Detection of enterococci with rRNA targeted DNA probes and their use for hygienic drinking water control

1997 ◽  
Vol 35 (11-12) ◽  
pp. 437-444 ◽  
Author(s):  
H. Meier ◽  
C. Koob ◽  
W. Ludwig ◽  
R. Amann ◽  
E. Frahm ◽  
...  
Keyword(s):  
Drinking Water ◽  
Fluorescent Dyes ◽  
Tap Water ◽  
High Sensitivity ◽  
Epifluorescence Microscopy ◽  
Quantitative Detection ◽  
Dot Blot ◽  
Water Control ◽  
Accurate Identification ◽  
Faecal Contamination

Enterococci are useful indicators of faecal contamination with their high abundance in faeces and long survival in the environment and the possibility of indicating the source of contamination by species identification has lead to discussion of whether enterococci would be more reliable faecal indicators than E. coli. In an attempt to facilitate rapid and accurate identification of enterococci, 16S rRNA targeted oligonucleotide probes were designed by computer-aided analysis of more than 4,000 rRNA sequences. Probes were labelled non-isotopically with digoxigenin and fluorescent dyes. Conditions for specific hybridisation were optimised for dot blot hybridisation and whole cell hybridisation for all probes. With a combination of two probes, all hygienically important enterococci could be detected and 24 biochemically identified environmental isolates also hybridised with one of these probes. A quantitative detection method with a high sensitivity was developed based on filtration of water samples through polycarbonate filters, a short incubation on agar and microcolony filter hybridisation with fluorescently labelled probes followed by epifluorescence microscopy. Within 8–20h sampling a specific identification of enterococcal microcolonies was possible. With this method 15/32 well- and tap-water sources from the Mainz area were identified as being of substandard quality. The proposed method detects faecal contamination significantly earlier than conventional methods and could be helpful in the hygienic monitoring of drinking water.

scholarly journals Faecal contamination of drinking water in a Brazilian shanty town: importance of household storage and new human faecal marker testing

2009 ◽  
Vol 7 (2) ◽  
pp. 324-331 ◽  
Author(s):  
Curtis C. Copeland ◽  
Benjamin B. Beers ◽  
Meghan R. Thompson ◽  
Relana P. Fitzgerald ◽  
Leah J. Barrett ◽  
...  
Keyword(s):  
Drinking Water ◽  
Disease Burden ◽  
Tap Water ◽  
Faecal Contamination ◽  
North East ◽  
Enteric Infections ◽  
Shanty Town ◽  
Contaminated Drinking Water ◽  
Relative Potential ◽  
And Storage

Worldwide, contaminated drinking water poses a major health threat, particularly to child development. Diarrhoea represents a large part of the water-related disease burden and enteric infections have been linked to nutritional and growth shortfalls as well as long-term physical and cognitive impairment in children. Previous studies detailed the frequency of infection and the consequences for child health in a shanty town in north-east Brazil. To determine the frequency of contaminated water, we measured faecal contamination in primary drinking water samples from 231 randomly selected households. Risk for contamination was compared across source and storage types. Nearly a third of the study households (70/231: 30.3%) had contaminated drinking water; the source with the highest frequency of contamination was well water (23/24: 95.8%). For tap water, the type of storage had a significant effect on the susceptibility to contamination (χ2=12.090; p=0.007). The observed pattern of contamination demonstrated the relative potential contributions of both source and storage. With evidence that supports the inclusion of source and storage in water quality surveys, this study, like others, suggests that contaminated drinking water in storage vessels may be an important factor for the documented diarrhoea disease burden in the Brazilian shanty town.

Relationship between availability of basic amenities and proportion of Slum population in Maharashtra

2020 ◽  
Vol 6 (11) ◽  
pp. 1343-1354
Author(s):  
Dr. Sakreen Hasan
Keyword(s):  
Drinking Water ◽  
Tap Water ◽  
Policy Implications ◽  
Class I ◽  
Urban Centers ◽  
The Sustainable Development ◽  
Closed Drainage ◽  
The People ◽  
Basic Infrastructure ◽  
Slum Population

