The Evaluation of Genotoxicity Using DNA Repairing Test for Chemicals Produced in Chlorination and Ozonation Processes

1991 ◽  
Vol 23 (1-3) ◽  
pp. 329-338 ◽  
Author(s):  
Yoshiro Ono ◽  
Isao Somiya ◽  
Masasumi Kawamura
Keyword(s):  
Dna Repair ◽  
Organic Compounds ◽  
Quantitative Evaluation ◽  
Trichloroacetic Acid ◽  
Research Work ◽  
Dichloroacetic Acid ◽  
Umu Test ◽  
Organic Halogenated Compounds ◽  
By Products ◽  
Microsomal Activation

The umu-test which can detect the induction of DNA repair is applied in order to analyze the genotoxicity of by-products of chlorination and ozonation. In this research work, the genotoxicities of 37 comnercial chemicals which are expected to be involved in the by-products of chlorination and ozonation processes are checked and evaluated by the umu-test. The genotoxicities of the following organic halogenated compounds are clearly detected: Without microsomal activation; m-dichlorobenzene, 1,2,4-trichlorobenzene and bromoform: With microsomal activation; m-dichlorobenzene, dichloroacetic acid, trichloroacetic acid and chloral are detected. From the results on some compounds which are expected to be produced by ozonation, formaldehyde and ionone show positive genotoxicities without microsomal activation, and 5 compounds have positive genotoxicities with microsomal activation; formaldehyde, furfrol, carvone, glyoxal and acrolein. The effects of the concentration on genotoxicities of those chemicals are discussed and compared with the results obtained in other bacterial assays. Some of the selected organic compounds, chloroform and so on, are identified positive genotoxic, which were reported not to be mutagenic in other bacterial assays. As the Quantitative evaluation for genotoxicity on chemical dose, the time of DNA repairing on damaged spots by SOS genes and the induction rate of umu gene are experimentally evaluated.

scholarly journals Exposure to disinfectant by-products and the risk of stillbirth in Massachusetts

2018 ◽  
Vol 75 (10) ◽  
pp. 742-751 ◽  
Author(s):  
Zorimar Rivera-Núñez ◽  
J Michael Wright ◽  
Amy Meyer
Keyword(s):  
Drinking Water ◽  
Trichloroacetic Acid ◽  
Dichloroacetic Acid ◽  
Haloacetic Acids ◽  
Future Research ◽  
Second Trimester ◽  
Exposure Response ◽  
Exposure Metrics ◽  
Monobromoacetic Acid ◽  
By Products

ObjectivesWe examined stillbirths in relation to disinfection by-product (DBP) exposures including chloroform, bromodichloromethane (BDCM), dibromochloromethane, bromoform, trichloroacetic acid, dichloroacetic acid (DCAA), monobromoacetic acid and summary DBP measures (trihalomethanes (THM4), haloacetic acids (HAA5), THMBr (brominated trihalomethanes) and DBP9 (sum of THM4 and HAA5)).MethodsWe randomly selected 10 controls for each of the 2460 stillbirth cases with complete quarterly 1997–2004 THM4 and HAA5 town-level drinking water data. Adjusted (aORs) were calculated based on weight-averaged second-trimester DBP exposures.ResultsWe detected statistically significant associations for stillbirths and the upper DCAA quartiles (aOR range: 1.50–1.71). We also found positive associations for the upper four HAA5 quintiles and different stillbirth cause of death categories that were examined including unexplained stillbirth (aOR range: 1.24–1.72), compression of umbilical cord (aOR range: 1.08–1.94), prematurity (aOR range: 1.37–2.88), placental separation and haemorrhage (aOR range: 1.44–2.01) and asphyxia/hypoxia (aOR range: 1.52–1.97). Additionally, we found positive associations between stillbirths and chloroform exposure (aOR range: 1.29 – 1.36) and unexplained stillbirths and BDCM exposure (aOR range: 1.51 – 1.78). We saw no evidence of exposure–response relationships for any categorical DBP metrics.ConclusionsConsistent with some previous studies, we found associations between stillbirths and chloroform and unexplained stillbirth and BDCM exposures. These findings strengthen existing evidence of prenatal THM exposures increasing the risk of stillbirth. Additionally, we saw statistically significant associations between DCAA and stillbirth. Future research should examine cause-specific stillbirths in relation to narrower critical windows and additional DBP exposure metrics beyond trihalomethanes and haloacetic acids.

