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With their numerous products and uses, multifunctional crops offer an attractive means for improving smallholder farmer livelihoods. This study applies a Life Cycle Sustainability Assessment (LCSA) to Moringa oleifera (moringa), a multifunctional crop with diverse applications in nutrition, cosmetics, and water treatment. The LCSA includes an Environmental Life Cycle Assessment (ELCA), Social Life Cycle Assessment (SLCA), and Life Cycle Costing (LCC). Surveys were conducted with 58 smallholder farmers and five moringa processors in Ghana. The ReCiPe 2016 Midpoint method was used for the ELCA. The 10-year Net Present Value (NPV) and Payback Period (PBP) were calculated for farmers and processors in the LCC. The SLCA focused on the Worker stakeholder category, particularly smallholder farmer impacts, including indicators for Next Generation Farming, Inclusiveness, Access to Services, Food Security, and Livelihood. A composite sustainability score was calculated from the ELCA, SLCA, and LCC results using the Characteristic Objects Method (COMET), a multi-criteria decision analysis method resistant to rank-reversal. The study compared five supply chains: leaf-only, leaf-and-seed, leaf-and-seed with seedcake reuse, seed-only, and seed-only with seedcake reuse. Environmental hotspots were identified in leaf and seed collection. Economically, leaf-only cultivation provided the highest 10-year NPV for farmers, while seed-only with seedcake reuse yielded the highest NPV for processors. The leaf-only supply chain had the best PBP for both farmers and processors. Socially, leaf-only cultivators outperformed reference points across all indicators, making it the most socially sustainable supply chain. Our findings highlight that improving market access, organizing seed cultivators into farmer-based groups, and optimizing farm gate product collection can enhance the sustainability of moringa supply chains, offering a model for other multifunctional crops in rural development. This study is the first to integrate LCSA with COMET, a promising approach that could be adopted in other sustainability assessment case studies. 

Household air pollution is a pervasive environmental health problem wherever access to cleaner fuels is poor. Despite numerous attempts to transition households away from polluting fuels, interventions are rarely sustainable. This intractability indicates that structural (i.e., systemic) dynamics act to maintain the status quo. In this case study of Ghana's Rural Liquefied Petroleum Gas (LPG) Promotion Program, our objectives were to 1) identify system structures affecting sustained fuel use, and 2) test strategies for improving intervention outcomes. To address these objectives, we applied a system dynamics approach, informed by a systematic literature review. A virtual simulation model was constructed to represent the implementation of the Rural LPG Program and its outcomes. By analyzing the model's structure and behavior, we proposed strategies that would improve the intervention's outcomes and tested the effectiveness of the strategies within the simulation model. Our results show that distributing two LPG cylinders to households (instead of one) contributed toward primary use of the fuel, whereas free weekly delivery of LPG (for up to four years) had limited long-term benefits and diminishing returns. Furthermore, reducing the time for users to perceive the benefits of cleaner fuels enhanced willingness-to-pay, and thereby helped to sustain higher rates of LPG use. This suggests that intervention planners should identify new users' expectations of benefits and proactively design ways to realize those benefits quickly (in a few weeks or less), while policy makers should support this as a design requirement in approval processes. 

In communities where people lack on-demand, safely managed drinking water, stored household water often becomes contaminated by fecal bacteria, regardless of the source-water quality. The objectives of this paper are to assess and control bacterial contamination in stored household water in Toamasina, a rapidly urbanizing city in eastern coastal Madagascar. We collected samples of source water and stored household water from 10 representative households that use different water sources and different storage strategies, and we analyzed the samples for several fecal indicator bacteria. We also tested three methods that residents of Toamasina could realistically employ for cleaning their household water storage vessels, assessing the effect of the cleaning methods on measured bacterial levels in the water. Consistent with the previous literature, we found that concentrations of total coliforms in stored household water were significantly higher than in the corresponding source water (p < 0.05). In 100% of households that stored their water in 20 L polyethylene jerrycans (n = 4), biofilms on the walls of the jerrycan harbored total coliforms and Enterococcus. The use of a closed storage container was, on its own, not found to provide a meaningful protective effect against bacterial regrowth; to be protective, closed storage containers must be combined with high-quality source water and/or with adequate cleaning to prevent biofilm formation. A dilute solution of sodium hypochlorite, known locally as Sûr’Eau or Manadio Rano, was both the most effective and the least expensive method for cleaning household water storage containers. We conclude that regular and effective cleaning of storage containers is an essential component of safe water storage. Because household storage of collected water is common in many low- and middle-income countries, these results are important towards the worldwide achievement of the United Nations’ Sustainable Development Goal 6. 

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. 

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. 

In 2021, Environmental Science & Technology convened an ACS Global Webinara on green stormwater infrastructure (GSI) as a tool for environmental justice. Since then, we researchers have continued to discuss advancing GSI science, practice, and priorities. The U.S. Environmental Protection Agency (1) describes green infrastructure as “the range of measures that use plant or soil systems, permeable pavement or other permeable surfaces or substrates, stormwater harvest and reuse, or landscaping to store, infiltrate, or evapotranspirate stormwater and reduce flows to sewer systems or to surface waters.” GSI systems use a variety of names both within the United States and worldwide (e.g., low-impact development, sponge cities, water sensitive cities) and encompasses concepts from physical stormwater design/management practices to sustainable urban planning and urban ecology. (2,3) GSI and, more broadly, other nature-based solutions offer possibilities for improving urban hydrologic function and water quality while providing multiple co-benefits; (4) however, we contend the most important benefit is as a tool to advance environmental justice (EJ). Indeed, if these benefits lack intentionality in process and placement to repair past harms, we miss the greatest opportunity of all. Here we present summarized thoughts concerning strengths, weaknesses and threats, and opportunities for GSI (Figure 1). 

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. 

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.