scholarly journals Bacterial Contamination of Drinking Water in Guadalajara, Mexico

2018 ◽  
Author(s):  
Francesca Rubino ◽  
Yahaira Corona ◽  
José Guadalupe Jiménez Pérez ◽  
Charlotte Smith
Keyword(s):  
Drinking Water ◽  
Microbiological Quality ◽  
Total Coliform ◽  
Coliform Bacteria ◽  
E Coli ◽  
Chlorine Residual ◽  
Piped Water ◽  
Regulatory Limits ◽  
Access To Water

In many regions where drinking water supply is intermittent and unreliable, households adapt by storing water in cisterns or rooftop tanks. Both intermittent supply and stored water can be vulnerable to contamination by microorganisms with deleterious health effects. The Guadalajara Metropolitan Area is a rapidly growing urban center with over five million residents where household storage is nearly ubiquitous. This pilot study was conducted in July 2018 to examine the microbiological quality of drinking water in Guadalajara. Samples were tested for free available chlorine residual, total coliform bacteria, and E. coli. A survey on access to water and public perspectives was also conducted. Water exiting rooftop tanks exceeded regulatory limits for total coliform levels in half of the homes studied. Piped water arriving at two homes had total coliform levels that far exceeded regulatory limits. No E. coli were detected in any of the samples. Only 35% of homes had a chlorine residual between the recommended 0.2 and 1.5 mg/L. Many homes reported unpleasant odors and colors. Only 7% of residents drank the piped water. Future studies are needed, especially during April and May when many homes reported a higher disruption to water service.

scholarly journals Bacterial Contamination of Drinking Water in Guadalajara, Mexico

2018 ◽  
Author(s):  
Francesca Rubino ◽  
Yahaira Corona ◽  
José Guadalupe Jiménez Pérez ◽  
Charlotte D. Smith
Keyword(s):  
Drinking Water ◽  
Microbiological Quality ◽  
Total Coliform ◽  
Coliform Bacteria ◽  
E Coli ◽  
Chlorine Residual ◽  
Piped Water ◽  
Regulatory Limits ◽  
Access To Water

In many regions where drinking water supply is intermittent and unreliable, households adapt by storing water in cisterns or rooftop tanks. Both intermittent supply and stored water can be vulnerable to contamination by microorganisms with deleterious health effects. The Guadalajara Metropolitan Area is a rapidly growing urban center with over five million residents where household storage is nearly ubiquitous. This pilot study was conducted in July 2018 to examine the microbiological quality of drinking water in Guadalajara. Samples were tested for free available chlorine residual, total coliform bacteria, and E. coli. A survey on access to water and public perspectives was also conducted. Water exiting rooftop tanks exceeded regulatory limits for total coliform levels in half of the homes studied. Piped water arriving at two homes had total coliform levels that far exceeded regulatory limits. No E. coli were detected in any of the samples. Only 35% of homes had a chlorine residual between the recommended 0.2 and 1.5 mg/L. Many homes reported unpleasant odors and colors. Only 7% of residents drank the piped water. Future studies are needed, especially during April and May when many homes reported a higher disruption to water service.

scholarly journals Bacterial Contamination of Drinking Water in Guadalajara, Mexico

2018 ◽  
Vol 16 (1) ◽  
pp. 67 ◽  
Author(s):  
Francesca Rubino ◽  
Yahaira Corona ◽  
José Guadalupe Jiménez Pérez ◽  
Charlotte Smith
Keyword(s):  
Drinking Water ◽  
Microbiological Quality ◽  
Total Coliform ◽  
Coliform Bacteria ◽  
E Coli ◽  
Chlorine Residual ◽  
Piped Water ◽  
Regulatory Limits ◽  
Access To Water

In many regions where drinking water supply is intermittent and unreliable, households adapt by storing water in cisterns or rooftop tanks. Both intermittent supply and stored water can be vulnerable to contamination by microorganisms with deleterious health effects. The Metropolitan Zone of Guadalajara is a rapidly growing urban center with over five million residents where household storage is nearly ubiquitous. This pilot study was conducted in July 2018 to examine the microbiological quality of drinking water in Guadalajara. Samples were tested for free available chlorine residual, total coliform bacteria, and Escherichia coli. A survey on access to water and public perspectives was also conducted. Water exiting rooftop tanks exceeded regulatory limits for total coliform levels in half of the homes studied. Piped water arriving at two homes had total coliform levels that far exceeded regulatory limits. No E. coli were detected in any of the samples. Only 35% of homes had a chlorine residual between the recommended 0.2 and 1.5 mg/L. Many homes reported unpleasant odors and colors. Only 7% of residents drank the piped water. Future studies are needed, especially during April and May when many homes reported a higher disruption to water service.

scholarly journals The health-related microbiological quality of bottled drinking water sold in Dar es Salaam, Tanzania

