scholarly journals Determination of free chlorine based on ion chromatography—application of glycine as a selective scavenger

2020 ◽  
Vol 412 (28) ◽  
pp. 7713-7722 ◽  
Author(s):  
Mohammad Sajjad Abdighahroudi ◽  
Torsten C. Schmidt ◽  
Holger V. Lutze
Keyword(s):  
Drinking Water ◽  
Ion Chromatography ◽  
Distribution System ◽  
Method Performance ◽  
Water Matrix ◽  
Routine Monitoring ◽  
Repeatability And Reproducibility ◽  
Secondary Oxidant ◽  
Comparison Of The Results ◽  
Water Measurement

Abstract Free available chlorine (FAC) is the most widely used chemical for disinfection and in secondary disinfection; a minimum chlorine residual must be present in the distribution system. FAC can also be formed as an impurity in ClO2 production as well as a secondary oxidant in the ClO2 application, which has to be monitored. In this study, a new method is developed based on the reaction of FAC with glycine in which the amine group selectively scavenges FAC and the N-chloroglycine formed can be measured by ion chromatography with conductivity detector (IC-CD). Utilizing IC for N-chloroglycine measurement allows this method to be incorporated into routine monitoring of drinking water anions. For improving the sensitivity, IC was coupled with post-column reaction and UV detection (IC-PCR-UV), which was based on iodide oxidation by N-chloroglycine resulting in triiodide. The method performance was quantified by comparison of the results with the N,N-diethyl-p-phenylenediamine (DPD) method due to the unavailability of an N-chloroglycine standard. The N-chloroglycine method showed limits of quantification (LOQ) of 24 μg L−1 Cl2 and 13 μg L−1 Cl2 for IC-CD and IC-PCR-UV, respectively. These values were lower than those of DPD achieved in this research and in ultrapure water. Measurement of FAC in the drinking water matrix showed comparable robustness and sensitivity with statistically equivalent concentration that translated to recoveries of 102% for IC-CD and 105% for IC-PCR-UV. Repeatability and reproducibility performance were enhanced in the order of DPD, IC-CD, and IC-PCR-UV. Measurement of intrinsic FAC in the ClO2 application revealed that the N-chloroglycine method performed considerably better in such a system where different oxidant species (ClO2, FAC, chlorite, etc.) were present.

Determination of Dissolved Bromate in Drinking Water by Ion Chromatography and Post Column Reaction: Interlaboratory Study

2011 ◽  
Vol 94 (5) ◽  
pp. 1592-1600 ◽  
Author(s):  
Fernando Cordeiro ◽  
Piotr Robouch ◽  
Maria Beatriz de la Calle ◽  
Håkan Emteborg ◽  
Jean Charoud-Got ◽  
...  
Keyword(s):  
Drinking Water ◽  
Ion Chromatography ◽  
Standard Method ◽  
Collaborative Study ◽  
Swimming Pool ◽  
Performance Characteristics ◽  
Method Performance ◽  
Pool Water ◽  
Swimming Pool Water

Abstract A collaborative study, International Evaluation Measurement Programme®-25a, was conducted in accordance with international protocols to determine the performance characteristics of an analytical method for the determination of dissolved bromate in drinking water. The method should fulfill the analytical requirements of Council Directive 98/83/EC (referred to in this work as the Drinking Water Directive; DWD). The new draft standard method under investigation is based on ion chromatography followed by post-column reaction and UV detection. The collaborating laboratories used the Draft International Organization for Standardization (ISO)/Draft International Standard (DIS) 11206 document. The existing standard method (ISO 15061:2001) is based on ion chromatography using suppressed conductivity detection, in which a preconcentration step may be required for the determination of bromate concentrations as low as 3 to 5 μg/L. The new method includes a dilution step that reduces the matrix effects, thus allowing the determination of bromate concentrations down to 0.5 μg/L. Furthermore, the method aims to minimize any potential interference of chlorite ions. The collaborative study investigated different types of drinking water, such as soft, hard, and mineral water. Other types of water, such as raw water (untreated), swimming pool water, a blank (named river water), and a bromate standard solution, were included as test samples. All test matrixes except the swimming pool water were spiked with high-purity potassium bromate to obtain bromate concentrations ranging from 1.67 to 10.0 μg/L. Swimming pool water was not spiked, as this water was incurred with bromate. Test samples were dispatched to 17 laboratories from nine different countries. Sixteen participants reported results. The repeatability RSD (RSDr) ranged from 1.2 to 4.1%, while the reproducibility RSD (RSDR) ranged from 2.3 to 5.9%. These precision characteristics compare favorably with those of ISO 15601. A thorough comparison of the performance characteristics is presented in this report. All method performance characteristics obtained in the frame of this collaborative study indicate that the draft ISO/DIS 11206 standard method meets the requirements set down by the DWD. It can, therefore, be considered to fit its intended analytical purpose.

