scholarly journals Pollution Physique Et Bactériologique De L’eau Du Fleuve Dans La Basse Vallée De L’ouémé Pendant Les Périodes De Basses Et Hautes Eaux Au Bénin

2017 ◽  
Vol 13 (33) ◽  
pp. 167
Author(s):  
Adjagodo A. ◽  
Agassounon Djikpo Tchibozo M. ◽  
Kelomè N.C. ◽  
Vissin E.W. ◽  
Agbossou E.
Keyword(s):  
Water Samples ◽  
Membrane Filtration ◽  
High Water ◽  
Total Coliforms ◽  
E Coli ◽  
Sampling Campaign ◽  
High Water Period ◽  
Thermotolerant Coliforms

The objective of this study is to assess the water river quality of the Lower Valley of Ouémé in Benin. Two river water sampling campaigns were carried out during low and high water. At each sampling campaign, eleven (11) sampling sites were selected and at each site four samples were taken, making a total of 44 water samples. Hydrogen potential, dissolved oxygen, suspended matter and turbidity were measured in situ. Fecal contamination germs such as total coliforms, thermotolerant coliforms, Escherichia coli and fecal enterococci were counted by the membrane filtration technique. The results of the physical analyzes reveal that the pH measured in the water samples conformed to the WHO standard except turbidity. The results of the bacteriological analyzes in 100 mL of water sample of the river reveal average bacterial loads in periods of low and high waters which vary respectively from 2.57.10 2 ± 451 CFU and 3.35.102 ± 459 CFU for total coliforms; 1.42.102 ± 315 CFU and 1.55.102 ± 251 for thermotolerant coliforms; 0,79.102 ± 216 CFU and 1.55.102 ± 251 for E. coli. The Enterococci are absent in the waters during these two periods. The high burden of these germs counted in the high water period may be due runoff phenomenon and unhygienic behavior observable in the study area.

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.

Microbial Quality of Water Supply to an Urban Community in Trinidad

2002 ◽  
Vol 65 (8) ◽  
pp. 1297-1303 ◽  
Author(s):  
LAVAUGHN AGARD ◽  
CORLIS ALEXANDER ◽  
SIMONE GREEN ◽  
MICHAEL JACKSON ◽  
SANJEEV PATEL ◽  
...  
Keyword(s):  
Drinking Water ◽  
Water Samples ◽  
Residual Chlorine ◽  
Reservoir Water ◽  
Total Coliforms ◽  
E Coli ◽  
Significant Difference ◽  
Thermotolerant Coliforms ◽  
The Difference

A microbiological study was conducted to determine the quality of the water supply to an urban community in San Fernando proper in south Trinidad using total coliforms and thermotolerant coliforms as indicators of water pollution. The membrane filter technique was used to detect total coliforms and thermotolerant coliforms on endo agar and MFc agar, respectively. The residual chlorine levels in water from the reservoir, from standpipes along the distribution line, and from households were determined with a commercial test kit. Of a total of 104 drinking water samples obtained from households, 84 (80.8%), 56 (53.8%), and 70 (67.3%) tested positive for total coliforms, thermotolerant coliforms, and Escherichia coli, respectively. The difference was statistically significant (P < 0.05, χ2). Of the 81 water samples collected from the Water and Sewerage Authority (WASA) main supply to households, 38 (46.9%), 13 (16.0%), and 27 (33.3%) were contaminated by total coliforms, thermotolerant coliforms, and E. coli, respectively, and the difference was statistically significant (P < 0.05, χ2). Eight (20.5%) of 39 water samples from standpipes along the distribution line tested positive for total coliforms, compared with 4 (10.3%) samples testing positive for thermotolerant coliforms. All five samples of treated water obtained from the reservoir tested negative for coliforms. There was a significant difference (P = 0.004) in the mean residual chlorine levels in water from the reservoir, water from standpipes, and water from households. Similarly, as the level of residual chlorine decreased, there was a statistically significant (P = 0.004) increase in the prevalence of total coliforms in water from 0.0% (treated reservoir water) to 15.2% (standpipe) to 53.5% (household mains) to 80.0% (household drinking water). There was also a statistically significant difference (P < 0.001, χ2) in the prevalence of total coliforms in drinking water and in water from the WASA main supply to households. Of the 105 E. coli strains tested, 7 (6.7%), 16 (15.2%), and 22 (21.0%) were mucoid, hemolytic, and non–sorbitol fermenters, respectively. It was concluded that the high degree of contamination of drinking water in households poses a health hazard to consumers.

scholarly journals Are the defined substrate-based methods adequate to determine the microbiological quality of natural recreational waters?

