Fecal Coliforms In Water Research Articles

Detection Of Fecal Coliforms In Water Used In Formal And Informal Food Outlets In Kasungu District, Malawi

Poor sanitary practices are common amongst many food handlers posing a health risk to consumers. Maintenance of high quality water is one of the most important aspects of ensuring consumer safety. Therefore, regular water testing is critical in public food outlets where bacterial contamination may cause outbreak of disease. The study aimed at analyzing water samples obtained from the formal and informal food outlets for the presence of fecal coliforms that are indicative of poor sanitation that result in foodborne infections amongst consumers. Using a cross-sectional design, water samples from participating food outlets (N=40) were analyzed using the membrane filtration method. Samples were filtered, under vacuum, through a cellulose acetate membrane of 0.45 μm pore size. Fecal coliforms exceeding permissible range were detected in 15 test samples (N=40). The median (IQR) concentrations of fecal coliforms (FC/100ml) in dishwashing water was 1(136) and 145(340) for the formal and informal food outlets respectively. The median (IQR) for drinking water was 0(0) with a minimum and maximum range of 0 and 14 FC/100mls. The study established a positive correlation between fecal coliforms and electrical conductivity, and total dissolved solids (p<0.05) in dish washing water used at both formal and informal food outlets. Contamination was attributed to lack of running water, poor pest control and unwholesome practices in many food outlets. Based on the study findings, it is concluded that electrical conductivity, total dissolved solids and turbidity values may be used to deduce the presence of fecal coliforms in water. The study recommends that water drawn from unprotected sources must be boiled or treated at the point of use before it can be safely used in food outlets. Periodic water testing and sanitary supervisions for all food outlets must be mandatory to ensure compliance with minimum set standards.

Prevalence of antibiotic-resistant Escherichia coli strains in selected rivers of Lesser Poland

This study aimed to determine the incidence of antibiotic-resistant strains of Escherichia coli in waters of three Lesser Poland rivers: Raba, Prądnik and Bialka. The samples were collected from 30 sites—10 from each river along their course. Membrane filtration method was used to determine the water quality based on the prevalence of fecal coliforms in water. The contaminated samples were used to isolate Escherichia coli for further studies. After confirming the systematic position of randomly isolated strains, the antibiotic resistance tests were performed using the disk-diffusion method following the recommendations of the National Reference Centre for Susceptibility Testing. Escherichia coli were present in all rivers. Complete antibiograms were obtained for 83 isolates; 30 strains originating from the Prądnik river, 37 from Raba and 16 from Bialka. A total of 67.47% strains were resistant to at least 1 tested antimicrobial (76.7% isolates from Prądnik, 73% from Raba and 37.5% from Bialka), 33.7% of all strains were resistant to at least 5 antimicrobial agents, and one strain was resistant to even 13 antibiotics. The highest resistance was observed for ampicillin and the lowest for imipenem, fosfomycin and meropenem. The obtained results showed that the resistant strains of Escherichia coli are widely spread in the water environment, even in protected areas.

The Geographic Information System applied to study schistosomiasis in Pernambuco.

ABSTRACTOBJECTIVE Diagnose risk environments for schistosomiasis in coastal localities of Pernambuco using geoprocessing techniques.METHODS A coproscopic and malacological survey were carried out in the Forte Orange and Serrambi areas. Environmental variables (temperature, salinity, pH, total dissolved solids and water fecal coliform dosage) were collected from Biomphalaria breeding sites or foci. The spatial analysis was performed using ArcGis 10.1 software, applying the kernel estimator, elevation map, and distance map.RESULTS In Forte Orange, 4.3% of the population had S. mansoni and were found two B. glabrata and 26 B. straminea breeding sites. The breeding sites had temperatures of 25ºC to 41ºC, pH of 6.9 to 11.1, total dissolved solids between 148 and 661, and salinity of 1,000 d. In Serrambi, 4.4% of the population had S. mansoni and were found seven B. straminea and seven B. glabrata breeding sites. Breeding sites had temperatures of 24ºC to 36ºC, pH of 7.1 to 9.8, total dissolved solids between 116 and 855, and salinity of 1,000 d. The kernel estimator shows the clusters of positive patients and foci of Biomphalaria, and the digital elevation map indicates areas of rainwater concentration. The distance map shows the proximity of the snail foci with schools and health facilities.CONCLUSIONS Geoprocessing techniques prove to be a competent tool for locating and scaling the risk areas for schistosomiasis, and can subsidize the health services control actions.

