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Showing 1 to 20 of 33 for “"haloacetic acids"”.
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Toxic effects on model mammalian cells by monohalogenated disinfection byproducts: haloacetic acids and haloacetonitriles
… with halogen and nitrogenous functional groups, haloacetic acids (HAAs) and haloacetonitriles (HANs) were selected as representative carbonaceous and nitrogenous DBPs to make comparisons in terms of genomic DNA damage induction, repair efficiency of induced DNA lesions, and cell cycle alteration …
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The Effect of Predisinfection with Chlorine Dioxide on the Formation of Haloacetic Acids and Trihalomethanes in a Drinking Water Supply
… Protection Agency regulations governing haloacetic acids (HAAs) and trihalomethanes (THMs), the Blacksburg, Christiansburg, VPI (BCVPI) Water Authority in Radford, Virginia elected to eliminate prechlorination and replace it with preoxidation using chlorine dioxide (ClO2). Prior to …
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Toxicity mechanism of anthropogenic water contaminants: drinking water disinfection by-products (haloacetic acids) and particle associated contaminants from sealcoats (polyaromatic hydrocarbons) in lake sediments
… targets of all the regulated and non-regulated haloacetic acids (HAAs) water DBPs, ii) to differentiate among the toxicity mechanisms of mono-, di-, and triHAAs, iii) to evaluate the toxicity potential of chlorinated and chloraminated wastewater effluents, and iv) to evaluate the mutagenicity …
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Impacts of Sludge Volume and Sludge Age on Disinfection By-Product Formation in a Full-Scale Water Treatment Facility
… samples were tested for trihalomethanes and haloacetic acids at both ends of the sedimentation process to evaluate formation over the length of the basin. Sludge volume and other important water quality parameters were also measured at the time of sample collection. Statistical analyses were …
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Comparative Cytotoxicity and Genotoxicity of Drinking Water Disinfection by -Products
… genotoxicity of the DBPs showed that brominated haloacetic acids were more genotoxic than their chlorinated analogs in mammalian cells. The difference in the responses to DBPs by bacterial and mammalian cells suggests that the relative risks based on Salmonella alone should be questioned. The in …
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Determination of the Influence of Polyurethane Lining on Potable Water Quality
… Total solids (TS), odor, trihalomethanes (THMs), haloacetic acids (HAAs), and semivolatile organic carbons (SVOCs) were tested on days 1, 4, 9, and 14. The polyurethane lining had major impacts on pH, odor and haloacetic acids throughout the 30 day experiment. A 2-3 pH unit decrease to pH 6 was …
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The Occurrence and Control of Disinfection By-Products (DBPs) in Two Water Treatment Plants Utilizing the Same Source
… which the majority produced by chlorination were haloacetic acids (HAAs), within the HAAs, dichloroacetic acid (DCAA) and trichloroacetic acid (TCAA) were the dominant members. Concern over potential health effect led the U.S. Environmental Protection Agency (USEPA) to set a maximum contaminant …
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Development of membrane extraction techniques for water quality analysis
… compounds was demonstrated using this technique. Haloacetic acids are a major group of harmful disinfection by-products in potable water generated during chlorination. A simple, economical, and highly efficient method was developed for the determination of all nine haloacetic acids in water. The …
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PHOTOELECTROCATALYTIC OXIDATION OF MUNICIPAL REVERSE OSMOSIS CONCENTRATE
… byproducts (DBPs), trihalomethanes and haloacetic acids. The results show that PEC could be an economically viable alternative for ROC treatment with proper control of DBPs formation.
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Gas chromatographic-electron capture analysis of disinfection byproducts from the chlorination of swimming pools and lake water
… another group of halogenated compounds, known as haloacetic acids. Results showed that the methylation performed well however, the diazomethane methylated many compounds that were not being studied which interfered with the compounds that were being studied; The final portion of this research …
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Reduction of Disinfection Byproduct-associated Toxicity by Adjustment of Distribution System pH
… HAN hydrolysis to HAMs and HAM hydrolysis to haloacetic acids (HAAs). Because the ranked toxicity of these groups is HAN > HAM > HAA, such a hydrolysis scheme would result in reduced sample toxicity. The formation and degradation of HANs and HAMs was examined in conventionally treated surface …
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Drinking water disinfection by-products detection, formation and the precursors removal study
"Haloacetic acids (HAAs) and trihalomethanes (THMs) are two groups of commonly found disinfection by-products (DBPs). Iodinated THMs and HAAs were observed after disinfection of water containing high level of iodide and are proved to be more toxic than their corresponding chlorinated and brominated …
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Management of disinfection byproduct production in small drinking water systems
… in drinking water are trihalomethanes (THMs) and haloacetic acids (HAAs). The objective of this research was to better understand how the water treatment processes employed at four smaller municipal water treatment utilities affects THM and HAA formation by measuring the removal of organic …
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Evaluation of Soil Aquifer Treatment in a Lab Scale Soil Column Experiment
… nitrite, bromate, trihalomethane (THM), haloacetic acids (HAA), organic carbon) and unregulated contaminants of concern that affect drinking water quality. Effective pathogen removal was observed with 6 to 7-log removals of MS2 and E. coli and 3 to 5-log removals of microbeads, used as a …
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Analysis and occurrence of disinfection by-products in fresh and salt water
<p>"Haloacetic acids, trihalomethanes, and bromate are important toxic water disinfection by-products (DBPs) that the US Environmental Protection Agency (USEPA) regulates in drinking water. Iodoacetic acids and halonitromethanes (HNMs) are the unregulated emerging DBPs that have been recently found …
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Formation of (halo)acetamides and (halo)acetonitriles from the reaction of monochloramine and (halo)acetaldehydes in water
… that include four trihalomethanes and five haloacetic acids. However, recent research suggests that unregulated nitrogen-containing DBPs formed by combined chlorine, such as haloacetonitriles and haloacetamides, might be more toxic than regulated DBPs. Monochloramine has been shown to react …
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Water Quality, Aesthetic, and Corrosion Inhibitor Implications of Newly Installed Cement Mortar Lining Used to Rehabilitate Drinking Water Pipelines
… increase in the formation of regulated haloacetic acids or trihalomethanes. Significant levels of aluminum (< 700 ug/L) and chromium (< 75 ug/L) were released at various times during the test period but their concentrations did not exceed USEPA water quality standards. Cement odor …
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Impact of an Epoxy Pipe Lining Material on Distribution System Water Quality
… was leached (2.6-6.2 mg/L), trihalomethanes and haloacetic acids were formed (both < 15 ug/L), Bisphenol-A, an endocrine disrupter, was detected (< 35 ug/L), and odor was reported by panelists at a moderate intensity and described as sweet/chemical/burning/chlorinous. Impacts were much less after …
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Disinfection by-products and prenatal development
… teratogenic outcomes. Exposure to high doses of haloacetic acids (HAAs), the second most commonly occurring group of DBPs, causes cardiovascular and orofacial malformations, such as cleft palate, in laboratory studies. Human studies have focused primarily on low-dose exposures to THMs. Most …
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Wildfire Impacts on Water Quality and Implications for Disinfection Byproduct Formation
… (DBPs) known as trihalomethanes (THMs) and haloacetic acids (HAAs), though questions remain about changes in the reactivity of fire-affected DOM to form these. Less attention has been paid to unregulated nitrogenous DBPs (N-DBPs), such as haloacetonitriles (HANs), and currently, no studies …
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