Characterization of indicator bacteria in municipal raw water, drinking water, and new main water samples

1982 ◽  
Vol 28 (9) ◽  
pp. 1002-1013 ◽  
Author(s):  
J. A. Clark ◽  
C. A. Burger ◽  
L. E. Sabatinos
Keyword(s):  
Drinking Water ◽  
Water Samples ◽  
Membrane Filter ◽  
Bacterial Species ◽  
Gas Production ◽  
Indicator Bacteria ◽  
Water Type ◽  
Raw Water ◽  
Water Drinking ◽  
Pollution Indicator

Municipal water samples were analyzed by membrane filter (MF) and presence–absence (P-A) tests for pollution indicator bacteria. In four years, 11 514 bacterial cultures were isolated from either raw water, drinking water, or new main water samples submitted to three environmental laboratories. The bacterial species occurring most often in all types of water samples were Escherichia coli (11.6–39.7%), Enterobacter aerogenes (18.1–26.3%), Aeromonas hydrophila (8.8–17.0%), Klebsiella pneumoniae (7.7–10.3%), and Citrobacter freundii (5.09–22.7%). A lactose – lauryl tryptose – tryptone broth was examined as an alternative medium to modified MacConkey broth in the presumptive portion of the P-A test. The intensity of acid and gas production in presumptive positive P-A bottles was compared with the types and frequencies of indicator bacteria shown by confirmatory tests. The results of detecting indicator bacteria following the analysis of 53 130 samples over a 2-year period were arranged by water source (well, lake, river, mixed) and water type (raw or drinking) to determine the influence of these parameters on the recovery of indicator bacteria. A further subdivision of the sample types into raw surface, raw ground, in-plant, plant discharge, reservoir, and distribution samples demonstrated the effect of water treatment practices.

A presence–absence (P–A) test providing sensitive and inexpensive detection of coliforms, fecal coliforms, and fecal streptococci in municipal drinking water supplies

1968 ◽  
Vol 14 (1) ◽  
pp. 13-18 ◽  
Author(s):  
J. A. Clark
Keyword(s):  
Drinking Water ◽  
Water Samples ◽  
Membrane Filter ◽  
Gas Production ◽  
Fecal Coliforms ◽  
Coliform Bacteria ◽  
Isolation Medium ◽  
Negative Results ◽  
Fecal Streptococci ◽  
Confirmatory Tests

A simple presence–absence (P–A) test was developed to provide a more economical and more sensitive method for conducting coliform analyses on municipal drinking water samples than the membrane filter (MF) technique. Over ninety percent of these samples routinely gave negative results by the MF method. A modified MacConkey broth, enriched to improve on acid and gas production by coliforms, was the isolation medium for the presumptive part of the P–A test.Parallel analyses of water samples were made by both the P–A and MF methods. Confirmatory tests established the reliability of the respective procedures to detect coliform bacteria. A statistical analysis of the results showed that the P–A test was more sensitive for detecting lower levels of pollution than the MF technique. Many of the confirmed positive P–A results came from P–A bottles that produced presumptive positive tests only after an extended incubation period of two to five days.The P–A test was about five times less expensive than the MF technique and by adding a few simple tests, the P–A procedure could give information on the presence of both fecal coliforms and fecal streptococci. For several samples, fecal streptococci were found by P–A tests in the absence of detectable coliform bacteria by either the MF or P–A methods of analysis.

Pollution indicator bacteria associated with municipal raw and drinking water supplies

1977 ◽  
Vol 23 (4) ◽  
pp. 465-470 ◽  
Author(s):  
James A. Clark ◽  
Jane E. Pagel
Keyword(s):  
Drinking Water ◽  
Membrane Filter ◽  
Most Probable Number ◽  
Raw Water ◽  
False Negatives ◽  
Probable Number ◽  
Frequency Distributions ◽  
Bacterial Cultures ◽  
Or Groups ◽  
Pollution Indicator

A total of 3819 bacterial cultures isolated from municipal water samples were identified using a combination of Enterotubes and confirmatory media. Frequency distributions for the different genera or groups of bacteria were similar for raw water and drinking water isolations, except for Escherichia organisms which doubled their frequency in raw water. Differences between the membrane filter (MF) and presence–absence (P–A) test with regard to types of organisms isolated were limited to Klebsiella organisms which were preferentially cultured from MF plates. Members of the genus Enterobacter were isolated more than twice as frequently as any of the other coliform genera dealt with in this study. Aeromonas organisms were detected almost as often as such individual genera as Escherichia, Citrobacter, or Klebsiella.Although non-lactose fermenting colonies (false-negatives) of the coliform genera would not be detected by the MF technique, their lack of detection would likely be offset by the Aeromonas colonies (false-positives). At least 25% of the coliform isolates were either anaerogenic or non-lactose fermenters and would therefore go undetected by the most probable number (MPN) technique.