The urban centers offering diverse employment opportunities and means of livelihood are the main centers of attraction for migration. But the availability of infrastructure is low to accommodate the invariably growing population. The access to basic amenities like electricity, drinking water, toilet facility, wastewater outlet and clean fuel are critical determinants of quality of urbanization. And if it lacks, then it would facilitates the growth of slum.  In this paper it being tried to capture the interdependent relationship between basic amenities and slum population residing in the class I towns in Maharashtra; largest slum populated state of India. As the slum is all about the situation or condition in which the people of medium and lower strata are living. A detailed analysis of proportion of slum population and availability of amenities which includes good housing condition, treated tap water as the source of drinking water, electricity as the source of lightning, households having latrine and bathing facility within the premises, waste water outlet connected to closed drainage, and households availing the banking facilities. This may be a limitation of the study that only these indicators have been taken to assess the availability of amenities and to calculate the amenity index of class I towns of the state of Maharashtra. To achieve the sustainable development goal (Sustainable cities and communities), we have to control the growth of slum population and to combat the formation of slum; we have to analyze the situation of basic infrastructure provided in urban centers. Amenities and slum population has policy implications as to reduce the slum population, provide basic amenities to the households which will improve their standard of living and ultimately lead to reduction in growth of slum and check the future slum formation.

ECOLOGICAL AND PHYSIOLOGICAL ASSESSMENT OF CHEMICAL COMPOSITION OF DRINKING TAP WATER IN KHANTY-MANSIYSK AND SALEKHARD

2020 ◽  
pp. 159-167
Author(s):  
V.V. Lapenko ◽  
L.N. Bikbulatova ◽  
E.M. Ternikova
Keyword(s):  
Drinking Water ◽  
Chemical Composition ◽  
Water Samples ◽  
Tap Water ◽  
Iron Concentration ◽  
Absorption Spectrometry ◽  
Northern Region ◽  
Transport Processes ◽  
Magnesium Concentration ◽  
Geochemical Environment

Water is very important for humans, as it is a solvent for metabolic products. Moreover, it is necessary for metabolism, biochemical and transport processes. The elemental status in persons depends on the geochemical environment and consumption of bioelements with food and water. The aim of the paper is to conduct a comprehensive assessment of chemical composition of drinking tap water in Khanty-Mansiysk and Salekhard. Materials and Methods. The chemical composition of 100 samples of drinking tap water was analyzed by atomic absorption spectrometry, spectrophotometry and capillary electrophoresis. All in all, there were 50 samples from Khanty-Mansiysk and 50 samples from Salekhard. The results were compared with Sanitary Rules and Norms 2.1.4.1074-01. Results. Drinking tap water in Salekhard contains a significantly higher concentration of iron, which is much above the maximum allowable concentration, if compared to water samples in Khanty-Mansiysk (p=0.03). In the cities under consideration, the water undergoes high-quality reagent-free treatment. However, the deterioration of the water supply networks in Salekhard is 3 times as high as in Khanty-Mansiysk. Calcium and magnesium concentration in water samples from Khanty-Mansiysk is 5.6 and 3.9 times lower than the MAC; in water samples from Salekhard calcium concentration is 6.3 (p=0.008) and magnesium concentration 4.6 (p<0.001) times lower than the MAC. Conclusion. The consumption of ultra-fresh drinking water leads to low intake of bioelements, which are a part of enzymes contributing to the human antioxidant defense and can result in manifestation of cardiovascular diseases. This is especially true for Salekhard with very soft drinking water and high iron concentration, which excess can exhibit prooxidant properties. Keywords: tap water, bioelements, northern region, antioxidants. Вода является важнейшим соединением для человека: необходима в качестве растворителя продуктов метаболизма и протекания обменных, биохимических и транспортных процессов. Элементный статус организма человека зависит от геохимического окружения и поступления биоэлементов с пищей и водой. Цель. Провести комплексную оценку химического состава водопроводной воды городов Ханты-Мансийск и Салехард. Материалы и методы. Методами атомно-абсорбционной спектрометрии, спектрофотометрии и капиллярного электрофореза проанализирован химический состав 100 проб водопроводной воды: по 50 из Ханты-Мансийска и Салехарда. Результаты сравнивали с СанПиН 2.1.4.1074-01. Результаты. В водопроводной воде Салехарда установлена превышающая ПДК и достоверно более высокая концентрация железа сравнительно с водой Ханты-Мансийска (р=0,03). При условии качественной безреагентной водоподготовки в изучаемых городах это обусловлено изношенностью водопроводных сетей в Салехарде, более чем в 3 раза превышающей этот показатель в Ханты-Мансийске. Концентрация кальция и магния в воде Ханты-Мансийска в 5,6 и 3,9 раза ниже ПДК; в воде Салехарда – в 6,3 (р=0,008) и 4,6 (р<0,001) раза ниже ПДК соответственно. Заключение. Употребление ультрапресной питьевой воды на фоне очень малого поступления с водой биоэлементов, входящих в состав ферментов антиоксидантной защиты организма человека, может привести к манифестации кардиоваскулярных заболеваний. Это особенно актуально для г. Салехарда с очень мягкой питьевой водой с повышенным содержанием железа, избыток которого может проявлять прооксидантные свойства. Ключевые слова: водопроводная вода, биоэлементы, северный регион, антиоксиданты.

