scholarly journals Formation of chlorinated organics in drinking water of Instanbul (Turkey) and Salerno (Italy)

2013 ◽  
Vol 7 (1) ◽  
pp. 95-105
Keyword(s):  
Drinking Water ◽  
Developed Countries ◽  
The Other ◽  
Raw Water ◽  
Surface Water Resources ◽  
Water Origin ◽  
Treatment Technologies ◽  
By Products ◽  
Different Levels

The occurrence of THMs and HAAs, and other volatile organics in Istanbul (Turkey) and Salerno (Italy) surface water resources was investigated by the previous and present data obtained on raw, coagulated, pre-chlorinated, pre-ozonated water samples. The present drinking water directives/regulations in developed countries set maximum contaminant level (MCL) for THMs at different levels. In Italy, where the 80-85% of water demand is supplied by groundwater, a relatively low THMs value of 30 μg l-1 was set, however there are no HAAs and bromate limits. On the other hand, there is still no regulation for the THMs in Turkey. The characterization of chlorinated by-products, particularly THMs, is detailed according to raw water origin and treatment technologies currently applied in both cities.

Temporal variability of disinfection by-products concentration in urban public water system

2013 ◽  
Vol 14 (4) ◽  
pp. 393-398
Keyword(s):  
Drinking Water ◽  
Water Samples ◽  
Temporal Variability ◽  
Water System ◽  
The Other ◽  
Major Constituent ◽  
System P ◽  
Public Water System ◽  
Drinking Water Samples ◽  
By Products

The occurrence of trihalomethanes (THMs) was studied in the drinking water samples from urban water supply network of Karachi city that served more than 18 million people. Drinking water samples were collected from 58 locations in summer (May-August) and winter (November-February) seasons. The major constituent of THMs detected was chloroform in winter (92.34%) and summer (93.07%), while the other THMs determined at lower concentrations. Summer and winter concentrations of total THMs at places exceed the levels regulated by UEPA (80 μg l-1) and WHO (100 μg l-1). GIS linked temporal variability in two seasons showed significantly higher median concentration (2.5%-23.06%) of THMs compared to winter.

Enteric viruses in drinking water supplies

2002 ◽  
Vol 2 (3) ◽  
pp. 17-22
Author(s):  
A.P. Wyn-Jones ◽  
J. Watkins ◽  
C. Francis ◽  
M. Laverick ◽  
J. Sellwood
Keyword(s):  
Drinking Water ◽  
Heavy Rainfall ◽  
Liquid Culture ◽  
Plaque Assay ◽  
Enteric Viruses ◽  
Enteric Virus ◽  
The Other ◽  
Raw Water ◽  
Rt Pcr ◽  
Water Supplies

Two rural spring drinking water supplies were studied for their enteric virus levels. In one, serving about 30 dwellings, the water was chlorinated before distribution; in the other, which served a dairy and six dwellings the water was not treated. Samples of treated (40 l) and untreated (20 l) water were taken under normal and heavy rainfall conditions over a six weeks period and concentrated by adsorption/elution and organic flocculation. Infectious enterovirus in concentrates was detected in liquid culture and enumerated by plaque assay, both in BGM cells, and concentrates were also analysed by RT-PCR. Viruses were found in both raw water supplies. Rural supplies need to be analysed for viruses as well as bacterial and protozoan pathogens if the full microbial hazard is to be determined.

Characterization of organic matter and disinfection by-products in membrane backwash water from drinking water treatment

2009 ◽  
Vol 168 (2-3) ◽  
pp. 753-759 ◽  
Author(s):  
Lingling Zhang ◽  
Ping Gu ◽  
Zijie Zhong ◽  
Dong Yang ◽  
Wenjie He ◽  
...  
Keyword(s):  
Drinking Water ◽  
Organic Matter ◽  
Water Treatment ◽  
Drinking Water Treatment ◽  
By Products

Contribution of brominated organic disinfection by-products to the mutagenicity of drinking water

2004 ◽  
Vol 50 (5) ◽  
pp. 321-328 ◽  
Author(s):  
S. Echigo ◽  
S. Itoh ◽  
T. Natsui ◽  
T. Araki ◽  
R. Ando
Keyword(s):  
Drinking Water ◽  
Health Risk ◽  
Chromosomal Aberrations ◽  
The Other ◽  
Major Contributor ◽  
Sequential Process ◽  
Analytical Technique ◽  
Organic Chlorine ◽  
Chromosomal Aberration Test ◽  
By Products

The activity inducing chromosomal aberrations of the mixture of brominated disinfection by-products (DBPs) was approximately three times higher than that of the chlorinated counterparts for the same hypohalous acid dose. With the combination of chromosomal aberration test and a new analytical technique to differentiate total organic chlorine (TOCl) and total organic bromine (TOBr), it was found that TOBr was correlated to the mutagenicity of chlorinated waters. It was also implied that for a bromide-to-TOC ratio of 0.1 (mg/mg C), brominated DBPs could account for at least 29% of the total toxicity of DBPs formed during chlorination. On the other hand, bromate ion, a major ozonation DBP, was not a major contributor to the activity inducing chromosomal aberrations of the water treated with an ozone/chlorine sequential process. Therefore, ozonation is one possible option to reduce the health risk caused by DBPs even in the presence of bromide.

