scholarly journals Tryptophan-like and humic-like fluorophores are extracellular in groundwater: implications as real-time faecal indicators

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
James P. R. Sorensen ◽  
Andrew F. Carr ◽  
Jacintha Nayebare ◽  
Djim M. L. Diongue ◽  
Abdoulaye Pouye ◽  
...  
Keyword(s):  
Natural Organic Matter ◽  
Urban Population ◽  
Indicator Bacteria ◽  
Bacterial Cells ◽  
Extracellular Material ◽  
Faecal Indicator Bacteria ◽  
Controlling Variables ◽  
Microbial Risks ◽  
Entire Dataset ◽  
Faecal Indicators

Abstract Fluorescent natural organic matter at tryptophan-like (TLF) and humic-like fluorescence (HLF) peaks is associated with the presence and enumeration of faecal indicator bacteria in groundwater. We hypothesise, however, that it is predominantly extracellular material that fluoresces at these wavelengths, not bacterial cells. We quantified total (unfiltered) and extracellular (filtered at < 0.22 µm) TLF and HLF in 140 groundwater sources across a range of urban population densities in Kenya, Malawi, Senegal, and Uganda. Where changes in fluorescence occurred following filtration they were correlated with potential controlling variables. A significant reduction in TLF following filtration (ΔTLF) was observed across the entire dataset, although the majority of the signal remained and thus considered extracellular (median 96.9%). ΔTLF was only significant in more urbanised study areas where TLF was greatest. Beneath Dakar, Senegal, ΔTLF was significantly correlated to total bacterial cells (ρs 0.51). No significant change in HLF following filtration across all data indicates these fluorophores are extracellular. Our results suggest that TLF and HLF are more mobile than faecal indicator bacteria and larger pathogens in groundwater, as the predominantly extracellular fluorophores are less prone to straining. Consequently, TLF/HLF are more precautionary indicators of microbial risks than faecal indicator bacteria in groundwater-derived drinking water.

scholarly journals Implications of faecal indicator bacteria for the microbiological assessment of roof-harvested rainwater quality in southeast Queensland, Australia

2010 ◽  
Vol 56 (6) ◽  
pp. 471-479 ◽  
Author(s):  
W. Ahmed ◽  
A. Goonetilleke ◽  
T. Gardner
Keyword(s):  
Clostridium Perfringens ◽  
Legionella Pneumophila ◽  
Microbiological Quality ◽  
Indicator Bacteria ◽  
Microbiological Analysis ◽  
Pathogenic Microorganisms ◽  
Faecal Indicator Bacteria ◽  
E Coli ◽  
Faecal Indicators

The study aimed to evaluate the suitability of Escherichia coli , enterococci, and Clostridium perfringens for assessing the microbiological quality of roof-harvested rainwater and assessing whether the concentrations of these faecal indicators can be used to predict the presence or absence of specific zoonotic bacterial or protozoan pathogens. From a total of 100 samples tested, 58%, 83%, and 46% of samples were found to be positive for, respectively, E. coli, enterococci, and Clostridium perfringens spores, as determined by traditional culture-based methods. Additionally, in the samples tested, 7%, 19%, 1%, 8%, 17%, and 15% were PCR positive for Aeromonas hydrophila lip, Campylobacter coli ceuE, Campylobacter jejuni mapA, Legionella pneumophila mip, Salmonella invA, and Giardia lamblia β-giardin genes, respectively. However, none of the samples was positive for E. coli O157 lipopolysaccharide, verocytotoxin 1, and verocytotoxin 2 and Cryptosporidium parvum oocyst wall protein genes. The presence or absence of these potential pathogens did not correlate with any of the faecal indicator bacterial concentrations as determined by a binary logistic regression model. The roof-harvested rainwater samples tested in this study appeared to be of poor microbiological quality, and no significant correlation was found between the concentration of faecal indicators and pathogenic microorganisms. The use of faecal indicator bacteria raises questions regarding their reliability in assessing the microbiological quality of water and particularly their poor correlation with pathogenic microorganisms. The presence of one or more zoonotic pathogens suggests that the microbiological analysis of water should be performed and that appropriate treatment measures should be undertaken, especially in tanks where the water is used for drinking.

scholarly journals Spatial and temporal variations of faecal indicator bacteria in Lake Bunyonyi, South-Western Uganda

2021 ◽  
Vol 3 (7) ◽  
Author(s):  
Alex Saturday ◽  
Thomas J. Lyimo ◽  
John Machiwa ◽  
Siajali Pamba
Keyword(s):  
Health Risks ◽  
Rank Correlation ◽  
Temporal Variations ◽  
Indicator Bacteria ◽  
Spatial And Temporal Variations ◽  
Wet Season ◽  
Recreational Waters ◽  
Faecal Indicator Bacteria ◽  
E Coli ◽  
Spearman’S Rank Correlation

