The use of indigenous plant species for drinking water treatment in developing countries: a review. Journal of Biodiversity and Environmental Sciences (JBES), Sept 2014.

Moa Megersa, Abebe Beyene, Argaw Ambelu, Bizuneh Woldeab. Department of Environmental Health Science and Technology, Jimma University, Jimma, Ethiopia

Although universal access to safe and piped water is an important long-term solution, it is very expensive and challenging to implement in developing countries in the short term. Hence, improving both physicochemical and microbiological quality of drinking water at a household level is believed to be effective in preventing infectious diarrhea. There are a number of household water treatment technologies proven to be effective in coagulation and disinfection. At present, a number of effective coagulants and disinfectants have been identified of plant origin.

Of the large number of plant materials that have been used over the years, the seeds from Moringa oleifera have been shown to be one of the most effective primary coagulants for water treatment, especially in ruralcommunities. In addition, indigenous knowledge indicates that there are several plant species that can be used as a coagulant and disinfectant. Out of which seeds of Prosopis juliflora, Dolichos lablab and leaves of Opuntia ficus indica showed effectiveness in coagulation. Although, plant species have enormous advantage in water treatment, they also have limitation. The major limitation is the release of organic matter and nutrients to apply at large scale. From these review, it can be concluded that plant species have the potential to serve as a complementary water treatment agent especially in rural areas.

Coliform Bacteria as Indicators of Diarrheal Risk in Household Drinking Water: Systematic Review and Meta-Analysis. PLoS ONE, Sept 2014.

Authors: Joshua S. Gruber, Ayse Ercumen, John M. Colford Jr.

Background – Current guidelines recommend the use of Escherichia coli (EC) or thermotolerant (“fecal”) coliforms (FC) as indicators of fecal contamination in drinking water. Despite their broad use as measures of water quality, there remains limited evidence for an association between EC or FC and diarrheal illness: a previous review found no evidence for a link between diarrhea and these indicators in household drinking water.

Objectives – We conducted a systematic review and meta-analysis to update the results of the previous review with newly available evidence, to explore differences between EC and FC indicators, and to assess the quality of available evidence.

Methods – We searched major databases using broad terms for household water quality and diarrhea. We extracted study characteristics and relative risks (RR) from relevant studies. We pooled RRs using random effects models with inverse variance weighting, and used standard methods to evaluate heterogeneity and publication bias.

Results – We identified 20 relevant studies; 14 studies provided extractable results for meta-analysis. When combining all studies, we found no association between EC or FC and diarrhea (RR 1.26 [95% CI: 0.98, 1.63]). When analyzing EC and FC separately, we found evidence for an association between diarrhea and EC (RR: 1.54 [95% CI: 1.37, 1.74]) but not FC (RR: 1.07 [95% CI: 0.79, 1.45]). Across all studies, we identified several elements of study design and reporting (e.g., timing of outcome and exposure measurement, accounting for correlated outcomes) that could be improved upon in future studies that evaluate the association between drinking water contamination and health.

Conclusions – Our findings, based on a review of the published literature, suggest that these two coliform groups have different associations with diarrhea in household drinking water. Our results support the use of EC as a fecal indicator in household drinking water.

Synthetic organic water contaminants in developing communities: an overlooked challenge addressed by adsorption with locally generated char. Journal of Water, Sanitation and Hygiene for Development, Vol 4 No 3 pp 422–436 © IWA Publishing 2014 doi:10.2166/washdev.2014.073

Joshua P. Kearns, Detlef R. U. Knappe and R. Scott Summers

Department of Civil, Environmental, & Architectural Engineering, University of Colorado-Boulder, 1111 Engineering Dr, ECOT 441, UCB 428, Boulder, CO 80309, USA E-mail: joshua.kearns@colorado.edu
Department of Civil, Construction, & Environmental Engineering, North Carolina State University, 2501 Stinson Dr, Campus Box 7908, Raleigh, NC 27695, USA

Chemical contamination of drinking water sources is a worldwide problem. However, few locally managed, sustainable, and low-cost on-site treatment technologies are available in rural, remote, and emergency/disaster relief/humanitarian crisis situations. Char filter-adsorbers have been used to treat drinking water for thousands of years and are still widely used today. Our studies show that some chars produced by traditional means from a range of feedstocks develop favorable sorption properties for uptake of 2,4-dichlorophenoxyacetic acid (2,4-D), a prevalent herbicide and water contaminant.

However, more energy efficient, environmentally sustainable and scalable production of consistent highly sorptive chars can be accomplished with biomass gasification. Our laboratory studies demonstrate that locally produced char adsorbents derived from surplus agricultural and forestry biomass are effective for adsorbing 2,4-D. A year-long study of field-scale application of chars in Thailand is also presented. Based on these studies we present design recommendations for integrating char adsorbers into low-cost, multi-barrier treatment trains for on-site water provision.

