Isolation and enumeration of faecal streptococci from nile water (1975–1976)

1980 ◽  
Vol 14 (12) ◽  
pp. 1669-1678 ◽  
Author(s):  
Fayek A. Saleh
Keyword(s):  
Nile Water ◽  
Faecal Streptococci

Applying Bacteriological Parameters for Evaluating Underground Water Quality

1988 ◽  
Vol 20 (11-12) ◽  
pp. 425-428 ◽  
Author(s):  
H. T. El-Zanfaly ◽  
A. M. Shabaan
Keyword(s):  
Water Quality ◽  
Drinking Water ◽  
Water Samples ◽  
Anaerobic Bacteria ◽  
Underground Water ◽  
Faecal Coliforms ◽  
Bacterial Pollution ◽  
Important Approach ◽  
Positive Results ◽  
Faecal Streptococci

A total of 111 water samples were drawn from 15 wells. These samples were subjected to bacteriological examinations to determine the suitability of the monitored wells as source for drinking water. Significant levels of bacterial pollution indicators were detected in the underground water samples during the period of study. Total bacterial counts ranged between 10-104CFU/ml. Faecal streptococci was the most common and detected in 9 6% of water samples. Lower percentages of samples (92, 55 and 45%) were contaminated with total coliforms, faecal coliforms and total clostridia, respectively. Faecal coliforms: faecal streptococci was less than 0.7 in 86% of the examined samples. Anaerobic bacteria were detected in the examined well water samples. Only 101 water samples were tested for anaerobic spore-formers and all showed positive results. Most examined wells do not meet the water quality standards for drinking water. Accordingly, the necessity of controllin bacterial pollution in ground-water through disinfection was clearly confirmed. Testing the underground water for more than one indicator represents an important approach for water quality assurance.

The relationship between health effects in triathletes and microbiological quality of freshwater

1995 ◽  
Vol 31 (5-6) ◽  
pp. 19-26 ◽  
Author(s):  
G. J. Medema ◽  
I. A. van Asperen ◽  
J. M. Klokman-Houweling ◽  
A. Nooitgedagt ◽  
M. J. W. van de Laar ◽  
...  
Keyword(s):  
Water Quality ◽  
Geometric Mean ◽  
Microbiological Quality ◽  
Quality Parameters ◽  
Health Complaints ◽  
E Coli ◽  
Thermotolerant Coliforms ◽  
Microbiological Water Quality ◽  
The Relationship ◽  
Faecal Streptococci

This pilot study was carried out to determine the relationship between microbiological water quality parameters and the occurrence of health complaints among triathletes. Data were collected at an Olympic distance triathlon (n=314) and a run-bike-run (n=81; controls for exposure to fresh water). At the time of the triathlon, the concentrations of Escherichia coli , thermotolerant coliforms, faecal streptococci, entero- and reoviruses, F-specific RNA phages, Salmonella, Campylobacter, Aeromonas, Plesiomonas shigelloides, Pseudomonas aeruginosa and Staphylococcus aureus were examined over the swimming course. Information on the occurrence of health complaints during the competition and in the week thereafter was collected through a written questionnaire. The results show that triathletes and run-bike-runners are comparable with respect to factors other than water exposure (age, sex, training history, physical stress, lower intestinal health complaints during the competition) that may influence the occurrence of health complaints in the week after the competition. Triathletes and run-bike-runners reported gastro-intestinal (7.7% vs 2.5%), respiratory (5.5% vs 3.7%), skin/mucosal (2.6% vs 1.2%), general (3.5% vs 1.2%) and total symptoms (14.8% vs 7.4%) in the week after the event. The health risks for triathletes for all symptom groups are not significantly higher than for run-bike-runners. The geometric mean concentration of faecal indicator bacteria is relatively low: E. coli 170/100 ml; faecal streptococci 13/100 ml, enteroviruses were present at concentrations of 0.1/l. The group of triathletes was homogeneusly and relatively intensely exposed to water; they all swam in the same body of water at the same time and 75% reported to have swallowed freshwater. It was concluded that this study design is suitable to study the relationship between health complaints and microbiological water quality. In the summers of 1993 and 1994, a study will be carried out concerning several run-bike-runs and triathlons in freshwaters of different quality.

