Base de dados : MEDLINE
Pesquisa : D01.210 [Categoria DeCS]
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  1 / 1327 MEDLINE  
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[PMID]:28851159
[Au] Autor:Acharjee TC; Jiang Z; Haynes RD; Lee YY
[Ad] Endereço:Department of Chemical Engineering, Auburn University, 212 Ross Hall, Auburn, AL 36849, USA; Alabama Center for Paper & Bioresource Engineering, Auburn University, 356 Ross Hall, Auburn, AL 36849, USA.
[Ti] Título:Evaluation of chlorine dioxide as a supplementary pretreatment reagent for lignocellulosic biomass.
[So] Source:Bioresour Technol;244(Pt 1):1049-1054, 2017 Nov.
[Is] ISSN:1873-2976
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Chlorine dioxide (ClO ) is a bleaching reagent used in paper industry. Two different types of pretreatment methods were investigated incorporating ClO as a secondary reagent: (a) alkaline followed by ClO treatment; (b) dilute-sulfuric acid followed ClO treatment. In these methods, ClO treatment has shown little effect on delignification. Scheme-a has shown a significant improvement in enzymatic digestibility of glucan far above that treated by ammonia alone. On the contrary, dilute-acid followed by ClO treatment has shown negative effect on the enzymatic hydrolysis. The main factors affecting the enzymatic hydrolysis are the changes of the chemical structure of lignin and its distribution on the biomass surface. ClO treatment significantly increases the carboxylic acid content and reduces phenolic groups of lignin, affecting hydrophobicity of lignin and the H-bond induced association between the enzyme and lignin. This collectively led to reduction of unproductive binding of enzyme with lignin, consequently increasing the digestibility.
[Mh] Termos MeSH primário: Biomassa
Compostos Clorados
Lignina
Óxidos
[Mh] Termos MeSH secundário: Hidrólise
Zea mays
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Chlorine Compounds); 0 (Oxides); 11132-73-3 (lignocellulose); 8061YMS4RM (chlorine dioxide); 9005-53-2 (Lignin)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171025
[Lr] Data última revisão:
171025
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170831
[St] Status:MEDLINE


  2 / 1327 MEDLINE  
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[PMID]:28774629
[Au] Autor:Han J; Zhang X; Liu J; Zhu X; Gong T
[Ad] Endereço:Environmental Engineering Program, Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology, Hong Kong, China.
[Ti] Título:Characterization of halogenated DBPs and identification of new DBPs trihalomethanols in chlorine dioxide treated drinking water with multiple extractions.
[So] Source:J Environ Sci (China);58:83-92, 2017 Aug.
[Is] ISSN:1001-0742
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Chlorine dioxide (ClO ) is a widely used alternative disinfectant due to its high biocidal efficiency and low-level formation of trihalomethanes and haloacetic acids. A major portion of total organic halogen (TOX), a collective parameter for all halogenated DBPs, formed in ClO -treated drinking water is still unknown. A commonly used pretreatment method for analyzing halogenated DBPs in drinking water is one-time liquid-liquid extraction (LLE), which may lead to a substantial loss of DBPs prior to analysis. In this study, characterization and identification of polar halogenated DBPs in a ClO -treated drinking water sample were conducted by pretreating the sample with multiple extractions. Compared to one-time LLE, the combined four-time LLEs improved the recovery of TOX by 2.3 times. The developmental toxicity of the drinking water sample pretreated with the combined four-time LLEs was 1.67 times higher than that pretreated with one-time LLE. With the aid of ultra-performance liquid chromatography/electrospray ionization-triple quadrupole mass spectrometry, a new group of polar halogenated DBPs, trihalomethanols, were detected in the drinking water sample pretreated with multiple extractions; two of them, trichloromethanol and bromodichloromethanol, were identified with synthesized standard compounds. Moreover, these trihalomethanols were found to be the transformation products of trihalomethanes formed during ClO disinfection. The results indicate that multiple LLEs can significantly improve extraction efficiencies of polar halogenated DBPs and is a better pretreatment method for characterizing and identifying new polar halogenated DBPs in drinking water.
