Antibiotic waste as an emerging environmental contaminant: Indirect pathways linking antibiotic pollution to childhood stunting in low- and middle-income countries

Abstract

Childhood stunting persists in low- and middle income countries (LMICs), indicating the potential contribution of additional, insufficiently addressed determinants beyond nutrition and infection. This review proposes that antibiotic waste, residues and antimicrobial resistance (AMR) determinants from medical, agricultural, and domestic sources, may represent a neglected environmental risk rather than a confirmed primary cause. The narrative review synthesizes evidence across disciplines to: (i) characterize antibiotic waste contamination, (ii) map exposure pathways, (iii) describe mechanisms along an Antibiotic Waste Microbiome Growth axis, (iv) appraise epidemiological evidence and gaps, and (v) outline policy and research priorities. Antibiotic residues pervade water, soil, and biota, with microplastics amplifying exposure. Chronic low dose exposure disrupts infant gut microbiota, reduces short chain fatty acids (SCFAs), impairs gut barrier integrity, and promotes subclinical inflammation and environmental enteric dysfunction (EED), hindering growth. However, direct population-level evidence linking environmental antibiotic residues to stunting remains unavailable, underscoring that this framework is hypothesis-driven and highlighting a critical research gap. Policy priorities include effluent control, safe water access, microbiota directed foods, and integrated AMR nutrition surveillance.

Childhood stunting persists in low- and middle income countries (LMICs), indicating the potential contribution of additional, insufficiently addressed determinants beyond nutrition and infection. This review proposes that antibiotic waste, residues and antimicrobial resistance (AMR) determinants from medical, agricultural, and domestic sources, may represent a neglected environmental risk rather than a confirmed primary cause. The narrative review synthesizes evidence across disciplines to: (i) characterize antibiotic waste contamination, (ii) map exposure pathways, (iii) describe mechanisms along an Antibiotic Waste Microbiome Growth axis, (iv) appraise epidemiological evidence and gaps, and (v) outline policy and research priorities. Antibiotic residues pervade water, soil, and biota, with microplastics amplifying exposure. Chronic low dose exposure disrupts infant gut microbiota, reduces short chain fatty acids (SCFAs), impairs gut barrier integrity, and promotes subclinical inflammation and environmental enteric dysfunction (EED), hindering growth. However, direct population-level evidence linking environmental antibiotic residues to stunting remains unavailable, underscoring that this framework is hypothesis-driven and highlighting a critical research gap. Policy priorities include effluent control, safe water access, microbiota directed foods, and integrated AMR nutrition surveillance.