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Public perception of drinking water from private water supplies: focus group analyses
Andria Q Jones, Catherine E Dewey, Kathryn Doré, Shannon E Majowicz, Scott A McEwen, David Waltner-Toews, Spencer J Henson, Eric Mathews
BMC Public Health , 2005, DOI: 10.1186/1471-2458-5-129
Abstract: In September 2003, three focus group discussions were conducted; two with men and women aged 36–65 years, and one with men and women 20–35 years of age.Overall, participants had positive perceptions of their private water supplies, particularly in the older age group. Concerns included bacterial and chemical contamination from agricultural sources. Testing of water from private supplies was minimal and was done less frequently than recommended by the provincial government. Barriers to water testing included the inconvenience of the testing process, acceptable test results in the past, resident complacency and lack of knowledge. The younger participants greatly emphasized their need for more information on private water supplies. Participants from all groups wanted more information on water testing, and various media for information dissemination were discussed.While most participants were confident in the safety of their private water supply, the factual basis for these opinions is uncertain. Improved dissemination of information pertaining to private water supplies in this population is needed. Observed differences in the concerns expressed by users of different water systems and age groups may suggest the need for targeted public education strategies. These focus groups provided significant insight into the public perception of private water supplies and the need for public health outreach activities; however, to obtain a more representative understanding of the perceptions in this population, it is important that a larger scale investigation be performed.Over four million Canadians receive their drinking water from private water supplies, predominantly from groundwater wells [1]. Numerous studies report that Canadian private water supplies often exceed the minimal acceptable standards for microbial and chemical contamination [1-5], and it is estimated that 45 percent of all waterborne disease outbreaks in Canada involve non-municipal systems, largely in rural or
Quality Assessment of Egyptian Drinking Water Supplies and Disinfecting Using Ultraviolet Radiation  [PDF]
H.Abdel Karem,A.A.Hassan
Pakistan Journal of Biological Sciences , 2000,
Abstract: Drinking water, surface and underground water were microbiological and chemical analyzed during storage in covered and uncovered tanks for four months. Microbiological analyses were carried out to determine the microbial indicators namely, Total bacterial counts, total coliform, E.coli, Enterococcus faecalis, Pseudomonas aeruginosa and Clostridium perfringens. Drinking water of Amiria municipal water station was microbiologically safe after storage in covered tanks however, in uncovered tanks the total bacterial counts increased gradually to reach 8 x 102 cfu/ml at the fourth month.With respect to underground water, all tested groups of microorganisms were attained high values except E.coli and E.faecalis counts were not detected. During storage the densities of total bacterial counts, total coliform and P.aeruginosa increased in both covered and uncovered tanks to reach at the fourth month 106-107, 58-68, 51-65 cfu/ml respectively. As to bottled water, samples of four companies producing it in Egypt were taken for analysis during the steps of production. Companies A, B and C were used underground water and company D used surface water. Results revealed that all companies were microbiologically unsastifactory where final product still contained total bacterial counts, P.aeruginosa and C.perfringens exceeding the drinking water quality guideline values. An experiment was conducted to study the efficiency of uv radiation in reducing the densities of certain bacterial isolates inoculated in sterilized tap water. P.aeruginosa was the most sensitive bacteria followed by E.coli whereas E.faecalis and B.cereus were more resistant toward uv radiation.
Extent of Pollution Assessment in Drinking Water Supplies of Narayanganj District in Bangladesh
Bikash C. Sarker,M.W. Zaman
Journal of Biological Sciences , 2003,
Abstract: This study examined the chemical quality and suitability of 27 water samples of Narayanganj municipal area in Bangladesh for drinking purposes. The pH, electrical conductivity (EC), total dissolved solid (TDS), Na, K, Ca, Mg, Fe, Mn, Zn, Cu, NO3-N, SO4-S, CO3, HCO3, Cl and total hardness (HT) were analyzed. pH of waters were just neutral to alkaline in nature. EC and TDS values varied from 165 to 1770 μS cm ̄1 and 100 to 1020 mg L ̄1, respectively. Appreciable amount of Ca and Mg were present resulting higher water hardness. The Na concentration was as high as 5.98 to 389.99 mg L ̄1. Cl was dominant among the ionic constituents. Fe, Mn, Zn, Cu, NO3-N and SO4-S concentrations were within the safety limit. Significant amounts of Cl were detected in drinking waters exceeding the level of U.S. Environmental Protection Agency (USEPA). The result of present findings indicated that groundwater contained some chemical parameters that exceeded the upper limit of standard. WASA water was found suitable in all respect while some groundwater samples were unsuitable for drinking and domestic purposes.