2009 ◽  
Vol 8 (1) ◽  
pp. 11-19 ◽  
Author(s):  
Marta Sofia Valente ◽  
Paulo Pedro ◽  
M. Carmen Alonso ◽  
Juan J. Borrego ◽  
Lídia Dionísio
Keyword(s):  
Standard Method ◽  
Membrane Filtration ◽  
Microbiological Quality ◽  
Recreational Waters ◽  
Total Coliforms ◽  
E Coli ◽  
Quality Of Water ◽  
Routine Monitoring ◽  
Rapid Tests

Monitoring the microbiological quality of water used for recreational activities is very important to human public health. Although the sanitary quality of recreational marine waters could be evaluated by standard methods, they are time-consuming and need confirmation. For these reasons, faster and more sensitive methods, such as the defined substrate-based technology, have been developed. In the present work, we have compared the standard method of membrane filtration using Tergitol-TTC agar for total coliforms and Escherichia coli, and Slanetz and Bartley agar for enterococci, and the IDEXX defined substrate technology for these faecal pollution indicators to determine the microbiological quality of natural recreational waters. ISO 17994:2004 standard was used to compare these methods. The IDEXX for total coliforms and E. coli, Colilert®, showed higher values than those obtained by the standard method. Enterolert® test, for the enumeration of enterococci, showed lower values when compared with the standard method. It may be concluded that more studies to evaluate the precision and accuracy of the rapid tests are required in order to apply them for routine monitoring of marine and freshwater recreational bathing areas. The main advantages of these methods are that they are more specific, feasible and simpler than the standard methodology.

scholarly journals Microbiological and physico-chemical characterisation of well water in the town of Korhogo, Côte d’Ivoire

2021 ◽  
Vol 15 (3) ◽  
pp. 1264-1275
Author(s):  
Ollo Kambire ◽  
Konan Mathurin Yao ◽  
Sampah Georges Eblin ◽  
Diegon Arnaud Romain Tokpa ◽  
Rose Koffi-Nevry
Keyword(s):  
Water Samples ◽  
Membrane Filtration ◽  
Anaerobic Bacteria ◽  
Living Organism ◽  
Human Consumption ◽  
Well Water ◽  
Total Coliforms ◽  
Spectrophotometric Methods ◽  
Physico Chemical

Water is essential to the life of every living organism. The water used by the consumer must be safe for the preservation of his health. The objective of this study was to assess the quality of well water used in households in the city of Korhogo. To do this, water samples were taken from the wells of different households. Parameters such as pH, temperature, electrical conductivity and total dissolved solids were measured at the sampling sites. Nitrates and ammonium were determined by spectrophotometric methods using sodium salicylate and indophenol blue, respectively. The membrane filtration technique has been used for the enumeration of total coliforms, Escherichia coli, fecal enterococci, sulfite-reducing anaerobic bacteria, yeasts and moulds. The agar incorporation method was used for the enumeration of mesophilic aerobic germs. The non-conformity relative to pH was 73%. All wells were contaminated with nitrates and ammonium. Non-compliance rates of 80% and 53% were obtained for nitrates and ammonium respectively. Non-compliance with mesophilic aerobic germs, total coliforms, E. coli and fecal enterococci was 100% for each indicator. No spore of sulphite-reducing clostridia has been identified. Contamination rates of 80% (mould) and 67% (yeast) were recorded. The moulds isolated from the various water samples belong to the genus Aspergillus. The quality of well water in households is not suitable for human consumption. These waters require treatment or household residents must switch to other safe sources of drinking water.

