Identification, toxicity and control of iodinated disinfection byproducts in cooking with simulated chlor(am)inated tap water and iodized table salt

2016 ◽  
Vol 88 ◽  
pp. 60-68 ◽  
Author(s):  
Yang Pan ◽  
Xiangru Zhang ◽  
Yu Li
Keyword(s):  
Tap Water ◽  
Disinfection Byproducts ◽  
Table Salt ◽  
And Control

THE UPTAKE OF TRITIATED LYSINE VASOPRESSIN BY RAT AND PIG PITUITARY NEURAL LOBES IN VITRO

1971 ◽  
Vol 50 (4) ◽  
pp. 669-677 ◽  
Author(s):  
B. A. EDWARDS
Keyword(s):  
Tap Water ◽  
Exchange Chromatography ◽  
Control Group ◽  
Breakdown Product ◽  
Nacl Solution ◽  
Water Control ◽  
Neural Lobe ◽  
Lysine Vasopressin ◽  
And Control

SUMMARY Uptake of tritiated lysine vasopressin ([3H]LVP) was studied in halved neural lobes of rats (which had been given either tap water (control group) or 2% (w/v) NaCl solution as drinking water for 4 days) as well as in slices of pig neural lobe. Uptake of radioactivity into the neural lobes was shown but analysis of the extracts of incubated lobes of both species by ion exchange chromatography showed that very little of it remained in the tissue as hormone. In addition, some radioactivity was associated with trichloroacetic acid-insoluble proteins. After 90 min of incubation, and after correction for the breakdown, the uptake of unchanged [3H]LVP, expressed as a tissue: medium ratio, was 0·14 ± 0·04 and 0·09 ± 0·03 (mean ± s.e.m.) for the saline-treated and control rats respectively, while the tissue: medium ratios for the breakdown product(s) were 6·47 ± 0·45 and 5·50 ± 0·36. The results suggest uptake of [3H]LVP into the cell with almost complete intracellular breakdown of the hormone.

An experimental study for chlorine residual and trihalomethane formation with rechlorination

2007 ◽  
Vol 55 (1-2) ◽  
pp. 307-313 ◽  
Author(s):  
J. Lee ◽  
D. Lee ◽  
J. Sohn
Keyword(s):  
Distribution System ◽  
Distribution Systems ◽  
Water Distribution ◽  
Disinfection Byproducts ◽  
Correction Coefficient ◽  
Empirical Power ◽  
Chlorine Residual ◽  
Chlorine Decay ◽  
And Control ◽  
Large Distribution

Maintenance of adequate chlorine residuals and control of disinfection byproducts (DBPs) throughout water distribution systems is currently an important issue. In particular, rechlorination can be a powerful tool in controlling adequate chlorine residual in a large distribution system. The patterns of chlorine decay and formation of DBPs due to rechlorination are different from those of chlorination; chlorine decay is slower and trihalomethane (THM) formation is lower with rechlorination. The present study evaluates whether existing predictive models for chlorine residual and THM formation are applicable in the case of rechlorination. A parallel first-order decay model represents the best simulation results for chlorine decay, and an empirical power function model (modified Amy model) with an introduced correction coefficient (ϕ1, ϕ2) is more suitable to THM formation.

Degradation of pesticides by chlorination during water purification

1994 ◽  
Vol 30 (7) ◽  
pp. 119-128 ◽  
Author(s):  
Yasumoto Magara ◽  
Takako Aizawa ◽  
Naohisa Matumoto ◽  
Fumikazu Souna
Keyword(s):  
Water Supply ◽  
Tap Water ◽  
Water Quality Management ◽  
Raw Water ◽  
Natural Conditions ◽  
Chlorobenzoic Acid ◽  
Pesticides In Water ◽  
And Control ◽  
Purification Plant ◽  
By Products