Effects of beach tourists on bathing water and sand quality at Puerto Velero, Colombia

Fragile coastal areas suffer from human activities. Environmental quality is one of the most important aspects in a tourist destination of sun and sand. The quality of bathing water and sand became indicators in the worldwide competition of beach destinations. We studied the water and sand quality along the beach of Puerto Velero, in northern Colombia. Water and sand beach quality were monitored during thirteen months. This allowed identifying the most significant sources of pollution along the beach, and understanding the interrelationship between tourism and the effects on the environment. Linear correlations allow assessing the association between the number of visitors and the physicochemical and microbiological parameters. The number of visitors was directly correlated with the presence of grease and oils, both in water and sand, as well as with fecal coliforms in water. A relation between the suspended solids and the presence of fecal coliforms in water and sand was observed. This statistical approach allows understanding the origin of beach sand and swimming water pollution at tourist beaches. Overall, sand quality has an important influence and is directly related to the water quality of the beach. Both the number of tourists and their activities are main factors explaining the contamination of the water and sand. This shows the importance of management of waste and wastewater in combination with awareness raising initiatives. More research should include monitoring and evaluating of both water and sand beach and provide data to revise the existing legal framework.

Faecal Coliform Levels in Mountain Streams of Winter Recreation Zones in the Cairngorms National Park, Scotland

ABSTRACTThis study aims to establish the spatial distribution of stream water faecal coliform (FC) concentrations in specific winter recreation areas in the Northern Corries of the Cairngorm Mountains, Scotland. A total of 207 water samples were collected from 10 sites during two winter seasons (2007–2008 and 2008–2009) and analysed by Colilert® 24 for the presence of FC, specifically Escherichia coli (E. coli). E. coli was not detected at Sites 1–7, above 635 m. Sites 8, 9 and 10 (below 635 m) had positive detection rates for E. coli, these being 32%, 35% and 31%, respectively. Results provide important data on the level of faecal bacteria in selected Scottish mountain streams, whilst also providing comparative benchmark data for similar studies proposed in other UK upland recreational hotspots.

Influence of seasonal and inter-annual hydro-meteorological variability on surface water fecal coliform concentration under varying land-use composition

Quantifying the influence of hydro-meteorological variability on surface source water fecal contamination is critical to the maintenance of safe drinking water. Historically, this has not been possible due to the scarcity of data on fecal indicator bacteria (FIB). We examined the relationship between hydro-meteorological variability and the most commonly measured FIB, fecal coliform (FC), concentration for 43 surface water sites within the hydro-climatologically complex region of British Columbia. The strength of relationship was highly variable among sites, but tended to be stronger in catchments with nival (snowmelt-dominated) hydro-meteorological regimes and greater land-use impacts. We observed positive relationships between inter-annual FC concentration and hydro-meteorological variability for around 50% of the 19 sites examined. These sites are likely to experience increased fecal contamination due to the projected intensification of the hydrological cycle. Seasonal FC concentration variability appeared to be driven by snowmelt and rainfall-induced runoff for around 30% of the 43 sites examined. Earlier snowmelt in nival catchments may advance the timing of peak contamination, and the projected decrease in annual snow-to-precipitation ratio is likely to increase fecal contamination levels during summer, fall, and winter among these sites. Safeguarding drinking water quality in the face of such impacts will require increased monitoring of FIB and waterborne pathogens, especially during periods of high hydro-meteorological variability. This data can then be used to develop predictive models, inform source water protection measures, and improve drinking water treatment.

