Silver Dissolution and Release from Ceramic Water Filters. Env Sci Tech, June 2015.

Authors: Anjuliee M. Mittelman, Daniele S. Lantagne, Justine Rayner, and Kurt D. Pennell

Application of silver nanoparticles (nAg) or silver nitrate (AgNO3) has been shown to improve the microbiological efficacy of ceramic water filters used for household water treatment. Silver release, however, can lead to undesirable health effects and reduced filter effectiveness over time. The objectives of this study were to evaluate the contribution of nanoparticle detachment, dissolution, and cation exchange to silver elution, and to estimate silver retention under different influent water chemistries. Dissolved silver (Ag+) and nAg release from filter disks painted with 0.03 mg/g casein-coated nAg or AgNO3 were measured as a function of pH (5–9), ionic strength (1–50 mM), and cation species (Na+, Ca2+, Mg2+).

Silver elution was controlled by dissolution as Ag+ and subsequent cation exchange reactions regardless of the applied silver form. Effluent silver levels fell below the drinking water standard (0.1 mg/L) after flushing with 30–42 pore volumes of pH 7, 10 mM NaNO3 at pH 7. When the influent water was at pH 5, contained divalent cations or 50 mM NaNO3, silver concentrations were 5–10 times above the standard. Our findings support regular filter replacement and indicate that saline, hard, or acidic waters should be avoided to minimize effluent silver concentrations and preserve silver treatment integrity.

Efficacy of Handwashing with Soap and Nail Clipping on Intestinal Parasitic Infections in School-Aged Children: A Factorial Cluster Randomized Controlled Trial. PLoS Medicine, June 2015.

Authors: Mahmud Abdulkader Mahmud, Mark Spigt, et al.

Background - Intestinal parasitic infections are highly endemic among school-aged children in resource-limited settings. To lower their impact, preventive measures should be implemented that are sustainable with available resources. The aim of this study was to assess the impact of handwashing with soap and nail clipping on the prevention of intestinal parasite reinfections.

Methods and Findings - In this trial, 367 parasite-negative school-aged children (aged 6–15 y) were randomly assigned to receive both, one or the other, or neither of the interventions in a 2 × 2 factorial design. Assignment sequence was concealed. After 6 mo of follow-up, stool samples were examined using direct, concentration, and Kato-Katz methods. Hemoglobin levels were determined using a HemoCue spectrometer. The primary study outcomes were prevalence of intestinal parasite reinfection and infection intensity. The secondary outcome was anemia prevalence. Analysis was by intention to treat. Main effects were adjusted for sex, age, drinking water source, latrine use, pre-treatment parasites, handwashing with soap and nail clipping at baseline, and the other factor in the additive model. Fourteen percent (95% CI: 9% to 19%) of the children in the handwashing with soap intervention group were reinfected versus 29% (95% CI: 22% to 36%) in the groups with no handwashing with soap (adjusted odds ratio [AOR] 0.32, 95% CI: 0.17 to 0.62). Similarly, 17% (95% CI: 12% to 22%) of the children in the nail clipping intervention group were reinfected versus 26% (95% CI: 20% to 32%) in the groups with no nail clipping (AOR 0.51, 95% CI: 0.27 to 0.95). Likewise, following the intervention, 13% (95% CI: 8% to 18%) of the children in the handwashing group were anemic versus 23% (95% CI: 17% to 29%) in the groups with no handwashing with soap (AOR 0.39, 95% CI: 0.20 to 0.78). The prevalence of anemia did not differ significantly between children in the nail clipping group and those in the groups with no nail clipping (AOR 0.53, 95% CI: 0.27 to 1.04). The intensive follow-up and monitoring during this study made it such that the assessment of the observed intervention benefits was under rather ideal circumstances, and hence the study could possibly overestimate the effects when compared to usual conditions.

Conclusions - Handwashing with soap at key times and weekly nail clipping significantly decreased intestinal parasite reinfection rates. Furthermore, the handwashing intervention significantly reduced anemia prevalence in children. The next essential step should be implementing pragmatic studies and developing more effective approaches to promote and implement handwashing with soap and nail clipping at larger scales.

 

Factors Determining Water Treatment Behavior for the Prevention of Cholera in Chad. Am Jnl Trop Med Hyg, Apr 2015.