Dry and storm weather transport of coliforms and faecal streptococci in combined sewage

1995 ◽  
Vol 31 (7) ◽  
pp. 311-320 ◽  
Author(s):  
R. M. Ashley ◽  
W. Dabrowski
Keyword(s):  
Data Collection ◽  
Coliform Bacteria ◽  
Pathogenic Microorganisms ◽  
Chemical Parameters ◽  
Physical Chemical ◽  
Sediment Bacteria ◽  
Wet Weather ◽  
Faecal Streptococci

Combined sewage coliform bacteria are important as indicators of pathogenic microorganisms and of their possible discharge into the environment. Whilst specifying limits for viruses, most legislation recognises the difficulty of enumerating such organisms and also prescribes limits for coliforms. Despite the importance of these organisms, little is known about their numbers and behaviour in sewerage systems. A data collection programme is described which has monitored dry and wet weather sewage coliform bacteria and also sediment bacteria. These data are used to review recent UK recommendations for assessing bacteria numbers in storm discharges. It is concluded that relationships between bacteria numbers and other physical/chemical parameters may be developed during DWF, but are seasonally and catchment dependent. Extension of DWF measurements to predict storm bacteria may be possible with more data.

UV ability to inactivate microorganisms combined with factors affecting radiation

1997 ◽  
Vol 35 (11-12) ◽  
pp. 107-112 ◽  
Author(s):  
A. M. Shaban ◽  
G. E. El-Taweel ◽  
G. H. Ali
Keyword(s):  
Microbial Communities ◽  
Uv Radiation ◽  
Contact Time ◽  
Tap Water ◽  
Scenedesmus Obliquus ◽  
Morphological Characters ◽  
The Other ◽  
Bacterial Cells ◽  
Dark Repair ◽  
Nile Water

In the present study, the effect of UV radiation on the inactivation of a range of microorganisms was studied. Each organism was seeded into sterile tap water and exposed to UV in batch experiments with changing turbidities. In addition, the effect of UV on microbial communities in river Nile water was examined. It was found that 1min contact time (0.5L/min flow rate) was effective against vegetative cells levels almost reaching zero (except with Staphylococcus aureus). On the other hand, spore-forming bacteria, Candida albicans and coliphage were more resistant to UV. This contact time caused coenobia cells in single form with Scenedesmus obliquus while for Microcystis aeruginosa colonies broke into smaller groups. Exposure of Nile water microbial communities to UV showed that yeasts and Aeromonas survived better than the other organisms while in the phytoplankton partial fragmentation occurred in some algal groups. The protective effect of turbidity differed between organisms, with increased contact time under conditions of stable turbidity having no effect on the organisms. At 20 NTU the UV radiation had no effect on the morphological characters of algal cells. In reactivation experiments, it is clear that photoreactivation, and not dark repair, takes place with bacterial cells. Only coliphage had no photoreactivation and dark repair responses although with coliphage and host, both reactivation processes worked well. Moreover, the irradiated algae regained their normal shape after 3 days in suitable media and enough light.

Evaluation of the disinfection potential of low chlorine concentrations in tap water using immobilised enterococcus faecium in a continuous flow device

1997 ◽  
Vol 35 (11-12) ◽  
pp. 77-80 ◽  
Author(s):  
A. Wiedenmann ◽  
M. Braun ◽  
K. Botzenhart
Keyword(s):  
Distribution System ◽  
Enterococcus Faecium ◽  
Continuous Flow ◽  
Tap Water ◽  
Test System ◽  
Batch Experiments ◽  
Membrane Filters ◽  
Upper Limit ◽  
Flow Device ◽  
Faecal Streptococci

A simple continuous flow device in which bacteria were immobilised on membrane filters and flushed with tap water with free chlorine residuals of 0.05, 0.1, 0.2 and 0.4mg/L at pH 7.7 and 10°C, has been used for disinfection experiments with faecal streptococci. A 99.99% reduction of Enterococcus faecium was observed between 3.4–5.2min (0.05mg/L), between 2.8–4.1min (0.1mg/L), between 1.7–3.1min (0.2mg/L) and between 0.8–2.1min (0.4mg/L). CT-products covered a range of 0.17 (0.05mg/L, lower limit) up to 0.85mg/L/min (0.4mg/L, upper limit). The test system is suggested as a more reliable alternative to batch experiments when the disinfection potential of low chlorine concentrations acting for several minutes has to be evaluated. The system cannot be used to demonstrate exact reduction kinetics but it allows the calculation of CT values and the evaluation of the disinfection potential of chlorinated water at any point of a distribution system where initial chlorine concentrations may have already remarkably declined.