Assessment of burden of virus agents in an urban sewage treatment plant in Rio de Janeiro, Brazil

Sewage discharge is considered to be the main source of virus contamination in aquatic environments. There is no correlation between the presence of viruses and the presence of fecal coliforms in water; therefore virological markers are needed when monitoring contamination. This study investigates DNA and RNA virus concentrations in wastewater and evaluates a potential virus marker of human contamination. Influent and effluent samples were collected twice a month throughout a 1-year period. Viruses were detected using quantitative polymerase chain reaction protocols; nucleotide sequencing was carried out for virus genotyping. Human adenovirus (HAdV) and polyomavirus JC (JCPyV) were the most prevalent viruses found in influent samples (100%) with a virus load that ranged from 10(6) to 10(5) genome copies per liter (gc l(-1)). Norovirus genogroup II (NoV GII) and human astrovirus (HAstV) were less prevalent, and ranged from 10(4) to 10(3)gc l(-1). Quantitative data on virus profiles in wastewaters stress the high level of rotavirus species A environmental dissemination and address the potential of HAdV as a useful virological marker of virus contamination in aquatic environments. This study corroborates other studies performed in developed countries on DNA viruses as good markers of human fecal contamination.

Comparación de métodos para el análisis de coliformes totales y fecales en muestras de agua mediante la técnica de Número Más Probable (NMP)

El análisis microbiológico básico del agua comprende la determinación de coliformes totales y fecales. La ausencia o presencia de los coliformes fecales en el agua define su potabilidad. El objetivo del presente estudio consistió en el diseño y ejecución de un esquema de comparación de dos técnicas para la determinación de coliformes en aguas, a partir de modificaciones aplicadas sobre la técnica de referencia de Número Más Probable (NMP) derivada del Standard Methods for the Examination of Water and Wastewater. Específicamente, las modificaciones incluyeron el tipo de medio utilizado en la fase presuntiva de la técnica y el uso de incubadora de aire, alternativo al baño de maría en la fase confirmatoria. Simultáneamente, se comparó el efecto del uso de equipo volumétrico tipo micropipeta automática calibrada o pipetas de vidrio estériles calibradas. Para tal efecto, se utilizaron muestras de agua artificiales, elaboradas con material del laboratorio e inoculadas con una cepa de Escherichia coli ATCC 25922 así como muestras ambientales. La metodología alternativa tiene un rendimiento superior solamente cuando el nivel de inóculo en las muestras es bajo. No se determinó ninguna diferencia estadísticamente significativa entre los dos sistemas de medición volumétrica.

Microbiological quality of Ulva lactuca and Ulva clathrate (Chlorophyta) along the coastline of La Paz, B.C.S., México.

Total, fecal coliforms and the enterococcus group in Ulva lactuca and U. clathrata were measured in four localities of the coastline of La Paz, B.C.S, Mexico. Levels of fecal coliforms in water were below the standard of the Ecological Criteria of Water Quality(EC-WQ) which indicates a healthy La Paz inlet (below 200 MPN/100ml). Values of fecal coliforms in algae were below the NOM-031-SSA1-1993 levels determined for marine organisms destined for human consumption. These values were high only in few months. No enterococci were detected in thesamples.

Swimming in Sewage: Indicators of Faecal Waste on Fish in the Saint John Harbour, New Brunswick