Contaminated Small Drinking Water Supplies and Risk of Infectious Intestinal Disease: A Prospective Cohort Study  [PDF]
Helen L. Risebro, Lynette Breton, Heather Aird, Alan Hooper, Paul R. Hunter
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0042762
Abstract: Background This study sought to identify whether elevated risk of infectious intestinal disease (IID) exists in contaminated small water supply consumers compared with consumers drinking from small supplies complying with current standards and whether this effect is modified by age. Methodology and Principal Findings A prospective cohort study of 611 individuals receiving small supplies in England was conducted. Water supplies received sanitary inspection and examination for indicator bacteria and participants maintained a daily record of IID. Regression modeling with generalized estimating equations that included interaction terms between age and indicators of fecal pollution was performed. Crude IID prevalence was 9·3 days with symptoms/1000 person days (95%CI: 8·4, 10·1) and incidence was 3·2 episodes/1000 person days (95%CI, 2·7, 3·7) or 1·2 episodes per person year. Although there was no overall association between IID risk and indicator presence, there was strong interaction between age and indicator presence. In children under ten, relative risk (RR) of IID in those drinking from enterococci contaminated supplies was 4.8 (95%CI: 1.5, 15.3) for incidence and 8.9 (95%CI: 2.8, 27.5) for prevalence. In those aged 10 to 59, IID risk was lower but not statistically significant. Conclusions Contaminated small water supplies pose a substantial risk of IID to young children who live in homes reliant on these supplies. By contrast older children and adults do not appear to be at increased risk. Health care professionals with responsibility for children living in homes provided by very small water supplies should make parents aware of the risk.
Exposure assessment of radon in the drinking water supplies: a descriptive study in Palestine
Hamzeh Al Zabadi, Samar Musmar, Shaza Issa, Nidal Dwaikat, Ghassan Saffarini
BMC Research Notes , 2012, DOI: 10.1186/1756-0500-5-29
Abstract: This was a descriptive study carried out in two phases with a random sampling technique in the second phase. Primarily, samples were taken from 4 wells and 5 springs that supplied Nablus city residents. For each source, 3 samples were taken and each was analyzed in 4 cycles by RAD 7 device manufactured by Durridge Company. Secondly, from the seven regions of the Nablus city, three samples were taken from the residential tap water of each region. Regarding the old city, ten samples were taken. Finally, the mean radon concentration value for each source was calculated.The mean (range) concentration of radon in the main sources were 6.9 (1.5-23.4) Becquerel/liter (Bq/L). Separately, springs and wells' means were 4.6 Bq/L and 9.5 Bq/L; respectively. For the residential tap water in the 7 regions, the results of the mean (range) concentration values were found to be 1.0 (0.9-1.3) Bq/L. For the old city, the mean (range) concentration values were 2.3 (0.9-3.9) Bq/L.Except for Al-Badan well, radon concentrations in the wells and springs were below the United State Environmental Protection Agency maximum contaminated level (U.S EPA MCL). The level was much lower for tap water. Although the concentration of radon in the tap water of old city were below the MCL, it was higher than other regions in the city. Preventive measures and population awareness on radon's exposure are recommended.Radon is a colorless, odorless and tasteless gas. It is a chemically and biologically inert noble gas with a heavily neutron-rich nucleus that makes it a radioactive element [1]. It has three main natural isotopes; radon-222 (Rn-222); radon-220 (Rn-220 also known as thoron); and radon-219 (Rn-219) [2]. Rocky, mountainous regions and phosphate rich soil regions and water, all over the world, tend to have varying amounts of Rn-222 [3,4]. Radon is unstable and breaks down into radon progeny emitting highly ionizing alpha radiation which is very harmful to humans when they are inhaled or swallowed
A case study of sanitary survey on community drinking water supplies after a severe (post-Tsunami) flooding event
Ferretti,Emanuele; Bonadonna,Lucia; Lucentini,Luca; Della Libera,Simonetta; Semproni,Maurizio; Ottaviani,Massimo;
Annali dell'Istituto Superiore di Sanità , 2010, DOI: 10.1590/S0021-25712010000300003
Abstract: this report presents a case study of a comprehensive sanitary survey on ca. 160 community drinking water supplies after a severe (post-tsunami) flooding event in sri lanka. sanitary inspection and microbiological and chemical water quality analyses were performed according to specifically-designed procedures established on the world health organization (who) guidelines. significant hazards and critical points were identified in almost all the investigated water supplies. the overall results showed a significant level of microbiological and chemical risk associated with drinking water consumption within the investigated areas. the criteria and methods practised in this study are proposed as a model to assure an effective and reliable monitoring in post-emergencies involving possible deterioration of water quality and to identify health priorities related to water consumption.
