Chlorine Water Taste Threshold and Acceptability among Indigenous and Non-Indigenous Populations in Rural Panama.

Although gains in access to water services over the past two decades have been large, more than two billion people still lack access to safely managed drinking water. This study examines and compares free chlorine taste and acceptability thresholds of rural Indigenous Ngäbe and rural Latino Panamanians to study if taste aversion may be a limiting factor in chlorination of community systems in Panama using the three-alternative forced choice test methodology. This study is the first to establish a best-estimate taste threshold for a rural Indigenous group and the only study in Latin America to report best-estimate taste thresholds using those methods. Median taste thresholds were 0.87 mg/L Cl2 for Indigenous Ngäbe participants (n = 82) and 1.64 mg/L Cl2 for Latino participants (n = 64), higher than both the minimum concentration for biologically safe water (0.2 mg/L) and the recommended concentration range in Panama (0.3-0.8 mg/L). Median acceptability thresholds were established much higher than taste thresholds at 3.45 mg/L Cl2. The results show that the ability to accurately taste chlorine may not be the limiting factor for adoption of safe water initiatives in remote and Indigenous communities.

Rural Sanitation Sustainability Dynamics: Gaining Insight through Participatory and Simulation Modeling.

Improved sanitation provides many benefits to human health and well-being and is integral to achieving Sustainable Development Goal Six. However, many nations, including most of sub-Saharan Africa, are not on track to meeting sanitation targets. Recognizing the inherent complexity of environmental health, we used systems thinking to study sanitation sustainability in Uganda. Our study participants, 37 sanitation actors in three rural districts, were engaged in interviews, group model building workshops, and a survey. The resulting model was parametrized and calibrated using publicly available data and data collected through the Uganda Sanitation for Health Activity. Our simulations revealed slippage from improved sanitation in all study districts, a behavior reflected in real interventions. This implies that systemic changes-changes to the rules and relationships in the system-may be required to improve sanitation outcomes in this context. Adding reinforcing feedback targeting households' perceived value of sanitation yielded promising simulation results. We conclude with the following general recommendations for those designing sanitation policies or interventions: (1) conceptualize sanitation systems in terms of reinforcing and balancing feedback, (2) consider using participatory and simulation modeling to build confidence in these conceptual models, and (3) design many experiments (e.g., simulation scenarios) to test and improve understanding.

Do Sanitation Marketing Activities Increase Households' Likelihoods of Reaching Improved Sanitation or Involving Women in Decision Making?

Poor sanitation causes 30% of diarrheal deaths globally, and much of the world has struggled to finance top-down interventions. Sanitation marketing is a demand-led approach that uses a mixture of social and commercial marketing methods and direct sales to households. However, little is known about its impacts on household decision making. This mixed-methods study uses data from eight focus groups and 86,666 household surveys from participants in a five-year sanitation marketing program in Uganda. Logistic regression models identified 10 variables predicting attainment of improved (limited or basic) sanitation and four variables predicting female involvement in decision making. Triggering session attendance increased chances of reaching improved sanitation by 15-28%, depending on who attended, and by 19% if the household found the session motivational. Although women were engaged in decision-making conversations, they were not viewed as primary decision makers, even in female-headed households. Women were more likely to become involved in decision making if they had attended triggering sessions with men (+70%) or engaged with sales promoters alone (+74%) or with men (+78%). For both outcomes, joint activity engagement was more effective than male or female engagement alone. This work highlights two sanitation marketing activities as pathways to improving latrine coverage and women's decision-making agency.

Reductions in Children's Blood Lead Levels from a Drinking-Water Intervention in Madagascar, Sub-Saharan Africa.

One in three children globally is estimated to have blood lead levels (BLL) at or above the BLL reference value of 5 µg/dL with increased burden falling on low- and middle-income countries (LMIC). Within developed countries, aqueous lead is the predominant exposure route. However, aqueous lead exposure is rarely examined in the LMIC, leaving a gap in the literature that ignores a potentially significant route of exposure. Furthermore, limited lead-based remediation efforts around consumer products have been examined. This study investigates the importance of lead exposure from the water supply through a case study in Toamasina, Madagascar. The project measured aqueous lead and BLL of children pre- and postremediation efforts (i.e., removal of leaded pump components in hand pumps) to verify the impact of aqueous lead exposure within this community. Removal of the leaded pump components (i.e., piston and foot valves) and replacement with nonleaded components decreased aqueous lead levels below the World Health Organization provisional guideline of 10 µg/L in all but 4% of pumps tested. Measured BLL concentrations indicated a statistically significant decrease in BLL from pre- to postremediation. Furthermore, the remediation resulted in a decrease in BLL for 87% of children with the greatest changes in BLL observed for children with the highest preremediation concentrations. These findings point to a need for greater consideration of lead in drinking and cooking waters as an important exposure route in LMIC.