scholarly journals Microbiological quality assessment of fresh tilapia marketed in the Federal District and of the ice used for its conservation

2022 ◽  
Vol 17 (12) ◽  
Author(s):  
Ana Carolina Almeida de Oliveira Ferreira ◽  
Erika da Silva Monteiro ◽  
David de Oliveira Sousa ◽  
Calliandra Maria de Souza Silva ◽  
Izabel Cristina Rodrigues Da Silva ◽  
...  
Keyword(s):  
Molecular Analysis ◽  
Microbiological Quality ◽  
Federal District ◽  
Production Chain ◽  
Total Coliforms ◽  
E Coli ◽  
Psychrotrophic Bacteria ◽  
Thermotolerant Coliforms

Tilapia (Oreochromis niloticus) is the most cultivated and consumed freshwater fish in Brazil. The present study aimed to evaluate the microbiological quality of ice and fresh tilapia samples commercialized in the Federal District. Tilapia samples were tested for counts of mesophilic and psychrotrophic bacteria, determination of total and thermotolerant coliforms, Staphylococcus aureus counts and presence of Salmonella. Ice samples were analyzed for determination of total coliforms and thermotolerant coliforms and presence of Escherichia coli. Of the 20 samples of fresh tilapia analyzed, ten samples (50%) presented Salmonella (genetically confirmed through the presence of the invA gene) and, therefore, were unfit for consumption. S. aureus was found in 11 samples (55%), and one sample of fillet presented S. aureus counts (3.15 CFU/g) above the limit allowed by Brazilian legislation (3 log CFU/g). S. aureus colonies were confirmed by detection of CoA gene in molecular analysis. Of the 14 ice samples analyzed, 12 samples (85.7%) were unfit for use in fish conservation due to the presence of total coliforms and 9 ice samples (64.3%) were also contaminated with thermotolerant coliforms. E. coli was isolated from 6 ice samples (42.9%) and confirmed in the molecular analysis through the amplification of the MalB gene. In conclusion, the high contamination of tilapia samples with Salmonella and of the ice used for its conservation with coliforms and E. coli indicates the need for better hygienic practices in the tilapia production chain, to increase its quality and microbiological safety.

scholarly journals Physicochemical and biological quality of groundwater sources in Kadama Sub county, Kibuku District

2021 ◽  
Author(s):  
Abel Wilson Walekhwa ◽  
Frederick Oporia ◽  
Ali Halage ◽  
Douglas Bulafu ◽  
Aisha Nalugya ◽  
...  
Keyword(s):  
Risk Factors ◽  
Water Samples ◽  
Membrane Filtration ◽  
Water Sources ◽  
Human Consumption ◽  
Surrounding Water ◽  
Cross Sectional ◽  
E Coli ◽  
Biological Quality

Abstract IntroductionWater should comply with standard/regulatory physio-chemical and biological parameters to ensure that it is safe for domestic use. We therefore sought to assess the physico-chemical and biological quality of groundwater sources in Kadama subcounty, Kibuku district, Eastern Uganda. MethodsA cross-sectional quantitative study was conducted. We collected water samples from twenty-three functional water sources. We assessed the turbidity, pH and presence of Escherichia coli (E. coli) using the turbidity meter, pH meter and membrane filtration technique, respectively. Furthermore, physical sanitary inspection of the water sources was done using a standard pretested observational checklist to assess existing risk factors.ResultsThe majority, 69.5% of the water sources included in the study were boreholes, with about 43.5% of them from Nandere parish. Majority of the water sources 86.9% (20/23) had clogged/blocked drainage channels, about a third of water sources 60.9% (14/23) did not have fences/protection around them and majority of the water sources, 82.6% (19/23) had stagnated apron. Some water sources 8.7% (2/23) had open defecation around them. The water samples had a mean pH of 6.87 (SD 0.920) with 4.4% acidic, 86.9% normal/acceptable pH level and 8.6% in alkaline state. About two-thirds (65.3%) of these water sources had turbidity levels less than 5 NTUs. In addition, boreholes had a better turbidity score of 81.2% (13/16) compared to the water wells 71.4% (5/7). About half, 43.5% of the water sources were above the WHO recommended range of zero coliforms. ConclusionsSome ground water sources had sanitary risk factors and significant levels of E. coli which makes them unfit for human consumption, though they can be used for other domestic purposes including washing clothes. This calls for urgent need to keep surrounding water sources clean and continuously disinfect drinking water from groundwater sources before human consumption.