[Mh] Termos MeSH primário: Compostos Clorados/análise
Desinfetantes/análise
Água Potável/análise
Óxidos/análise
Trialometanos/análise
Poluentes Químicos da Água/análise
[Mh] Termos MeSH secundário: Desinfecção/métodos
Água Potável/química
Halogenação
Extração Líquido-Líquido
Espectrometria de Massas por Ionização por Electrospray
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Chlorine Compounds); 0 (Disinfectants); 0 (Drinking Water); 0 (Oxides); 0 (Trihalomethanes); 0 (Water Pollutants, Chemical); 8061YMS4RM (chlorine dioxide)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170811
[Lr] Data última revisão:
170811
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170805
[St] Status:MEDLINE


  3 / 1327 MEDLINE  
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[PMID]:28774604
[Au] Autor:Kim D; Ates N; Kaplan Bekaroglu SS; Selbes M; Karanfil T
[Ad] Endereço:Department of Environmental Engineering and Earth Sciences, Clemson University, Anderson, SC 29625, USA.
[Ti] Título:Impact of combining chlorine dioxide and chlorine on DBP formation in simulated indoor swimming pools.
[So] Source:J Environ Sci (China);58:155-162, 2017 Aug.
[Is] ISSN:1001-0742
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:The main objective of this study was to assess the combined use of chlorine dioxide (ClO ) and chlorine (Cl ) on the speciation and kinetics of disinfection by-product (DBP) formation in swimming pools using synthetic pool waters prepared with a body fluid analog (BFA) and/or fresh natural water. At 1:25 (mass ratio) of ClO to Cl , there was no significant reduction in the formation of trihalomethanes (THMs) and haloacetic acids (HAAs) for both BFA solution and natural water compared to the application of Cl alone. When the mass ratio of ClO to Cl increased to 1:1, substantial decreases in both THMs and HAAs were observed in the natural water, while there was almost no change of DBP formations in the BFA solution. Haloacetonitriles and halonitromethanes levels in both water matrices remained similar. In the presence of bromide, the overall DBP formation increased in both BFA solution and natural water. For the DBP formation kinetics, after 72hr of contact time, very low formation of THMs and HAAs was observed for the use of ClO only. Compared to Cl control, however, applying the 1:1 mixture of ClO /Cl reduced THMs by >60% and HAAs by >50%. Chlorite was maintained below 1.0mg/L, while the formation of chlorate significantly increased over the reaction time. Finally, in a bench-scale indoor pool experiment, applying ClO and Cl simultaneously produced less THMs compared to Cl control and kept chlorite at <0.4mg/L, while HAAs and chlorate accumulated over 4-week operation period.
[Mh] Termos MeSH primário: Compostos Clorados/química
Cloro/química
Desinfetantes/química
Óxidos/química
Piscinas
Purificação da Água/métodos
[Mh] Termos MeSH secundário: Desinfecção/métodos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Chlorine Compounds); 0 (Disinfectants); 0 (Oxides); 4R7X1O2820 (Chlorine); 8061YMS4RM (chlorine dioxide)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170811
[Lr] Data última revisão:
170811
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170805
[St] Status:MEDLINE


  4 / 1327 MEDLINE  
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[PMID]:28628840
[Au] Autor:Bernard A; Sardella A; Voisin C; Dumont X
[Ad] Endereço:Louvain Centre for Toxicology and Applied Pharmacology, Institute of Experimental and Clinical Research (IREC), Catholic University of Louvain, Brussels, Belgium.
[Ti] Título:Nasal epithelium injury by chlorination products and other stressors predicts persistent sensitization to aeroallergens in young schoolchildren.
[So] Source:Environ Res;158:145-152, 2017 10.
[Is] ISSN:1096-0953
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: Allergic sensitization during childhood is a dynamic process with a substantial rate of remission. Factors influencing this process are largely unknown. METHODS: We conducted a two-year prospective study among 121 schoolchildren (mean age, 5.8 years; 64 boys). We measured urea, club cell protein (CC16), ß -microglobulin and albumin in nasal lavage fluid (NALF) and IgE to cat, pollen or house dust mite (HDM) in nasal mucosa fluid. RESULTS: Odds of persistent sensitization to any aeroallergen increased across baseline ascending tertiles of urea-adjusted ß -microglobulin or albumin and descending tertiles of albumin- or ß -microglobulin-adjusted CC16 (P-trend = 0.006, 0.02, 0.044 and 0.006, respectively). Persistent HDM sensitization also increased with baseline descending tertiles of raw or urea-adjusted CC16 (both P-trend = 0.007). Such strong associations were not observed with new-onset or remitted sensitization to any aeroallergen or with raw NALF concentrations of urea, albumin or ß -microglobulin. At baseline, house cleaning with bleach and chlorinated pool attendance emerged among the strongest and most consistent determinants of NALF biomarkers, being both associated with higher urea and lower CC16 in NALF. CONCLUSION: In young children, a defective nasal epithelium attributable to immaturity or stressors such as chlorination products is predictive of more persistent aeroallergen sensitization.
