Evaluation of a new water treatment for point-of-use household applications to remove microorganisms and arsenic from drinking water

Abstract

Contamination of drinking water by microorganisms and arsenic represents a major human health hazard in many parts of the world. An estimated 3.4 million deaths a year are attributable to waterborne diseases. Arsenic poisoning from contaminated water sources is causing a major health emergency in some countries such as Bangladesh where 35 to 77 million people are at risk. The World Health Organization (WHO) has recently recognized point-of-use water treatment as an effective means of reducing illness in developing country households. A new point-of-use water treatment system that is based on flocculation, sedimentation and disinfection was evaluated for the removal of bacterial, viral and parasitic pathogens as well as arsenic from drinking water to estimate its potential for use in developing countries. Tests were conducted with United States Environmental Protection Agency (EPA)-model and field- sample waters from developing countries. Samples were seeded with known numbers of organisms, treated with the combined flocculation/disinfection product, and assayed for survivors using standard assay techniques appropriate for the organism. Results indicated that this treatment system reduced the levels from 10(8)/l to undetectable (<1) of 14 types of representative waterborne bacterial pathogens including Salmonella typhi and Vibrio cholerae. No Escherichia coli were detected post-treatment in 320 field water samples collected from five developing countries. In addition, the water treatment system reduced polio and rotavirus titres by greater than 4-log values. Cyrptosporidium parvum and Giardia lamblia inocula were reduced by greater than 3-log values following use of this water treatment system. Arsenic, added to laboratory test waters, was reduced by 99.8%, and naturally occurring arsenic in field samples from highly contaminated Bangladeshi wells was reduced by 99.5% to mean levels of 1.2 microg/l. This water treatment system has demonstrated the potential to provide improved drinking water to households in developing countries by removing microbial and arsenic contaminants.

Effects of Temperature and pH on Reduction of Bacteria in a Point-of-Use Drinking Water Treatment Product for Emergency Relief

“…Under reference conditions, its performance was comparable to that reported previously (6)(7)(8). Any differences could be attributed to the choice of a thinner filtration material used in this study.…”

User preferences and willingness to pay for safe drinking water: Experimental evidence from rural Tanzania

“…The durables were ceramic pot filters (Safe Water Now, n.d.), and ceramic siphon filters (Basic Water Needs India Pvt Ltd, n. d.-a). All these options significantly reduce E. coli concentrations in the laboratory (LeChevallier and Au, 2004;Brown and Sobsey, 2010;Basic Water Needs India Pvt Ltd, n. d.-b), and in the field (Mohamed et al, 2015;Clasen et al, 2007;Souter et al, 2003;Ziff, 2008;Brown et al, 2008). Boiling served as a comparison for the HWTS retail products; it has been shown to significantly reduce E. coli in field conditions (Brown and Sobsey, 2012).…”

Reducing diarrhoea in Guatemalan children: randomized controlled trial of flocculant-disinfectant for drinking water

“…The flocculant-disinfectant includes many chemicals used in commercial water treatment but has been specially formulated to work quickly on small volumes of water. 11 All ingredients in the flocculant-disinfectant are used in commercial water treatment or in food products and are generally recognized as safe. The flocculant-disinfectant combines precipitation, coagulation and flocculation with chlorination.…”

“…An in-home water treatment product has been developed to address these issues. 11 The technology consists of…”