Meeting the Water and Sanitation Challenges of Underbounded Communities in the U.S.

Water and sanitation (wastewater) infrastructure in the United States is aging and deteriorating, with massive underinvestment over the past several decades. For many years, lack of attention to water and sanitation infrastructure has combined with racial segregation and discrimination to produce uneven access to water and wastewater services resulting in growing threats to human and environmental health. In many metropolitan areas in the U.S., those that often suffer disproportionately are residents of low-income, minority communities located in urban disadvantaged unincorporated areas on the margins of major cities. Through the process of underbounding (the selective expansion of city boundaries to exclude certain neighborhoods often based on racial demographics or economics), residents of these communities are disallowed municipal citizenship and live without piped water, sewage lines, and adequate drainage or flood control. This Perspective identifies the range of water and sanitation challenges faced by residents in these communities. We argue that future investment in water and sanitation should prioritize these communities and that interventions need to be culturally context sensitive. As such, approaches to address these problems must not only be technical but also social and give attention to the unique geographic and political setting of local infrastructures.

Passive In-Line Chlorination for Drinking Water Disinfection: A Critical Review.

The world is not on track to meet Sustainable Development Goal 6.1 to provide universal access to safely managed drinking water by 2030. Removal of priority microbial contaminants by disinfection is one aspect of ensuring water is safely managed. Passive chlorination (also called in-line chlorination) represents one approach to disinfecting drinking water before or at the point of collection (POC), without requiring daily user input or electricity. In contrast to manual household chlorination methods typically implemented at the point of use (POU), passive chlorinators can reduce the user burden for chlorine dosing and enable treatment at scales ranging from communities to small municipalities. In this review, we synthesized evidence from 27 evaluations of passive chlorinators (in 19 articles, 3 NGO reports, and 5 theses) conducted across 16 countries in communities, schools, health care facilities, and refugee camps. Of the 27 passive chlorinators we identified, the majority (22/27) were solid tablet or granular chlorine dosers, and the remaining devices were liquid chlorine dosers. We identified the following research priorities to address existing barriers to scaled deployment of passive chlorinators: (i) strengthening local chlorine supply chains through decentralized liquid chlorine production, (ii) validating context-specific business models and financial sustainability, (iii) leveraging remote monitoring and sensing tools to monitor real-time chlorine levels and potential system failures, and (iv) designing handpump-compatible passive chlorinators to serve the many communities reliant on handpumps as a primary drinking water source. We also propose a set of reporting indicators for future studies to facilitate standardized evaluations of the technical performance and financial sustainability of passive chlorinators. In addition, we discuss the limitations of chlorine-based disinfection and recognize the importance of addressing chemical contamination in drinking water supplies. Passive chlorinators deployed and managed at-scale have the potential to elevate the quality of existing accessible and available water services to meet "safely managed" requirements.

Childhood blood lead levels and environmental risk factors in Madagascar.

One-third of children globally have blood lead levels (BLLs) exceeding the (former) US CDC reference value of 5 µg/dL; this value may be as high as one-half for children in low- and middle-income countries (LMICs). Lead exposure occurs through a variety of routes (e.g., water, dust, air), and in LMICs specifically, informal economies (e.g., battery recycling) can drive lead exposures due, in part, to absent regulation. Previous work by our team identified a ubiquitous source of lead (Pb), in the form of Pb-containing components used in manually operated pumps, in Toamasina, Madagascar. Characterization of BLLs of children exposed to this drinking water, and identification of additional exposure routes were needed. BLLs were measured for 362 children (aged 6 months to 6 years) in parallel with surveying to assess 14 risk factors related to demographics/socioeconomics, diet, use of pitcher pumps, and parental occupations. BLL data were also compared against a recent meta-review of BLLs for LMICs. Median childhood BLL (7.1 µg/dL) was consistent with those of other Sub-Saharan African LMICs (6.8 µg/dL) and generally higher than LMICs in other continents. Risk factors significantly associated (p < 0.05, univariate logistic regression) with elevated BLL (at ≥ 5 µg/dL) included male gender, living near a railway or major roadway (owing potentially to legacy lead pollution), having lower-cost flooring, daily consumption of foods (beans, vegetables, rice) commonly cooked in recycled aluminum pots (a previously identified lead source for this community), and a maternal occupation (laundry-person) associated with lower socioeconomic status (SES). Findings were similar at the ≥ 10 µg/dL BLL status. Our methods and findings may be appropriate in identifying and reducing lead exposures for children in other urbanizing cities, particularly in Sub-Saharan Africa, where lead exposure routes are complex and varied owing to informal economics and substantial legacy pollution.

