ENVIRONMENTAL RESEARCH
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2025
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IF 7.7
Lingmin Jin,Yuchen Lu,Jiawei Huang,Jiangmin Liu,Xiaoxuan Wei,Guangcai Ma,Haiying Yu
The nitrogen-contained disinfection by-products, halonitromethanes (HNMs), are known for their high cytotoxicity and genotoxicity. Although HNMs can be metabolized by cytochrome P450 enzymes (P450s), the specific mechanism has remained unclear. To shed light on this, density functional theory (DFT) calculations were performed to elucidate the potential oxidative P450-catalytic activation of the nine HNMs. Our findings reveal that active species of P450s (Cpd I) predominantly react with halogen-substituted nitromethanes via hydrogen abstraction and bromine atom abstraction, rather than chlorosylation. As a result of these reactions, oxidized HNMs are produced and can undergo further hydrolysis, leading to nitro-formaldehyde, nitro formyl halogen, halogen hydride, hypobromous acid, and nitroformic acid. To experimentally validate the computational predictions, in vitro experiments were conducted on five typical nitromethanes using human liver microsomes and the results reveal that DCNM, BCNM and DBCNM form nitroformyl chlorine (NO 2 CClO), while BCNM, DBNM and TBNM are transferred into nitroformyl bromide (NO 2 CBrO). Nitroformic acid is also identified as a metabolite in the TBNM metabolism reaction. Toxicity assessment reveals that metabolic transformation leads to an overall reduction in the ecological toxicity. However, metabolites showed similar toxicity to Fathead minnow and even higher acute toxicity to rat, as well as larger probability of hERG inhibition effects than HNMs, underscoring the need for caution in health risk assessment. By integrating in silico and in vitro approaches, this work has provided a comprehensive understanding of the metabolism of HNMs and offered potential toxicity data basis of these compounds.
研究领域:
环境毒理学
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生物化学
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计算化学
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药理学
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水处理化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Water Supply
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2013
·Vol. 13
·期 5
·1257-1264
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IF 0
Huang F. Q.,Ruan M. Y.,Yan J. D.,Hong H. C.,Lin H. J.,Xiong Y. J.
Halonitromethanes (HNMs) in drinking water are increasingly becoming a public concern due to their high health risks, so development of a sensitive method for their analysis has become a priority. Liquid–liquid extraction (LLE) method is dominantly used in current studies regarding HNMs. However the sensitivity is far from ideal. The present study aims to investigate the factors that may influence the extraction efficiency during HNM analysis by LLE method, and as a result develop a more sensitive extraction method for HNM determination. Results showed that the dose of sodium sulfate exerted the most significant influence, followed by copper sulfate, while the pH and manual shaking times have little effect. Under the suitable conditions (for extracting HNMs in 45 mL water: pH = 3.5–5, CuSO 4 = 1.0 g, Na 2 SO 4 = 6 g, shaking times = 120–180), the correlation coefficients ( r ) of the calibration curves for nine HNMs were all more than 0.9925. The method detection limit (MDL) ranged from 0.017 to 0.217 μg L −1 with an average of 0.076 μg L −1 , which was dominantly lower than the method reported. The recovery (spiked blank samples: 98–108%; spiked tap water: 81–120%) and precision (relative standard deviation: 0.46–6.72) also showed good reliability and reproducibility of the method. Finally, the developed method was applied to the determination of HNMs in real water samples.
✓ 已验证
DOI
SCIENCE OF THE TOTAL ENVIRONMENT
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2012
·
IF 3.286
Huachang Hong,Yujing Xiong,Mengyong Ruan,Fanglei Liao,Hongjun Lin,Yan Liang
The formations of THMs, HAAs, and HNMs from chlorination and chloramination of water from Jinlan Reservoir were investigated in this study. Results showed that monochloramine rather than chlorine generally resulted in lower concentration of DBPs, and the DBPs formation varied greatly as the treatment conditions changed. Specifically, the yields of THMs, HAAs and HNMs all increased with the high bromide level and high disinfectant dose both during chlorination and chloramination. The longer reaction time had a positive effect on the formation of THMs, HAAs and HNMs during chlorination and HNMs during chloramination. However, no time effect was observed on the formation of THMs and HAAs during chloramination. An increase in pH enhanced the levels of THMs and HNMs upon chlorination but reduced levels of HNMs upon chloramination. As for the THMs in chloramination and HAAs in chlorination and chloramination, no obvious pH effect was observed. The elevated temperature significantly increased the yields of THMs during chlorination and HNMs during chloramination, but has no effect on THMs and HAAs yields during chloramination. In the same temperature range, the formation of HAAs and HNMs in chlorination showed a first increasing and then a decreasing trend. In chloramination study, addition of nitrite markedly increased the formation of HNMs but had little impact on the formation of THMs and HAAs. While in chlorination study, the presence of high nitrite levels significantly reduced the yields of THMs, HAAs and HNMs. Range analysis revealed that the bromide and disinfectant levels were the major factors affecting THMs, HAAs and HNMs formation, in both chlorination and chloramination. Finally, comparisons of the speciation of mono-halogenated, di-halogenated, tri-halogenated HAAs and HNMs between chlorination and monochloramination were also conducted, and factors influencing the speciation pattern were identified.
研究领域:
环境科学
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公共卫生
✓ 已验证
产品关联
DOI
PubMed
高影响因子
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