Liu Jun-Ling, Zhang Xiao-Pan, Peng Chen-Wei, Luo Hai-Yuan, Liu Ai-Lin
Key Laboratory of Environment and Health, Ministry of Education & Ministry of Environmental Protection, and State Key Laboratory of Environmental Health (Incubating), School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.
Wuhan Center for Disease Control and Prevention, Wuhan 430022, China.
Environ Toxicol Chem. 2025 May 16. doi: 10.1093/etojnl/vgaf129.
Halogenated disinfection byproducts are contaminants in drinking water that pose a significant public health concern. The intestine is particularly susceptible to the effects of disinfection byproducts through oral ingestion; however, the intestinal toxicity of these compounds remains largely unexplored. This study aimed to assess the impact of ten haloacetic acids, a major class of drinking water disinfection byproducts, on intestinal barrier function using Caenorhabditis elegans as a model animal. Additionally, changes in the expression of five genes related to intestinal barrier function (mucin-like gene (mul-1), zonula occludens ortholog gene (zoo-1), gut esterase 1 gene (ges-1), cytochrome P450 gene (cyp13a7), and saposin-like protein family gene (spp-5)) were examined using quantitative real-time polymerase chain reaction. Among the investigated haloacetic acids (chloroacetic acid, bromoacetic acid, iodoacetic acid, dibromoacetic acid, dichloroacetic acid, bromochloroacetic acid, bromodichloroacetic acid, dibromochloroacetic acid, trichloroacetic acid, and tribromoacetic acid), exposure to five haloacetic acids (dichloroacetic acid, bromodichloroacetic acid, dibromochloroacetic acid, trichloroacetic acid, and tribromoacetic acid) could lead to significant disruption of the intestinal barrier, as evidenced by the induced increase in intestinal permeability in C. elegans. The order of enterotoxicity, based on assessments of intestinal permeability, is trichloroacetic acid > bromodichloroacetic acid ≈ dibromochloroacetic acid ≈ tribromoacetic acid > dichloroacetic acid. These five compounds suppressed the expression of both the tight junction (zoo-1) and xenobiotic-metabolising (ges-1) genes, suggesting that these two genes may be of vital importance in haloacetic acid-induced intestinal toxicity. This work contributes to improving the available knowledge on the toxicity of haloacetic acids and provides a basis for understanding their mechanism of intestinal toxicity.
卤代消毒副产物是饮用水中的污染物，对公众健康构成重大威胁。肠道通过口服摄入特别容易受到消毒副产物的影响；然而，这些化合物的肠道毒性在很大程度上仍未得到探索。本研究旨在以秀丽隐杆线虫为模式动物，评估一类主要的饮用水消毒副产物——十种卤乙酸对肠道屏障功能的影响。此外，还使用定量实时聚合酶链反应检测了与肠道屏障功能相关的五个基因（粘蛋白样基因（mul-1）、紧密连接同源基因（zoo-1）、肠道酯酶1基因（ges-1）、细胞色素P450基因（cyp13a7）和类鞘脂激活蛋白家族基因（spp-5））表达的变化。在所研究的卤乙酸（氯乙酸、溴乙酸、碘乙酸、二溴乙酸、二氯乙酸、溴氯乙酸、溴二氯乙酸、二溴氯乙酸、三氯乙酸和三溴乙酸）中，暴露于五种卤乙酸（二氯乙酸、溴二氯乙酸、二溴氯乙酸、三氯乙酸和三溴乙酸）会导致肠道屏障的显著破坏，秀丽隐杆线虫肠道通透性增加即证明了这一点。根据肠道通透性评估，肠毒性顺序为三氯乙酸>溴二氯乙酸≈二溴氯乙酸≈三溴乙酸>二氯乙酸。这五种化合物抑制了紧密连接（zoo-1）和异源物代谢（ges-1）基因的表达，表明这两个基因可能在卤乙酸诱导的肠道毒性中至关重要。这项工作有助于增进对卤乙酸毒性的现有认识，并为理解其肠道毒性机制提供依据。