DISINFEKSI UNTUK PROSES PENGOLAHAN AIR MINUM

2018 ◽  
Vol 3 (1) ◽  
Author(s):  
Nusa Idaman Said
Keyword(s):  
Drinking Water ◽  
Water Purification ◽  
Distribution System ◽  
Residual Effect ◽  
Drinking Water Treatment ◽  
Disinfection Byproducts ◽  
Water Disinfection ◽  
Pathogenic Microorganisms ◽  
Microbiological Contamination ◽  
Disinfection Process

Water disinfection means the removal, deactivation or killing of pathogenic microorganisms. Microorganisms are destroyed or deactivated, resulting in termination of growth and reproduction. When microorganisms are not removed from drinking water, drinking water usage will cause people to fall ill. Chemical inactivation of microbiological contamination in natural or untreated water is usually one of the final steps to reduce pathogenic microorganisms in drinking water. Combinations of water purification steps (oxidation, coagulation, settling, disinfection, and filtration) cause (drinking) water to be safe after production. As an extra measure many countries apply a second disinfection step at the end of the water purification process, in order to protect the water from microbiological contamination in the water distribution system. Usually one uses a different kind of disinfectant from the one earlier in the process, during this disinfection process. The secondary disinfection makes sure that bacteria will not multiply in the water during distribution. This paper describes several technique of disinfection process for drinking water treatment. Disinfection can be attained by means of physical or chemical disinfectants. The agents also remove organic contaminants from water, which serve as nutrients or shelters for microorganisms. Disinfectants should not only kill microorganisms. Disinfectants must also have a residual effect, which means that they remain active in the water after disinfection. For chemical disinfection of water the following disinfectants can be used such as Chlorine (Cl2),  Hypo chlorite (OCl-), Chloramines, Chlorine dioxide (ClO2), Ozone (O3), Hydrogen peroxide etch. For physical disinfection of water the following disinfectants can be used is Ultraviolet light (UV). Every technique has its specific advantages and and disadvantages its own application area sucs as environmentally friendly, disinfection byproducts, effectivity, investment, operational costs etc. Kata Kunci : Disinfeksi, bakteria, virus, air minum, khlor, hip khlorit, khloramine, khlor dioksida, ozon, UV.

The effect of distribution system biofilm bacteria on copper concentrations in drinking water

2002 ◽  
Vol 2 (1) ◽  
pp. 319-324
Author(s):  
M.M. Critchley ◽  
N.J. Cromar ◽  
N. McClure ◽  
H.J. Fallowfield
Keyword(s):  
Public Health ◽  
Drinking Water ◽  
Distribution System ◽  
Xanthomonas Maltophilia ◽  
Biofilm Bacteria ◽  
Rhodococcus Sp

This study investigated the potential for distribution system biofilm bacteria to elevate copper concentrations in drinking water. Biofilms were sampled from household copper reticulation pipes and grown on R2A agar. Laboratory coupon experiments were used to determine the effect of single isolate biofilms on aqueous copper concentrations. The majority of biofilm bacteria did not affect copper concentrations in comparison to sterile controls. However, several bacteria including Acidovorax delafieldii, Cytophaga johnsonae and Micrococcus kristinae were shown to significantly elevate copper concentrations in drinking water. In contrast, the bacteria Rhodococcus sp. and Xanthomonas maltophilia were shown to significantly decrease copper levels in comparison to controls. The significance of biofilm bacteria to increase copper concentrations in drinking water has implications for public health by increasing concentrations to levels toxic to humans.

Assessment of Lisbon drinking water distribution network biofilm colonization and associated hazards

2008 ◽  
Vol 8 (4) ◽  
pp. 421-426
Author(s):  
J. Menaia ◽  
M. Benoliel ◽  
A. Lopes ◽  
C. Neto ◽  
E. Ferreira ◽  
...  
Keyword(s):  
Drinking Water ◽  
Distribution System ◽  
Water Distribution ◽  
Water Distribution System ◽  
Water Distribution Network ◽  
Storage Tanks ◽  
Water Pipe ◽  
Cultural Methods ◽  
Drinking Water Distribution ◽  
And Storage

Concerns arise from the possible occurrence of pathogens in drinking water pipe biofilms and storage tank sediments. In these studies, biofilm samples from pipes and sediments from storage tanks of the Lisbon drinking water distribution system were analyzed. Protein determinations and heterotrophic counts on pipe biofilm samples were used to assess the Lisbon network sessile colonization intensity and distribution. Indicator and pathogenic microorganisms were analyzed in pipe biofilm samples, as well as in storage tanks biofilm and sediments, by using cultural methods and PCR, to assess risks. Results have shown that the Lisbon network sessile colonization is relatively weak in intensity. In addition, no meaningful hazards were apparent for both the network biofilm and the storage tanks biofilm and sediments.

