Background: Sub-Saharan Africa (SSA) faces a deepening wastewater management crisis, with less than 10% of generated wastewater treated before environmental discharge. Conventional treatment infrastructure is inadequate, underfunded, and energy-intensive, demanding innovative, context-adapted solutions. Nanotechnology and bioremediation have independently demonstrated high pollutant removal efficiency globally but remain poorly integrated within SSA’s water sector.
Objective: This systematic review critically evaluates the current evidence on nanotechnology-based and bioremediation-based wastewater treatment approaches, assesses their adaptability to SSA’s socioeconomic and environmental realities, and proposes a hybrid nano-bioremediation framework for the region.
Methods: A structured literature search was conducted across PubMed, Scopus, Web of Science, and Google Scholar using PRISMA guidelines. Studies published between 2020 and 2025 addressing nanotechnology, bioremediation, or integrated hybrid systems for wastewater treatment with SSA applicability were eligible for inclusion. Thirty peer-reviewed articles were synthesised narratively.
Results: Engineered nanomaterials including iron oxide nanoparticles, ZnO/TiO2 photocatalysts, carbon nanotubes, and nano-zero valent iron (nZVI) achieve >85–99% removal efficiencies for heavy metals, organic dyes, and emerging contaminants. Indigenous microbial bioremediation – utilising Bacillus spp., Pseudomonas spp., Aspergillus niger, and algal consortia – offers low-cost, scalable solutions adapted to local conditions. Hybrid nano-bioremediation systems combining green-synthesised nanoparticles with immobilised microbial biofilms outperform individual approaches, achieving near-complete pollutant removal while reducing toxicity risks.
Conclusion: Context-sensitive hybrid nano-bioremediation systems, solar-powered photocatalytic reactors, and algae-based treatment represent the most promising pathways for SSA. Realising their potential requires harmonised regulatory frameworks, regional capacity building, green synthesis innovation, and sustained investment aligned with SDG 6.