scholarly journals Past and future trends of Egypt’s water consumption and its sources

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Catherine A. Nikiel ◽  
Elfatih A. B. Eltahir
Keyword(s):  
Economic Growth ◽  
Virtual Water ◽  
Comprehensive Analysis ◽  
Future Trends ◽  
Nile Water ◽  
The Gift ◽  
Per Capita ◽  
The 1960S

AbstractFor millennia the Nile supplied Egypt with more water than needed. As the population grew and the economy expanded, demand on water increased accordingly. Here, we present a comprehensive analysis to reconstruct how total demand on water outstripped supply of the Nile water in the late 1970s, starting from a surplus of about 20 km3 per year in the 1960s leading to a deficit of about 40 km3 per year by the late 2010s. The gap is satisfied by import of virtual water. The role of economic growth in driving per capita demand on water is quantified based on detailed analysis of water use by agriculture and other sectors. We develop and test an empirical model of water demand in Egypt that relates demand on water to growth rates in the economy and population. Looking forward, we project that within this decade of the 2020 s, under nominal scenarios of population and economic growth, Egypt is likely to import more virtual water than the water supplied by the Nile, bringing into question the historical characterization of Egypt as “the gift of the Nile”.

scholarly journals The quantitative bacteriology of some commercial bivalve shellfish entering British markets

1975 ◽  
Vol 74 (3) ◽  
pp. 431-440 ◽  
Author(s):  
P. A. Ayres
Keyword(s):  
Public Health ◽  
Escherichia Coli ◽  
Health Risk ◽  
E Coli ◽  
Accepted Standard ◽  
Plate Counts ◽  
Bivalve Shellfish ◽  
Faecal Streptococci ◽  
Specific Illness

SUMMARYIncidents of non-specific illness associated with the consumption of oysters have highlighted the lack of published information on the bacteriology of shellfish suitable for consumption. Investigations showed that the majority of molluscan shellfish entering English markets conform to the accepted standard of less than 5 Escherichia coli/ml. tissue. The numbers of E. coli were related to the sanitary quality of the growing area but no relation could be established between numbers of E. coli and coliforms, faecal streptococci or Clostridium welchii. The numbers of non-specific bacteria varied considerably but shellfish from sources associated with non-specific illness yielded relatively high counts at 37° C. The results showed that there was no justification for a standard based on total plate counts, which often exceeded 106/g. Such a standard would have to be coupled with spoilage or the incidence of non-specific illness. The relation between the numbers of non-specific bacteria growing at 20 and 37° C. appears to be a useful measure for assessing the likelihood that raw shellfish are a public health risk.

Relationship between Pseudomonas aeruginosa and Bacterial Indicators in Polluted Natural Waters

1991 ◽  
Vol 24 (2) ◽  
pp. 121-124 ◽  
Author(s):  
A. de Vicente ◽  
J. C. Codina ◽  
P. Romero
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Natural Waters ◽  
Pollution Index ◽  
Close Correlation ◽  
Aquatic Environments ◽  
Faecal Coliforms ◽  
Faecal Pollution ◽  
The Relationship ◽  
Faecal Indicators ◽  
Faecal Streptococci

The relationship between Pseudomonas aeruginosa and the faecal pollution index (total coliforms, faecal coliforms and faecal streptococci) in natural waters was established. Water samples were collected from several aquatic environments in Málaga (Spain). P. aeruginosa counts and isolation frequencies were clearly associated with the degree of faecal pollution of the studied water. The results confirmed that domestic sewage was the major source of P. aeruginosa in river and seawater, being isolated from sewage at concentrations about 105 cfu/100 ml. There was a close correlation between the P. aeruginosa concentration and the densities of the three faecal indicators in both river and marine waters. A significant correlation was not observed in waters with little faecal pollution because P. aeruginosa was only occasionally isolated from these waters and at very low densities. P. aeruginosa concentrations in sewage and polluted natural waters were generally 3-4 log lower than the TC densities and 2 log lower than FC and FS concentrations. TC, FC and FS could be considered adequate indicators of the presence and densities of P. aeruginosa in natural waters, especially TC in freshwaters and FS in seawater respectively, as these parameters showed the best correlations and the most parallel inactivation processes with P. aeruginosa in each environment.

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