte Carlo simulation provided a feasible way to comprehensively assess the health risks of the large and ever-increasing number of pollutants detected in the aquatic environment.