scholarly journals Microbial Risks in Household UF Purifiers and Disinfection Strategy with Electrolysis

2020 ◽  
Vol 143 ◽  
pp. 02028
Author(s):  
Yucheng Chen ◽  
Jian-nan Fu ◽  
Yi Wang ◽  
Jian Ding ◽  
Xiaoying Lian ◽  
...  
Keyword(s):  
Drinking Water ◽  
Residence Time ◽  
Bacterial Growth ◽  
Microbial Contamination ◽  
Tap Water ◽  
Lag Phase ◽  
Pilot Test ◽  
Acceptable Range ◽  
Hygienic Standard ◽  
Microbial Risks

The research studied microbial deterioration in household ultrafiltration membrane (UF) purifiers with residence time and anti-bacterial strategy with electrolysis. The pilot test was conducted on a household drinking water purifier. A 72-h stagnation test and a 60-min anti-bacterial test with electrolysis were subsequently done. There were some findings in this study: (1) The level of HPC exceeded the hygienic standard when the stagnation time was more than 3 h. (2) The lag phase of bacterial growth was no more than 12 h in filters. (3) With the method of electrolysis, microbial contamination induced by water stagnation can be controlled in the acceptable range, which was more efficient than the method of flushing with tap water.

Effects of AOC and Phosphorus on Bacterial Growth under Oligotrophic Condition (1)

2011 ◽  
Vol 138-139 ◽  
pp. 981-987
Author(s):  
Deng Ling Jiang ◽  
Guo Wei Ni ◽  
Yu Min Zhang
Keyword(s):  
Drinking Water ◽  
Organic Carbon ◽  
Bacterial Growth ◽  
Water Samples ◽  
Phosphorus Concentration ◽  
Lag Phase ◽  
Limiting Factor ◽  
Bacterial Number ◽  
In The Beginning ◽  
Oligotrophic Condition

The effects of phosphorus and organic carbon on bacterial growth were investigated in the laboratory. The bacteria sampled from the drinking water network of Tianjin were inoculated into water samples with different content of phosphorus (0～15µg PO43--P/L) and assimilable organic carbon (10～200µgAOC/L). The inoculated water samples were incubated at 20°C. Bacterial growth was monitored in every 2 days in the beginning of cultivation and in every 4 days or more in the later of the cultivation. Results showed that Phosphorus had obvious promotion on bacterial growth, which included shortening the lag phase evidently, increasing the growth rate and the maximum cell count in stationary phase. Carbon can only increase bacterial number. Under oligotrophic condition，when ratio of AOC: P in nutrients of water was more than 100:5, phosphorus was the limiting factor of bacterial growth. The bacterial yield factors against phosphorus and AOC were 1.1×109CFU/µgP and 9.0×107CFU/µgAOC respectively. Phosphorus was more sensitive than AOC. When the phosphorus concentration was less than 0.7µg/L in water samples, it was very difficult for bacteria to obtain phosphorus, and then growth of bacteria was very slowly or in lag phase in the first nine days of incubation time. In drinking water with low concentration of phosphorus (<0.7µg/L) and disinfectants, bacterial regrowth may be controlled. The paper will be Narrated in two parts, “Effects of AOC and Phosphorus on Bacterial Growth under Oligotrophic Condition (1)” and “Effects of AOC and Phosphorus on Bacterial Growth under Oligotrophic Condition (2)”.

scholarly journals Treatment of water from different sources for safe drinking of rural poultry and livestock of Bangladesh

1970 ◽  
Vol 6 (1) ◽  
pp. 37-43 ◽  
Author(s):  
RP Ruma ◽  
MH Haque ◽  
MA Zinnah ◽  
MT Hossain ◽  
MT Islam ◽  
...  
Keyword(s):  
Drinking Water ◽  
Water Samples ◽  
Microbial Contamination ◽  
Tap Water ◽  
Safe Drinking Water ◽  
Bleaching Powder ◽  
Chemical Agents ◽  
Before And After ◽  
Different Sources ◽  
Rural Poultry

