scholarly journals Investigation of Microbiological Quality Changes of Roof-Harvested Rainwater Stored in the Tanks

Resources ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 103
Author(s):  
Monika Zdeb ◽  
Justyna Zamorska ◽  
Dorota Papciak ◽  
Agata Skwarczyńska-Wojsa

Rainwater has been found to be a valuable source of drinking water in Europe, especially in such crisis situations as those caused by contamination of water uptake into water supply systems, large-scale floods or terrorist attacks (e.g., biological weapons). The microbiological quality of water plays a significant role, which is directly related to the potential health risks associated with harvested rainwater (including rainwater stored in the tanks). Microbial contamination is commonly found in rainwater. However, in the literature, detailed results of qualitative and quantitative microbiological assessments are sparse and remain unexplored. Therefore, the aim of this study was to investigate and analyze changes in the microbiological quality of roof-harvested rainwater stored in the tanks, depending on the collection conditions (type of roof surface), storage duration and season. Authors elucidate that conditions such as storage duration, the season in which rainwater is collected, the roof-like surface types and morphology of the catchment area highly affect rainwater quality. This study showed that rainwater harvested from a galvanized steel sheet roof had the best microbial quality, regarding the lowest number of bacteria, while rainwater from a flat roof covered with epoxy resin was the worst. Further, it was detected that rainwater collected in autumn and spring obtained the best microbiological quality. Moreover, a decrease in the number of bacteria was observed in correlation to storage duration. The water became sanitary safe after six weeks of storage at 12 °C. Its use for purposes requiring drinking water quality before six weeks of storage required disinfection.

Author(s):  
Ngouakam H ◽  
◽  
Fru Cho J ◽  
Tientche B ◽  
◽  
...  

Background: The study aimed at assessing the knowledge of Bonendale populations related to safe drinking water; determine the microbiological quality and the household treatment practices of drinking water at the point of use (PoU). Methods: The study was descriptive and cross-sectional, conducted between November 2017 and November 2018 in Bonendale, Douala IV. A systematic random sampling method was used to select 237 households. Results: The main source of drinking water in the study population was dug wells (64.9%). The major activity around the boreholes was agriculture 50% (6/12) while agriculture and livestock rearing were practiced around 34.3% (12/35) and 42.8% (15/35) of dug wells respectively. Nearly half 110 (46.4%) of respondents had a good knowledge of physical properties of drinking water. Fifty-nine water samples out of a total of 60 tested (98.3%) were contaminated by coliform bacteria. Analysis of water samples indicated that 47.6% (10/21) of dug wells, 37.0% (10/27) of Camwater, and 41.2% (5/12) of boreholes had a total coliform count varying between 101-1000 CFU/100mL. And only a single Camwater water sample 1 (137%) had a coliform count of 0 CFU/100mL. Conclusion: These findings indicated the poor microbiological quality of point water used by Bonendale populations representing an important potential health risk of water-borne diseases. The results also reveal that a very high proportion of households treat their PoU before drinking.


1995 ◽  
Vol 31 (5-6) ◽  
pp. 75-79 ◽  
Author(s):  
M. Würzer ◽  
A. Wiedenmann ◽  
K. Botzenhart

In Germany the application of procedures such as flocculation and filtration in the preparation of drinking water results in the annual production of an estimated 500,000 t of sediments and sludges. Some of these residues have a potential for being reused, for example in agriculture, forestry, brickworks or waste water treatment. To assess the microbiological quality of residues from waterworks methods for the detection of enterobacteria, Escherichia coli, Salmonella, Pseudomonas aeruginosa, Legionella, poliovirus, Ascaris suis eggs and Cryptosporidium have been evaluated regarding their detection limits and were applied to various residues from German waterworks. Results show that sediments and sludges may contain pathogenic bacteria, viruses and protista. When residues from waterworks are intended to be reused in agriculture or forestry the microbiological quality should therefore be considered.


