Point-of-use water filters can effectively remove disinfection by-products and toxicity from chlorinated and chloraminated tap water

2016 ◽  
Vol 2 (5) ◽  
pp. 875-883 ◽  
Author(s):  
Daniel Stalter ◽  
Elissa O'Malley ◽  
Urs von Gunten ◽  
Beate I. Escher
Keyword(s):  
Tap Water ◽  
Point Of Use ◽  
Organic Halogens ◽  
Water Filters ◽  
By Products ◽  
Adsorbable Organic Halogens

Tap water filters were evaluated for their efficacy to abate fluoride, bacteria, adsorbable organic halogens (sum parameter of halogenated DBPs), and mixtures of bioactive DBPs quantified by cell-based bioassays.

scholarly journals The microbial colonization of activated carbon block point-of-use (PoU) filters with and without chlorinated phenol disinfection by-products

2017 ◽  
Vol 3 (5) ◽  
pp. 830-843 ◽  
Author(s):  
Chia-Chen Wu ◽  
Sudeshna Ghosh ◽  
Kelly J. Martin ◽  
Ameet J. Pinto ◽  
Vincent J. Denef ◽  
...  
Keyword(s):  
Drinking Water ◽  
Activated Carbon ◽  
Bacterial Community Structure ◽  
Microbial Colonization ◽  
Opportunistic Pathogens ◽  
Absolute Abundance ◽  
Carbon Block ◽  
Point Of Use ◽  
Water Filters ◽  
By Products

Activated carbon based point-of-use drinking water filters change the bacterial community structure and increase the absolute abundance of genera, including those associated with opportunistic pathogens.

CHEMICAL PULPING. Oxidative degradation of AOX in softwood-based kraft mill effluents from E C F bleachin g

2012 ◽  
Vol 27 (4) ◽  
pp. 707-713 ◽  
Author(s):  
Jukka Pekka lsoaho ◽  
Suvi Tarkkanen ◽  
Raimo Alen ◽  
Juha Fiskari
Keyword(s):  
Reaction Time ◽  
Oxidative Degradation ◽  
Cost Effective ◽  
Process Conditions ◽  
Main Process ◽  
Chemical Pulping ◽  
Kraft Mill ◽  
Organic Halogens ◽  
Aox Removal ◽  
Adsorbable Organic Halogens

Abstract Softwood-based kraft mill bleaching effluents from the initial bleaching stages D0 and E1 (the bleaching sequence being D0E 1D 1 E2D2) were treated by the oxidative Fenton method (H20rFeS04) to decompose organic pollutants contammg adsorbable organic halogens (AOX). Experiments designed using the Taguchi method were applied to predict the process conditions that would result in a cost-effective and adequate removal of AOX. In addition to the composition and concentration of the reagents (H202 and Fe2+), the main process parameters selected were temperature and reaction time, while pH was adj usted to an approximate value of 4 (the volumetric ratio of the mixed effluents D0:E 1 was 3 :2). The results indicated that an AOX removal of about 70% for this mixture ( corresponding to about 50% for the mill) was achieved when the eftluent samples were treated for 60 min at 70°C with H202 and Fe2+ at a concentration of 1 600 mg/1 and 28 mg/1, respectively.

scholarly journals Polyphenol Profiling of Chestnut Pericarp, Integument and Curing Water Extracts to Qualify These Food By-Products as a Source of Antioxidants

Molecules ◽  
2021 ◽  
Vol 26 (8) ◽  
pp. 2335
Author(s):  
Gabriella Pinto ◽  
Sabrina De Pascale ◽  
Maria Aponte ◽  
Andrea Scaloni ◽  
Francesco Addeo ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Negative Impact ◽  
Tap Water ◽  
Time Of Flight ◽  
The Other ◽  
Curing Process ◽  
Flight Mass Spectrometry ◽  
Water Curing ◽  
The Impact ◽  
By Products