Characterization of Drinking Water Odour Arising from Spring Thaw for an Ice-Covered Upland River Source

1992 ◽  
Vol 25 (2) ◽  
pp. 65-72 ◽  
Author(s):  
S. E. Hrudey ◽  
D. Rector ◽  
N. Motkosky
Keyword(s):  
Drinking Water ◽  
Activated Carbon ◽  
Water Samples ◽  
Raw Water ◽  
Mass Spectral ◽  
The North ◽  
Water Conditions ◽  
Biogenic Source ◽  
Chromatographic Mass

Recurring odour events during spring thaw in the North Saskatchewan River led to a program to characterize contributing odour agents. Raw and treated water samples were adsorbed on granular activated carbon which was then exhaustively solvent extracted. The solvent concentrates were subjected to a Chromatographie sniffing procedure combined with gas chromatographic-mass spectral analyses. Geosmin and 2-methylisoborneol were identified by sensory and analytical means as likely major contributors to the raw water odour. Benzaldehyde, camphor and dihydroactinidiolide were other relevant compounds identified. Given the near freezing water conditions at the time of the odour event, the biogenic source of the odour agents remains a subject for investigation.

scholarly journals The Effect of Different Boiling and Filtering Devices on the Concentration of Disinfection By-Products in Tap Water

2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Glòria Carrasco-Turigas ◽  
Cristina M. Villanueva ◽  
Fernando Goñi ◽  
Panu Rantakokko ◽  
Mark J. Nieuwenhuijsen
Keyword(s):  
Drinking Water ◽  
Health Effects ◽  
Reverse Osmosis ◽  
Tap Water ◽  
Epidemiological Studies ◽  
The Other ◽  
Large Decrease ◽  
Adverse Health Effects ◽  
Before And After ◽  
By Products

Disinfection by-products (DBPs) are ubiquitous contaminants in tap drinking water with the potential to produce adverse health effects. Filtering and boiling tap water can lead to changes in the DBP concentrations and modify the exposure through ingestion. Changes in the concentration of 4 individual trihalomethanes (THM4) (chloroform (TCM), bromodichloromethane (BDCM), dibromochloromethane (DBCM), and bromoform (TBM)), MX, and bromate were tested when boiling and filtering high bromine-containing tap water from Barcelona. For filtering, we used a pitcher-type filter and a household reverse osmosis filter; for boiling, an electric kettle, a saucepan, and a microwave were used. Samples were taken before and after each treatment to determine the change in the DBP concentration. pH, conductivity, and free/total chlorine were also measured. A large decrease of THM4 (from 48% to 97%) and MX concentrations was observed for all experiments. Bromine-containing trihalomethanes were mostly eliminated when filtering while chloroform when boiling. There was a large decrease in the concentration of bromate with reverse osmosis, but there was a little effect in the other experiments. These findings suggest that the exposure to THM4 and MX through ingestion is reduced when using these household appliances, while the decrease of bromate is device dependent. This needs to be considered in the exposure assessment of the epidemiological studies.

Integrated Disinfection By-Products Mixtures Research: Comprehensive Characterization of Water Concentrates Prepared from Chlorinated and Ozonated/Postchlorinated Drinking Water

2008 ◽  
Vol 71 (17) ◽  
pp. 1165-1186 ◽  
Author(s):  
Susan D. Richardson ◽  
Alfred D. Thruston ◽  
Stuart W. Krasner ◽  
Howard S. Weinberg ◽  
Richard J. Miltner ◽  
...  
Keyword(s):  
Drinking Water ◽  
By Products ◽  
Comprehensive Characterization

scholarly journals Identification and characterization of 19 predicted Myb-family DNA binding proteins in Magnaporthe oryzae concerning growth, conidiation, and pathogenicity

2021 ◽  
Author(s):  
Ya Li ◽  
Xiuxia Zheng ◽  
Mengtian Pei ◽  
Mengting Chen ◽  
Shengnan Zhang ◽  
...  
Keyword(s):  
Stress Response ◽  
Dna Binding ◽  
Magnaporthe Oryzae ◽  
Expression Profiles ◽  
Dna Binding Proteins ◽  
The Other ◽  
Genes Encoding ◽  
Identification And Characterization ◽  
Different Levels

