title: Using physiologically based pharmacokinetic models to estimate the health risk of mixtures of trihalomethanes from reclaimed water.
abstract: To estimate the health risk of mixture of trihalomethanes (THMs) from reclaimed water during toilet flushing, the interaction-based Hazard Index (HI(interaction-based)) and the mixture carcinogenic risk (CRM) according to tissue dose were conducted through the integrated use of both the exposure concentrations model and the physiologically based pharmacokinetic (PBPK) model of THMs. Monte Carlo simulations were employed to implement the probabilistic risk analysis and sensitivity analysis. Nine samples were analyzed, which were collected from J Water Reclamation Plant (JWRP) in Tianjin of China. The results indicated that the mean HI(interaction-based) (=0.85) was lower than the acceptable risk level (=1). The probability that the HI(interaction-based) exceeded the acceptable risk level is 22.97%. For carcinogenic risk, the CRM ranges from 9.41×10(-7) to 3.54×10(-5), with a mean of 5.49×10(-6). Moreover, the probability of exceeding the acceptable risk level (1×10(-6)) is near 100%. And the values of HI(interaction-based) from sample no. 1, 5, and 7 exceeded 1, while the values of CRM for all samples exceeded 1×10(-6). Consequently, the reclaimed water used for flushing toilets should be paid more attention, though non-carcinogenic effect is relatively small. Furthermore, the concentrations of DBCM had greater impact on both the carcinogenic and non-carcinogenic risk based on sensitivity analysis.
authors.affiliation: School of Marine Science and Technology, Tianjin University, Tianjin 300072, China; School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China. Electronic address: nzg@tju.edu.cn.
authors.forename: Zhiguang
authors.initials: Z
authors.lastname: Niu
authors.affiliation: School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China. Electronic address: haijiaoxue@126.com.
authors.forename: Xue
authors.initials: X
authors.lastname: Zang
authors.affiliation: College of Environmental Science and Engineering, Nankai University, Tianjin 300071, China. Electronic address: zhangying@nankai.edu.cn.
authors.forename: Ying
authors.initials: Y
authors.lastname: Zhang
mesh_terms: D000393:Air Pollutants / Q000493:pharmacokinetics / Q000633:toxicity; D003198:Computer Simulation; D006801:Humans; D019570:Inhalation Exposure / Q000009:adverse effects* / Q000032:analysis; D008954:Models, Biological; D009010:Monte Carlo Method; D009369:Neoplasms; D059027:Recycling; D018570:Risk Assessment; D014038:Toilet Facilities; D022882:Trihalomethanes / Q000493:pharmacokinetics / Q000633:toxicity; D014874:Water Pollutants, Chemical / Q000493:pharmacokinetics / Q000633:toxicity
chemical_list: D000393:Air Pollutants; D022882:Trihalomethanes; D014874:Water Pollutants, Chemical
keywords: Human risk assessment; Mixture exposure; PBPK model; Reclaimed water; Trihalomethanes