[Mh] Termos MeSH primário: Alérgenos/toxicidade
Compostos Clorados/toxicidade
Líquido da Lavagem Nasal/química
Mucosa Nasal/efeitos dos fármacos
[Mh] Termos MeSH secundário: Albuminas/metabolismo
Bélgica
Pré-Escolar
Feminino
Seres Humanos
Imunoglobulina E/metabolismo
Masculino
Mucosa Nasal/lesões
Estudos Prospectivos
Fatores de Risco
Uteroglobina/metabolismo
Microglobulina-2 beta/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Albumins); 0 (Allergens); 0 (Chlorine Compounds); 0 (SCGB1A1 protein, human); 0 (beta 2-Microglobulin); 37341-29-0 (Immunoglobulin E); 9060-09-7 (Uteroglobin)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:171120
[Lr] Data última revisão:
171120
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170620
[St] Status:MEDLINE


  5 / 1327 MEDLINE  
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[PMID]:28609731
[Au] Autor:Willach S; Lutze HV; Eckey K; Löppenberg K; Lüling M; Terhalle J; Wolbert JB; Jochmann MA; Karst U; Schmidt TC
[Ad] Endereço:University of Duisburg-Essen, Faculty of Chemistry, Instrumental Analytical Chemistry, Universitaetsstr. 5, D-45141 Essen, Germany.
[Ti] Título:Degradation of sulfamethoxazole using ozone and chlorine dioxide - Compound-specific stable isotope analysis, transformation product analysis and mechanistic aspects.
[So] Source:Water Res;122:280-289, 2017 Oct 01.
[Is] ISSN:1879-2448
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The sulfonamide antibiotic sulfamethoxazole (SMX) is a widely detected micropollutant in surface and groundwaters. Oxidative treatment with e.g. ozone or chlorine dioxide is regularly applied for disinfection purposes at the same time exhibiting a high potential for removal of micropollutants. Especially for nitrogen containing compounds such as SMX, the related reaction mechanisms are largely unknown. In this study, we systematically investigated reaction stoichiometry, product formation and reaction mechanisms in reactions of SMX with ozone and chlorine dioxide. To this end, the neutral and anionic SMX species, which may occur at typical pH-values of water treatment were studied. Two moles of chlorine dioxide and approximately three moles of ozone were consumed per mole SMX degraded. Oxidation of SMX with ozone and chlorine dioxide leads in both cases to six major transformation products (TPs) as revealed by high-resolution mass spectrometry (HRMS). Tentatively formulated TP structures from other studies could partly be confirmed by compound-specific stable isotope analysis (CSIA). However, for one TP, a hydroxylated SMX, it was not possible by HRMS alone to identify whether hydroxylation occurred at the aromatic ring, as suggested in literature before, or at the anilinic nitrogen. By means of CSIA and an analytical standard it was possible to identify sulfamethoxazole hydroxylamine unequivocally as one of the TPs of the reaction of SMX with ozone as well as with chlorine dioxide. H-abstraction and electron transfer at the anilinic nitrogen are suggested as likely initial reactions of ozone and chlorine dioxide, respectively, leading to its formation. Oxidation of anionic SMX with ozone did not show any significant isotopic fractionation whereas the other reactions studied resulted in a significant carbon isotope fractionation.
[Mh] Termos MeSH primário: Compostos Clorados
Óxidos
Ozônio
Sulfametoxazol
Poluentes Químicos da Água
[Mh] Termos MeSH secundário: Isótopos
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Chlorine Compounds); 0 (Isotopes); 0 (Oxides); 0 (Water Pollutants, Chemical); 66H7ZZK23N (Ozone); 8061YMS4RM (chlorine dioxide); JE42381TNV (Sulfamethoxazole)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171013
[Lr] Data última revisão:
171013
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170614
[St] Status:MEDLINE


  6 / 1327 MEDLINE  
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[PMID]:28388335
[Au] Autor:Johnson CY; Rocheleau CM; Hein MJ; Waters MA; Stewart PA; Lawson CC; Reefhuis J; National Birth Defects Prevention Study
[Ad] Endereço:a National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention , Cincinnati , Ohio.
[Ti] Título:Agreement between two methods for retrospective assessment of occupational exposure intensity to six chlorinated solvents: Data from The National Birth Defects Prevention Study.
