Establishing Solar Water Disinfection as a water treatment method at household level

In low income settlements where the quality of drinking water is highly contaminated due to poor hygienic practices at community and household levels, there is need for appropriate, simple, affordable and environmentally sustainable household water treatment technology. Solar water disinfection (SODIS) that utilizes both the thermal and ultra-violet effect of solar radiation to disinfect water can be used to treat small quantities of water at household level to improve its bacteriological quality for drinking purposes. This study investigated the efficacy of the SODIS treatment method in Uganda and determined the optimal condition for effective disinfection. Results of raw water samples from the study area showed deterioration in bacteriological quality of water moved from source to the household; from 3 to 36 cfu/100 mL for tap water and 75 to 126 cfu/100 mL for spring water, using thermotolerant coliforms (TTCs) as indicator microorganisms. SODIS experiments showed over 99.9% inactivation of TTCs in 6 h of exposure, with a threshold temperature of 39.5 ± 0.7°C at about 12:00 noon, in the sun during a clear sunny day. A mathematical optimal condition model for effective disinfection has been calibrated to predict the decline of the number of viable microorganisms over time.

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Erratum to Sustainability of novel water treatment technologies in developing countries: Lessons learned from research trials on a pilot continuous flow solar water disinfection system in rural Kenya [DEVENG 3 (2018) 47–59]

Development Engineering ◽

10.1016/j.deveng.2021.100083 ◽

2021 ◽

pp. 100083

Author(s):

Joanne Mac Mahon ◽

W.Gill Laurence

Keyword(s):

Developing Countries ◽

Water Treatment ◽

Continuous Flow ◽

Lessons Learned ◽

Water Disinfection ◽

Solar Water ◽

Solar Water Disinfection ◽

Treatment Technologies ◽

Rural Kenya

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Health gains from solar water disinfection (SODIS): evaluation of a water quality intervention in Yaoundé, Cameroon

Journal of Water and Health ◽

10.2166/wh.2010.003 ◽

2010 ◽

Vol 8 (4) ◽

pp. 779-796 ◽

Cited By ~ 22

Author(s):

Jürg Graf ◽

Serge Zebaze Togouet ◽

Norbert Kemka ◽

Domitille Niyitegeka ◽

Regula Meierhofer ◽

...

Keyword(s):

Water Quality ◽

Low Income ◽

Low Cost ◽

Intervention Group ◽

Water Disinfection ◽

Control Group ◽

Simple Method ◽

Household Level ◽

Solar Water ◽

Solar Water Disinfection

In developing countries, the burden of diarrhoea is still enormous. One way to reduce transmission of pathogens is by water quality interventions. Solar water disinfection (SODIS) is a low-cost and simple method to improve drinking water quality on household level. This paper evaluates the implementation of SODIS in slum areas of Yaoundé, Cameroon. Promoters trained 2,911 households in the use of SODIS. Two surveys with randomly selected households were conducted before (N = 2,193) and after (N = 783) the intervention. Using a questionnaire, interviewers collected information on the health status of children under five, on liquid consumption, hygiene and other issues. Prior to the intervention, diarrhoea prevalence amounted to 34.3% among children. After the intervention, it remained stable in the control group (31.8%) but dropped to 22.8% in the intervention group. Households fully complying with the intervention exhibited even less diarrhoea prevalence (18.3%) and diarrhoea risk could be reduced by 42.5%. Multivariate analyses revealed that the intervention effects are also observed when other diarrhoea risk factors, such as hygiene and cleanliness of household surroundings, are considered. According to the data, adoption of the method was associated with marital status. Findings suggest health benefits from SODIS use. Further promotional activities in low-income settings are recommended.

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Factors Affecting the Diffusion of Solar Water Disinfection: A Field Study in Bolivia

Health Education & Behavior ◽

10.1177/1090198108321248 ◽

2006 ◽

Vol 35 (4) ◽

pp. 541-560 ◽

Cited By ~ 28

Author(s):

Simone Heri ◽

Hans-Joachim Mosler

Keyword(s):

Low Cost ◽

Change Agents ◽

Water Disinfection ◽

Factors Affecting ◽

Household Level ◽

Solar Water ◽

The Social ◽

Solar Water Disinfection ◽

Broad Array ◽

Promotional Efforts

This study examines a broad array of theory-based factors derived from diffusion research that affect the current and intended use of solar water disinfection (SODIS), a simple, low-cost technology for treating drinking water at the household level. The perceived attributes of an innovation, the nature of the social system in which it is diffused, the extent of change agents' promotional efforts in diffusing it, and the nature of the communication channels used were operationalized by 16 variables. The aim of the study is to determine the influence of each factor and its predictive power. Eight areas in Bolivia were visited, and 644 families were interviewed on the basis of a structured questionnaire. Simultaneous multiple regression analysis showed that 9 of the 16 factors derived from diffusion research contributed significantly to predicting the current use of SODIS. The implications of the findings for customizing future SODIS diffusion activities are outlined.