2006 ◽  
Vol 5 (1) ◽  
pp. 179-185 ◽  
Author(s):  
Gabriel R. Kassenga
Keyword(s):  
Drinking Water ◽  
Heterotrophic Bacteria ◽  
Tap Water ◽  
Microbiological Quality ◽  
Total Coliform ◽  
Dar Es Salaam ◽  
Bottled Water ◽  
Faecal Coliform ◽  
Coliform Bacteria

The consumption of bottled and plastic-bagged drinking water in Tanzania has increased largely because of the deteriorating quality of tap water. It is uncertain whether these water products are safe for drinking. In this study, the microbiological quality of bottled and plastic-bagged drinking water sold in Dar es Salaam, Tanzania, was investigated. One hundred and thirty samples representing 13 brands of bottled water collected from shops, supermarkets and street vendors were analysed for total coliform and faecal coliform organisms as well as heterotrophic bacteria. These were compared with 61 samples of tap water. Heterotrophic bacteria were detected in 92% of the bottled water samples analysed. Total and faecal coliform bacteria were present in 4.6% and 3.6%, respectively, of samples analysed with a tendency for higher contamination rates in plastic-bagged drinking water. Microbiological quality of tap water was found to be worse compared with bottled water, with 49.2% and 26.2% of sampling points showing the presence of total coliform and faecal coliform organisms, respectively. The results suggest caution and vigilance to avert outbreaks of waterborne diseases from these types of drinking water.

scholarly journals Sources of microbiological contamination in sachet water from Ghana

2020 ◽  
Vol 10 (2) ◽  
pp. 202-208
Author(s):  
Asli Aslan ◽  
Haresh Rochani ◽  
Oghenekpaobor Oyibo ◽  
J. Edward Dotherow ◽  
Kendall W. Anderson ◽  
...  
Keyword(s):  
Drinking Water ◽  
Quantitative Polymerase Chain Reaction ◽  
Microbiological Quality ◽  
Total Coliform ◽  
Primary Sources ◽  
Source Tracking ◽  
E Coli ◽  
Sewage Contamination ◽  
Sachet Water

Abstract Sachet water is one of the primary sources of drinking water in rapidly growing countries. A study to assess the microbiological quality of sachet water in 21 different brands was conducted in Ghana. Culturable total coliform was positive in 87% of the samples collected, where Escherichia coli colonies were absent. The analysis of quantitative polymerase chain reaction results indicated the presence of E. coli genes in 44.6% of the samples, with the highest concentration up to 3,166 CCE/100 ml. Microbial source tracking analyses showed that the source of E. coli genes did not originate from sewage contamination because the human-associated HF183 marker was not detected. Of the 175 samples tested, 71% did not mention any water treatment before filling the packages. These results suggest non-human sources of contamination, such as biofilm formation in the pipelines used to fill these packages due to poor disinfection. Our study shows an urgent need for increased regulation and standardized manufacturing of sachet water to ensure safe drinking water.

scholarly journals Point-of-Use Water Treatment Methods and the Microbiological Quality of Drinking Water in a Peri-Urban Community of Bonendale, Douala IV, Cameroon

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Ngouakam H ◽  
◽  
Fru Cho J ◽  
Tientche B ◽  
◽  
...  
Keyword(s):  
Drinking Water ◽  
Water Samples ◽  
Microbiological Quality ◽  
Coliform Bacteria ◽  
Cross Sectional ◽  
Potential Health ◽  
Coliform Count ◽  
Point Of Use ◽  
Dug Wells

Background: The study aimed at assessing the knowledge of Bonendale populations related to safe drinking water; determine the microbiological quality and the household treatment practices of drinking water at the point of use (PoU). Methods: The study was descriptive and cross-sectional, conducted between November 2017 and November 2018 in Bonendale, Douala IV. A systematic random sampling method was used to select 237 households. Results: The main source of drinking water in the study population was dug wells (64.9%). The major activity around the boreholes was agriculture 50% (6/12) while agriculture and livestock rearing were practiced around 34.3% (12/35) and 42.8% (15/35) of dug wells respectively. Nearly half 110 (46.4%) of respondents had a good knowledge of physical properties of drinking water. Fifty-nine water samples out of a total of 60 tested (98.3%) were contaminated by coliform bacteria. Analysis of water samples indicated that 47.6% (10/21) of dug wells, 37.0% (10/27) of Camwater, and 41.2% (5/12) of boreholes had a total coliform count varying between 101-1000 CFU/100mL. And only a single Camwater water sample 1 (137%) had a coliform count of 0 CFU/100mL. Conclusion: These findings indicated the poor microbiological quality of point water used by Bonendale populations representing an important potential health risk of water-borne diseases. The results also reveal that a very high proportion of households treat their PoU before drinking.