[So] Source:J Occup Environ Hyg;14(5):389-396, 2017 05.
[Is] ISSN:1545-9632
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The wide variety of jobs encountered in population-based studies makes retrospective exposure assessment challenging in occupational epidemiology. In this analysis, two methods for estimating exposure intensity to chlorinated solvents are compared: rated (assigned by an expert rater) and modeled (assigned using statistical models). Estimates of rated and modeled intensities were compared for jobs held by mothers participating in the National Birth Defects Prevention Study with possible exposure to six chlorinated solvents: carbon tetrachloride, chloroform, methylene chloride, perchloroethylene, 1,1,1-trichloroethane, and trichloroethylene. For each possibly exposed job, an industrial hygienist assigned (1) an exposure intensity (rated intensity) and (2) determinants of exposure to be used in a statistical model of exposure intensity (modeled intensity). Of 12,326 reported jobs, between 31 (0.3%) and 746 (6%) jobs were rated as possibly exposed to each of the six solvents. Agreement between rated and modeled intensities was low overall (Spearman correlation coefficient range: -0.09 to 0.28; kappa range: -0.23 to 0.43). Although no air measurements were available to determine if rated or modeled estimates were more accurate, review of participants' job titles showed that modeled estimates were often unexpectedly high given the low-exposure tasks found in these jobs. Differences between the high-exposure jobs used to create the statistical models (obtained from air measurements in the published literature) and the low-exposure jobs in the actual study population is a potential explanation for the disagreement between the two methods. Investigators should be aware that statistical models estimating exposure intensity using existing data from one type of worker population might not be generalizable to all populations of workers.
[Mh] Termos MeSH primário: Compostos Clorados/análise
Exposição Ocupacional/análise
Solventes/análise
[Mh] Termos MeSH secundário: Monitoramento Ambiental/métodos
Seres Humanos
Saúde do Trabalhador
Estudos Retrospectivos
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE; RESEARCH SUPPORT, U.S. GOV'T, P.H.S.
[Nm] Nome de substância:
0 (Chlorine Compounds); 0 (Solvents)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:171120
[Lr] Data última revisão:
171120
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170408
[St] Status:MEDLINE
[do] DOI:10.1080/15459624.2016.1269177


  7 / 1327 MEDLINE  
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[PMID]:28367867
[Au] Autor:Takahashi K; Tanaka R; Fukuzaki S
[Ad] Endereço:Industrial Technology Center of Okayama Prefecture.
[Ti] Título:Kinetics of the Inactivation of Vibrio parahaemolyticus in Weakly Acidic Sodium Chlorite Solution.
[So] Source:Biocontrol Sci;22(1):25-30, 2017.
[Is] ISSN:1884-0205
[Cp] País de publicação:Japan
[La] Idioma:eng
[Ab] Resumo: The kinetics of the inactivation of Vibrio parahaemolyticus in sodium chlorite (NaClO ) solution was studied in the weakly acidic pH range of 4.0 to 6.5 and at various temperatures. The logarithmic reduction of the survival ratio depended on the concentration-time product, and all the inactivation curves showed a linear reduction phase. The first-order inactivation rate constant (k) increased by approximately twice for every 0.44 unit fall in pH. During the inactivation experiments, no formation of chlorine dioxide occurred. These data indicated that undissociated HClO was the active species governing the inactivation of V. parahaemolyticus. It was also shown that the use of weakly acidic NaClO solutions containing high concentrations of ionized ClO gave slower kinetics of the inactivation, whereas it could achieve the significant reduction of viable cells of more than 4-log. The k value showed an Arrhenius-type temperature dependence in the temperature range of 5 to 40℃. The apparent activation energy for the inactivation of V. parahaemolyticus was estimated to be 43.5 kJ/mol. The k value increased by approximately 1.8 times for every 10℃ rise in temperature.