scholarly journals Microbiological Contamination of Strawberries from U-Pick Farms in Guangzhou, China

2019 ◽  
Vol 16 (24) ◽  
pp. 4910
Author(s):  
Xiaohong Wei ◽  
Shuiping Hou ◽  
Xinhong Pan ◽  
Conghui Xu ◽  
Juntao Li ◽  
...  
Keyword(s):  
Irrigation Water ◽  
Water Samples ◽  
Southern China ◽  
Microbiological Quality ◽  
Metropolitan Region ◽  
Microbiological Contamination ◽  
Total Coliforms ◽  
E Coli ◽  
Quality Of Irrigation Water

This study quantified the association of rodent fruit damage and the microbiological quality of irrigation water on the risk of microbiological contamination of strawberries collected from 18 U-pick farms across five different districts in the Guangzhou metropolitan region of southern China. Fifty-four composite strawberries samples, with or without evidence of rodent or avian foraging damage (i.e., bitten), along with 16 irrigation water samples, were collected during the spring of 2014 and winter of 2015 from our cohort of 18 farms. Composite strawberry samples and irrigation water were analyzed for total coliforms, E. coli, Salmonella, E. coli O157, Giardia, and Cryptosporidium. Total coliforms and E. coli were detected in 100% and ~90% of irrigation water samples, respectively. In contrast, Cryptosporidium was detected in only two water samples, while Salmonella, E. coli O157, and Giardia were not detected in any water samples. Strawberries with signs of being bitten by wildlife had significantly higher concentrations of total coliforms and E. coli, compared to strawberries with no physical evidence of rodent damage (p < 0.001). Similarly, Cryptosporidium was detected in 7/18 (39%) of bitten, 4/18 (22%) of edge, and 5/18 (28%) of central strawberry samples, respectively. Concentration of E. coli on strawberries (p < 0.001), air temperature (p = 0.025), and presence of Cryptosporidium in irrigation water (p < 0.001) were all associated with the risk of Cryptosporidium contamination on strawberries. Salmonella and Giardia were detected in <4% strawberry samples and E. coli O157 was not detected in any samples. These results indicate the potential food safety and public health risks of consuming unwashed strawberries from U-pick farms, and the need for improved rodent biosecurity of U-pick strawberry fields and enhanced microbiological quality of irrigation water used at these facilities.

scholarly journals Physicochemical and biological quality of groundwater sources in Kadama Sub county, Kibuku District

2021 ◽  
Author(s):  
Abel Wilson Walekhwa ◽  
Frederick Oporia ◽  
Ali Halage ◽  
Douglas Bulafu ◽  
Solomon Tsebeni Wafula ◽  
...  
Keyword(s):  
Risk Factors ◽  
Water Samples ◽  
Membrane Filtration ◽  
Water Sources ◽  
Human Consumption ◽  
Surrounding Water ◽  
Cross Sectional ◽  
E Coli ◽  
Biological Quality