Enterovirus Concentration Using Automated Hollow Fiber Ultrafiltration

1982 ◽  
Vol 14 (4-5) ◽  
pp. 257-272 ◽  
Author(s):  
G Belfort ◽  
A Paluszek ◽  
L S Sturman
Keyword(s):  
Drinking Water ◽  
Hollow Fiber ◽  
Enhanced Recovery ◽  
Tap Water ◽  
Membrane Surface ◽  
Creeping Flow ◽  
Hollow Fibers ◽  
Virus Concentration ◽  
Concentration Technique ◽  
Solution Interface

The Automated Hollow Fiber Ultrafiltration (AHFU) method is proposed here as a simple, efficient and rapid virus concentration technique from tap and drinking water sources. The results reported here extend the testing of the AHFU method to include two Picornaviruses [Poliovirus 2 (vaccine) and Echovirus 1] and Reovirus 3. Their respective mean virus recoveries from between 3 and 100 l of tap water is 88 ± 26, 79 ± 60, and 104 ± 48%. Various approaches including membrane surface modification, changes in backwash hydrodynamics, modification of the feed and backwash composition, and the use of S35-methionine labelled Poliovirus 2, are used to study the recovery of sorbed Poliovirus 2 from the hollow fiber/solution interface. An increase in the backwash pH to between 9.5 and 10.5 significantly improved Poliovirus 2 recovery. This, together with the labelled experiments, indicates that the virus-membrane interactions are probably electrostatic in nature. Convective polarization during filtration probably brings the virus close enough to the surface for these interactions to occur since virus losses were not detected for a non-permeation recycle experiment. Because very low Reynold's numbers are used, the flow is in the creeping-flow-regime for both filtration and backwashing (axial and radial). Unless significantly higher Reynolds could be used, enhanced recovery due to purely hydrodynamic forces is unlikely. High Reynold's numbers, of course, are limited by the pressure constraints of the hollow fibers.

H2S papers as presumptive tests for Salmonella contamination in tropical drinking water

1996 ◽  
Vol 34 (7-8) ◽  
pp. 187-194 ◽  
Author(s):  
Tanya Gawthorne ◽  
Robyn A. Gibbs ◽  
Kuruvilla Mathew ◽  
Goen E. Ho
Keyword(s):  
Drinking Water ◽  
Hydrogen Sulphide ◽  
Incubation Temperature ◽  
Indicator Bacteria ◽  
Coliform Bacteria ◽  
Salmonella Spp ◽  
Faecal Contamination ◽  
Tropical Waters ◽  
Remote Areas ◽  
Traditional Indicator

Coliform bacteria may not be adequate as sole indicators of recent faecal contamination in tropical waters. Salmonella spp. in particular have been found in tropical waters in the absence of traditional indicator bacteria. Remote areas without access to a laboratory have no opportunity for salmonellae analysis as portable tests are currently not available. H2S papers indicate the presence of hydrogen sulphide producing bacteria, a characteristic shared by the majority of Salmonella spp.. The potential of H2S papers to act as a presumptive test for salmonellae in the absence of coliform bacteria was assessed. Salmonella spp. grew in the H2S medium, with an optimum incubation temperature of 37°C and a recommended length of incubation for a negative result of 48 hours. The presence of high numbers of the type of noncoliform bacteria commonly found in drinking water did not affect the performance of the H2S strips. H2S papers are recommended for use in conjunction with a coliform test as a presumptive test for the presence of Salmonella spp. in drinking water.