Systems Thinking for Effective Interventions in Global Environmental Health.

Environmental health risks such as household air pollution due to burning solid fuels, inadequate water, sanitation, and hygiene, and chemical pollution disproportionately affect the poorest and most marginalized populations. While billions of dollars and countless hours of research have been applied toward addressing these issues in both development and humanitarian contexts, many interventions fail to achieve or sustain desired outcomes over time. This pattern points to the perpetuation of linear thinking, despite the complex nature of environmental health within these contexts. There is a need and an opportunity to engage in critical reflection of the dominant paradigms in the global environmental health community, including how they affect decision-making and collective learning. These paradigms should be adapted as needed toward the integration of diverse perspectives and the uptake of systems thinking. Participatory modeling, complexity-aware monitoring, and virtual simulation modeling can help achieve this. Additionally, virtual simulation modeling is relatively inexpensive and can provide a low-stakes environment for testing interventions before implementation.

A systems approach to analyzing food, energy, and water uses of a multifunctional crop: A review.

Multifunctional crops can simultaneously contribute to multiple societal objectives. As a result, they represent an attractive means for improving rural livelihoods. Moringa oleifera is an example of a multifunctional crop that produces nutritious leaves with uses as food, fodder, and a biostimulant to enhance crop growth. It yields seeds containing a water purifying coagulant and oil with cosmetic uses and possible biofuel feedstock. Despite Moringa oleifera's (and other multifunctional crops') various Food-Energy-Water uses, optimizing the benefits of its multiple uses and livelihood improvements remains challenging. There is a need for holistic approaches capable of assessing the multifunctionality of agriculture and livelihood impacts. Therefore, this paper critically evaluates Moringa oleifera's Food-Energy-Water-Livelihood nexus applications to gain insight into the tradeoffs and synergies among its various applications using a systems thinking approach. A systems approach is proposed as a holistic thinking framework that can help navigate the complexity of a crop's multifunctionality. The "Success to the Successful" systems archetype was adopted to capture the competition between the need for leaf yields and seed yields. In areas where there is energy and water insecurity, Moringa oleifera seed production is recommended for its potential to coproduce oil, the water purifying coagulant, and a residue that can be applied as a fertilizer. In areas where food insecurity is an issue, focusing on leaf production would be beneficial due to its significance in augmenting food for human consumption, animal feed, and its use as a biostimulant to increase crop yields. A causal loop diagram was found to effectively map the interconnections among the various uses of Moringa oleifera and associated livelihood improvements. This framework provides stakeholders with a conceptual decision-making tool that can help maximize positive livelihood outcomes. This approach can also be applied for improved management of other multifunctional crops.

Midstream Players Determine Population-Level Behavior Change: Social Marketing Research to Increase Demand for Lead-Free Components in Pitcher Pumps in Madagascar.

Lead (Pb) exposure through water contamination is an important issue at the intersection of public health and water, sanitation, and hygiene (WASH). Behavior-change programs designed to address this pressing problem rarely take a behavioral-science-informed approach, nor do they consider the role of intermediate players who often influence and support behavior change. Social marketing segments the population and focuses on the consumer/user throughout program development and implementation. To illustrate the social marketing process, this cross-sectional, qualitative design study investigates the use of Pb in the construction and maintenance of household pitcher pumps for potable water in Madagascar. A sample of 18 technicians were interviewed on their current practices, motivators, barriers, and communication channels for knowledge exchange. The results reveal the importance of peers, those considered experts or "market mavens", and the need for information on the dangers of Pb as an outdated practice for any future intervention. This study advances the notion of a design shift within engineering WASH projects, whereby social/behavioral approaches are used to consider the needs, concerns, and current behaviors of the consumer. We also advocate for engaging intermediate players who often influence behavior change in the rollout of an engineering innovation.

