Wastewater in Latin American urban peripheries: Identifying research trends and challenges through a systematic literature review.

Water is a defining element for cities and their inhabitants. Throughout urban systems, water is either produced or received, used, and finally disposed of as wastewater. As Latin American urbanization accelerates, problems related to wastewater are increasing due to its inclusion as the main source of river pollution, as well as the high cost of infrastructure development and maintenance. The consequences of wastewater disposal are particularly relevant in areas frequently associated with urban expansion, like peripheries whose growth follows constant transitions between rural, peri-urban, and urban areas. Such consequences are often related to heterogeneity, lack of urban services and sanitation infrastructure, water pollution and health risks, as well as the development of informal compensatory systems. A systematic literature review was conducted to broaden research panorama and identify spatial, temporal, and thematic trends and challenges present in wastewater assessments of Latin American urban peripheries, this using the SALSA (search, appraisal, synthesis, and analysis) protocol in a search through international databases Scopus and Web of Science Scielo, in English, Spanish, French, and Portuguese. In these databases, 228 papers satisfied selection criteria and show a growing trend of publications about urban wastewater since 1988. Most case studies are from Brazil (58 %), Mexico (14 %), and Argentina (9 %). Their main approaches are quantitative research (82 %) in urban contexts (57 %). Most studies were found to be operationalized using environmental geochemistry methodologies, suggesting a dominance of technical, reductionist approaches. Integrated and mixed perspectives including actors and other societal elements are suggested as a central research challenge. Without an integrated view, it will be unfeasible to enhance decision-making processes and governance in the pursuit of sustainable water management.