scholarly journals Modeling of RO/NF membrane rejections of PhACs and organic compounds: a statistical analysis

2008 ◽  
Vol 1 (1) ◽  
pp. 7-15 ◽  
Author(s):  
V. Yangali-Quintanilla ◽  
T.-U. Kim ◽  
M. Kennedy ◽  
G. Amy
Keyword(s):  
Dipole Moment ◽  
Molar Volume ◽  
Organic Compounds ◽  
Equivalent Width ◽  
Trichloroacetic Acid ◽  
Statistical Significance ◽  
Principal Component ◽  
Dichloroacetic Acid ◽  
Neutral Compounds ◽  
Molecular Length

Abstract. Rejections of pharmaceutical compounds (Ibuprofen, Diclofenac, Clofibric acid, Naproxen, Primidone, Phenacetin) and organic compounds (Dichloroacetic acid, Trichloroacetic acid, Chloroform, Bromoform, Trichloroethene, Perchloroethene, Carbontetrachloride, Carbontetrabromide) by NF (Filmtec, Saehan) and RO (Filmtec, Saehan, Toray, Koch) membranes were studied. Chloroform presented the lowest rejection due to small molar volume, equivalent width and length. Diclofenac and Primidone showed high rejections related to high molar volume and length. Dichloroacetic acid and Trichloroacetic acid presented good rejections caused by charge exclusion instead of steric hindrance mechanism influencing rejection. Bromoform and Trichloroethene showed low rejections due to small length and equivalent width. Carbontetrabromide, Perchloroethene and Carbontetrachloride with higher equivalent width than BF and TCE presented better rejections. A qualitative analysis of variables using Principal Component Analysis was successfully implemented for reduction of physical-chemical compound properties that influence membrane rejection of PhACs and organic compounds. Properties such as dipole moment, molar volume, hydrophobicity/hydrophilicity, molecular length and equivalent width were found to be important descriptors for simulation of membrane rejection. For membranes used in the experiments, we may conclude that charge repulsion was an important mechanism of rejection for ionic compounds. After analysis with Multiple Linear Regression, we also may conclude that membrane rejection of neutral compounds was well predicted by molar volume, length, equivalent width, hydrophobicity/hydrophilicity and dipole moment. Molecular weight was a poor descriptor variable for rejection modelling. We were able to provide acceptable statistical significance for important results.

Formation of HAAs during Chlorination of Aspartic Acid in Drinking Water

2011 ◽  
Vol 250-253 ◽  
pp. 3425-3428 ◽  
Author(s):  
Zhong Lin Chen ◽  
An Li ◽  
Sheng Jun Wang ◽  
Ying Han ◽  
Feng Liu ◽  
...  
Keyword(s):  
Amino Acids ◽  
Reaction Time ◽  
Aspartic Acid ◽  
Trichloroacetic Acid ◽  
Initial Period ◽  
Dichloroacetic Acid ◽  
Haloacetic Acids ◽  
Chlorination Process ◽  
Alkaline Conditions ◽  
By Products

As a traditional disinfection method, chlorination disinfection is used generally in the plants ,however, disinfection by-products (DBPs) during chlorination process generate accordingly. Nitrogenous organic compounds is a kind of important precursors of DBPs. Haloacetic acids (HAAs) is one kind of the main DBPs. Aspartic acid (Asp) is one kind of elementary amino acids,which are typical nitrogenous organic compounds.In this paper, the formation characteristics of HAAs by Asp under different chlorination disinfection conditions have been researched, such as reaction time, chlorine dosage, pH, temperature and Br- . The results show that the yields of dichloroacetic acid(DCAA) and trichloroacetic acid(TCAA) are both increased with the reaction time increasing,and the formation rates is accelerated at the initial period; With the increase of chlorine dosage, the yields of DCAA and TCAA increased; The yield of DCAA and TCAA are both low in the acidic condition and high in the conditions of neutral and alkaline conditions. The yield of DCAA and TCAA increased with the increase of temperature. When there is Br- in water, bromided-HAAs can be formed.The total HAAs yield and BIF both increase with the increase of Br- concentration. The HAAs constituents contain DCAA,TCAA,BCAA,DBCAA, DCBAA, DBAA and TBAA. At low Br- concentration,the order of HAAs constituents yields is DCAA>BCAA>DCBAA>TCAA>DBCAA> DBAA>TBAA.