A compact point-of-use water purification cartridge for household use in developing countries. Journal of Water and Health, In Press, Uncorrected Proof © IWA Publishing 2014 | doi:10.2166/wh.2014.111

Rajshree A. Patil, Dilshad Ahmad, Shankar B. Kausley, Pradeep L. Balkunde and Chetan P. Malhotra

TCS Innovation Labs – TRDDC, 54B, Hadapsar Industrial Estate, Pune – 411013, India E-mail: rajshree.patil@tcs.com

Simple, low-cost household interventions are known to be effective in lowering the incidence of waterborne diseases in developing countries. However, high costs along with operational and maintenance issues have prevented the successful adoption of these interventions among the affected communities. To address these limitations, a cost-effective, gravity-driven water purification cartridge has been developed by employing the synergistic disinfection action of low concentrations of silver and chlorine on bacteria and viruses.

The silver and chlorine treatment components within the cartridge have been developed using inexpensive materials and integrated with a life indicator and auto-shut-off-mechanism within a compact form factor. The antibacterial as well as antiviral performance of the cartridge was tested by using ground water spiked with Escherichia coli and MS2 bacteriophage. The results show that, although individually, the silver and chlorine treatment systems were unable to inactivate the test strains, the integrated cartridge inactivates both bacteria as well as viruses up to the log reduction requirement of the USEPA guide standard for microbiological water purifiers over its designated life of 2,000 liters.

Factors involved in sustained use of point-of-use water disinfection methods: A field study from Flores Island, Indonesia. Journal of Water and Health, In Press, Uncorrected Proof © IWA Publishing 2014 | doi:10.2166/wh.2014.109

E. Roma, T. Bond and P. Jeffrey
Cranfield University, Water Science Institute, Cranfield, MK430AL, UK E-mail: elisa.roma@lshtm.ac.uk
Environmental Health Group, London School of Hygiene and Tropical Medicine, WC17HT, London, UK
Civil and Environmental Engineering, Skempton Building, Imperial College, London, UK

Many scientific studies have suggested that point-of-use water treatment can improve water quality and reduce the risk of infectious diseases. Despite the ease of use and relatively low cost of such methods, experience shows the potential benefits derived from provision of such systems depend on recipients’ acceptance of the technology and its sustained use. To date, few contributions have addressed the problem of user experience in the post-implementation phase.

This can diagnose challenges, which undermine system longevity and its sustained use. A qualitative evaluation of two household water treatment systems, solar disinfection (SODIS) and chlorine tablets (Aquatabs), in three villages was conducted by using a diagnostic tool focusing on technology performance and experience. Cross-sectional surveys and in-depth interviews were used to investigate perceptions of involved stakeholders (users, implementers and local government).

Results prove that economic and functional factors were significant in using SODIS, whilst perceptions of economic, taste and odour components were important in Aquatabs use. Conclusions relate to closing the gap between factors that technology implementers and users perceive as key to the sustained deployment of point-of-use disinfection technologies.

Strategies for building resilience to hazards in water, sanitation and hygiene (WASH) systems: The role of public private partnerships. International Journal of Disaster Risk Reduction, 15 July 2014.

Authors: Ase Johannessen, Arno Rosemarin, Frank Thomall, Asa Gerger Swartling, Thor Axel Stenström, Gregor Vulturius.

The aim of this paper is to enhance understanding of how the resilience of water, sanitation and hygiene (WASH) systems to hazards can be improved. In turn, this aims to inform different strategies for public and private partnerships (PPPs). In a new approach, to acknowledge the multi levelled nature of resilience; risk at the relevant levels are taken into account, (regional/river basin, urban area, and individual). For these levels, we first describe the different components of risk, vulnerability and resilience of the WASH system that influence people׳s exposure to hazards. We illustrate these components using examples from case studies in the literature.

Using a social learning lens – a crucial ingredient of resilience – we examine opportunities for reducing risks through improving public–private engagement. These are presented as strategies which could guide investment decisions: As pressures from climate change and development add up, businesses must become aware of the risks involved in operating and investing without considering ecosystem health, both in terms of the services they provide for mitigating floods and droughts, as well as in terms of the development approaches that define how ecosystems are managed (e.g. “making space” for, rather than controlling water). There is a need to develop an institutional culture that strives towards greener and more resilient urban environments with the help of various quality assurance methods. Partnerships must reach the poorer customer base, encourage informal small entrepreneurs, and boost financial mechanisms (e.g. micro-insurance, micro-finance) to support the most vulnerable in society.

