Environmental Health Burden of E-Waste Exposure in Informal Recycling Ecosystems: A Comparative Multi-City Study Across Nigeria

Nigeria is among Africa's largest recipients of imported end-of-life electronic equipment, and informal e-waste recycling ecosystems have emerged in multiple Nigerian cities, generating a poorly characterized but likely substantial environmental health burden for workers, surrounding communities, and the broader urban environment. This dissertation provides the first comparative multi-city study of the environmental health burden of e-waste exposure across the informal recycling ecosystems of Lagos, Kano, Onitsha, and Port Harcourt, Nigeria. A comparative sequential explanatory design combined cross-sectional environmental exposure assessments, biomonitoring studies, health outcome assessments, and qualitative investigation of ecosystem governance and worker experience. Environmental sampling at dismantling, sorting, and burning sites measured concentrations of lead, cadmium, mercury, polybrominated diphenyl ethers, and polychlorinated biphenyls in air, soil, and dust. Biomonitoring was conducted in 480 workers and 240 community residents per city, measuring blood lead, urinary cadmium, and serum polybrominated diphenyl ether levels. Neurocognitive testing, spirometry, and clinical examination data constituted health outcome measures. Disability-adjusted life years attributable to e-waste exposure were estimated per city and aggregated. Results demonstrated significantly elevated biomarker levels in all worker groups compared to control populations. Blood lead levels in children of informal recyclers were above the CDC reference value in seventy-nine percent of cases. DALYs attributable to e-waste-related lead exposure in the four cities combined were estimated at 12,400 per year. The dissertation makes an original multi-city comparative contribution and provides the first national e-waste health burden estimate. Keywords: e-waste, informal recycling, health burden, multi-city, biomonitoring.