scholarly journals Prediction of RO/NF membrane rejections of PhACs and organic compounds: a statistical analysis

2008 ◽  
Vol 1 (1) ◽  
pp. 21-44 ◽  
Author(s):  
V. Yangali-Quintanilla ◽  
T.-U. Kim ◽  
M. Kennedy ◽  
G. Amy
Keyword(s):  
Dipole Moment ◽  
Molar Volume ◽  
Organic Compounds ◽  
Equivalent Width ◽  
Trichloroacetic Acid ◽  
Principal Component ◽  
Dichloroacetic Acid ◽  
Neutral Compounds ◽  
Molecular Length ◽  
Ionic Compounds

Abstract. Rejections of pharmaceutical compounds (Ibuprofen, Diclofenac, Clofibric acid, Naproxen, Primidone, Phenacetin) and organic compounds (Dichloroacetic acid, Trichloroacetic acid, Chloroform, Bromoform, Trichloroethene, Perchloroethene, Carbontetrachloride, Carbontetrabromide) by NF (Filmtec, Saehan) and RO (Filmtec, Saehan, Toray, Koch) membranes were studied. Chloroform presented the lowest rejection due to small molar volume, equivalent width and length. Diclofenac and Primidone showed high rejections related to high molar volume and length. Dichloroacetic acid and Trichloroacetic acid presented good rejections caused by charge exclusion instead of steric hindrance mechanism influencing rejection. Bromoform and Trichloroethene showed low rejections due to small length and equivalent width. Carbontetrabromide, Perchloroethene and Carbontetrachloride with higher equivalent width than BF and TCE presented better rejections. A qualitative analysis of variables using Principal Component Analysis was successfully implemented for reduction of physical-chemical compound properties that influence membrane rejection of PhACs and organic compounds. Properties such as dipole moment, molar volume, hydrophobicity/hydrophilicity, molecular length and equivalent width were found to be important descriptors for prediction of membrane rejection. Ionic and neutral compounds were successfully separated before analysis. For membranes used in the experiments, we may conclude that charge repulsion was an important mechanism of rejection for ionic compounds. Molecular weight was a poor variable for rejection prediction. Membrane rejection of neutral compounds was well predicted by dipole moment, molar volume, length, equivalent width and hydrophobicity/hydrophilicity of compounds after analysis with Multiple Linear Regression.

Sintesis dan Karakterisasi Na-CMC dari A-Selulosa Serabut Kelapa Sawit

2021 ◽  
Vol 1 (9) ◽  
pp. 375-381
Author(s):  
Indriani Indriani ◽  
Abu Hasan ◽  
Anerasari Meydinariasty
Keyword(s):  
Palm Oil ◽  
Trichloroacetic Acid ◽  
Reaction Medium ◽  
Synthesis Process ◽  
Optimal Composition ◽  
Palm Fiber ◽  
Oil Processing ◽  
Reaction Media ◽  
By Products

Na-CMC adalah eter polimer selulosa linier yang digunakan sebagai bahan pengental, pengemulsi dan penstabil. Salah satu bahan dasar pembuatan Na-CMC yaitu serabut kelapa sawit. Serabut kelapa sawit merupakan salah satu hasil samping terbesar yang dihasilkan dalam proses pengolahan minyak kelapa sawit dan dapat dapat dijadikan sebagai sumber selulosa karena mengandung selulosa hingga 59,60%. Tujuan dari penelitian ini untuk mendaptakan komposisi optimal campuran media reaksi isopropanol-etanol dan konsentrasi asam trikloroasetat serta konsentrasi NaOH dengan memvariasikan komposisi media reaksi isopropanol-etanol menjadi 20:80; 40:60; 50:50; 60:40 dan 80:20, sedangkan untuk konsentrasi asam trikloroasetat yaitu 15%, 20% san 25% dan untuk konsentrasi NaOH adlah 15% dan 20%. Didapat bahwa  komposisi optimal media reaksi pada proses sintesis Na-CMC terdapat pada campuran isopropanol-etanol 80:20 dengan konsentrasi asam trikloroasetat 25% dan konsentrasi NaOH 20% menghasilkan nilai DS yang tertinggi yaitu sebesar 0,8124 dengan kemurnian dan pH berturut-turut sebesar 99,68% dan 7,9.   Na-CMC is a linear cellulose polymer ether used as a thickener, emulsifier and stabilizer. One of the basic ingredients for making Na-CMC is palm fiber. Palm fiber is one of the largest by-products produced in the palm oil processing process and can be used as a source of cellulose because it contains up to 59.60% cellulose. The purpose of this study was to obtain the optimal composition of the isopropanol-ethanol reaction media mixture and the concentration of trichloroacetic acid and NaOH concentration by varying the composition of the isopropanol-ethanol reaction medium to 20:80; 40:60; 50:50; 60:40 and 80:20, while the concentrations of trichloroacetic acid were 15%, 20% and 25% and the concentrations of NaOH were 15% and 20%, respectively. It was found that the optimal composition of the reaction medium in the Na-CMC synthesis process was found in a mixture of isopropanol-ethanol 80:20 with a concentration of 25% trichloroacetic acid and 20% NaOH concentration resulting in the highest DS value of 0.8124 with purity and pH respectively. 99.68% and 7.9.