Persistence and decontamination of surrogate radioisotopes in a model drinking water distribution system

2009 ◽  
Vol 43 (20) ◽  
pp. 5005-5014 ◽  
Author(s):  
Jeffrey G. Szabo ◽  
Christopher A. Impellitteri ◽  
Shekar Govindaswamy ◽  
John S. Hall
Keyword(s):  
Drinking Water ◽  
Distribution System ◽  
Water Distribution ◽  
Water Distribution System ◽  
Drinking Water Distribution System ◽  
Drinking Water Distribution

VULNERABILITY ASSESSMENT OF A DRINKING WATER DISTRIBUTION SYSTEM

2007 ◽  
Vol 2007 (1) ◽  
pp. 449-467
Author(s):  
Stacia L. Thompson ◽  
Elizabeth Casman ◽  
Paul Fischbeck ◽  
Mitchell J. Small ◽  
Jeanne M. VanBriesen
Keyword(s):  
Drinking Water ◽  
Vulnerability Assessment ◽  
Distribution System ◽  
Water Distribution ◽  
Water Distribution System ◽  
Drinking Water Distribution System ◽  
Drinking Water Distribution

scholarly journals Biofilm forming ability of Sphingomonas paucimobilis isolated from community drinking water systems on plumbing materials used in water distribution

2017 ◽  
Vol 15 (6) ◽  
pp. 942-954 ◽  
Author(s):  
Parul Gulati ◽  
Moushumi Ghosh
Keyword(s):  
Drinking Water ◽  
Distribution System ◽  
Biofilm Formation ◽  
Water Distribution ◽  
Sem Analysis ◽  
Sphingomonas Paucimobilis ◽  
Simulated Distribution ◽  
Flow Through ◽  
Materials Used ◽  
Biofilm Development

Sphingomonas paucimobilis, an oligotroph, is well recognized for its potential for biofilm formation. The present study explored the biofilm forming ability of a strain isolated from municipal drinking water on plumbing materials. The intensity of biofilm formation of this strain on different plumbing materials was examined by using 1 × 1 cm2 pieces of six different pipe materials, i.e. polyvinyl chloride (PVC), polypropylene (PP), polyethylene (PE), aluminium (Al), copper (Cu) and rubber (R) and observing by staining with the chemical chromophore, Calcofluor. To understand whether biofilm formation occurs under flow through conditions, a laboratory-scale simulated distribution system, comprised of the above materials was fabricated. Biofilm samples were collected from the designed system at different biofilm ages (10, 40 and 90 hours old) and enumerated. The results indicated that the biofilm formation occurred on all plumbing materials with Cu and R as exceptions. The intensity of biofilm formation was found to be maximum on PVC followed by PP and PE. We also demonstrated the chemical chromophore (Calcofluor) successfully for rapid and easy visual detection of biofilms, validated by scanning electron microscope (SEM) analysis of the plumbing materials. Chlorination has little effect in preventing biofilm development.

scholarly journals A systematic review of waterborne disease burden methodologies from developed countries

2014 ◽  
Vol 12 (4) ◽  
pp. 634-655 ◽  
Author(s):  
H. M. Murphy ◽  
K. D. M. Pintar ◽  
E. A. McBean ◽  
M. K. Thomas
Keyword(s):  
Systematic Review ◽  
Drinking Water ◽  
Health Risks ◽  
Distribution System ◽  
National Level ◽  
Developed Countries ◽  
Extreme Weather Events ◽  
Treatment Level ◽  
Waterborne Disease ◽  
True Incidence

The true incidence of endemic acute gastrointestinal illness (AGI) attributable to drinking water in Canada is unknown. Using a systematic review framework, the literature was evaluated to identify methods used to attribute AGI to drinking water. Several strategies have been suggested or applied to quantify AGI attributable to drinking water at a national level. These vary from simple point estimates, to quantitative microbial risk assessment, to Monte Carlo simulations, which rely on assumptions and epidemiological data from the literature. Using two methods proposed by researchers in the USA, this paper compares the current approaches and key assumptions. Knowledge gaps are identified to inform future waterborne disease attribution estimates. To improve future estimates, there is a need for robust epidemiological studies that quantify the health risks associated with small, private water systems, groundwater systems and the influence of distribution system intrusions on risk. Quantification of the occurrence of enteric pathogens in water supplies, particularly for groundwater, is needed. In addition, there are unanswered questions regarding the susceptibility of vulnerable sub-populations to these pathogens and the influence of extreme weather events (precipitation) on AGI-related health risks. National centralized data to quantify the proportions of the population served by different water sources, by treatment level, source water quality, and the condition of the distribution system infrastructure, are needed.

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