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Li J, Shi W, Liu Y, Li J, Chen J, Hu C, Dong H. Revealing the impact of sample enrichment method on concentration and cytotoxicity of volatile disinfection byproducts in drinking water: A quantitative study for liquid-liquid extraction. WATER RESEARCH 2024; 266:122370. [PMID: 39236505 DOI: 10.1016/j.watres.2024.122370] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2024] [Revised: 08/24/2024] [Accepted: 08/31/2024] [Indexed: 09/07/2024]
Abstract
Liquid-liquid extraction (LLE) combined with the N2 blow-down method is a promising tool for bioanalysis of drinking water. However, detailed information on which disinfection byproduct (DBP) classes are retained in LLE extracts is currently unavailable. In this study, the recovery of seven classes of volatile DBPs and total adsorbable organic halogens (TOX) during the LLE method, combined with three common N2 blow-down methods, for bioanalysis in real tap water was analyzed at a 2-L scale, along with their corresponding cytotoxicity. The total concentration of seven classes of volatile DBPs in drinking water in Suzhou ranged from 64.6 to 83.0 µg/L, with the majority contributed by trihalomethanes (THMs: 59.9 µg/L), haloaldehydes (HALs: 5.4 µg/L), haloacetamides (HAMs: 3.4 µg/L), and haloacetonitriles (HANs: 3.2 µg/L). During the LLE - N2 blow-down process for bioanalysis, about 69-85 % of targeted volatile DBPs and 64-75 % of TOX were lost, respectively. Seven classes of volatile DBPs accounted for 52.8-64.3 % and 23.8-61.3 % of TOX in tap water and LLE - N2 blow-down samples, respectively, suggesting that targeted aliphatic DBPs are the key contributors to TOX. Furthermore, although LLE - solvent exchange had a better recovery performance than other N2 blow-down methods, the recoveries of volatile DBPs using this method were still not ideal. For example, HALs and HAMs had a slightly better recovery (>50 %), while most volatile DBPs had a poor recovery, including iodo-trihalomethanes (I-THMs, 0 %), haloketones (28 %), THMs (26 %), halonitromethanes (33 %), and HANs (38 %). During LLE - solvent exchange, 31 % and 36 % of targeted DBPs and TOX, respectively, in real tap water can be retained, which shows better performance than non-ionic macroporous copolymers (XAD). More importantly, the water volume required in this method for cytotoxicity analysis is 2 L, which greatly reduces the burden of water sample collection, transport, and pre-treatment compared to XAD (which typically requires 5 or 10 L). In general, this paper reveals the fate of volatile DBPs during LLE - N2 blow-down and indicates that LLE - solvent exchange is a good substitute for the XAD method in bioanalysis.
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Affiliation(s)
- Jiafu Li
- Department of Occupational and Environmental Health, School of Public Health, Soochow University, Suzhou 215123, China; Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Wenshan Shi
- Department of Occupational and Environmental Health, School of Public Health, Soochow University, Suzhou 215123, China
| | - Yuting Liu
- Department of Occupational and Environmental Health, School of Public Health, Soochow University, Suzhou 215123, China
| | - Junlin Li
- Department of Occupational and Environmental Health, School of Public Health, Soochow University, Suzhou 215123, China
| | - Jingsi Chen
- Department of Occupational and Environmental Health, School of Public Health, Soochow University, Suzhou 215123, China
| | - Chengzhi Hu
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100101, China
| | - Huiyu Dong
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100101, China.
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Li S, Wu S, Cheng X, Dong H, Qiang Z, Xu D. Adsorption, boiling or membrane filtration for disinfection by-product removal: How to make our drinking water safer? THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 912:169468. [PMID: 38143003 DOI: 10.1016/j.scitotenv.2023.169468] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Revised: 11/25/2023] [Accepted: 12/16/2023] [Indexed: 12/26/2023]
Abstract
Disinfection by-products (DBPs) generated in drinking water have become a global concern due to their potential harm to human health. Nevertheless, there are few studies about different point-of-use water treatments in household drinking water. The study aims to compare the effectiveness of three point-of-use water treatments: adsorption, boiling, and membrane filtration. The experimental results showed that the initial average concentration of volatile DBPs and non-volatile DBPs for tap water were 63.71 μg/L and 6.33 μg/L. The removal efficiency of DBPs for adsorption which were 75.6 % (the filter volumes from 0 L to 20 L) and 45.4 % (the filter volumes from 20 L to 50 L) during the service life of the filter element (50 L). Boiling had a high removal efficiency for volatile DBPs like trihalomethanes (THMs), haloacetaldehydes (HALs), haloacetonitriles (HANs), and haloketones (HKs) (90.5 %, 100 %, 100 %, and 100 %, respectively). However, boiling had a low removal efficiency which was 15 % in removing non-volatile DBPs like haloacetic acids (HAAs). Membrane filtration had a middle removal efficiency for THMs, HAAs, HALs, HKs, and HANs (45.3 %, 75.2 %, 46.5 %, 47.6 %, and 100 %, respectively). Through analysis of the correlation between dissolved organic matter (DOM) removal efficacy and DBP removal efficiency, it was found that the strongest correlation was observed between UV254 and DBP removal efficiency. Boiling showed a lower estimated cytotoxicity of DBPs compared to adsorption and membrane filtration. Cancer risk assessment of DBPs was below the specified risk range for three point-of-use water treatments. This study provides a reference for choosing point-of-use water treatments in household drinking water.
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Affiliation(s)
- Shaoqiu Li
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; School of Chemical and Environmental Engineering, China University of Mining and Technology, Beijing 100083, China
| | - Shengnian Wu
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; School of Chemical and Environmental Engineering, China University of Mining and Technology, Beijing 100083, China
| | - Xiaoyu Cheng
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Huiyu Dong
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Zhimin Qiang
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Dongyao Xu
- School of Chemical and Environmental Engineering, China University of Mining and Technology, Beijing 100083, China
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