Abstract IntroductionWater should comply with standard/regulatory physio-chemical and biological parameters to ensure that it is safe for domestic use. We therefore sought to assess the physico-chemical and biological quality of groundwater sources in Kadama subcounty, Kibuku district, Eastern Uganda.MethodsA cross-sectional quantitative study was conducted. We collected water samples from twenty-three functional water sources. We assessed the turbidity, pH and presence of Escherichia coli (E. coli) using the turbidity meter, pH meter and membrane filtration technique, respectively. Furthermore, physical sanitary inspection of the water sources was done using a standard pretested observational checklist to assess existing risk factors.ResultsThe majority, 69.5% of the water sources included in the study were boreholes, with about 43.5% of them from Nandere parish. Majority of the water sources 86.9% (20/23) had clogged/blocked drainage channels, about a third of water sources 60.9% (14/23) did not have fences/protection around them and majority of the water sources, 82.6% (19/23) had stagnated apron. Some water sources 8.7% (2/23) had open defecation around them. The water samples had a mean pH of 6.87 (SD 0.920) with 4.4% acidic, 86.9% normal/acceptable pH level and 8.6% in alkaline state. About two-thirds (65.3%) of these water sources had turbidity levels less than 5 NTUs. In addition, boreholes had a better turbidity score of 81.2% (13/16) compared to the water wells 71.4% (5/7). About half, 43.5% of the water sources were above the WHO recommended range of zero coliforms.ConclusionsSome ground water sources had sanitary risk factors and significant levels of E. coli which makes them unfit for human consumption, though they can be used for other domestic purposes including washing clothes. This calls for urgent need to keep surrounding water sources clean and continuously disinfect drinking water from groundwater sources before human consumption.

scholarly journals Microbiological contamination of water pans in Baringo County

2017 ◽  
Vol 7 (3) ◽  
pp. 485-494
Author(s):  
Edith J. Kurui ◽  
George M. Ogendi ◽  
Wilkister N. Moturi
Keyword(s):  
Water Samples ◽  
Membrane Filtration ◽  
Microbial Contamination ◽  
Total Coliforms ◽  
E Coli ◽  
Quality Guidelines ◽  
Significant Difference ◽  
Significant Spatial Variation ◽  
Dry Seasons ◽  
Filtration Technique

Water pans constitute the main source of rural water supply in Baringo County. This study sought to assess the spatial-temporal variation of total coliforms, Escherichia coli, Fecal streptococcus and Salmonella species in the water pans. A sanitary survey was conducted to observe the potential sources of microbial contamination on the water pans. Water was sampled from one protected and five unprotected water pans (n = 6) in the study area for a period of 4 months (June–October 2015). A total of 72 water samples were sampled in triplicate from the water pans for microbial analyses, membrane filtration technique was used in assaying for microbial counts of total coliforms, E. coli, F. streptococcus and Salmonella species in water samples. The results show that there was a significant spatial variation in F. streptococcus amongst the protected and the unprotected water pan sampled sites (p = 0.008), and there was a statistically temporal significant difference (p = 0.001) for total coliforms and Salmonella species during the dry seasons, respectively. Given the prevalence of the selected diseases causing pathogens in water above the WHO drinking water quality guidelines, households are advised to treat the water before use.

An Improved Membrane Filtration Method for Enumeration of Faecal Coliforms and E. Coli by a Fluorogenic β-Glucuronidase Assay

1993 ◽  
Vol 27 (3-4) ◽  
pp. 267-270 ◽  
Author(s):  
M. T. Augoustinos ◽  
N. A. Grabow ◽  
B. Genthe ◽  
R. Kfir
Keyword(s):  
Escherichia Coli ◽  
Water Samples ◽  
Membrane Filtration ◽  
Faecal Coliforms ◽  
Environmental Waters ◽  
Filtration Method ◽  
E Coli ◽  
Wide Range ◽  
Pure Cultures ◽  
Glucuronidase Assay

A fluorogenic β-glucuronidase assay comprising membrane filtration followed by selective enumeration on m-FC agar at 44.5°C and further confirmation using tlie 4-metliylumbelliferyl-β-D-glucuronide (MUG) containing medium was evaluated for the detection of Escherichia coli in water. A total of 200 typical blue and non-typical blue colonies were isolated from sea and fresh water samples using initial selective enumeration on m-FC agar. Pure cultures of the selected colonies were further tested using the MUG assay and identified using the API 20E method. Of the colonies tested which were shown to be positive using the MUG assay 99.4% were Escherichia coli. The results of this study indicate the combination of the m-FC method followed by the MUG assay to be highly efficient for the selection and confirmation of E. coli from a wide range of environmental waters.

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