Chemical Research in Chinese Universities ›› 2023, Vol. 39 ›› Issue (3): 481-491.doi: 10.1007/s40242-023-3049-6

• Article • Previous Articles     Next Articles

Genotoxicity Induced by Low Dose and Mixed Exposure to Haloacetaldehydes, an Emerging Class of Drinking Water Disinfection By-products

YANG Lili, MA Wuren, JIANG Zhiqiang, CHEN Yu, QIU Meiyue, ZHOU Ying, James C. CRABBE, ZHENG Weiwei, QU Weidong   

  1. 1. Key Laboratory of the Public Health Safety, Ministry of Education, Department of Environmental Health, School of Public Health, Fudan University, Shanghai 200032, P. R. China;
    2. Wolfson College, Oxford University, Oxford OX2;
    6 UD, United Kingdom;
    3. Institute of Biomedical and Environmental Science&Technology, University of Bedfordshire, Luton LU1;
    3 JU, United Kingdom
  • Received:2023-02-28 Published:2023-05-25
  • Contact: QU Weidong, ZHENG Weiwei E-mail:wdqu@fudan.edu.cn;weiweizheng@fudan.edu.cn
  • Supported by:
    This work was supported by the Key Project of the National Natural Science Foundation of China(Nos.81630088, 81273035, 81325017) and the Changjiang Scholars Program, Ministry of Education, China(No.T2014089).

Abstract: Haloacetaldehydes(HALs) are the third largest disinfection by-products(DBPs) class by mass in drinking water. Most of them alone in high doses are more cytotoxic and genotoxic than regulated DBPs. However, the toxic effects of mixed exposure to HALs at environmentally relevant levels are still unknown. Given that genotoxicity is critical for risk assessment, we employed multiple genotoxic tests including the Salmonella typhimurium revertant mutation assay(Ames assay), the single cell gel electrophoresis(SCGE) assay, the cytoplasmic blocking micronucleus(CBMN) assay, and the γ-H2AX assay to investigate the genotoxicity of HALs based on the HALs concentrations and components detected in the finished drinking water of Shanghai, China. The results demonstrated the concentrations of HALs were low, ranging from 0.04 μg/L to 4.47 μg/L, and the total concentration was 10.85 μg/L. Although the mutagenicity of HALs was negative even at 1000-fold concentrations in the real world, mixed exposure to 100 and 1000-fold concentrations HALs resulted in DNA and chromosomal damage in human hepotocyte(HepG2) cells. HALs significantly increased the levels of reactive oxygen species(ROS) and γ-H2AX and activated nuclear factor erythroid-derived factor 2- related factor 2(NRF2) pathway-related protein expressions in HepG2 cells. The antioxidant NAC could ameliorate NRF2 pathwayrelated protein expression and DNA damage caused by HALs, suggesting that the genotoxicity of mixed exposure to HALs involved cellular oxidative stress and NRF2 pathway activation.

Key words: Unregulated disinfection by-product, Haloacetaldehyde, Mixed exposure, Genotoxicity