Chlorination studies of free and combined amino acids
TL;DR: In this article, the authors have shown that the reactivity of free amino acids with chlorine is related to their structure and that the amide linkage does not participate significantly in the chlorine demand of polypeptides, and does not seem to be TOX precursor.
About: This article is published in Water Research.The article was published on 1994-12-01. It has received 204 citations till now. The article focuses on the topics: Amino acid & Chlorine.
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TL;DR: In this article, the formation pathways for nitrogenous disinfection byproducts (N-DBPs) associated with chlorine, ozone, chlorine dioxide, UV, and chloramine disinfection are critically reviewed.
Abstract: Interest in the formation of nitrogenous disinfection byproducts (N-DBPs) has increased because toxicological research has indicated that they are often more genotoxic, cytotoxic, or carcinogenic than many of the carbonaceous disinfection byproducts (C-DBPs) that have been a focus for previous research. Moreover, population growth has forced utilities to exploit source waters impaired by wastewater effluents or algal blooms. Both waters feature higher levels of organic nitrogen, that might serve as N-DBP precursors. Utilities are exploring new disinfectant combinations to reduce the formation of regulated trihalomethanes and haloacetic acids. As some of these new combinations may promote N-DBP formation, characterization of N-DBP formation pathways is needed. Formation pathways for halonitroalkanes, halonitriles, haloamides, and N-nitrosamines associated with chlorine, ozone, chlorine dioxide, UV, and chloramine disinfection are critically reviewed. Several important themes emerge from the review. First, ...
580 citations
TL;DR: Improved knowledge that bromine reacts faster and substitutes more efficiently than chlorine will be useful in developing strategies to control disinfection by-product formation during water treatment.
480 citations
TL;DR: Algal organic matter, including extracellular organic matter (EOM) and intracellularorganic matter (IOM), was characterized and the formation of a variety of disinfection by-products (DBPs) in chlorination and chloramination of EOM, IOM and algal cells was evaluated.
336 citations
Cites background from "Chlorination studies of free and co..."
...Amide linkages in combined amino acids do not participate significantly in the chlorine demand (Hureiki et al., 1994)....
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...8wasdrawnto illustrate the reactionpathways of these reactions, based on the general agreement in the literature (Hawkins et al., 2003; Hureiki et al., 1994; Scully et al., 1994; JooandMitch, 2007;Yanget al., 2010) and the results from this study, with amino acids taken as the model org-N in algal…...
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TL;DR: The degradation of extracellular microcystin by chlorine was found to be dependent upon the pH, chlorine exposure, and the presence of cyanobacterial cells, which is within the range of normal disinfection practices.
Abstract: The proliferation of cyanobacteria in drinking water sources is problematic for water authorities as they can interfere with water treatment processes. Studies have shown that oxidants such as chlorine can enhance the coagulation of cyanobacteria; however, chlorine can potentially lyse cyanobacterial cells, releasing toxic metabolites. Chlorine also has the potential to effectively degrade these toxins. This study evaluated the effect of chlorine on the cell integrity of toxic Microcystis aeruginosa in reservoir water using flow cytometry. In addition, the effect of chlorine on the subsequent release and degradation of microcystin toxins was systematically assessed. Cell lysis occurred at chlorine exposure values between 7 and 29 mg min/L, which is within the range of normal disinfection practices. Intracellular toxin was shown to be released from damaged cells at a rate three times faster than it was degraded by chlorine. The degradation of extracellular microcystin by chlorine was found to be dependent ...
257 citations
TL;DR: In this paper, the importance of identifying algae-derived sources of organic carbon (DOC) in water supplies and removing such sources in water treatment has been discussed, as well as the need to remove such sources from water supply.
Abstract: Algae (green, blue–green, and diatom) grown in inorganic media produced particulate and dissolved organic carbon (DOC). DOC produced by a green-alga contains 25% hydrophobic acids. DOC from all algae had specific ultraviolet absorbance values less than 2.0 m−1 (mg∕L)−1 . Algae-produced DOC was biologically labile; greater than 60% degraded in bioreactors within 5 days. The biodegradable material likely included carbohydrates, amino acids, and amino sugars, which were present in hydrophobic acid isolates. Chlorination of algal DOC formed disinfection by-products; DOC from the green alga, Scenedesmus quadricauda, produced chloroform [0.53 micromole per mg carbon (μmol∕mg C)] , dichloroacetic acid (0.27 μmol∕mg C) , and trichloroacetic acid (0.14 μmol∕mg C) . This work complements other studies, which focused on algal total organic carbon (DOC and cellular material), and clearly demonstrates the importance of identifying algae-derived sources of DOC in water supplies and removing such DOC in water treatment ...
256 citations
References
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156 citations
TL;DR: HOCl by oxidative decarboxylation converts several α-amino acids into a mixture of the corresponding nitriles (major) and aldehydes (minor product) and chlorination of the ring of tyrosine was observed.
147 citations
TL;DR: Evaluation de la reaction du sulfite de sodium avec des composes organiques halogenes specifiques formes au cours de la chloration d'eau potable as mentioned in this paper.
Abstract: Evaluation de la reaction du sulfite de sodium avec des composes organiques halogenes specifiques formes au cours de la chloration d'eau potable
121 citations
TL;DR: A partir de la connaissance des donnees cinetiques de la degradation de composes complexes (acide fulvique, proteine), il est possible de determiner pour tout melange de ces composes, the part apportee par chacun a la consommation en chlore observee sur le melange.
77 citations