AbstractBackground Microbial water quality serves to indicate health risks associated with the consumption of contaminated water. Nevertheless, little is known about the microbiological characteristics of water in Lake Bunyonyi. This study was therefore undertaken to examine the spatial and temporal variations of faecal indicator bacteria (FIB) in relation to physicochemical parameters in Lake Bunyonyi. Result The FIB concentration was consistently measured during sampling months and correlated with each other showing the presumed human faecal pollution in the lake. The highest concentration values for E. coli (64.7 ± 47.3 CFU/100 mL) and enterococci (24.6 ± 32.4 CFU/100 mL were obtained in the station close to the Mugyera trading centre. On a temporal basis, the maximum values were recorded during the rainy season in October 2019 (70.7 ± 56.5 CFU/100 mL for E. coli and 38.44 ± 31.8 CFU/100 mL for enterococci. FIB did not differ significantly among the study stations (p > 0.05) but showed significant temporal variations among the months (p < 0.05) with concentrations being significantly high in wet season than dry season (U = 794, p < 0.0001 for E. coli; U = 993.5, p = 0.008 for enterococci). Spearman’s rank correlation revealed that FIB concentrations were significantly positively correlated with turbidity and DO concentration levels (p < 0.05). Approximately 97.2% of the water samples had E. coli and enterococci concentrations levels below USEPA threshold for recreational waters. Likewise, 98.1 and 90.7% of samples recorded E. coli and enterococci counts exceeding the UNBS, APHA, WHO and EU threshold values for drinking water. Conclusion The FIB counts show that the Lake Bunyonyi water is bacteriologically unsuitable for drinking unless it is treated since the FIB pose health risks to consumers. Besides, the water can be used for recreational purposes.

scholarly journals Inactivation of faecal indicator bacteria in a roof-captured rainwater system under ambient meteorological conditions

2013 ◽  
Vol 116 (1) ◽  
pp. 199-207 ◽  
Author(s):  
W. Ahmed ◽  
K. Richardson ◽  
J.P.S. Sidhu ◽  
P. Jagals ◽  
S. Toze
Keyword(s):  
Meteorological Conditions ◽  
Indicator Bacteria ◽  
Faecal Indicator Bacteria

scholarly journals Pilot- and bench-scale testing of faecal indicator bacteria survival in marine beach sand near point sources

2009 ◽  
Vol 107 (1) ◽  
pp. 72-84 ◽  
Author(s):  
K.B. Mika ◽  
G. Imamura ◽  
C. Chang ◽  
V. Conway ◽  
G. Fernandez ◽  
...  
Keyword(s):  
Point Sources ◽  
Indicator Bacteria ◽  
Beach Sand ◽  
Faecal Indicator Bacteria ◽  
Bench Scale

Demonstration of an optical biosensor for the detection of faecal indicator bacteria in freshwater and coastal bathing areas

2019 ◽  
Vol 411 (29) ◽  
pp. 7637-7643
Author(s):  
Ciprian Briciu-Burghina ◽  
Brendan Heery ◽  
Gillian Duffy ◽  
Dermot Brabazon ◽  
Fiona Regan
Keyword(s):  
Optical Biosensor ◽  
Indicator Bacteria ◽  
Faecal Indicator Bacteria

Monitoring coastal marine waters for spore-forming bacteria of faecal and soil origin to determine point from non-point source pollution

2001 ◽  
Vol 44 (7) ◽  
pp. 181-181 ◽  
Author(s):  
R. S. Fujioka
Keyword(s):  
Water Quality ◽  
Point Source ◽  
Quality Standards ◽  
Indicator Bacteria ◽  
Recreational Water ◽  
Water Quality Standards ◽  
Point Source Pollution ◽  
Faecal Indicator Bacteria ◽  
Recreational Water Quality ◽  
Non Point Source Pollution

The US Environmental Protection Agency (USEPA) and the World Health Organization (WHO) have established recreational water quality standards limiting the concentrations of faecal indicator bacteria (faecal coliform, E. coli, enterococci) to ensure that these waters are safe for swimming. In the application of these hygienic water quality standards, it is assumed that there are no significant environmental sources of these faecal indicator bacteria which are unrelated to direct faecal contamination. However, we previously reported that these faecal indicator bacteria are able to grow in the soil environment of humid tropical island environments such as Hawaii and Guam and are transported at high concentrations into streams and storm drains by rain. Thus, streams and storm drains in Hawaii contain consistently high concentrations of faecal indicator bacteria which routinely exceed the EPA and WHO recreational water quality standards. Since, streams and storm drains eventually flow out to coastal marine waters, we hypothesize that all the coastal beaches which receive run-off from streams and storm drains will contain elevated concentrations of faecal indicator bacteria. To test this hypothesis, we monitored the coastal waters at four beaches known to receive water from stream or storm drains for salinity, turbidity, and used the two faecal indicator bacteria (E. coli, enterococci) to establish recreational water quality standards. To determine if these coastal waters are contaminated with non-point source pollution (streams) or with point source pollution (sewage effluent), these same water samples were also assayed for spore-forming bacteria of faecal origin (Cl. perfringens) and of soil origin (Bacillus species). Using this monitoring strategy it was possible to determine when coastal marine waters were contaminated with non-point source pollution and when coastal waters were contaminated with point source pollution. The results of this study are most likely applicable to all countries in the warm and humid region of the world.

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