Self-radiation induced exchange between tritiated water and organic compounds. The labelling of L-chiro-inositol, myo-inositol and Hexa-O-methyl-L-chiro-inositol

1975 ◽  
Vol 28 (9) ◽  
pp. 1981 ◽  
Author(s):  
DHT Fong ◽  
CL Bodkin ◽  
MA Long ◽  
JL Garnett
Keyword(s):  
Organic Compounds ◽  
Radiochemical Purity ◽  
Specific Activity ◽  
Tritiated Water ◽  
High Specific Activity ◽  
Methyl Derivative ◽  
Radiation Induced ◽  
By Products ◽  
Gas Exposure

The stereochemistry of the tritiation of L-chiro-inositol, myo-inositol and hexa-O-methyl-L-chiro-inositol by self-radiation induced exchange with tritiated water of high specific activity has been investigated. Predominance of configurational retention was found to accompany tritium labelling in the two inositols, while substantial configurational inversion occurred in the hexa-O-methyl derivative. Tritiation occurred predominantly at C 1 in L-chiro-inositol, with slight inversion at this position alone accompanying the labelling. Comparison with Wilzbach T2 gas exposure results indicates the HTO method yields less by-products, myo-inositol having a radiochemical purity of 97%.

Formation characteristics of carbonaceous and nitrogenous disinfection by-products depending on residual organic compounds by CGS and DAF

2018 ◽  
Vol 26 (33) ◽  
pp. 34008-34017 ◽  
Author(s):  
Minsoo Maeng ◽  
Nirmal Kumar Shahi ◽  
Gwyam Shin ◽  
Heejong Son ◽  
Dongheui Kwak ◽  
...  
Keyword(s):  
Organic Compounds ◽  
By Products

scholarly journals Electro-Absorbers: A Comparison on Their Performance with Jet-Absorbers and Absorption Columns

Catalysts ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 653
Author(s):  
Monserrat Castañeda-Juárez ◽  
Martín Muñoz-Morales ◽  
Fernanda Lourdes Souza ◽  
Cristina Sáez ◽  
Pablo Cañizares ◽  
...  
Keyword(s):  
Carbon Tetrachloride ◽  
Trichloroacetic Acid ◽  
Packed Column ◽  
Scale Up ◽  
Applied Current ◽  
Absorption Column ◽  
Applied Current Density ◽  
Current Densities ◽  
Surface Jet ◽  
By Products

This work focuses on the removal of perchloroethylene (PCE) from gaseous streams using absorbers connected with electrolyzers. Two types of absorption devices (jet absorber and absorption column) were compared. In addition, it has been evaluated the different by-products generated when a simultaneous electrolysis with diamond anodes is carried out. PCE was not mineralized, but it was transformed into phosgene that mainly derivates into carbon tetrachloride. Trichloroacetic acid was also formed, but in much lower amounts. Results showed a more efficient absorption of PCE in the packed column, which it is associated to the higher gas–liquid contact surface. Jet absorber seems to favor the production of carbon tetrachloride in gaseous phase, whereas the packed column promotes a higher concentration of trichloroacetic acid in liquid. It was also evaluated the scale up of the electrolytic stage of these electro-absorption devices by using a stack with five perforated electrode packages instead of a single cell. Clarification of the effect of the applied current density on the speciation attained after the electrolysis of the absorbent has been attempted. Experiments reveal similar results in terms of PCE removal and a reduced generation of gaseous intermediates at lower current densities.

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