Spatial variations of aluminum species in drinking water supplies in Xi''an studied applying geographic information system
Spatial variations of aluminum species in drinking water supplies in Xi'an studied applying geographic information system

Wendong Wang,Hua Li,Xiaochang Wang,Yongjun Liu,
Wendong Wang
,Hua Li,Xiaochang Wang,Yongjun Liu

环境科学学报(英文版) , 2010,
Abstract: This article aimed to investigate the variation of aluminum species and the effects of coagulant type and water quality on aluminum speciation in drinking water. Statistical analysis showed that the concentration of total aluminum (Al_T) of drinking water in Xi'an ranged from 0.051 to 0.417 mg/L and the concentration of Al_T in about 24.7% studied samples was higher than the currently recommended value (0.2 mg/L). The areas fed by surface water plants had a larger portion (39.4%) of samples over the recommended value. In drinking water treated by alum coagulant, the average concentration of monomeric aluminum (Al_a) was higher than that in water treated by poly aluminum chlorine (PACl) and poly aluminum ferric chloride (PAFC). The average concentrations of polynuclear aluminum (Al_b) and colloidal/suspended aluminum (Al_c) in the drinking water treated by alum were lower than those in water treated by PACl and PAFC. There was a notable decrease in Al_T along with the delivery pipeline away from the plants, with an average decline of about 36 (μg/(L·km). Besides coagulant type, water quality also could affect aluminum speciation. In drinking water without orthophosphate, the concentrations of Al_a and Al_T were positively correlated with pH; while, in drinking water with orthophosphate, the concentrations of Al_a and Al_T were negatively correlated with pH. The addition of orthophosphate salts in the drinking water treatment process would be an effective method for aluminum control in pH range 6.5-8.2.
Determining the Maximum Cumulative Ratios for Mixtures Observed in Ground Water Wells Used as Drinking Water Supplies in the United States  [PDF]
Xianglu Han,Paul S. Price
International Journal of Environmental Research and Public Health , 2011, DOI: 10.3390/ijerph8124729
Abstract: The maximum cumulative ratio (MCR) developed in previous work is a tool to evaluate the need to perform cumulative risk assessments. MCR is the ratio of the cumulative exposures to multiple chemicals to the maximum exposure from one of the chemicals when exposures are described using a common metric. This tool is used to evaluate mixtures of chemicals measured in samples of untreated ground water as source for drinking water systems in the United States. The mixtures of chemicals in this dataset differ from those examined in our previous work both in terms of the predicted toxicity and compounds measured. Despite these differences, MCR values in this study follow patterns similar to those seen earlier. MCR values for the mixtures have a mean (range) of 2.2 (1.03–5.4) that is much smaller than the mean (range) of 16 (5–34) in the mixtures in previous study. The MCR values of the mixtures decline as Hazard Index (HI) values increase. MCR values for mixtures with larger HI values are not affected by possible contributions from chemicals that may occur at levels below the detection limits. This work provides a second example of use of the MCR tool in the evaluation of mixtures that occur in the environment.
Atrazine and Nitrate in Public Drinking Water Supplies and Non-Hodgkin Lymphoma in Nebraska, USA
Martha G. Rhoades, Jane L. Meza, Cheryl L. Beseler, Patrick J. Shea, Andy Kahle, Julie M. Vose, Kent M. Eskridge and Roy F. Spalding
Environmental Health Insights , 2012, DOI: 10.4137/EHI.S10629
Abstract: A secondary analysis of 1999–2002 Nebraska case-control data was conducted to assess the risk of non-Hodgkin lymphoma (NHL) associated with exposure to nitrate- and atrazine-contaminated drinking water. Water chemistry data were collected and weighted by well contribution and proximity of residence to water supply, followed by logistic regression to determine odds ratios (OR) and 95% confidence intervals (CI). We found no association between NHL risk and exposure to drinking water containing atrazine or nitrate alone. Risk associated with the interaction of nitrate and atrazine in drinking water was elevated (OR, 2.5; CI, 1.0–6.2). Risk of indolent B-cell lymphoma was higher than risk of aggressive B-cell lymphoma (indolent: OR, 3.5; CI, 1.0–11.6 vs. aggressive: OR, 1.9; CI, 0.6–5.58). This increased risk may be due to in vivo formation and subsequent metabolism of N-nitrosoatrazine. A larger study is warranted to confirm our findings.
Evaluation of media for simultaneous enumeration of total coliform and Escherichia coli in drinking water supplies by membrane filtration techniques
WANG Dunling,FIESSEL Wanda,
WANG Dunling

环境科学学报(英文版) , 2008,
Abstract: This study evaluated three different dehydrated media for simultaneous detection and enumeration of total coliform (TC) and Escherichia coil in drinking water samples with a standard membrane filtration procedure.The experiment indicated that the differential coliform agar (DCA) medium was the most effective among the tested media in enumerating TC and E.coli,without the need for extensive accompanying confirmation tests.The results for DCA medium were highly reproducible for both TC and E.coli with standard deviation of 6.0 and 6.1,respectively.A high agreement (82%) was found between DCA and m-Endo media on 152 drinking water samples in terms of TC positive.The DCA medium also reduced concealment of background bacteria.
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