scholarly journals The rationale for introducing the indices «Generalized coliform bacteria» and «Escherichia coli» into the scheme of sanitary and microbiological control of water quality as indices of fecal contamination

2021 ◽  
Vol 99 (12) ◽  
pp. 1353-1359
Author(s):  
Angelika V. Zagainova ◽  
Galina M. Trukhina ◽  
Yury A. Rakhmanin ◽  
Tamara Z. Artemova ◽  
Marina A. Sukhina
Keyword(s):  
Escherichia Coli ◽  
Water Quality ◽  
Drinking Water ◽  
Fecal Contamination ◽  
Coliform Bacteria ◽  
E Coli ◽  
Intestinal Infections ◽  
Safety Of Drinking Water ◽  
Microbiological Indicators

Introduction. The increasing bacterial contamination of water bodies requires an increase in water quality control’s reliability to ensure epidemic safety against waterborne infections. Therefore, researchers in both Russia and Europe came to the conclusion that it is necessary to search for indicator microorganisms that can more accurately suggest the presence of pathogens. microorganisms in water than traditional indicators. The aim of the study was to justify the introduction of indicator indices of fecal contamination “generalized coliform bacteria” and Escherichia coli to assess the safety of drinking water Material and methods. The article provides an analysis of domestic and international regulatory documents and literary materials regulating the quality of drinking water in terms of sanitary and microbiological indicators and assessment criteria. The results of many years of experimental and field research carried out by research organizations and practical organizations of the Federal Service for Supervision of Consumer Rights Protection and Human Welfare are presented. Results. On the territory of Russia, “general coliform bacteria,” is one of the indicator indices chosen according to the fermentation of lactose, determine the safety of drinking water. The water does not take into account pathogenic bacteria (Salmonella, Shigella) and a number of lactose-negative opportunistic bacteria, causative agents of intestinal infections. The study of microorganisms isolated from the feces of patients confirms the frequency of occurrence of lactose-negative microorganisms to varying from 20 to 100% of strains. With an annual trend towards a decrease in the percentage of non-standard drinking water samples in terms of microbiological indices, general intestinal infections (GII) of unknown etiology increase, i.e. risk of GII. If the quality of drinking water does not correspond to thermotolerant coliform bacteria (TCB), 95% of samples contain E. coli. Therefore, the determination of E. coli more reliably indicates the intake of fresh fecal contamination and provides efficiency in taking measures to eliminate an unfavorable situation than TCB. Conclusion. Reasons are given for the introduction of more reliable microbiological indicators of water safety control, such as - “generalized coliform bacteria” with the preservation of the abbreviation GCB, combining both lactose-positive and lactose-negative bacteria, determined by the sign of glucose fermentation, negative oxidase test and negative stain according to Gram and E. coli as an indicator of recent faecal contamination, which will allow the assessment of water quality for a wide range of bacteria of the order Enterobacterials, corresponding to the modern taxonomy of Enterobacteriaceae NCBI, will ensure harmonization with international requirements and the safety of drinking water for the population.

scholarly journals The effect of container-biofilm on the microbiological quality of water used from plastic household containers

2003 ◽  
Vol 1 (3) ◽  
pp. 101-108 ◽  
Author(s):  
P. Jagals ◽  
C. Jagals ◽  
T. C. Bokako
Keyword(s):  
Heterotrophic Bacteria ◽  
Microbiological Quality ◽  
Total Coliform ◽  
Human Consumption ◽  
Microbiological Contamination ◽  
Supply Source ◽  
E Coli ◽  
Quality Of Water ◽  
Storage Containers

Studies in Southern Africa have shown that even when microbiologically safe water is supplied to developing communities at communal standpipes, contamination by high numbers of pathogenic microorganisms may occur during the processes of fetching water from the supply source and storage during use at home, rendering such waters unsafe for human consumption. This study investigated the occurrence of biofilm in PVC storage containers as one possible reason for this deterioration, using heterotrophic bacteria and total coliform counts as well as turbidity as indicators. A second objective was to determine whether biofilm in water-storage containers could contribute to hazardous microbiological contamination indicated by Escherichia coli and Clostridium perfringens. Results indicated that increased microbiological contamination is associated with biofilm. The biofilm harbours heterotrophic bacteria, total coliforms and C. perfringens. E. coli could not be associated directly with the levels of biofilm in containers but rather appears to be introduced intermittently from the ambient domestic environment. When dislodged with the biofilm, these bacteria contributed substantially to the deterioration of the microbiological quality of supplied water stored in plastic containers.

scholarly journals Comparison of four β-glucuronidase and β-galactosidase-based commercial culture methods used to detect Escherichia coli and total coliforms in water