Plant polyphenols have beneficial antioxidant effects on human health; practices aimed at preserving their content in foods and/or reusing food by-products are encouraged. The impact of the traditional practice of the water curing procedure of chestnuts, which prevents insect/mould damage during storage, was studied to assess the release of polyphenols from the fruit. Metabolites extracted from pericarp and integument tissues or released in the medium from the water curing process were analyzed by matrix-assisted laser desorption ionization-time of flight-mass spectrometry (MALDI-TOF-MS) and electrospray-quadrupole-time of flight-mass spectrometry (ESI-qTOF-MS). This identified: (i) condensed and hydrolyzable tannins made of (epi)catechin (procyanidins) and acid ellagic units in pericarp tissues; (ii) polyphenols made of gallocatechin and catechin units condensed with gallate (prodelphinidins) in integument counterparts; (iii) metabolites resembling those reported above in the wastewater from the chestnut curing process. Comparative experiments were also performed on aqueous media recovered from fruits treated with processes involving: (i) tap water; (ii) tap water containing an antifungal Lb. pentosus strain; (iii) wastewater from a previous curing treatment. These analyses indicated that the former treatment determines a 6–7-fold higher release of polyphenols in the curing water with respect to the other ones. This event has a negative impact on the luster of treated fruits but qualifies the corresponding wastes as a source of antioxidants. Such a phenomenon does not occur in wastewater from the other curing processes, where the release of polyphenols was reduced, thus preserving the chestnut’s appearance. Polyphenol profiling measurements demonstrated that bacterial presence in water hampered the release of pericarp metabolites. This study provides a rationale to traditional processing practices on fruit appearance and qualifies the corresponding wastes as a source of bioactive compounds for other nutraceutical applications.

scholarly journals Under-Sink Activated Carbon Water Filters Effectively Remove Lead from Private Well Water for over Six Months

Water ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 3584
Author(s):  
Riley Mulhern ◽  
Jacqueline MacDonald Gibson
Keyword(s):  
Activated Carbon ◽  
Blood Lead ◽  
The United States ◽  
Well Water ◽  
Point Of Use ◽  
Metals Removal ◽  
Lead Levels ◽  
Minimal Data ◽  
Water Filters ◽  
Private Wells

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.

Adsorbable Organic Halogens Generation and Reduction During Degradation of Phenol by UV Radiation/Sodium Hypochlorite

2009 ◽  
Vol 81 (2) ◽  
pp. 178-183 ◽  
Author(s):  
Qing-fu Zeng ◽  
Jie Fu ◽  
Yin-tao Shi ◽  
Dong-sheng Xia ◽  
Hai-liang Zhu
Keyword(s):  
Uv Radiation ◽  
Sodium Hypochlorite ◽  
Organic Halogens ◽  
Adsorbable Organic Halogens

Virus removal efficiency of ceramic water filters: effects of bentonite turbidity

2013 ◽  
Vol 14 (2) ◽  
pp. 304-311 ◽  
Author(s):  
Cameron Farrow ◽  
Edward McBean ◽  
Hamidreza Salsali
Keyword(s):  
Removal Efficiency ◽  
Potable Water ◽  
Source Water ◽  
Virus Removal ◽  
Ceramic Water Filters ◽  
Point Of Use ◽  
Cake Layer ◽  
Human Enteric Viruses ◽  
Removal Efficiencies ◽  
Water Filters

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.

Presence and formation of disinfection by-products in Cairo residential water supply

2009 ◽  
Vol 9 (2) ◽  
pp. 113-120 ◽  
Author(s):  
E. H. Smith ◽  
K. E. El-Deen
Keyword(s):  
Natural Organic Matter ◽  
Distribution System ◽  
Tap Water ◽  
Residential Community ◽  
Chlorine Disinfection ◽  
Sampling Program ◽  
The Impact ◽  
By Products ◽  
The U.S ◽  
Residential Water

