Center for Water and Health, Key Lab of Health Technology Assessment, National Health Commission, Key Laboratory of Public Health and Safety, Ministry of Education, Department of Environmental Health, School of Public Health, Fudan University, P.O. Box 249, Yi Xue Yuan Road 138, Shanghai, 200032, China.
Center for Water and Health, Key Lab of Health Technology Assessment, National Health Commission, Key Laboratory of Public Health and Safety, Ministry of Education, Department of Environmental Health, School of Public Health, Fudan University, P.O. Box 249, Yi Xue Yuan Road 138, Shanghai, 200032, China; Key Laboratory of Public Health and Safety, Ministry of Education, Department of Hygienic Chemistry, School of Public Health, Fudan University, P.O. Box 122, Yi Xue Yuan Road 138, Shanghai, 200032, China.
Chemosphere. 2022 Apr;292:133496. doi: 10.1016/j.chemosphere.2021.133496. Epub 2022 Jan 3.
Comprehensive enrichment of contaminants in drinking water is an essential step for accurately determining exposure levels of contaminants and testing their biological effects. Traditional methods using a single absorbent for enriching contaminants in water might not be adequate for complicated matrices with different physical-chemical profiles. To examine this hypothesis, we used an integrated enrichment system that had three sequential stages-XAD-2 resin, poly (styrene-divinylbenzene) and activated charcoal to capture organic pollutants and disinfection by-products (DBPs) from drinking water in Shanghai. Un-adsorbed Organic Compounds in Eluates (UOCEs) named UOCEs-A, -B, and-C following each adsorption stage were determined by gas chromatography-mass spectrometry to evaluate adsorption efficiency of the enrichment system. Meanwhile, biological effects such as cytotoxicity, effects on reactive oxygen species (ROS) generation and glutathione (GSH) depletion were determined in human LO2 cells to identify potential adverse effects on exposure to low dose contaminants. We found that poly-styrene-divinylbenzene (PS-DVB) and activated charcoal (AC) could still partly collect UOCEs-A and-B that the upper adsorption column incompletely captured, and that potential carcinogens like 2-naphthamine were present in all eluates. UOCEs-A at (1-4000), UOCEs-B at (1000-4000), and UOCEs-C at (2400-4000) folds of the actual concentrations had significant cytotoxicity to LO2 cells. Additionally, ROS and GSH change in cells treated with UOCEs indicated the potential for long-term effects of exposure to some mixtures of contaminants such as DBPs at low doses. These results suggested that an enriching system with a single adsorbent would underestimate the exposure level of pollutants and the biological effects of organic pollutants from drinking water. Effective methods for pollutants' enrichment and capture of drinking water should be given priority in future studies on accurate evaluation of biological effects exposed to mixed pollutants via drinking water.
全面富集饮用水中的污染物是准确确定污染物暴露水平并测试其生物效应的重要步骤。传统的使用单一吸附剂富集水中污染物的方法可能不足以处理具有不同物理化学特征的复杂基质。为了检验这一假设，我们使用了一种集成的富集系统，该系统有三个连续的阶段——XAD-2 树脂、聚苯乙烯-二乙烯基苯和活性炭，从上海的饮用水中捕获有机污染物和消毒副产物（DBPs）。通过气相色谱-质谱法测定洗脱液中未被吸附的有机化合物（UOCEs），根据每个吸附阶段命名为 UOCEs-A、-B 和-C，以评估富集系统的吸附效率。同时，在人 LO2 细胞中测定细胞毒性、对活性氧（ROS）生成和谷胱甘肽（GSH）耗竭的影响等生物效应，以确定低剂量污染物暴露的潜在不良影响。我们发现，聚苯乙烯-二乙烯基苯（PS-DVB）和活性炭（AC）仍可部分收集上吸附柱不完全捕获的 UOCEs-A 和-B，并且所有洗脱液中都存在 2-萘胺等潜在的致癌物质。实际浓度的 1-4000 倍的 UOCEs-A、1000-4000 倍的 UOCEs-B 和 2400-4000 倍的 UOCEs-C 对 LO2 细胞均具有显著的细胞毒性。此外，用 UOCEs 处理后的细胞中 ROS 和 GSH 的变化表明，在低剂量下，一些污染物混合物（如 DBPs）的暴露可能会产生长期影响。这些结果表明，使用单一吸附剂的富集系统会低估污染物的暴露水平和饮用水中有机污染物的生物效应。在未来的研究中，应优先考虑有效富集和捕获饮用水中污染物的方法，以便更准确地评估通过饮用水暴露于混合污染物的生物效应。