2008 ◽  
Vol 6 (S1) ◽  
pp. 21-26 ◽  
Author(s):  
John Gray

Water supply companies in the UK have a duty under prime UK legislation to notify the Drinking Water Inspectorate of events affecting or potentially affecting the quality of drinking-water supplies. Under the same legislation, the Inspectorate has a duty to investigate each event. After assessing all of the information available, including companies' reports, the Inspectorate advises on the way in which the event was handled and whether any statutory requirements were contravened. If appropriate, a prosecution of the water company may be initiated. Copies of the assessment are sent to the water company, relevant local and health authorities, Ofwat (the economic regulator), the regional Consumer Council for Water and any other interested parties, including consumers who request it. Generic guidance may be issued to the industry on matters of wider concern. This paper considers the role of the Inspectorate, the powers available to it and reporting arrangements. An overview is presented of events that occurred between 1990 and 2005 and common features are identified. Causes of different types of event are discussed. The importance of well-established contacts between the various interested parties involved in protecting public health is emphasised through discussion of example incidents.


2006 ◽  
Vol 53 (6) ◽  
pp. 75-82
Author(s):  
S. Lee ◽  
D. Cha ◽  
H. Park

In developing countries, the PPP (Public–Private–Partnerships) programs have been unsatisfied during the last decade. This study analyzed one of the main causes is low quality of the system. That is, no matter what supports developing countries may get through PPP, reforming water systems can be hardly successful without appropriate system quality. With this background, this study introduces service standards of ISO/TC 224 as an option to improve system quality of developing countries. To analyze its effects, system dynamic modeling was conducted. The results indicated that service standards, working with the PPP programs, can benefit all the stakeholders involved in the water systems in developing countries. Also this indicates further that this approach with service standards deserves more detailed study for improving the ailing water systems in developing countries.


2020 ◽  
Vol 14 (1) ◽  
pp. 78-83
Author(s):  
Ali Shahryari ◽  
Charlotte D. Smith ◽  
Abolfazl Amini

Background: The consumption of bottled water globally, including Iran, has increased tremendously in recent years. This study was designed to assess the bacteriological quality of bottled water and its compliance with the drinking water regulations. In addition, we evaluated bottled waters for the presence of a variety of genera of bacteria and the effect of storage duration on the extent of bacterial contamination. Methods: Four hundred samples of bottled water belonging to ten different Iranian brands with various production dates were purchased from supermarkets in Gorgan, Iran, from 2017 to 2018. Bacterial quality of bottled water was assessed using heterotrophic plate count (HPC) followed by usual biochemical tests for identification of bacterial genera, and by the API system. Results: The average HPC of bottled water was 9974 colony-forming units per milliliter (CFU/ml). Twelve genera were isolated, among which Bacillus spp. and Escherichia coli were the most and least abundant, respectively. Statistical analysis showed that there was a positive association between water quality and storage duration so that the highest microbial load occurred within the first to third months after bottling. Furthermore, the highest rate of contamination was observed in May when ambient air temperatures commonly reached 40 °C. Conclusion: The bacterial quality of bottled water was not according to the standard of drinking water quality. This study demonstrated the variation in bacterial levels after bottling, which indicates the presence of waterborne heterotrophic bacteria, some of which can pose severe health risks to consumers.


Foods ◽  
2020 ◽  
Vol 9 (6) ◽  
pp. 741
Author(s):  
Muhamad Faris Ab Aziz ◽  
Muhammad Nizam Hayat ◽  
Ubedullah Kaka ◽  
Nitty Hirawaty Kamarulzaman ◽  
Awis Qurni Sazili

Storage temperature and duration plays an important role in meat processing. Observations in poultry processing plants have shown a serious deviation in storage condition compared to the recommended procedures. Furthermore, there is still a paucity of evidence on the effects of storage temperature and duration on meat quality and microbial population. The aim of this study was to determine the effects of different temperature and duration during storage on physico-chemical properties and microbiological quality of broiler chicken Pectoralis major muscle. Eighty birds were slaughtered and processed, following which the packed boneless breast (PBB) (each bird was to provide two breast muscle samples; left breast and right breast) was divided into four groups, each consisted of 40 PBB. Each group was subsequently assigned to storage either at 4 °C, −10 °C, −18 °C or −40 °C, for 24 h before 20 PBB samples from each group were transported to the respective laboratory for meat quality and microbiological analysis. The remaining 20 PBB from each storage temperature were stored for 72 h before being transported for analysis. Results have shown significant increases in drip loss and cooking loss as the storage temperature decreases. Similarly, storage duration significantly affected cooking loss, of which, samples stored for 72 h exhibited higher cooking loss compared to those stored for 24 h. For color, significant differences were only observed in lightness (L*) and redness (a*) values. Longer duration of storage had significantly improved tenderness whereby, samples that have been stored for a shorter duration presented higher pH values. Populations of coliform and Salmonella decreased significantly with decreasing temperature and increasing storage duration.