Health and Economic Consequences of Lead Exposure Associated with Products and Services Provided by the Informal Economy.

In low- and middle-income countries (LMICs), the presence of an informal economy can lead to human exposure to toxic metals such as lead (Pb). This paper demonstrates the local health and economic benefits of modifying practices within the informal economic sector in Madagascar. Specifically, leaded components in 504 locally manufactured household water pumps were replaced with unleaded components. Prior to the intervention, 32% of the household systems exhibited lead concentrations above the World Health Organization (WHO) provisional drinking water guideline of 10 µg/L, but after the intervention, fewer than 3% of the systems were in exceedance. The reduction of lead concentration is modeled to reduce the fraction of children with elevated BLLs (>5 µg/dL) from 34 to 13%. The reduction in BLLs is estimated to provide an average economic benefit of US$11 800 per child based on predicted increases in lifetime productivity. This corresponds to a total benefit of US$8.7 million for the 730 children aged 1-5 associated with the pumps, representing a return on investment of greater than 1000-to-1. Results demonstrate how the formation of partnerships between public, private, and civil society entities, as suggested by UN Sustainable Development Goal 17, can realize important local economic and health benefits in LMICs.

Attitudes of food consumers at universities towards recycling human urine as crop fertiliser: A multinational survey dataset.

We present here a data set generated from a multinational survey on opinions of university community members on the prospect of consuming food grown with human urine as fertiliser and about their urine recycling perceptions in general. The data set comprises answers from 3,763 university community members (students, faculty/researchers, and staff) from 20 universities in 16 countries and includes demographic variables (age bracket, gender, type of settlement of origin, academic discipline, and role in the university). Questions were designed based on Ajzen's theory of planned behaviour to elicit information about three components of behavioural intention-attitudes, subjective norms, and perceived behavioural control. Survey questions covered perceived risks and benefits (attitudes), perceptions of colleagues (injunctive social norm) and willingness to consume food grown with cow urine/faeces (descriptive social norm), and willingness to pay a price premium for food grown with human urine as fertiliser (perceived behavioural control). We also included a question about acceptable urine recycling and disposal options and assessed general environmental outlook via the 15-item revised New Ecological Paradigm (NEP) scale. Data were collected through a standardised survey instrument translated into the relevant languages and then administered via an online form. Invitations to the survey were sent by email to university mailing lists or to a systematic sample of the university directory. Only a few studies on attitudes towards using human urine as fertiliser have been conducted previously. The data described here, which we analysed in "Willingness among food consumers at universities to recycle human urine as crop fertiliser: Evidence from a multinational survey" [1], may be used to further understand potential barriers to acceptance of new sanitation systems based on wastewater source separation and urine recycling and can help inform the design of future sociological studies.

Willingness among food consumers to recycle human urine as crop fertiliser: Evidence from a multinational survey.

Source-separating sanitation systems offer the possibility of recycling nutrients present in wastewater as crop fertilisers. Thereby, they can reduce agriculture's impacts on global sources, sinks, and cycles for nitrogen and phosphorous, as well as their associated environmental costs. However, it has been broadly assumed that people would be reluctant to perform the new sanitation behaviours that are necessary for implementing such systems in practice. Yet, few studies have tried to systematically gather evidence in support of this assumption. To address this gap, we surveyed 3763 people at 20 universities in 16 countries using a standardised questionnaire. We identified and systematically assessed cross-cultural and country-level explanatory factors that were strongly associated with people's willingness to consume food grown using human urine as fertiliser. Overall, 68% of the respondents favoured recycling human urine, 59% stated a willingness to eat urine-fertilised food, and only 11% believed that urine posed health risks that could not be mitigated by treatment. Most people did not expect to pay less for urine-fertilised food, but only 15% were willing to pay a price premium. Consumer perceptions were found to differ greatly by country and the strongest predictive factors for acceptance overall were cognitive factors (perceptions of risks and benefits) and social norms. Increasing awareness and building trust among consumers about the effectiveness of new sanitation systems via cognitive and normative messaging can help increase acceptance. Based on our findings, we believe that in many countries, acceptance by food consumers will not be the major social barrier to closing the loop on human urine. That a potential market exists for urine-fertilised food, however, needs to be communicated to other stakeholders in the sanitation service chain.