Abstract Despite increased recognition of the risks to the health of humans and the environment, untreated municipal wastewaters are still discharged into waterways worldwide. One of the primary concerns related to its discharge into surface waters is the risk to human health through the transmission of pathogens associated with faecal matter. Saint John, New Brunswick, is one of the few Canadian cities that still releases untreated sewage into its urban waterways and harbour. Water faecal coliform levels, an indicator of faecal waste and associated pathogens, are well above recreational guidelines in some of these areas. Although it is not encouraged by the municipality, recreational fishing occurs in these areas and this raises concerns regarding the potential for disease transmission during the handling of these fish. To investigate the potential for fish to be a vehicle of pathogen transmission to humans, the skin of wild fishes (smelt, Osmerus mordax, and mummichog, Fundulus heteroclitus) and caged mummichog was sampled for faecal coliforms from several sites in Saint John between August and November of 2005. Water faecal coliform levels at sites used for caging studies and wild fish collections, and the duration of caging were compared with the number of faecal coliforms on the surface of the fish. Skin samples from the two fish species collected from the wild indicated elevated levels of fecal coliforms in some locations. Both wild and caged fish showed that the amount of faecal coliform on fish skin is influenced by the water faecal coliform levels.

Comparing artificial neural networks and regression models for predicting faecal coliform concentrations

This paper compares the performance of ordinary least squares (OLS) and binary logistic regression methods, and artificial neural networks (ANNs) for the prediction of surface water faecal coliform concentrations in a 8.2 km2 mixed land-use watershed. Model inputs consist of precipitation and temperature data, as well as instantaneous measurements of streamflow and conductivity. The ANNs are able to correctly classify 69% and 85% of faecal coliform concentrations relative to 20 and 200 cfu/100 mL water quality standards, respectively, results moderately better than those observed for the regression models. The ANN models using only meteorological inputs were able to correctly classify 72% and 81% of the observations relative to the 20 and 200 cfu/100 mL standards, respectively. The ANN models are notably better at predicting when the 200 cfu/100 mL standard is violated. In addition, the ANN models have lower percentages of false negatives, a characteristic desirable for protection of public health.

Identification of Fecal Escherichia coli from Humans and Animals by Ribotyping

Fecal pollution of water resources is an environmental problem of increasing importance. Identification of individual host sources of fecal Escherichia coli, such as humans, pets, production animals, and wild animals, is prerequisite to formulation of remediation plans. Ribotyping has been used to distinguish fecal E. coli of human origin from pooled fecal E. coli isolates of nonhuman origin. We have extended application of this technique to distinguishing fecal E. coli ribotype patterns from human and seven individual nonhuman hosts. Classification accuracy was best when the analysis was limited to three host sources. Application of this technique to identification of host sources of fecal coliforms in water could assist in formulation of pollution reduction plans.

Dip slide technique for rapid qualitative estimation of fecal coliforms in water and wastewater

A simple, rapid, inexpensive method for qualitative estimation of fecal coliforms (FC) in water and wastewaters is presented. The estimation of FC by the dip slide technique (DST) gives results within 8 h. The DST is compared with the conventional membrane filter (MF) procedure. The efficacy of the proposed technique is evaluated by statistical analysis.

Quantitative determination of E. coli, and fecal coliforms in water using a chromogenic medium

A new medium, Chromocult Coliform® Agar (CC agar) developed by E. Merck AG (Darmstadt, Germany) was compared with the Standard Methods, membrane filtration fecal coliform (mFC) medium for fecal coliform detection and enumeration. In the CC agar, non‐E. coli, fecal coliforms (Klebsiella, Enterobacter, and Citrobacter,), (KEC) were identified by the production of a salmon to red colour from p‐galactosidase (LAC) cleavage of the substrate Salmon‐GAL, while E. coli, colonies were detected by the blue colour, produced by the cleavage of X‐glucuronide by β‐ glucuronidase (GUS). Statistically, there was no significant differences between fecal coliform counts obtained with the two media (CC agar and mFC agar) and two incubation procedures (2h‐37°C plus 22h‐44.5°, and 44.5°C) as determined by variance analysis. In our study K coli, represented, on average 70.5–92.5% of the fecal coliform population. A high incidence of false negative KEC (19.5%) and E. coli, (29.6%) colonies was detected at 44.5°C. Two K coli, GUS negative phenotype upon reinoculation into CC agar were GUS+. A total of 31 KEC LAC colonies were streaked onto CC, agar and incubated at 37°C, 29 KEC strains that failed to produce β‐galactosidase at 44.5°C were able to produce the enzyme at 37°C. In our opinion the physiological condition of the fecal coliform isolates could be responsible for the non‐expression of P‐galactosidase and P‐glucuronidase activities at 44.5°C.