Occurrence of 1,4-dioxane and MTBE in drinking water sources in Japan

2006 ◽  
Vol 6 (2) ◽  
pp. 47-53 ◽  
Author(s):  
D. Simazaki ◽  
M. Asami ◽  
T. Nishimura ◽  
S. Kunikane ◽  
T. Aizawa ◽  
...  
Keyword(s):  
Drinking Water ◽  
Surface Water ◽  
Water Samples ◽  
Quality Standards ◽  
Raw Water ◽  
Water Quality Standards ◽  
Butyl Ether ◽  
Water Treatment Plants ◽  
Standard Value ◽  
Surface Water Samples

Nationwide surveys of 1,4-dioxane and methyl-t-butyl ether (MTBE) levels in raw water used for the drinking water supply were conducted at 91 water treatment plants in Japan in 2001 and 2002, prior to the revision of the drinking water quality standards. 1,4-dioxane was widely and continuously detected in raw water samples and its occurrence was more frequent and its concentrations higher in groundwater than in surface water. However, its maximum concentration in raw water was much lower than its new standard value (50 μg/L), which was determined as a level of 10−5 excessive cancer risk to humans. Trace levels of MTBE were also detected in several surface water samples.

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 Arsenic from community water fluoridation: quantifying the effect

2015 ◽  
Vol 14 (2) ◽  
pp. 236-242
Author(s):  
Emily Peterson ◽  
Howard Shapiro ◽  
Ye Li ◽  
John G. Minnery ◽  
Ray Copes
Keyword(s):  
Drinking Water ◽  
Arsenic Concentration ◽  
Drinking Water Treatment ◽  
National Standards ◽  
Water Type ◽  
Raw Water ◽  
Water Fluoridation ◽  
Community Water ◽  
The Difference ◽  
Community Water Fluoridation

Community water fluoridation is a WHO recommended strategy to prevent dental carries. One debated concern is that hydrofluorosilicic acid, used to fluoridate water, contains arsenic and poses a health risk. This study was undertaken to determine if fluoridation contributes to arsenic in drinking water, to estimate the amount of additional arsenic associated with fluoridation, and compare this to the National Sanitation Foundation/American National Standards Institute (NSF/ANSI) standard and estimates from other researchers. Using surveillance data from Ontario drinking water systems, mixed effects linear regression was performed to examine the effect of fluoridation status on the difference in arsenic concentration between raw water and treated water samples. On average, drinking water treatment was found to reduce arsenic levels in water in both fluoridated and non-fluoridated systems by 0.2 μg/L. However, fluoridated systems were associated with an additional 0.078 μg/L (95% CI 0.021, 0.136) of arsenic in water when compared to non-fluoridated systems (P = 0.008) while controlling for raw water arsenic concentrations, types of treatment processes, and source water type. Our estimate is consistent with concentrations expected from other research and is less than 10% of the NSF/ANSI standard of 1 μg/L arsenic in water. This study provides further information to inform decision-making regarding community water fluoridation.

Treatment of taste and odor causing substances in drinking water

1997 ◽  
Vol 35 (8) ◽  
pp. 29-36 ◽  
Author(s):  
Youngsug Kim ◽  
Yeongho Lee ◽  
Chai S. Gee ◽  
Euiso Choi
Keyword(s):  
Water Quality ◽  
Drinking Water ◽  
Iodine Number ◽  
Water Samples ◽  
Pilot Plant ◽  
Raw Water ◽  
Process Scheme ◽  
Taste And Odor ◽  
Detectable Concentration ◽  
Removal Efficiencies

To collect fundamental data for the improvement of drinking water quality, focusing on the removal of 2-MIB, Geosmin, IPMP, IBMP and TCA, a total of 20m3/d pilot plant was operated with process schemes of GAC with post-O3(PP-I), and without ozonation(PP-II). Five taste and odor causing substances could be removed to non-detectable concentration with PP-I, but GAC alone was not so effective as PP-I. The larger the EBCT and Iodine Number of GAC column employed, the higher the removal efficiencies expected. The minimum EBCT and Iodine Number were respectively 15 min and 1,000 mg/g of GAC column. Geosmin removal efficiencies ranged 30 to 40% at 15.6 ng/l during conventional process scheme, but 70 to 80% removal was achieved by the PP-I and 60 to 70% by PP-II was achieved. IPMP removal efficiencies were 60 to 80% with GAC only. IBMP and TCA were seldom detected in raw water samples, but TCA was the most difficult to remove of five taste and odor causing substances.

scholarly journals Development of a Rapid Method for Simultaneous Recovery of Diverse Microbes in Drinking Water by Ultrafiltration with Sodium Polyphosphate and Surfactants

2005 ◽  
Vol 71 (11) ◽  
pp. 6878-6884 ◽  
Author(s):  
Vincent R. Hill ◽  
Amy L. Polaczyk ◽  
Donghyun Hahn ◽  
Jothikumar Narayanan ◽  
Theresa L. Cromeans ◽  
...  
Keyword(s):  
Drinking Water ◽  
Water Samples ◽  
Tap Water ◽  
Bacterial Species ◽  
Surfactant Solution ◽  
Tween 80 ◽  
Sample Collection ◽  
Sodium Polyphosphate ◽  
Concentration Method ◽  
Serovar Typhimurium