2020 ◽  
Vol 841 ◽  
pp. 36-40
Author(s):  
Mardan Jalilov ◽  
Ayten Jalilova ◽  
Gulnar Feyziyeva ◽  
Makhanim Azimova

Given that the quality of water supplied to hot water supply systems must meet drinking water requirements, it is also important that the water preparation process is of great importance. The quality of that water is also important in terms of preventing the formation of heat in hot water systems. It is known that the main cause of the formation of water is the presence of calcium and magnesium cations and bicarbonate and sulfate anions in water. The traditional methods for preventing the limescale include the combination of calcium and magnesium cations from the water and replacing them with cations that are not easy to resolve at high temperatures. The quality of water treated by these methods does not meet drinking water requirements. Taking these into account, the Cl-anionizationprocess of drinking water has been developed in high-tech anionite technology. According to this technology, the first water from the city water gridis processed through anionite and activated carbon filters, which are mechanically charged with high anionite. The treated water is then cleaned out of microbes and bacteria through the ultraviolet disinfection equipment and delivered to the operator according to the quality requirements for drinking water. In the chlorine-anionization process, most of the sulfate and bicarbonate anions in water change to chlorine anions and their solidity remains constant. Thus, the density of the limescale-forming anions in the water decreases sharply and it meets the quality indicators of drinking water. High-grade anionite in the filter (8÷12) is regenerated by NaCl solution. The filtration rate of the solution from the anionite is determined depending on the concentration of calcium cations contained in the salt given for regeneration. Regeneration mode is such that the CaCO3 combination does not crumble when the anionite layer is formed. It is known that the temperature of the heated water in the hot water supply system does not exceed (60÷70)°C. In this case, the decomposition of limescale at Hc<2 mg-eq/l (carbonate hardness) is not observed. As carbonate hardness increases to 4 mg/l, the thin layer in the system shows a collapse. The basic element of the proposed technological schemeCl-anionite filter was applied at ADA University in Baku and positive results were obtained. Early observed collapse of pipes has been prevented and the working regime of hot water heaters has improved. A high-performance anionite such as A200EMBCl, which is a major ingredient of the UK's Purelite, and then the Russian-made AB-17-8 high-anionite anions have been used on the device.


2020 ◽  
Vol 8 (1) ◽  
pp. 27
Author(s):  
Nguepidjo Gilbert ◽  
Kapso Tchouankep Mireille ◽  
Ngong Ankiambom Innocent ◽  
Tonmeu Douyong Chimène Sandrine ◽  
Enoka Patrice ◽  
...  

Water is the basic drink for human beings and drinking water in sachets is very popular because of its relatively low cost and availability. The aim of this study is to determine the bacteriological profile of sachet drinking water sold in the city of Yaounde. It was a descriptive cross-sectional study covering the period from March to June 2019, carried out in the application laboratory of ETMS-Yaounde. A total of 230 samples of drinking water in sachets purchased in different markets in the city of Yaounde were analyzed using Mac Conkey's flooding method. The identification was done on the API 20 E Gallery and the susceptibility test on Mueller Hinton media. The size of the sample was 230 packaged sachet drinking water and 213 of the 230 revealed 92% of positive culture of germs, and only 17 samples gave a negative culture, at a percentage of 8% of isolated germs. The isolated bacterial species and their respective abundances in samples were Enterobacter gergoviae (3%), Klebsiella pneumoniae (5%), Proteus mirabilis (5%), Serratia fonticola (5%), Salmonella choler arizonae cloacae (8%), Salmonella spp. (8%), Enterobacter cloacae (10%), Staphylococcus aureus (10%), Pseudomonas aeruginosa (18%) and Staphylococcus epidermidis (28%). All these tested germs were resistant to Amoxicillin and Erythromycin and 70% of tested germs were sensitive to Gentamycin. Overall, the results revealed poor microbiological quality of these waters. This exposes consumers to health risks, and it is important to inform and sensitize consumers about the risks involved, to educate producers and to control their activities by the health services.


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