Comparative evaluation of modified m-FC and m-TEC media for membrane filter enumeration of Escherichia coli in water

Two media used to detect fecal coliforms in water by membrane filtration, m-FC and m-TEC, were modified and supplemented with the chromogenic substrate 5-bromo-6-chloro-3-indoyl-beta-D-glucuronide (BCIG) and were compared for quantitative recovery of Escherichia coli. Student's t test of data from 181 water samples of sewage, rivers, lakes, and wells did not demonstrate any statistically significant differences (P = 0.05) in the enumeration of E. coli with these media. Target colonies were confirmed to be E. coli at rates of 98.6 and 97.3% by using FC-BCIG and TEC-BCIG media, respectively. Glucuronidase-negative isolates of E. coli were encountered at the same frequency (6.0%) on both media. This collaborative study demonstrated that either modified basal medium could be used successfully for detection of E. coli in various nontreated waters within 24 h.

The Effect of Indicator Organisms in Wash Water Disposal on Mooring Embayments

With the increase in the number of recreational boats in Ontario's waterways, there is growing concern that discharges of wash water may be causing local water quality problems. Bacterial loadings were determined from measurements on a sailboat, power cruiser, and houseboat over a period of 15 to 18 days. Composition of the boat crews was changed three times. There were 286 samples analyzed. The receiving water impact of the wash water discharges was measured in three confined embayment anchorages. The range of freshwater use was between 17 and 22 L/person/day. The geometric range of fecal coliform (FC) densities was found to be in the 10 5 to 10 8/100 mL, however the Escherichia coli component of the fecal coliform component was only 6 percent. Wash water discharge loadings could cause the receiving water fecal coliform densities to exceed 100FC/100 mL in two of the three embayments studies, however the public health significance of the findings is questionable. Receiving water bacterial densities are functions of the number of boats, size of the embayment, and the water exchange in and out of the embayment. A predictive model was developed.

Fecal coliform loadings and stocks in buttermilk bay, Massachusetts, USA, and management implications

Abundance of fecal caliform bacteria is a weak index of the presence of human pathogens in wastewater entering coastal waters. In spite of this, use of fecal caliform indices for management purposes is widespread. To gain insight into interpretation of fecal coliform data, we evaluated size of stocks of fecal coliforms in water, sediments, and sea wrack, in Buttermilk Bay, a coastal embayment in Massachusetts. Sediments contained most of the fecal coliforms. Fecal coliforms in sediments were as much as one order of magnitude more abundant than in the water column or in sea wrack. The fecal coliforms in sediments of Buttermilk Bay were so abundant that resuspension of fecal coliforms from just the top 2 cm of muddy sediments could add sufficient cells to the water column to have the whole bay exceed the federal limit of fecal coliforms for shellfishing. The major sources of fecal coliforms to the bay were water-fowls, surface runoff, groundwater, and streams. Waterfowl were the largest source of fecal coliforms during cold months; surface runoff, streams, and groundwater were most important during warm months. Redirection of surface runoff pipes is unlikely to be a very successful management action since contributions via this source are insufficient to account for the measured increases in concentrations of fecal coliforms in water. Removal of waterfowl is also unlikely to be useful, since fecal coliform concentrations leading to closures of shellfish beds and swimming areas are most frequent during warm months when waterfowl are rarest. Rates of loss of fecal caliform cells from the water column by death and tidal exchange were high. Mortality of cells was about an order of magnitude larger than losses by tidal exchange. The amounts of fecal coliforms brought into the bay by waterfowl, surface runoff, groundwater, and streams are an order of magnitude smaller than the losses by mortality and tidal removal. This implies that there is an additional source of fecal coliforms within the bay. We suggest that resuspension of the upper layers of sediments can easily account for the fecal coliforms present in the water. Fecal coliform content of water and shellfish were not correlated. In contrast, sediment and shellfish fecal coliform abundances were significantly related. Monitoring of fecal coliforms in sediments may provide a better assessment of shellfish than sampling of water. The large fecal coliform stock in sediments should be the first priority for management. Efforts ought to be directed toward the reduction of sediment fecal coliform stocks. Lowering nutrient additions to coastal water bodies may be one practical approach.