ABSTRACT The ability to simultaneously concentrate diverse microbes is an important consideration for sample collection methods that are used for emergency response and environmental monitoring when drinking water may be contaminated with an array of unknown microbes. This study focused on developing a concentration method using ultrafilters and different combinations of a chemical dispersant (sodium polyphosphate [NaPP]) and surfactants. Tap water samples were seeded with bacteriophage MS2, Escherichia coli, Enterococcus faecalis, Cryptosporidium parvum, 4.5-μm microspheres, Salmonella enterica serovar Typhimurium, Bacillus globigii endospores, and echovirus 1. Ten-liter tap water samples were concentrated to ∼250 ml in 12 to 42 min, depending on the experimental condition. Initial experiments indicated that pretreating filters with fetal bovine serum or NaPP resulted in an increase in microbe recovery. The addition of NaPP to the tap water samples resulted in significantly higher microbe and microsphere recovery efficiencies. Backflushing of the ultrafilter was found to significantly improve recovery efficiencies. The effectiveness of backflushing was improved further with the addition of Tween 80 to the backflush solution. The ultrafiltration method developed in this study, incorporating the use of NaPP pretreatment and surfactant solution backflushing, was found to recover MS2, C. parvum, microspheres, and several bacterial species with mean recovery efficiencies of 70 to 93%. The mean recovery efficiency for echovirus 1 (49%) was the lowest of the microbes studied for this method. This research demonstrates that ultrafiltration can be effective for recovering diverse microbes simultaneously in tap water and that chemical dispersants and surfactants can be beneficial for improving microbial recovery using this technique.

Bromide Ion Removal by Coagulation in Drinking Water

2013 ◽  
Vol 448-453 ◽  
pp. 1188-1191
Author(s):  
Qi Zhu ◽  
Dong Mei Liu ◽  
Fu Yi Cui ◽  
Lei Fang
Keyword(s):  
Drinking Water ◽  
Water Samples ◽  
Removal Rate ◽  
Raw Water ◽  
Songhua River ◽  
Ion Removal ◽  
Bromide Ions ◽  
Bromide Ion ◽  
The Songhua River ◽  
Better Than

In order to prove the rules of bromide ion remove in coagulation treatment stage in drinking water, by carrying out laboratory coagulation test in simulated water and the Songhua River raw water samples, the effects of bromine ion removal by coagulation of PAC, FeCl3 and the compound ferrous were investigated. The results showed that when the dosage of PAC was 60mg/L, the average removal rate of bromine ion was 50.6% by coagulation in the simulated water samples, and the rate was 44.8% in raw water samples of the Songhua River. In the conditions of FeCl3 dosage 70mg/L, the average removal rate of bromine ion was 56.1% in the simulated water sample, and the rate was 55.2% in raw water. When Reduce the same turbidity of drinking water, the effect of bromide ions removal by FeCl3 coagulation was better than that of PAC. When the dosage of compound ferrous (Ferrosilicon ratio of 1:1) as coagulant was 16.8mg/L, the bromide ions removal rate up to 67.6%.

scholarly journals Concentrations of Halosuccinic Acids in Raw Water, Drinking Water and Boiled Driking Water

2007 ◽  
Vol 17 (4) ◽  
pp. 643-648
Author(s):  
Yasuo TAKAHASHI ◽  
Sukeo ONODERA ◽  
Masatoshi MORITA
Keyword(s):  
Drinking Water ◽  
Raw Water ◽  
Water Drinking

scholarly journals A Breakthrough in Water Purification Using an Oligodynamic Metal and Moringa Oleifera Seed

2018 ◽  
Author(s):  
Alakaparampil Joseph Varkey
Keyword(s):  
Drinking Water ◽  
Water Purification ◽  
Water Samples ◽  
Moringa Oleifera ◽  
Technical Assistance ◽  
Cost Effective ◽  
Power Source ◽  
Raw Water ◽  
Treated Water ◽  
Moringa Oleifera Seed

A simple, efficient and stand-alone method for purification of river water using moringa seed powder and copper is discussed. Coagulant property of the seed powder clears turbid raw water and the oligodynamic activity of copper completely destroys E.coli bacteria. Both raw and treated water samples were tested for contaminants to verify the efficacy of the system. Treated water has turbidity in the range 3 NTU - 5 NTU and non-detected (< 1 MPN/100 mL) E.coli count making it suitable for drinking. The technique is very cost effective and can be practiced anywhere using locally available materials. It does not require a power source or any technical assistance. Being a stand-alone system the technique exceptionally useful in providing drinking water as an immediate solution in disaster areas affected by cyclone or floods.

Sign in / Sign up

Export Citation Format

Share Document