Genes encoding for proteins containing the DNA binding Myb domain have been suggested to be important in regulating development and stress response in eukaryotes, including fungi. Magnaporthe oryzae (teleomorph Pyricularia oryzae) is considered the most destructive pathogen of rice. We screen the M. oryzae genome for all genes encoding proteins containing Myb domains since these genes could be essential during pathogenesis. We found 19 genes Myb1-19. Only a few have previously been investigated, and only one has proven to be involved in pathogenesis. We tried to delete the other 18 genes and succeeded with all except 6, five of which could be essential. RT-qPCR showed that all 19 genes are expressed during pathogenesis, although at different levels and with different expression profiles. To our surprise, only deletions of the genes encoding proteins MoMyb2, MoMyb13, and MoMyb15 showed growth, conidiation, and infection phenotypes, indicating that they are essential on their own during infection. This lack of phenotypes for the other mutants surprised us, and we extended the analysis to look for expression co-regulation and found 5 co-regulated groups of predicted proteins with Myb-domains. We point to likely compensatory regulations of the other Myb-family genes hiding the effect of many deletions. Further studies of the Myb-family genes are thus of interest since revealing the functions of these genes with a possible effect on pathogenicity since these could be targets for future measures to control M. oryzae in rice.

scholarly journals Removal of oxidative stress and genotoxic activities during drinking water production by ozonation and granular activated carbon filtration

2021 ◽  
Vol 33 (1) ◽  
Author(s):  
Maria Yu ◽  
Elin Lavonen ◽  
Agneta Oskarsson ◽  
Johan Lundqvist
Keyword(s):  
Oxidative Stress ◽  
Drinking Water ◽  
Activated Carbon ◽  
Drinking Water Treatment ◽  
Pilot Scale ◽  
Full Scale ◽  
Raw Water ◽  
Treatment Efficiency ◽  
Drinking Water Production ◽  
Treatment Technologies

Abstract Background Bioanalytical tools have been shown to be useful in drinking water quality assessments. Here, we applied a panel of in vitro bioassays to assess the treatment efficiency of two pilot-scale treatments: ozonation and granular activated carbon (GAC) filtration at a drinking water treatment plant (DWTP). The pilot-scale systems were studied alongside a full-scale treatment process consisting of biological activated carbon (BAC) filtration, UV disinfection, and monochloramine dosing. Both systems were fed the same raw water treated with coagulation/flocculation/sedimentation and sand filtration. The endpoints studied were oxidative stress (Nrf2 activity), genotoxicity (micronuclei formations), aryl hydrocarbon receptor (AhR) activation, as well as estrogen receptor (ER) and androgen receptor (AR) activity. Results Nrf2, AhR, and ER activities and genotoxic effects were detected in the incoming raw water and variability was observed between the sampling events. Compared to most of the samples taken from the full-scale treatment system, lower Nrf2, AhR, and ER bioactivities as well as genotoxicity were observed in all samples from the pilot-scale systems across all sampling events. The most pronounced treatment effect was a 12-fold reduction in Nrf2 activity and a sixfold decrease in micronuclei formations following ozonation alone. GAC filtration alone resulted in sevenfold and fivefold reductions in Nrf2 activity and genotoxicity, respectively, in the same sampling event. Higher bioactivities were detected in most samples from the full-scale system suggesting a lack of treatment effect. No androgenic nor anti-androgenic activities were observed in any sample across all sampling events. Conclusions Using effect-based methods, we have shown the presence of bioactive chemicals in the raw water used for drinking water production, including oxidative stress, AhR and ER activities as well as genotoxicity. The currently used treatment technologies were unable to fully remove the observed bioactivities. Ozonation and GAC filtration showed a high treatment efficiency and were able to consistently remove the bioactivities observed in the incoming water. This is important knowledge for the optimization of existing drinking water treatment designs and the utilization of alternative treatment technologies.

Speciation and seasonal variation of various disinfection by-products in a full-scale drinking water treatment plant in East China

2019 ◽  
Vol 19 (6) ◽  
pp. 1579-1586 ◽  
Author(s):  
Xiang-Ren Zhou ◽  
Yi-Li Lin ◽  
Tian-Yang Zhang ◽  
Bin Xu ◽  
Wen-Hai Chu ◽  
...  
Keyword(s):  
Drinking Water ◽  
Water Treatment ◽  
Treatment Plant ◽  
Drinking Water Treatment ◽  
Water Treatment Plant ◽  
Full Scale ◽  
East China ◽  
Raw Water ◽  
Drinking Water Treatment Plant ◽  
By Products

Abstract The objective of this research was to study the occurrence and seasonal variations of disinfection by-products (DBPs), including traditional carbonaceous and emerging nitrogenous DBPs, in a full-scale drinking water treatment plant (DWTP) for nearly 2 years. The removal efficiencies of each DBP through the treatment processes were also investigated. This DWTP takes raw water from the Yangtze River in East China. The quality of the raw water used in this DWTP varied with different seasons. The results suggested that DBP concentrations of the finished water were higher in spring (82.33 ± 15.12 μg/L) and summer (117.29 ± 9.94 μg/L) with higher dissolved organic carbon (DOC) levels, but lower in autumn (41.10 ± 5.82 μg/L) and winter (78.47 ± 2.74 μg/L) with lower DOC levels. Due to the increase of bromide concentration in spring and winter, more toxic brominated DBPs increased obviously and took up a greater proportion. In this DWTP, DBP concentrations increased dramatically after pre-chlorination, especially in summer. It is noteworthy that the removal of DBPs during the subsequent treatment was more obvious in spring than in the other three seasons because the pH value is more beneficial to coagulation in spring.

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