 

The effect of increasing grain size in biosand water filters in combination with ultraviolet disinfection. Journal of Water, Sanitation and Hygiene for Development, Vol 4 No 2 pp 206–213

This paper is in the public domain: verbatim copying and redistribution of this paper are permitted in all media for any purpose, provided this notice is preserved along with the paper’s original DOI. Anyone using the paper is requested to properly cite and acknowledge the source as Journal of Water, Sanitation and Hygiene for Development 4(2), 206–213. doi:10.2166/washdev.2013.171

Authors: Timothy E. Frank, Matthew L. Scheie, Victoria Cachro and Andrew S. Muñoz
2354 Fairchild Drive Suite 6J-117, USAF Academy, CO 80840, 01-719-660-6903, USA E-mail: tefrank18@gmail.com

With sand less than 0.70 mm often difficult to source in the field, it is of interest to study larger grained sand for use in biosand water filters (BSF). This study examined how sand grain size affects biological sand water filtration and how the combination of biological sand filtration and ultraviolet (UV) disinfection affects drinking water quality. Two BSFs were built: a control with maximum grain size, dmax = 0.70 mm and an experimental with grain sizes ranging from 0.70 mm to dmax = 2.0 mm. Untreated water was passed through each BSF daily. Results show Escherichia coli and turbidity removal characteristics of the control and experimental BSFs were not significantly different from one another. Both BSFs produced water that met World Health Organization (WHO) drinking water guidelines for turbidity, and although E. coli reduction was over 98% for each BSF, a high initial bacteria concentration resulted in effluent levels above WHO guidelines. Subsequently, effluent from each BSF was placed in clear plastic bottles under UV light, after which water from each BSF met E. coli guidelines. The data yielded promising results for using larger sand in BSFs, but longer duration studies with more data points are needed.

Where There Is No Toilet: Water and Sanitation Environments of Domestic and Facility Births in Tanzania. PLoS One, Sep 2014.

Authors: Lenka Benova, Oliver Cumming, Bruce A. Gordon, Moke Magoma, Oona M. R. Campbell

Background – Inadequate water and sanitation during childbirth are likely to lead to poor maternal and newborn outcomes. This paper uses existing data sources to assess the water and sanitation (WATSAN) environment surrounding births in Tanzania in order to interrogate whether such estimates could be useful for guiding research, policy and monitoring initiatives.

Methods – We used the most recent Tanzania Demographic and Health Survey (DHS) to characterise the delivery location of births occurring between 2005 and 2010. Births occurring in domestic environments were characterised as WATSAN-safe if the home fulfilled international definitions of improved water and improved sanitation access. We used the 2006 Service Provision Assessment survey to characterise the WATSAN environment of facilities that conduct deliveries. We combined estimates from both surveys to describe the proportion of all births occurring in WATSAN-safe environments and conducted an equity analysis based on DHS wealth quintiles and eight geographic zones.

Results – 42.9% (95% confidence interval: 41.6%–44.2%) of all births occurred in the woman’s home. Among these, only 1.5% (95% confidence interval: 1.2%–2.0%) were estimated to have taken place in WATSAN-safe conditions. 74% of all health facilities conducted deliveries. Among these, only 44% of facilities overall and 24% of facility delivery rooms were WATSAN-safe. Combining the estimates, we showed that 30.5% of all births in Tanzania took place in a WATSAN-safe environment (range of uncertainty 25%–42%). Large wealth-based inequalities existed in the proportion of births occurring in domestic environments based on wealth quintile and geographical zone.

Conclusion – Existing data sources can be useful in national monitoring and prioritisation of interventions to improve poor WATSAN environments during childbirth. However, a better conceptual understanding of potentially harmful exposures and better data are needed in order to devise and apply more empirical definitions of WATSAN-safe environments, both at home and in facilities.

Cholera at the Crossroads: The Association Between Endemic Cholera and National Access to Improved Water Sources and Sanitation. Am J Trop Med Hyg. 2014 Sep 8. pii: 14-0331.

Authors: Nygren BL1, Blackstock AJ2, Mintz ED2. 1Division of Foodborne, Waterborne and Environmental Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia bnygren@cdc.gov.
2Division of Foodborne, Waterborne and Environmental Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia.

We evaluated World Health Organization (WHO) national water and sanitation coverage levels and the infant mortality rate as predictors of endemic cholera in the 5-year period following water and sanitation coverage estimates using logistic regression, receiver operator characteristic curves, and different definitions of endemicity. Each was a significant predictors of endemic cholera at P < 0.001. Using a value of 250 for annual cases reported in 3 of 5 years, a national water access level of 71% has 65% sensitivity and 65% specificity in predicting endemic cholera, a sanitation access level of 39% has 63% sensitivity and 62% specificity, and an infant mortality rate of 65/1,000 has 67% sensitivity and 69% specificity. Our findings reveal the trade off between sensitivity and specificity for these predictors of endemic cholera and highlight the substantial uncertainty in the data. More accurate global surveillance data will enable more precise characterization of the benefits of improved water and sanitation.

Researchers create novel water purifying filter – Source: SciDevNet, Aug 25, 2014

[CAPE TOWN] A team of researchers have developed a membrane-based water filter that can provide up to 300 litres of clean drinking water.

The WHO says about 780 million people worldwide, especially those in Sub-Saharan Africa, lack access to improved water source.

The researchers from the Swiss Federal Institute of Technology in Zurich (ETHZ) in Switzerland announced last month (22 July) that DrinkPure filter, which they have developed, is based on a simple screw-top design that fits onto any plastic bottle.

Wendelin Stark, a professor of functional materials engineering at ETHZ, who helped create the innovation, says: “It requires no manual, no electricity, and no additional tools or training needs. You simply screw it on, and you drink [the water].”

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