Standard Practice for Pre-Stressing Terminal Point-of-Use Water Filters before Testing by Test Method

10.1520/d8422 ◽  
2022 ◽  
Author(s):  
Water ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 3584
Author(s):  
Riley Mulhern ◽  
Jacqueline MacDonald Gibson

Children who rely on private well water in the United States have been shown to be at greater risk of having elevated blood lead levels. Evidence-based solutions are needed to prevent drinking water lead exposure among private well users, but minimal data are available regarding the real-world effectiveness of available interventions like point-of-use water treatment for well water. In this study, under-sink activated carbon block water filters were tested for lead and other heavy metals removal in an eight-month longitudinal study in 17 homes relying on private wells. The device removed 98% of all influent lead for the entirety of the study, with all effluent lead levels less than 1 µg/L. Profile sampling in a subset of homes showed that the faucet fixture is a significant source of lead leaching where well water is corrosive. Flushing alone was not capable of reducing first-draw lead to levels below 1 µg/L, but the under-sink filter was found to increase the safety and effectiveness of faucet flushing. The results of this study can be used by individual well users and policymakers alike to improve decision-making around the use of under-sink point-of-use devices to prevent disproportionate lead exposures among private well users.


2013 ◽  
Vol 14 (2) ◽  
pp. 304-311 ◽  
Author(s):  
Cameron Farrow ◽  
Edward McBean ◽  
Hamidreza Salsali

Ceramic water filters (CWFs) are utilized in many developing countries as point-of-use (POU) water treatment devices, to reduce waterborne pathogens in potable water. Virus removal efficiencies of several CWFs are investigated under various influent conditions using MS2 (ATCC: 15597-B1) as a surrogate phage for human enteric viruses. The addition of bentonite turbidity (6–8 NTU) in the influent source water showed increased viral removal efficiency of CWFs by 0.1–0.2 log compared to tests involving clear (<1 NTU) influents. Trials employing an applied clay cake layer, formed using highly turbid influent source water (100 NTU) and no cleaning regime between trials, resulted in viral removal efficiency values of 1.5–2.5 log, compared to 0.2–0.5 log during non-obstructed trials.


Author(s):  
Andrew Krentz ◽  
Ryan Magowan ◽  
Liane Millington

The goal of this project is to design a point-of-use water filtration device constructed from locally available geological materials, which is capable of filtering out Vibrio cholerae bacteria. Vibrio cholerae occurs naturally in tropical seawater, as well as in human waste. It is a water-borne pathogen, and thus human populations are especially vulnerable during and after natural crises such as floods, tsunamis and earthquakes. The basic filtration unit uses readily available supplies including pop bottles, fabric (such as that from a T-shirt), and a geologic material, such as sand, clay or zeolites. Tests utilizing yeast as a surrogate for Vibrio cholerae are currently ongoing.


2020 ◽  
Vol 19 (5-6) ◽  
pp. 792-809
Author(s):  
Lissette M Piedra ◽  
Lenore E Matthew ◽  
Chi-Fang Wu

Each year, 1.1 billion people suffer from disease, dehydration, and malnutrition fueled by waterborne pathogens. Although point-of-use water filters are a viable solution, effectiveness requires consistent use. As collaborators in international development projects, social workers are poised to address service barriers through their focus on multilevel practice and a relentless emphasis on culturally competent practice. This article describes an illustrative case of a water remediation project in rural Guatemala where social work researchers collaborated with engineers to understand how users appraised the project. We present a content analysis of interviews conducted in 20 households in the Boca Costa and Highland regions of rural Guatemala that received bio-sand water filters, which revealed a diverse group of filter users, with varying motivations and constancy patterns. Our study demonstrates how talking to people is essential to understanding their use of technology and how other objective measures—such as the wetness of the sand—can be helpful in interpreting results. It also shows that within the developing context, people vary in their need for additional supports as they adopt new health-promoting activities.


2001 ◽  
Vol 64 (10) ◽  
pp. 1477-1482 ◽  
Author(s):  
LINDA J. HARRIS ◽  
LARRY R. BEUCHAT ◽  
THERESA M. KAJS ◽  
THOMAS E. WARD ◽  
CHARLES H. TAYLOR

The reproducibility of a method developed to evaluate point-of-use sanitizers for fresh produce was tested at three different laboratories. Mixtures of five Salmonella serotypes were inoculated on the surface of ripe tomatoes. After the inoculum was dry, tomatoes were placed inside a plastic bag and sprayed with sterile USP water, Dey and Engley (D/E) neutralizer broth, or a prototype Fit produce wash (PW), an alkaline solution comprised of generally recognized as safe ingredients (water, oleic acid, glycerol, ethanol, potassium hydroxide, sodium bicarbonate, citric acid, and distilled grapefruit oil), and rubbed for 30 s. The tomatoes were rinsed 10 s with 195 ml of D/E neutralizer broth (rinse solution), then combined with 20 ml of D/E neutralizer (residual wash solution) and rubbed by hand to remove residual Salmonella. Populations of Salmonella were determined for each tomato in the rinse solution and residual wash solution. Treatment with PW resulted in reductions in the number of Salmonella 2 to 4 logs greater than those achieved with the sterile water or D/E neutralizer broth controls. Consistent results were obtained across the three study sites, indicating reproducible results were obtained using the test method. The method used to determine the efficacy of killing or removing Salmonella from tomatoes in this study is suggested as a standard method for measuring the efficacy of sanitizers on tomatoes and other similar fruits and vegetables with rigid, smooth surfaces.


2010 ◽  
Vol 10 (3) ◽  
pp. 286-295 ◽  
Author(s):  
H. M. Murphy ◽  
M. Sampson ◽  
K. Farahbakhsh ◽  
E. McBean

Unless significant advances are made in the water and sanitation sector, it is unlikely that Cambodia will meet the United Nations Millennium Development Goal (MDG) target #7 for water and sanitation. Point-of-use technologies (POU), also termed “household water treatment technologies”, have been identified as successful options for providing safe water to rural households. Ceramic water filters and BioSand filters are two major POU technologies that are currently implemented across Cambodia. This paper presents data on the microbial performance of these two technologies in the field on various Cambodian source waters. In addition, data are presented on the occurrence of nitrite in treated water. Results showed that 61% and 88% of BioSand filters and ceramic filters, respectively, produced water in the low risk range for E. coli as defined by the WHO (0–10 CFU/100 mL). In addition, 83% of BioSand filters and 75% of ceramic filters were not meeting the WHO guideline value for chronic exposure to nitrite in drinking water (0.2 mg/L).


Chemosphere ◽  
2017 ◽  
Vol 173 ◽  
pp. 632
Author(s):  
Kate Smith ◽  
Zhenyu Li ◽  
Bohan Chen ◽  
Honggang Liang ◽  
Xinyi Zhang ◽  
...  

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