From global north to south: governing contaminants of emerging concern in water systems

Abstract Contaminants of emerging concern (CECs), notably per- and polyfluoroalkyl substances (PFAS), pharmaceuticals, and microplastics (MPs), are increasingly detected in water systems, posing growing risks to ecosystems, human health, and socio-economic stability. This descriptive scoping review pursues four objectives: (i) quantify CEC occurrence across the Global North and South, focusing on low- to middle-income developing countries (LMIDCs); (ii) assess policy frameworks and governance readiness; (iii) propose a feasible, phased roadmap for LMIDCs; and (iv) evaluate enabling conditions and potential impacts. Literature synthesised from 2020–2025 documents widespread contamination in drinking, surface, and wastewater, with concentrations in LMIDC hotspots 5–20 times higher than in the Global North. In South Africa’s Vaal River, PFAS exceeded 400 ng l −1 , pharmaceuticals approached 1000 ng l −1 , and MPs averaged approximately 31 particles m −3 in drinking water. Policy analysis reveals fragmented monitoring and limited treatment coverage in LMIDCs, in contrast to integrated, mixture-aware frameworks in the Global North. The proposed three-phase roadmap entails: (1) establishing CEC standards and baseline monitoring, (2) piloting targeted treatment supported by extended producer responsibility schemes, and (3) embedding adaptive, mixture-aware regulation within water safety plans. Feasibility analysis identifies enforceable standards, predictable financing, laboratory capacity, and public engagement as key success factors. Full implementation could reduce PFAS and pharmaceutical loads by 50%–80%, cut MPs by over 90%, and prevent multi-billion-dollar (USD) annual PFAS-related healthcare costs. These actions would help LMIDCs such as South Africa transition from reactive to proactive water-quality governance, and advance Sustainable Development Goals 6, 3, and 14.