An attempt was made to detect pesticides remaining in river water and raw water for tap water supply, located in an agricultural area. As a result, 11 kinds of pesticides were detected. The residual pesticides in water were also degraded to by-products, since chlorine is a strong oxidant that does not exist in natural conditions. Organophosphate pesticides containing P = S bonds were easily degraded and produced oxons (P = O) as a primary by-product. Thiobencarb was also degraded by chlorination, producing chlorobenzyl alcohol, chlorotoluene, chlorobenzyl chloride, chlorobenzoic acid and chlorobenzyl aldehyde as chlorination by-products. Also, when thiobencarb was detected in raw water, the above by-products were detected in the filtered water in a purification plant for water supply. Therefore, the management and control of pesticides in drinking water and ambient water quality management should include testing for chlorination by-products.

scholarly journals Cytogenotoxicity of Abattoir Effluent in Clarias gariepinus (Burchell, 1822) Using Micronucleus Test

2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Chibuisi G. Alimba ◽  
Ebenezer O. Ajayi ◽  
Titilayo Hassan ◽  
Akindayo A. Sowunmi ◽  
Adekunle A. Bakare
Keyword(s):  
Micronucleus Test ◽  
Tap Water ◽  
Clarias Gariepinus ◽  
Oxygen Demand ◽  
Negative Control ◽  
Control Fish ◽  
Dependent Manner ◽  
Nuclear Abnormality ◽  
And Control ◽  
Positive Controls

The cytogenotoxic potential of abattoir effluent from Bodija, Nigeria, was investigated using micronucleus test in Clarias gariepinus. Fish was exposed to five different concentrations: 0.2, 0.4, 0.8, 1.6, and 3.1% of the effluent for 7, 14, and 28 days. Tap water and 0.02 mL/L of benzene were used as negative and positive controls, respectively. Physicochemical parameters and heavy metals were analyzed in the effluent in accordance with standard methods. After exposure, blood was collected from the treated and control fish and slides were prepared for micronuclei (MN) and nuclear abnormality evaluation in the peripheral erythrocytes. The effluent induced significant (p<0.05) increase in the frequency of MN in a time dependent manner. Similarly, the frequency of total nuclear abnormalities (blebbing, notch, bud, binucleation, and vacuolation) was higher in the exposed fish than the negative control. Electrical conductivity, nitrate, biochemical oxygen demand, chemical oxygen demand, arsenic, and copper analyzed in the effluent may have provoked the observed cytogenetic damage. The findings herein suggest the presence of clastogens and cytotoxins in Bodija abattoir wastewater which are capable of increasing genomic instability in aquatic biota.

scholarly journals Network Model Analysis of Residual Chlorine to Reduce Disinfection Byproducts in Water Supply Systems in Yangon City, Myanmar

Water ◽  
2021 ◽  
Vol 13 (20) ◽  
pp. 2921
Author(s):  
Nwe Nwe Zin ◽  
Shinobu Kazama ◽  
Satoshi Takizawa
Keyword(s):  
Water Quality ◽  
Water Supply ◽  
Tap Water ◽  
Water Quality Monitoring ◽  
Disinfection Byproducts ◽  
Residual Chlorine ◽  
Water Supply Systems ◽  
Formation Kinetics ◽  
Chlorine Decay ◽  
Supply Systems

In Yangon City, chlorination commenced in January 2020 to supply drinkable water; therefore, there is as yet no information on chlorine decay and DBP formation in the water supply system. This study aimed to find methods to optimize chlorine dosage in Yangon City. Onsite sampling and laboratory analyses of residual chlorine and trihalomethane (THM) formation, as well as water quality simulations, were conducted to find the chlorine decay and THM formation kinetics. Due to a high chlorine dose of 2 mg/L for both pre- and post-chlorination, disinfection was effective despite the low removal efficiency of turbidity. However, THMs were found in high levels in both treated and tap water due to the high THM formation potential of raw water. The re-contamination and/or transformation of dissolved organic matter were found in the distribution network by increases in specific ultraviolet absorption (SUVA) values and excitation-emission matrix (EEM) fluorophores, which brought about variations of THMs in the networks. The EPANET models were run assuming there to be no water leakages; it was found that the chlorine dose could be decreased to 0.8 mg/L to meet the guidelines for THMs and residual chlorine. The methods employed in this study could be also applied in other water supply systems in tropical developing countries with limited water quality monitoring data.

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