[Mh] Termos MeSH primário: Cloretos/química
Cloretos/farmacologia
Concentração de Íons de Hidrogênio
Viabilidade Microbiana/efeitos dos fármacos
Vibrio parahaemolyticus/efeitos dos fármacos
[Mh] Termos MeSH secundário: Compostos Clorados/farmacologia
Desinfetantes/química
Desinfetantes/farmacologia
Cinética
Óxidos/farmacologia
Soluções
Temperatura Ambiente
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Chlorides); 0 (Chlorine Compounds); 0 (Disinfectants); 0 (Oxides); 0 (Solutions); 8061YMS4RM (chlorine dioxide); Z63H374SB6 (chlorite)
[Em] Mês de entrada:1704
[Cu] Atualização por classe:170418
[Lr] Data última revisão:
170418
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170404
[St] Status:MEDLINE
[do] DOI:10.4265/bio.22.25


  8 / 1327 MEDLINE  
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[PMID]:28327506
[Au] Autor:Ma JW; Huang BS; Hsu CW; Peng CW; Cheng ML; Kao JY; Way TD; Yin HC; Wang SS
[Ad] Endereço:Unique Biotech Co., Ltd., Rm. 1, 22 F, No. 56, Minsheng 1st Road, Xinxing District, Kaohsiung 800, Taiwan. a26154295@gmail.com.
[Ti] Título:Efficacy and Safety Evaluation of a Chlorine Dioxide Solution.
[So] Source:Int J Environ Res Public Health;14(3), 2017 Mar 22.
[Is] ISSN:1660-4601
[Cp] País de publicação:Switzerland
[La] Idioma:eng
[Ab] Resumo:In this study, a chlorine dioxide solution (UC-1) composed of chlorine dioxide was produced using an electrolytic method and subsequently purified using a membrane. UC-1 was determined to contain 2000 ppm of gaseous chlorine dioxide in water. The efficacy and safety of UC-1 were evaluated. The antimicrobial activity was more than 98.2% reduction when UC-1 concentrations were 5 and 20 ppm for bacteria and fungi, respectively. The half maximal inhibitory concentrations (IC ) of H1N1, influenza virus B/TW/71718/04, and EV71 were 84.65 ± 0.64, 95.91 ± 11.61, and 46.39 ± 1.97 ppm, respectively. A 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) test revealed that the cell viability of mouse lung fibroblast L929 cells was 93.7% at a 200 ppm UC-1 concentration that is over that anticipated in routine use. Moreover, 50 ppm UC-1 showed no significant symptoms in a rabbit ocular irritation test. In an inhalation toxicity test, treatment with 20 ppm UC-1 for 24 h showed no abnormality and no mortality in clinical symptoms and normal functioning of the lung and other organs. A ClO2 concentration of up to 40 ppm in drinking water did not show any toxicity in a subchronic oral toxicity test. Herein, UC-1 showed favorable disinfection activity and a higher safety profile tendency than in previous reports.
[Mh] Termos MeSH primário: Compostos Clorados/farmacologia
Compostos Clorados/toxicidade
Desinfetantes de Equipamento Odontológico/farmacologia
Desinfetantes de Equipamento Odontológico/toxicidade
Óxidos/farmacologia
Óxidos/toxicidade
Segurança
[Mh] Termos MeSH secundário: Animais
Bactérias/efeitos dos fármacos
Linhagem Celular
Compostos Clorados/administração & dosagem
Segurança de Produtos ao Consumidor
Desinfetantes de Equipamento Odontológico/administração & dosagem
Olho/efeitos dos fármacos
Feminino
Fungos/efeitos dos fármacos
Pulmão/efeitos dos fármacos
Masculino
Camundongos
Modelos Animais
Óxidos/administração & dosagem
Coelhos
Testes de Toxicidade
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Chlorine Compounds); 0 (Dental Disinfectants); 0 (Oxides); 8061YMS4RM (chlorine dioxide)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171016
[Lr] Data última revisão:
171016
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170323
[St] Status:MEDLINE


  9 / 1327 MEDLINE  
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[PMID]:28319884
[Au] Autor:Ali SN; Ansari FA; Arif H; Mahmood R
[Ad] Endereço:Department of Biochemistry, Faculty of Life Sciences, Aligarh Muslim University, Aligarh 202002, U.P., India.
[Ti] Título:Sodium chlorate induces DNA damage and DNA-protein cross-linking in rat intestine: A dose dependent study.
[So] Source:Chemosphere;177:311-316, 2017 Jun.
[Is] ISSN:1879-1298
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Sodium chlorate (NaClO ) is widely used in paper and pulp industries and as a non-selective herbicide. It is also a major by-product generated upon disinfection of drinking water by chlorine dioxide. In this study, we have investigated the genotoxicity of NaClO on the small intestine of rats. Adult male rats were divided into 5 groups: one control and four NaClO treated groups. The NaClO treated groups were given a single acute oral dose of NaClO (100, 250, 500 and 750 mg/kg body weight) and sacrificed 24 h later. Administration of NaClO caused significant DNA damage in a dose dependent manner in the rat intestine. This was evident from the comet assay which showed DNA strand breaks and was further confirmed by agarose gel electrophoresis and release of free nucleotides. Increased DNA protein cross-linking in NaClO administered groups showed formation of a critical lesion which hampers activities of proteins/enzymes involved in DNA repair, transcription and replication. Thus, oral administration of NaClO induces DNA damage in the rat intestine, probably through chlorate induced production of reactive oxygen species.