2014 ◽  
Vol 13 (2) ◽  
pp. 340-352 ◽  
Author(s):  
Andrée F. Maheux ◽  
Vanessa Dion-Dupont ◽  
Sébastien Bouchard ◽  
Marc-Antoine Bisson ◽  
Michel G. Bergeron ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Drinking Water ◽  
Water Samples ◽  
Microbiological Quality ◽  
Total Coliform ◽  
Ease Of Use ◽  
Well Water ◽  
Positive Signal ◽  
Culture Methods ◽  
E Coli

The MI agar, Colilert®, Chromocult coliform® agar, and DC with BCIG agar chromogenic culture-based methods used to assess microbiological quality of drinking water were compared in terms of their ubiquity, sensitivity, ease of use, growth of atypical colonies and affordability. For ubiquity, 129 total coliform (representing 76 species) and 19 Escherichia coli strains were tested. Then, 635 1-L well water samples were divided into 100 mL subsamples for testing by all four methods. Test results showed that 70.5, 52.7, 36.4, and 23.3% of the non-E. coli total coliform strains and 94.7, 94.7, 89.5, and 89.5% of the 19 E. coli strains yielded a positive signal with the four methods, respectively. They also yielded a total coliform positive signal for 66.5, 51.7, 64.9, and 55.0% and an E. coli positive signal for 16.1, 14.8, 17.3, and 13.4% of the 635 well water samples tested, respectively. Results showed that Colilert® is the most expensive method tested in terms of reactants, yet it is the easiest to use. Large numbers of atypical colonies were also often observed on Chromocult coliform® and DC with BCIG, thereby challenging the target microorganism count. Thus, the MI agar method seems to be the best option for the assessment of drinking water quality.

Assessment of microbiological quality of drinking water from household tanks in Bermuda

2008 ◽  
Vol 54 (6) ◽  
pp. 495-500 ◽  
Author(s):  
B. Lévesque ◽  
D. Pereg ◽  
E. Watkinson ◽  
J.S. Maguire ◽  
L. Bissonnette ◽  
...  
Keyword(s):  
Drinking Water ◽  
Water Samples ◽  
Membrane Filtration ◽  
Microbiological Quality ◽  
General Information ◽  
Total Coliforms ◽  
E Coli ◽  
Electoral Register ◽  
Highly Correlated

Bermuda residents collect rainwater from rooftops to fulfil their freshwater needs. The objective of this study was to assess the microbiological quality of drinking water in household tanks throughout Bermuda. The tanks surveyed were selected randomly from the electoral register. Governmental officers visited the selected household (n = 102) to collect water samples and administer a short questionnaire about the tank characteristics, the residents’ habits in terms of water use, and general information on the water collecting system and its maintenance. At the same time, water samples were collected for analysis and total coliforms and Escherichia coli were determined by 2 methods (membrane filtration and culture on chromogenic media, Colilert kit). Results from the 2 methods were highly correlated and showed that approximately 90% of the samples analysed were contaminated with total coliforms in concentrations exceeding 10 CFU/100 mL, and approximately 66% of samples showed contamination with E. coli. Tank cleaning in the year prior to sampling seems to protect against water contamination. If rainwater collection from roofs is the most efficient mean for providing freshwater to Bermudians, it must not be considered a source of high quality drinking water because of the high levels of microbial contamination.

scholarly journals Fungal Load, Coliform and Aflatoxins in Wheat Flour of Lahore Metropolitan City

2020 ◽  
pp. 93-99
Keyword(s):  
Wheat Flour ◽  
Microbiological Quality ◽  
Total Coliform ◽  
Fungal Species ◽  
Coliform Bacteria ◽  
Whole Wheat Flour ◽  
Whole Wheat ◽  
Fungal Load ◽  
Wheat Flours

In Pakistan, wheat flour is mostly utilized for making flat breads locally called chapattis. Other uses of wheat flour are in bakery products manufacturing. It is an important constituent of daily diet of people. Shelf life of wheat flour is one of the most important factors for its quality determination. Wheat flour is often tainted with pathogenic fungal species and their toxic secondary metabolites called Mycotoxins. The present study was designed to make a comparative analysis of Microbiological quality (fungal load and total coliform count) and detection of aflatoxins in raw and branded whole wheat flour samples of Lahore Metropolitan city. Total 100 samples were collected for determination of fungal load, coliform and aflatoxins. The Standardized methods were applied to count the colony forming units of fungal species and total coliform bacteria respectively. The results indicated both branded and raw whole wheat flour groups were of good quality for human consumption. However, the microbiological quality of branded whole flour was better than raw whole wheat flour. There was a significant difference (P<0.05) in fungal load of raw and branded whole wheat flour. Similarly, coliform bacteria were only cultured form the samples of raw flour. In the last stage of study, aflatoxins level was analysed by using a commercially available kit. All the samples of both raw and branded whole wheat flours were negative for aflatoxins detection. The overall quality of raw and branded whole wheat flours in Lahore city is satisfactory for consumers.

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