Authors: Jonathan Lilje, Hamit Kessely and Hans-Joachim Mosler

Cholera is a well-known and feared disease in developing countries, and is linked to high rates of morbidity and mortality. Contaminated drinking water and the lack of sufficient treatment are two of the key causes of high transmission rates. This article presents a representative health survey performed in Chad to inform future intervention strategies in the prevention and control of cholera.

To identify critical psychological factors for behavior change, structured household interviews were administered to N = 1,017 primary caregivers, assessing their thoughts and attitudes toward household water treatment according to the Risk, Attitude, Norm, Ability, and Self-regulation model. The intervention potential for each factor was estimated by analyzing differences in means between groups of current performers and nonperformers of water treatment. Personal risk evaluation for diarrheal diseases and particularly for cholera was very low among the study population. Likewise, the perception of social norms was found to be rather unfavorable for water treatment behaviors.

n addition, self-reported ability estimates (self-efficacy) revealed some potential for intervention. A mass radio campaign is proposed, using information and normative behavior change techniques, in combination with community meetings focused on targeting abilities and personal commitment to water treatment.

Evaluation of Microbial Water Quality Tests for Humanitarian Emergency and Development SettingsProcedia Engineering, Volume 107, 2015, Pages 237–246. Humanitarian Technology: Science, Systems and Global Impact 2015, HumTech2015.

Authors: Susan Murcott, Megan Keegan, Alison Hanson, Akshay Jain, Jason Knutson, Shuyue Liu, Jenny Tanphanich, Teng Ke Wong

How do you know if drinking water is safe? Or which microbial indicator tests work best when few side-by-side performance evaluations exist in real-world field sites? This research compares bacterial indicator test products inlow-resource settings in Ahmedabad, India and Tamale, Ghana. In India, three hydrogen sulfide (H2S) bacteria test products were evaluated: laboratory-made H2S, TARA Aquacheck and ORlab H2S, and compared to an EPA-certified standard, the IDEXX Quanti-Tray® 2000. In Ghana, 3 M Petrifilm™, Aquagenx CBT and Easygel® Cards were included in addition toH2S and Quanti-Tray® 2000. Results are presented in a Consumer Reports-style for easy comprehension.

Sanitary Survey of Public Drinking Water Sources: A Study Conducted in Slums of Bhubaneswar, Odisha, 2015. Health of the Urban Poor (HUP) Program.

Authors: Biraja Kabi Satapathy, Niladri Chakraborti.

The sanitary survey of drinking water sources was done in Bhubaneswar slums where PFI is running the Health of the Urban Poor Program. The purpose was to understand the risk to public drinking water sources based on onsite inspection and water testing of the source with field test for pipe water supply and H2 S bacteriological contamination test for all the sources. The study report gives details of the survey undertaken, its findings, and suggestions for ensuring drinking water quality in the slums of Odisha. The report tried to capture the result of the indicator-wise sanitary inspection and its relation with other indicators. We hope the study will be useful for the government for making some policy level corrections. We also hope that Government, Non Government and civil society organisations will adopt the sanitary survey as a tool for identifying factors that affect drinking water sources, which is essential for drinking water safety.

What factors affect sustained adoption of safe water, hygiene and sanitation technologies?A systematic review of literature, June 2015. EPPI-Centre, Social Science Research Unit, UCL Institute of Education, University College London.

Authors: Kristyna Hulland, Nina Martin, Robert Dreibelbis, Julia DeBruicker Valliant, Peter Winch

Among the exciting advances in water, sanitation, and hygiene (WASH) programmes and policies, sustainability counts as a renewed and crucial area of focus for implementers, scientists, policy makers, and donors alike. To further our understanding of the barriers and facilitators to sustained adoption and use of water and sanitation technologies, we conducted a systematic review of studies concerning both initial and sustained adoption of WASH interventions at the individual, household and community levels in low- and middleincome countries. We built on previous reviews of handwashing and point-of-use water treatment, with a comprehensive review that is dramatically larger and broader in scope than previous studies. It is the only review we know of that includes a range of WASH interventions and factors associated with adoption.

 

Fecal Coliform Contamination of Drinking Water: An Evaluation of World Field Assessment Techniques. EWB-USA Technical Paper 104.

