Assessment of the 20L SODIS bucket household water treatment technology under field conditions in rural Malawi.

Two billion people worldwide consume unsafe drinking water. The problem is particularly pronounced in Sub-Saharan Africa, where more than a quarter of the population relies on unimproved surface water sources. Based on the principles of solar water disinfection (SODIS), a new household water treatment technology, the SODIS bucket, was developed to improve the microbial quality of water from these sources based on controlled tests in a laboratory setting. This study set out to evaluate the efficacy of the technology in a field setting, in rural communities in the Chikwawa District in southern Malawi. SODIS experiments were carried out in two different vessels (1-L PET bottles and 20-L polypropylene SODIS buckets), over three months using unprotected water sources normally used by community members. Vessels were exposed to direct sunlight for 8 h per day in a village setting and were sampled at regular intervals to determine total coliforms, E. coli, turbidity, UV transmittance and UV dose. In these experiments, the SODIS bucket reached inactivation targets for E. coli (<1 CFU/100 mL) in two of seven experiments and for total coliforms in one of seven for total coliforms (<50 CFU/100 mL), despite having greater UV doses than were seen in the evaluation carried out under controlled conditions during the bucket's development. PET bottles reached inactivation targets for both E. coli and total coliforms in five of seven experiments. There was no single factor that could be identified as preventing adequate inactivation, but the role of organic matter, inconsistent nature of the water source, and vessel size, when coupled with organic matter, were identified as contributing factors. This study highlights the need for further prototyping to provide a suitable pre-treatment step for unprotected water sources, and the importance of field testing with real-life parameters to ensure new technologies are context appropriate.

Perceptions of Inclusivity and Sustainability in Urban Sanitation in Global South Cities.

Citywide Inclusive Sanitation (CWIS) calls for sustainable urban sanitation services for all, but the definitions of "inclusion" and "sustainability" within the framework leave room for interpretation. This study aims to provide an initial understanding of how these terms are currently interpreted by a range of sanitation actors in six cities of the Global South. Urban sanitation professionals from private (n = 16), public (n = 28), non-governmental (n = 43), and academic (n = 10) institutions were interviewed using a standardized tool, and data was analyzed to identify themes and trends. Terms such as "everyone" or "for all" shed little light on how to ensure inclusion, though disabled people, women, children, and the poor were all highlighted when probed. Greater specificity of beneficiary groups in policy is likely to enhance their visibility within sanitation service provision. All three pillars of sustainability identified within CWIS were referenced, with different stakeholders focusing more closely on environmental, social, or economic sustainability, based on their organizational goals and interests. Greater collaboration may foster a balanced view across the pillars, with different organizations acting as champions for each one. The findings can facilitate discussions on a shared understanding of multi-stakeholder engagement in achieving inclusive and sustainable sanitation service provision.

Exposure to Air Pollution in Rural Malawi: Impact of Cooking Methods on Blood Pressure and Peak Expiratory Flow.

We made static and personal PM2.5 measurements with a miniature monitor (RTI MicroPEM) to characterise the exposure of women cooking with wood and charcoal in indoor and outdoor locations in rural Malawi, together with measurements of blood pressure and peak expiratory flow rate (PEFR). Mean PM2.5 concentrations of 1338 and 31 µg/m3 were observed 1 m from cookstove locations during cooking with wood and charcoal, respectively. Similarly, mean personal PM2.5 exposures of 706 and 94 µg/m3 were observed during cooking with wood and charcoal, respectively. Personal exposures to PM2.5 in indoor locations were 3.3 and 1.7 times greater than exposures observed in equivalent outdoor locations for wood and charcoal, respectively. Prior to the measured exposure, six out of eight participants had PEFR observations below 80% of their expected (age and height) standardised PEFR. We observed reductions in PEFR for participants cooking with wood in indoor locations. Five out of eight participants reported breathing difficulties, coughing, and eye irritation when cooking with wood but reported that symptoms were less severe when cooking with charcoal. In conclusion, we observed that exposure to PM2.5 was substantially reduced by cooking outdoor with charcoal. As both wood and charcoal fuels are associated with negative environmental and health impacts, the adoption of high-efficiency cookstoves and less polluting sources of energy will be highly beneficial. Cooking outside whenever possible, and minimising the time spent in close proximity to stoves, may be simple interventions that could reduce the risks of exacerbation and progression of respiratory and cardiovascular diseases in Malawi.

A Transdisciplinary Methodology for Introducing Solar Water Disinfection to Rural Communities in Malawi-Formative Research Findings.

Despite the increasing volume of evidence demonstrating the efficacy of solar water disinfection (SODIS) as a household water treatment technology, there still appear to be significant barriers to uptake in developing countries. The potential of SODIS is often treated with skepticism in terms of effective treatment, volume, and safety, and is dismissed in preference for more accepted technologies such as ceramic filters and dose chlorination. As part of WATERSPOUTT (EU H2020 688928), our study used a transdisciplinary methodology to cocreate an innovative SODIS system in rural Malawi. The formative work focused on the design of 1) an appropriate and acceptable system and 2) a context-specific intervention delivery program using a behavior-centered design. Initial research identified specific water needs and challenges, which were discussed along with a cocreation process with potential end users, through a series of shared dialogue workshops (SDWs). Specifications from end users outlined a desire for higher volume systems (20 L) that were "familiar" and could be manufactured locally. Development of the "SODIS bucket" was then undertaken by design experts and local manufacturers, with input from end users and subject to controlled testing to ensure efficacy and safety. Concurrent data were collated using questionnaires (n = 777 households), water point mapping (n = 121), water quality testing (n = 46), and behavior change modeling (n = 100 households). These identified specific contextual issues (hydrogeology, water access, gender roles, social capital, and socioeconomic status), and behavioral determinants (normative, ability, and self-regulation factors) that informed the development and delivery mechanism for the implementation toolkit. Integr Environ Assess Manag 2020;16:871-884. © 2020 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals, Inc. on behalf of Society of Environmental Toxicology & Chemistry (SETAC).