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Effect of spring runoff on 2,6-dichloro-1,4-benzoquinone formation during water treatment
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作者 K.N.Minh Chau Nicholas J.P.Wawryk +3 位作者 Qiming Shen caley b.craven Kristin Carroll Xing-Fang Li 《Journal of Environmental Sciences》 2025年第7期182-190,共9页
This study investigated the impacts of spring runoff on the formation of halobenzoquinones(HBQs)and their correlation with common water quality parameters(WQPs)and aromatic amino acids(AAs)in source water.Source water... This study investigated the impacts of spring runoff on the formation of halobenzoquinones(HBQs)and their correlation with common water quality parameters(WQPs)and aromatic amino acids(AAs)in source water.Source water and treated water samples were collected at two drinking water treatment plants in 2021,2022,and 2023.HBQs and aromatic AAs were analyzed using solid phase extraction with high performance liquid chromatography–tandem mass spectrometry methods.The only HBQs detected in treated water were 2,6-dichloro-1,4-benzoquinone(DCBQ)and hydroxy–DCBQ(OH-DCBQ).The concentration of DCBQ was 3-4 times higher during spring runoff events than during non-spring-runoff periods,suggesting the impact of spring runoff on the formation of DCBQ.The DCBQ concentrations in finished water positively correlated with the color,dissolved organic carbon,total organic nitrogen,and specific ultraviolet absorbance WQPs of source water in 2021 and 2022.The temporal trend of the total aromatic AAs determined in source water was strongly and positively correlated to DCBQ in finished water.Finally,there was a significant positive correlation between the concentration of DCBQ determined immediately following the addition of chlorine and the presence of its transformation product,OH-DCBQ,in finished water.The results also showed that powdered activated carbon can remove some of the HBQ precursors in the sourcewater to reduce DCBQ formation.This study demonstrated that WQPs and aromatic AAs are useful indicators for the removal of precursors to reduce HBQ formation during drinking water treatment. 展开更多
关键词 Halobenzoquinones Water treatment Amino acids Natural organic matter(NOM) Spring runoff Hydroxylated halobenzoquinones
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Pesticides and trace elements in cannabis:Analytical and environmental challenges and opportunities 被引量:5
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作者 caley b.craven Nicholas Wawryk +2 位作者 Ping Jiang Zhongshan Liu Xing-Fang Li 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2019年第11期82-93,共12页
Cannabis is increasingly used for both medicinal and recreational purposes with an estimate of over 180 million users annually.Canada has recently legalized cannabis use in October 2018,joining several states,in the U... Cannabis is increasingly used for both medicinal and recreational purposes with an estimate of over 180 million users annually.Canada has recently legalized cannabis use in October 2018,joining several states,in the United States of America (e.g.,Colorado,California,and Oregon) and a few other countries.A variety of cannabis products including dry flowers,edibles,and oil products are widely consumed.With high demand for cannabis products worldwide,the quality of cannabis and its related products has become a major concern for consumer safety.Various guidelines have been set by different countries to ensure the quality,safety,and efficacy of cannabis products.In general,these guidelines require control of contaminants including pesticides,toxic elements,mycotoxins,and pathogens,as well as residual solvents in regard to cannabis oil.Accordingly,appropriate analytical methods are required to determine these contaminants in cannabis products for quality control.In this review,we focus on the current analytical challenges and method development for detection of pesticides and toxic elements in cannabis to meet various guidelines. 展开更多
关键词 CANNABIS QA/QC CONTAMINANTS ANALYTICAL testing PESTICIDES Heavy metals Regulations
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New methods for identification of disinfection byproducts of toxicological relevance: Progress and future directions 被引量:4
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作者 Nicholas J.P.Wawryk caley b.craven +1 位作者 Lindsay K.Jmaiff Blackstock Xing-Fang Li 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2021年第1期151-159,共9页
Disinfection byproducts(DBPs)represent a ubiquitous source of chemical exposure in disinfected water.While over 700 DBPs have been identified,the drivers of toxicity remain poorly understood.Additionally,ever evolving... Disinfection byproducts(DBPs)represent a ubiquitous source of chemical exposure in disinfected water.While over 700 DBPs have been identified,the drivers of toxicity remain poorly understood.Additionally,ever evolving water treatment practices have led to a continually growing list of DBPs.Advancement of analytical technologies have enabled the identification of new classes of DBPs and the quantification of these chemically diverse sets of DBPs.Here we summarize advances in new workflows for DBP analysis,including sample preparation,chromatographic separation with mass spectrometry(MS)detection,and data processing.To aid in the selection of techniques for future studies,we discuss necessary considerations for each step in the strategy.This review focuses on how each step of a workflow can be optimized to capture diverse classes of DBPs within a single method.Additionally,we highlight new MS-based approaches that can be powerful for identifying novel DBPs of toxicological relevance.We discuss current challenges and provide perspectives on future research directions with respect to studying new DBPs of toxicological relevance.As analytical technologies continue to advance,new strategies will be increasingly used to analyze complex DBPs produced in different treatment processes with the aim to identify potential drivers of toxicity. 展开更多
关键词 Water disinfection byproducts(DBPs) Emerging contaminants Mass spectrometry CHROMATOGRAPHY Nontargeted analysis Toxicity drivers
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HDPairFinder:A data processing platform for hydrogen/deuterium isotopic labeling-based nontargeted analysis of trace-level amino-containing chemicals in environmental water
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作者 Tingting Zhao Kristin Carroll +5 位作者 caley b.craven Nicholas J.P.Wawryk Shipei Xing Jian Guo Xing-Fang Li Tao Huan 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2024年第2期583-593,共11页
The combination of hydrogen/deuterium(H/D)formaldehyde-based isotopic methyl labeling with solid-phase extraction and high-performance liquid chromatography–high resolution mass spectrometry(HPLC-HRMS)is a powerful a... The combination of hydrogen/deuterium(H/D)formaldehyde-based isotopic methyl labeling with solid-phase extraction and high-performance liquid chromatography–high resolution mass spectrometry(HPLC-HRMS)is a powerful analytical solution for nontargeted analysis of trace-level amino-containing chemicals in water samples.Given the huge amount of chemical information generated in HPLC-HRMS analysis,identifying all possible H/Dlabeled amino chemicals presents a significant challenge in data processing.To address this,we designed a streamlined data processing pipeline that can automatically extract H/D-labeled amino chemicals from the raw HPLC-HRMS data with high accuracy and efficiency.First,we developed a cross-correlation algorithm to correct the retention time shift resulting from deuterium isotopic effects,which enables reliable pairing of H-and D-labeled peaks.Second,we implemented several bioinformatic solutions to remove false chemical features generated by in-source fragmentation,salt adduction,and natural13C isotopes.Third,we used a data mining strategy to construct the AMINES library that consists of over 38,000 structure-disjointed primary and secondary amines to facilitate putative compound annotation.Finally,we integrated these modules into a freely available R program,HDPairFinder.R.The rationale of each module was justified and its performance tested using experimental H/D-labeled chemical standards and authentic water samples.We further demonstrated the application of HDPairFinder to effectively extract N-containing contaminants,thus enabling the monitoring of changes of primary and secondary N-compounds in authentic water samples.HDPairFinder is a reliable bioinformatic tool for rapid processing of H/D isotopic methyl labeling-based nontargeted analysis of water samples,and will facilitate a better understanding of N-containing chemical compounds in water. 展开更多
关键词 Isotope labeling Nontargeted analysis Reactive N-compounds HPLC-HRMS Source water
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