Authors: William Fripp, Catherine Dane Woodyard, PhD, and Marina Hanna

A safe, consistent, and reliable water supply is a universal need. However, a large number of the world’s population lives in areas that are suffering from water quality problems and water shortages. Many areas have contaminated water with fecal coliform bacteria as the primary contaminant of concern. As a result, there are many aid groups that are actively working to develop and improve the water supply in the developing world.

An important first step in such work is an accurate appraisal of the existing water supply. This appraisal often requires a rapid, onsite field assessment of possible fecal coliform contamination with minimal equipment. This paper summarizes a qualitative evaluation of five field assessment techniques undertaken by an interdisciplinary team of students involved in aid work. The focus of this evaluation is on Presence/Absence testing.

The evaluation examines usability, accuracy, cost, speed of results, and ease of explaining results to the local population. Advantages and disadvantages of each technique have been identified and discussed. The purpose of this paper is to provide guidance that will aid in the selection of a suitable rapid fecal coliform field test. The team performed their assessments of the five techniques in the United States under controlled situations, as well as during an evaluation trip to Belize.

All of the evaluations were conducted under the oversight of a professional engineer with experience in water quality assessments and water treatment design. This study and paper is of value to aid groups involved in the assessment of water projects in the developing world.

Household Water Quantity and Health: A Systematic Review. Int. J. Environ. Res. Public Health 2015, 12(6), 5954-5974

Authors: Rachel D. Stelmach and Thomas Clasen

While the quantity of water used in the home is thought to be an important determinant of health, much of the evidence relies on using water access as a proxy for quantity. This review examines the health effects of household water quantity using studies that directly measured water quantity.

We searched MEDLINE, EMBASE, the Cochrane Library, Web of Science, and article reference lists. Eligible studies included experimental and observational studies that measured a difference in water quantity and quantified an association between water quantity and health outcomes. 21 studies, divided into six of the many possible water-quantity associated outcomes, met the eligibility criteria. Due to heterogeneity in designs, settings, methods, and outcomes, a meta-analysis was inappropriate.

Overall results showed a positive association between water quantity and health outcomes, but the effect depended on how the water was used. Increased water usage for personal hygiene was generally associated with improved trachoma outcomes, while increased water consumption was generally associated with reduced gastrointestinal infection and diarrheal disease and improved growth outcomes.

In high-income countries, increased water consumption was associated with higher rates of renal cell carcinoma and bladder cancer but not associated with type II diabetes, cardiac-related mortality, or all-cause mortality.

USAID WASH and Nutrition Webinar, May 2015

Overcoming undernutrition is a great challenge that will require both WASH and nutrition interventions. usaid

USAID’s Elizabeth Jordan and Katherine Dennison discuss the connection between undernutrition and lack of access to water, sanitation and hygiene (WASH) services and highlight opportunities for integrated programming to achieve better health outcomes.

E. coli from dishcloths as an indicator of hygienic status in households. Journal of Water, Sanitation and Hygiene for Development In Press, 2015 | doi:10.2166/washdev.2015.119

Authors: V. Keshav, A. Mathee, N. Naicker, A. Swart and T. G. Barnard

E. coli is routinely used as an indicator of fecal pollution although some strains are capable of causing diarrhea. E. coli was used as a model organism for this study to assess the possibility that dishcloths used in households could contribute to the occurrence of diarrhea. Dishcloths (n = 424) were collected from five suburbs in Johannesburg (South Africa) as part of a larger Health, Environment & Development (HEAD) study. Results for the total coliforms indicated that on average 81% of the samples analyzed had total coliform counts of more than 1,000 cfu/100 ml per 25 cm2 cloth.

The E. coli results indicated that 40% of the samples had culturable E. coli present with 17% of the samples showing the presence of >1,000 cfu/100 ml per 25 cm2 cloth. Except for the samples from Bertrams all the pathogenic E. coli genes could be detected in various combinations in the different samples. Since all the diarrheagenic E. coli strains detected can be accepted as culturable due to the enrichment step, there is a clear danger of contamination of food and surfaces exposed to the contaminated dishcloths. The results indicated that there is a need for public education regarding hygiene in the households, especially if the same dishcloth is used for various tasks.