Health risk assessment along wastewater recovery and reuse systems in Kampala, Uganda and Hanoi, Vietnam

Abstract

Background: Reuse and recovery of wastewater in agriculture and aquaculture has gained traction in the new millennium. In view of continued population growth, increasing scarcity of freshwater and other natural resources, the demand to boost food production and efforts to enhance wastewater reuse will increase in the years to come. Indeed, wastewater reuse and the recovery of water, nutrients and energy can generate promising business opportunities and support livelihoods in poor communities, particularly in urban and peri-urban areas of low- and middle-income countries (LMICs). Contact with untreated wastewater is associated with microbial and chemical hazards and thus might negatively affect human health. Standardised, quality-controlled methods to assess and manage health risks are available, such as those described in the World Health Organization (WHO) guidelines for the safe use of wastewater, excreta and greywater. However, the practicability and uptake of these methods have proved difficult in LMICs. There is a paucity of context-specific, quality-based environmental pollution data, epidemiological data and accurate disease burden estimates for highly dynamic environments along wastewater recovery and reuse systems in major urban settings, especially in Africa, Asia and Latin America. Moreover, discharge thresholds and health-based targets need to be reviewed to match the realities of LMICs. Objectives: This PhD thesis aims to generate evidence of health risks among people living and working along wastewater and faecal sludge management and reuse systems in Kampala, Uganda, a low-income African city, and in Hanoi, Vietnam, a lower-middle-income Asian city. By comparing relevant conditions in these two systems, the thesis seeks to: (i) generate evidence on microbial and chemical contamination and treatment capacities along wastewater management systems; (ii) assess prevalence and risk factors of intestinal parasitic infections in different population groups exposed to wastewater and faecal sludge; (iii) estimate the burden of gastrointestinal infections due to the exposure to wastewater; and (iv) discuss and compare risk assessment approaches and their potential for application along wastewater recovery reuse systems in selected LMICs. Research partnership: This PhD thesis is embedded in the “Resource Recovery and Reuse” (RRR) project, funded by the Swiss Agency for Development and Cooperation (SDC). Our main partner in this collaborating endeavour is WHO, while other international partners include the International Water Management Institute, the International Centre for Water Management Services, and the Department of Water and Sanitation in Developing Countries, Swiss Federal Institute of Aquatic Science and Technology. In Uganda, we closely work with the Makerere School of Public Health, the Vector Control Division of the Ministry of Health and the National Water and Sewerage Corporation. In Hanoi, our main partner is the Center for Public Health and Ecosystem Research at Hanoi School of Public…