Environmental exposure pathways and health outcomes among residents living near an open municipal dumpsite in The Gambia

Background Open dumpsites remain the predominant waste disposal method in low- and middle-income countries; however, epidemiological evidence quantifying specific exposure-disease pathways is limited. We investigated the associations between four environmental exposure pathways and multiple health outcomes among residents living near an open municipal dumpsite in The Gambia, Africa. Methods We conducted a cross-sectional prevalence study of 380 adults residing within 100–500 m of the Bakoteh dumpsite in 2017. Self-reported exposure to smoke, dust, pests, and odor was assessed alongside multisystem health outcomes (respiratory, cardiovascular, gastrointestinal, dermatological, neurological). Adjusted prevalence ratios (aPRs) with 95% confidence intervals were estimated using Poisson regression with robust (sandwich) standard errors, controlling for age, sex, education, proximity, and duration of residence. Population attributable fractions were calculated from adjusted PRs using the Miettinen formula. Effect modification by age and sex was examined. Results Outcome prevalence was high (skin disorders 76.6%; gastrointestinal disease 81.6%; cardiovascular conditions 68.4%; headache 66.8%). All four exposures showed significant proximity gradients (all p < .01). Smoke exposure (93.7% prevalence) demonstrated the strongest associations: aPR 5.89 (95% CI 2.03–17.08) for skin disorders, 3.56 (1.78–7.14) for gastrointestinal disease, 2.25 (1.11–4.55) for headache, and 1.79 (1.01–3.17) for cardiovascular disease. Pest exposure was independently associated with gastrointestinal disease (aPR 1.83, 1.45–2.31), skin disorders (1.80, 1.41–2.29), and cardiovascular disease (1.33, 1.08–1.64). Dust exposure was associated with cardiovascular disease (aPR 1.41, 1.23–1.61). Population attributable fractions ranged up to 82% for smoke and skin disorders. Cumulative exposure showed a clear dose-response: adjusted PR per additional exposure for cardiovascular disease was 1.25 (1.15–1.36), with prevalence rising from 22.2% (zero exposures) to 86.9% (four concurrent exposures). Conclusions Proximity to open dumpsites is associated with an elevated prevalence of multisystem morbidity through multiple co-occurring exposure pathways. Smoke from open burning shows the strongest associations, while pest exposure is independently associated with gastrointestinal and dermatological morbidity, and dust with cardiovascular morbidity. The cross-sectional design precludes causal inference; longitudinal studies with objective environmental monitoring and biomarker-based outcome ascertainment are needed to establish temporality. The observed associations may help support further investigation of the potential health risks of living near open municipal dumpsites in low-resource settings.