Evaluation of the 7-h membrane filter test for quantitation of fecal coliforms in water

The 7-h fecal coliform (FC) test for detection of FC organisms in water was evaluated to establish its validity and usefulness for emergency and disaster situations. The waters tested consisted of routine samples collected for public health surveillance and enforcement purposes. A total of 984 water samples from throughout California were assayed. These included samples from coastal salt waters, rivers, canals, and reservoirs, in addition to potable and miscellaneous freshwater sources. A portion of each sample was tested concurrently by both the 7-h FC test and the most-probable-number FC five-tube test. The 7-h FC test samples were incubated for 7 to 7.25 h at 41.5 degrees C. Overall, greater than 90% agreement was obtained between the methods in determining whether the water quality was acceptable or unacceptable. Statistical analysis of the 984 samples confirmed that the 7-h FC method was a suitable alternative to the most-probable-number FC method for evaluation of freshwater samples. During emergencies or disasters, the 7-h FC test could provide a means for detection of fecal contamination of water with results available in less than 1 day.

Detection of fecal coliforms in water by using [14C]mannitol

Interest in rapid bacterial detection methods for sanitary indicator bacteria in water prompted a study of the use of [U-14C]mannitol to detect fecal coliforms (FC). A simple method which used m-FC broth, membrane filtration, and two-temperature incubation (35 degrees C for 2 h followed by 44.5 degrees C for 2.5 h) was developed. [U-14C]mannitol was added to the medium, and the temperature was raised to 44.5 degrees C after 2 h at 35 degrees C. 14CO2 was collected as Ba14CO3 and assayed by liquid scintillation spectroscopy. Correlations were examined between FC cell numbers at the start of incubation (standard 24-h FC test) and Ba14CO3 counts per minute after 4.5 h. Results indicated that FC numbers ranging from 1 x 10(1) to 2.1 x 10(5) cells could be detected in 4.5 h. Within-sample reproducibility at all cell concentrations was good, but sample-to-sample reproducibility was variable. Comparisons between m-FC broth and m-FC broth modified by substituting D-mannitol for lactose indicated that the standard m-FC broth was the better test medium. Results from experiments in which dimethyl sulfoxide was used to increase permeability of FC to [U-14C]mannitol indicated no increase in 14CO2 production due to dimethyl sulfoxide. Detection of FC by this method may be useful for rapid estimation of FC levels in freshwater recreational areas, for estimating the quality of potable source water, and potentially for emergency testing of potable water, suspected of contamination due to distribution line breaks or cross-connections.

Rapid detection of total and fecal coliforms in water by enzymatic hydrolysis of 4-methylumbelliferone-beta-D-galactoside.

Three fluorogenic methylumbelliferone (MU) substrates were evaluated for rapid detection of total and fecal coliform bacteria (TC and FC) in drinking water. 4-MU-beta-D-galactoside, MU-heptanoate, and MU-glucuronide were used to determine enzyme activity as a surrogate measure of coliform concentration. Coliforms occurring in river water and in potable water artificially contaminated with raw sewage were tested. The initial rate of hydrolysis (delta F) of MU-beta-D-galactoside showed promise as an indicator of TC and FC within 15 min. delta F of MU-glucuronide was insufficient in the 15-min assay, and combinations of the MU substrates did not enhance delta F. A direct membrane filter method incorporating MU-beta-D-galactoside into an agar medium allowed the detection of as few as 1 FC per 100 ml within 6 h.