[Mh] Termos MeSH primário: Cloratos/toxicidade
Dano ao DNA
Reparo do DNA
[Mh] Termos MeSH secundário: Administração Oral
Animais
Peso Corporal
Cloratos/administração & dosagem
Compostos Clorados
Ensaio Cometa
Reagentes para Ligações Cruzadas/química
DNA/química
Desinfecção
Relação Dose-Resposta a Droga
Água Potável
Herbicidas
Intestino Delgado/efeitos dos fármacos
Masculino
Óxidos
Ratos
Espécies Reativas de Oxigênio/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Chlorates); 0 (Chlorine Compounds); 0 (Cross-Linking Reagents); 0 (Drinking Water); 0 (Herbicides); 0 (Oxides); 0 (Reactive Oxygen Species); 8061YMS4RM (chlorine dioxide); 9007-49-2 (DNA); T95DR77GMR (sodium chlorate)
[Em] Mês de entrada:1705
[Cu] Atualização por classe:170531
[Lr] Data última revisão:
170531
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170321
[St] Status:MEDLINE


  10 / 1327 MEDLINE  
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[PMID]:28301286
[Au] Autor:Ofori I; Maddila S; Lin J; Jonnalagadda SB
[Ad] Endereço:a School of Chemistry & Physics, University of KwaZulu-Natal , Westville Campus, Chiltern Hills, Durban , South Africa.
[Ti] Título:Chlorine dioxide oxidation of Escherichia coli in water - A study of the disinfection kinetics and mechanism.
[So] Source:J Environ Sci Health A Tox Hazard Subst Environ Eng;52(7):598-606, 2017 Jun 07.
[Is] ISSN:1532-4117
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:This study investigated the kinetics and mechanism of chlorine dioxide (ClO ) inactivation of a Gram-negative bacteria Escherichia coli (ATCC 35218) in oxidant demand free (ODF) water in detail as a function of disinfectant concentration (0.5-5.0 mg/L), water pH (6.5-8.5), temperature variations (4-37°C) and bacterial density (10 -10 cfu/mL). The effects of ClO on bacterial cell morphology, outer membrane permeability, cytoplasmic membrane disruption and intracellular enzymatic activity were also studied to elucidate the mechanism of action on the cells. Increasing temperature and disinfectant concentration were proportional to the rate of cell killing, but efficacy was found to be significantly subdued at 0.5 mg/L and less dependent on the bacterial density. The bactericidal efficiency was higher at alkaline pH of 8 or above as compared to neutral and slightly acidic pH of 7 and 6.5 respectively. The disinfection kinetic curves followed a biphasic pattern of rapid inactivation within the initial 2 min which were followed by a tailing even in the presence of residual biocide. The curves were adequately described by the C Hom model. Transmission Electron Microscopy images of the bacteria cells exposed to lethal concentrations of ClO indicated very little observable morphological damage to the outer membranes of the cells. ClO however was found to increase the permeability of the outer and cytoplasmic membranes leading to the leakage of membrane components such as 260 nm absorbing materials and inhibiting the activity of the intracellular enzyme ß-D-galactosidase. It is suggested that the disruption of the cytoplasmic membrane and subsequent efflux of intracellular components result in the inactivation of the Gram-negative bacteria.
[Mh] Termos MeSH primário: Compostos Clorados/farmacologia
Desinfetantes/farmacologia
Desinfecção/métodos
Escherichia coli/efeitos dos fármacos
Modelos Teóricos
Óxidos/farmacologia
Purificação da Água/métodos
[Mh] Termos MeSH secundário: Escherichia coli/ultraestrutura
Concentração de Íons de Hidrogênio
Cinética
Microscopia Eletrônica de Transmissão
Oxirredução
Temperatura Ambiente
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Chlorine Compounds); 0 (Disinfectants); 0 (Oxides); 8061YMS4RM (chlorine dioxide)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170925
[Lr] Data última revisão:
170925
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170317
[St] Status:MEDLINE
[do] DOI:10.1080/10934529.2017.1293993



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