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SODIS potential: A novel parameter to assess the suitability of solar water disinfection worldwide

Chemical Engineering Journal ◽

10.1016/j.cej.2021.129889 ◽

2021 ◽

Vol 419 ◽

pp. 129889

Author(s):

José Moreno-SanSegundo ◽

Stefanos Giannakis ◽

Sofia Samoili ◽

Giulio Farinelli ◽

Kevin G. McGuigan ◽

...

Keyword(s):

Water Disinfection ◽

Solar Water ◽

Solar Water Disinfection

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Solar water disinfection in high-volume containers: Are naturally occurring substances attenuating factors of radiation?

Chemical Engineering Journal ◽

10.1016/j.cej.2020.125852 ◽

2020 ◽

Vol 399 ◽

pp. 125852 ◽

Cited By ~ 2

Author(s):

Ángela García-Gil ◽

Rafael Valverde ◽

Rafael A. García-Muñoz ◽

Kevin G. McGuigan ◽

Javier Marugán

Keyword(s):

High Volume ◽

Water Disinfection ◽

Solar Water ◽

Naturally Occurring ◽

Solar Water Disinfection

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Excystation ofCryptosporidium parvumat temperatures that are reached during solar water disinfection

Parasitology ◽

10.1017/s0031182009005563 ◽

2009 ◽

Vol 136 (4) ◽

pp. 393-399 ◽

Cited By ~ 11

Author(s):

H. GÓMEZ-COUSO ◽

M. FONTÁN-SAINZ ◽

J. FERNÁNDEZ-ALONSO ◽

E. ARES-MAZÁS

Keyword(s):

Solar Radiation ◽

Cryptosporidium Parvum ◽

Gradual Increase ◽

Water Disinfection ◽

Waterborne Diseases ◽

Pathogenic Microorganisms ◽

Simple Method ◽

Solar Water ◽

Solar Water Disinfection ◽

Notable Increase

SUMMARYSpecies belonging to the generaCryptosporidiumare recognized as waterborne pathogens. Solar water disinfection (SODIS) is a simple method that involves the use of solar radiation to destroy pathogenic microorganisms that cause waterborne diseases. A notable increase in water temperature and the existence of a large number of empty or partially excysted (i.e. unviable) oocysts have been observed in previous SODIS studies with water experimentally contaminated withCryptosporidium parvumoocysts under field conditions. The aim of the present study was to evaluate the effect of the temperatures that can be reached during exposure of water samples to natural sunlight (37–50°C), on the excystation ofC. parvumin the absence of other stimuli. In samples exposed to 40–48°C, a gradual increase in the percentage of excystation was observed as the time of exposure increased and a maximum of 53·81% of excystation was obtained on exposure of the water to a temperature of 46°C for 12 h (versus8·80% initial isolate). Under such conditions, the oocyst infectivity evaluated in a neonatal murine model decreased statistically with respect to the initial isolate (19·38%versus100%). The results demonstrate the important effect of the temperature on the excystation ofC. parvumand therefore on its viability and infectivity.

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In vitro toxicity studies of novel solar water disinfection reactors using the E-screen bioassay and the Ames test

H2Open Journal ◽

10.2166/h2oj.2021.108 ◽

2021 ◽

Author(s):

Paloma Ozores Diez ◽

M. Inmaculada Polo-López ◽

Azahara Martínez-García ◽

Monique Waso ◽

Brandon Reyneke ◽

...

Keyword(s):

Ames Test ◽

Daily Intake ◽

Cost Effective ◽

Water Disinfection ◽

In Vitro Toxicity ◽

Toxic Substances ◽

Solar Water ◽

Point Of Use ◽

Solar Water Disinfection

Abstract Solar water disinfection (SODIS) is a cost-effective point of use method for disinfecting water, usually in a 2 L polyethylene terephthalate (PET) plastic bottle. To increase the volume of water disinfected, three novel transparent reactors were developed using PET in 25 L transparent jerrycans, polymethyl methacrylate (PMMA) in tubular solar reactors capable of delivering >20 L of water and polypropylene (PP) in 20 L buckets. In vitro bioassays were used to investigate any toxic substances leached from the plastic reactors into disinfected water as a result of exposure to sunshine for up to 9 months. The Ames test was used to test for mutagenicity and the E-screen bioassay to test for estrogenicity. No mutagenicity was detected in any sample and no estrogenicity was found in the SODIS treated water produced by the PMMA reactors or the PP buckets. While water disinfected using the PET reactors showed no estrogenicity following exposure to the sun for 3 and 6 months, estrogenicity was detected following 9 months' exposure to sunlight; however levels detected were within the acceptable daily intake for 17β-estradiol (E2) of up to 50 ng/kg body weight/day.

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