The research work was under taken to find out the effect of various treatments on water of different sources with a view to supply safe drinking water for rural poultry and livestock. For that, water of four different sources (lake, river, tap, tube well of BAU campus) were collected during the period from December 2006 to June 2007 and subjected to several treatments with physical (heat) and chemical (Hello tab, bleaching powder, potassium permanganate, alum and acetic acid) means in the Department of Microbiology and Hygiene, Bangladesh Agricultural University, Mymensingh-2202 with a view to get water free from deleterious microorganisms those are easily transmitted through drinking water of the above mentioned sources. Water of all the sources were subjected to microbiological examination before and after treatment. No bacteria was found in the water samples collected from tube well of five places of BAU campus following cultural examination. Gram positive rod shaped bacteria were isolated from the river and tap water of Ishakhan Hall Lake (IHL), Brahmaputra river (BR), Taposhi Rabeya Hall (TRH), Teacher staff quarter (TSQ), Microbiology laboratory (ML) and Bangabandhu Hall (BBH) whereas Gram negative rod shaped bacteria (E. coli) were isolated from the water of IHL, BR and from the tap water of ML and BBH. Gram positive cocci was found only in the tap water of ML. The pre-treatment culture of water samples revealed that the TVC (387 CFU/ml) and TCC (75 CFU/ml) were highest in the water of lake compare to those of other water samples collected from river and taps. As a physical means heat treatment (1000C for 4 to 8 minutes) was highly effective. No single colony was found in all the water samples following treatment with heat. No changes in colour, taste and odour were noticed before and after heat treatment of all the water samples. Among the chemical agents, Hello tab (0.05 g/100 ml) was found to be the most effective to make the water free from all the microbial contamination. The taste, colour and odour of the Hello tab treated water samples were found as normal as safe drinking water. The colour, taste and odour of water treated with bleaching powder, potassium permanganate, alum and acetic acid were also examined and it was found that the colour, taste and odour were not normal after treatment of the water samples. Therefore, it may be concluded that the water treated with Hello tab was found superior compare to the water of other treatments in this study which was found free from microbial contamination and unpleasant taste and order. Key words: Water, microorganisms, chemical agents, heat DOI = 10.3329/bjvm.v6i1.1337 Bangl. J. Vet. Med. (2008). 6 (1): 37-43

Effects of AOC and Phosphorus on Bacterial Growth under Oligotrophic Condition (2)

2011 ◽  
Vol 138-139 ◽  
pp. 988-994
Author(s):  
Deng Ling Jiang ◽  
Yu Min Zhang ◽  
Guo Wei Ni
Keyword(s):  
Drinking Water ◽  
Organic Carbon ◽  
Bacterial Growth ◽  
Water Samples ◽  
Phosphorus Concentration ◽  
Lag Phase ◽  
Limiting Factor ◽  
Bacterial Number ◽  
In The Beginning ◽  
Oligotrophic Condition

The effects of phosphorus and organic carbon on bacterial growth were investigated in the laboratory. The bacteria sampled from the drinking water network of Tianjin were inoculated into water samples with different content of phosphorus (0～15µg PO43--P/L) and assimilable organic carbon (10～200µgAOC/L). The inoculated water samples were incubated at 20°C. Bacterial growth was monitored in every 2 days in the beginning of cultivation and in every 4 days or more in the later of the cultivation. Results showed that Phosphorus had obvious promotion on bacterial growth, which included shortening the lag phase evidently, increasing the growth rate and the maximum cell count in stationary phase. Carbon can only increase bacterial number. Under oligotrophic condition，when ratio of AOC: P in nutrients of water was more than 100:5, phosphorus was the limiting factor of bacterial growth. The bacterial yield factors against phosphorus and AOC were 1.1×109CFU/µgP and 9.0×107CFU/µgAOC respectively. Phosphorus was more sensitive than AOC. When the phosphorus concentration was less than 0.7µg/L in water samples, it was very difficult for bacteria to obtain phosphorus, and then growth of bacteria was very slowly or in lag phase in the first nine days of incubation time. In drinking water with low concentration of phosphorus (<0.7µg/L) and disinfectants, bacterial regrowth may be controlled. The paper will be Narrated in two parts, “Effects of AOC and Phosphorus on Bacterial Growth under Oligotrophic Condition (1)” and “Effects of AOC and Phosphorus on Bacterial Growth under Oligotrophic Condition (2)”.

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.

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.

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