Rapid, highly sensitive and quantitative detection of interleukin 6 based on SERS magnetic immunoassay

2021 ◽  
Vol 13 (15) ◽  
pp. 1823-1831
Author(s):  
Xiaomei Wang ◽  
Li Ma ◽  
Shijiao Sun ◽  
Tingwei Liu ◽  
Hao Zhou ◽  
...  
Keyword(s):  
Interleukin 6 ◽  
High Sensitivity ◽  
Quantitative Detection ◽  
Detection Time ◽  
Highly Sensitive ◽  
Sandwich Method

We have developed a SERS magnetic immunoassay method based on the principle of sandwich method for rapid and quantitative detection of IL-6. The developed SERS method has the advantages of high sensitivity and detection time is only 15 min.

scholarly journals How Perceptions of Trust, Risk, Tap Water Quality, and Salience Characterize Drinking Water Choices

Hydrology ◽  
2021 ◽  
Vol 8 (1) ◽  
pp. 49
Author(s):  
Madeline A. Grupper ◽  
Madeline E. Schreiber ◽  
Michael G. Sorice
Keyword(s):  
Water Quality ◽  
Drinking Water ◽  
Risk Perceptions ◽  
Anthropogenic Impacts ◽  
Tap Water ◽  
Water Utilities ◽  
Global Changes ◽  
Water Utility ◽  
The Public ◽  
Water Behavior

Provision of safe drinking water by water utilities is challenged by disturbances to water quality that have become increasingly frequent due to global changes and anthropogenic impacts. Many water utilities are turning to adaptable and flexible strategies to allow for resilient management of drinking water supplies. The success of resilience-based management depends on, and is enabled by, positive relationships with the public. To understand how relationships between managers and communities spill over to in-home drinking water behavior, we examined the role of trust, risk perceptions, salience of drinking water, and water quality evaluations in the choice of in-home drinking water sources for a population in Roanoke Virginia. Using survey data, our study characterized patterns of in-home drinking water behavior and explored related perceptions to determine if residents’ perceptions of their water and the municipal water utility could be intuited from this behavior. We characterized drinking water behavior using a hierarchical cluster analysis and highlighted the importance of studying a range of drinking water patterns. Through analyses of variance, we found that people who drink more tap water have higher trust in their water managers, evaluate water quality more favorably, have lower risk perceptions, and pay less attention to changes in their tap water. Utility managers may gauge information about aspects of their relationships with communities by examining drinking water behavior, which can be used to inform their future interactions with the public, with the goal of increasing resilience and adaptability to external water supply threats.

scholarly journals Faecal contamination of drinking water during collection and household storage: the need to extend protection to the point of use

2003 ◽  
Vol 1 (3) ◽  
pp. 109-115 ◽  
Author(s):  
Thomas F. Clasen ◽  
Andrew Bastable
Keyword(s):  
Drinking Water ◽  
Geometric Mean ◽  
Arithmetic Mean ◽  
Faecal Contamination ◽  
Household Level ◽  
Safe Water ◽  
Female Head ◽  
Point Of Use ◽  
Thermotolerant Coliforms ◽  
And Storage

Paired water samples were collected and analysed for thermotolerant coliforms (TTC) from 20 sources (17 developed or rehabilitated by Oxfam and 3 others) and from the stored household water supplies of 100 households (5 from each source) in 13 towns and villages in the Kailahun District of Sierra Leone. In addition, the female head of the 85 households drawing water from Oxfam improved sources was interviewed and information recorded on demographics, hygiene instruction and practices, sanitation facilities and water collection and storage practices. At the non-improved sources, the arithmetic mean TTC load was 407/100 ml at the point of distribution, rising to a mean count of 882/100 ml at the household level. Water from the improved sources met WHO guidelines, with no faecal contamination. At the household level, however, even this safe water was subject to frequent and extensive faecal contamination; 92.9% of stored household samples contained some level of TTC, 76.5% contained more than the 10 TTC per 100 ml threshold set by the Sphere Project for emergency conditions. The arithmetic mean TTC count for all samples from the sampled households was 244 TTC per 100 ml (geometric mean was 77). These results are consistent with other studies that demonstrate substantial levels of faecal contamination of even safe water during collection, storage and access in the home. They point to the need to extend drinking water quality beyond the point of distribution to the point of consumption. The options for such extended protection, including improved collection and storage methods and household-based water treatment, are discussed.

scholarly journals In-situ tryptophan-like fluorescence: A real-time indicator of faecal contamination in drinking water supplies

2015 ◽  
Vol 81 ◽  
pp. 38-46 ◽  
Author(s):  
J.P.R. Sorensen ◽  
D.J. Lapworth ◽  
B.P. Marchant ◽  
D.C.W. Nkhuwa ◽  
S. Pedley ◽  
...  
Keyword(s):  
Drinking Water ◽  
Real Time ◽  
Water Supplies ◽  
Faecal Contamination
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