A sampling program was conducted in a residential community in Cairo, Egypt in order to determine the presence of chlorine disinfection by-products (DBPs) in treated water and to observe the impact of the distribution system on DBP levels. Five campaigns were conducted over a 15-month period during 2005–2006. Trihalomethanes (THMs) and haloacetic acids (HAAs) exceeded local and international limits depending upon the season. Tap water concentrations of THMs were considerably higher in summer than during the rest of the year. In the Summer 2005 event, the average for the 20 tap water locations was 158 μg/l Total-THMs, well in excess of the U.S. EPA limit of 80 μg/L and the current Egyptian standard of 100 μg/l; all 20 locations exceeded the 100 μg/l limit. For the following event in late Fall 2005, the average dropped to 84 μg/l with 11 and 6 sites exceeding the U.S. EPA and Egyptian limits, respectively. HAA levels tended to be complementary to Total-THM values in that they were lower in summer but higher during fall and spring. The U.S. EPA limit on a select set of 5 HAAs (HAA5) is 60 μg/l (Egypt does not currently regulate HAAs). The average for HAA5 in the Summer 2005 event was 52 μg/l with 8 of the 20 tap samples equalling or exceeding the 60 μg/l standard. By contrast, in Fall 2005, the HAA5 average increased to 89 μg/l, with 15 of 20 sites exceeding the limit. THM and HAA concentrations generally increased with distance from the WTP along a targeted distribution main, while chlorine and natural organic matter tended to decrease.

Comparative study of degradation of 4-chlorophenol by ultraviolet irradiation/sodium hypochlorite and ultraviolet irradiation/ozonation

2009 ◽  
Vol 9 (5) ◽  
pp. 601-609 ◽  
Author(s):  
J. Fu ◽  
J. Huang ◽  
Z. Liu ◽  
Q. F. Zeng ◽  
S. Q. An ◽  
...  
Keyword(s):  
Sodium Hypochlorite ◽  
Ultraviolet Irradiation ◽  
Pilot Scale ◽  
Economic Advantage ◽  
Photochemical Oxidation ◽  
Small Scale ◽  
Final Solution ◽  
Ph Values ◽  
Organic Halogens ◽  
Adsorbable Organic Halogens

The photochemical oxidation of 4-chlorophenol solutions by ultraviolet irradiation/sodium hypochlorite (UV/NaClO) and ultraviolet irradiation/ozonation (UV/O3) respectively was studied in a pilot scale photochemical reactor. The degradation efficiency of UV/NaClO was lower than that of UV/O3. The final UV absorption removals of the two processes were approximately 80% and approximately 90% respectively. During the two processes, dihydroxylated chlorophenols were the main intermediates. And pH values decreased with the oxidation being carried on. However, the UV/NaClO process was incomplete and some adsorbable organic halogens, such as ethyl 2-chloroacetate, 3,4-dichlorobut-3-en-2-one, ethyl 2,2-dichloroacetate, 2-chloro-1,1-diethoxyethane, ethyl 2,2,2-trichloroacetate and 2,4,6-trichlorophenol, still existed in the final solution. The costs of the two processes were also estimated. On a small scale, UV/NaClO process had significant economic advantage.

Sustainable Water Filters for the Developing World: A Focus on Cholera

2016 ◽  
Author(s):  
Andrew Krentz ◽  
Ryan Magowan ◽  
Liane Millington
Keyword(s):  
Vibrio Cholerae ◽  
Water Filtration ◽  
Human Populations ◽  
Human Waste ◽  
Geological Materials ◽  
Point Of Use ◽  
Filtration Unit ◽  
Water Filters ◽  
Filtration Device ◽  
Water Borne

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.

Participant responses to a water treatment intervention in rural Guatemala

2020 ◽  
Vol 19 (5-6) ◽  
pp. 792-809
Author(s):  
Lissette M Piedra ◽  
Lenore E Matthew ◽  
Chi-Fang Wu
Keyword(s):  
International Development ◽  
Water Remediation ◽  
Illustrative Case ◽  
Culturally Competent ◽  
Point Of Use ◽  
Use Of Technology ◽  
Viable Solution ◽  
Service Barriers ◽  
Health Promoting ◽  
Water Filters

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.

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