AGRICULTURAL PESTICIDES AND CONGENITAL HEART DISEASE IN AFRICA: A ONE HEALTH REVIEW OF EVIDENCE AND IMPLICATIONS

Abstract

Congenital heart disease (CHD) is the most common congenital malformation and a leading cause of infant mortality worldwide, with the burden disproportionately concentrated in low- and middle-income countries. While genetic factors explain only 20–30% of cases, environmental exposures e.g agricultural pesticides, represent potentially modifiable risk factors. This narrative review examines the role of agricultural pesticide exposure in CHD aetiology through a One Health lens, with particular attention to implications for African agricultural communities where pesticide use is increasing rapidly and regulatory protections are often limited. Recent meta-analyses demonstrate positive associations between maternal pesticide exposure and CHD in offspring (pooled odds ratio 1.32, 95% CI 1.20–1.46). Specific pesticide classes such as organophosphates, pyrethroids, neonicotinoids, and herbicides such as glyphosate and 2,4-D, have been associated with increased risks of septal defects, conotruncal anomalies, and outflow tract malformations. Experimental studies using animal models and human stem cell-derived cardiomyocytes provide mechanistic insights, demonstrating that pesticides can disrupt cardiac transcription factors, induce oxidative stress, impair cell proliferation, and cause epigenetic modifications. The One Health framework reveals transmission pathways through which pesticides move from agricultural applications into soil, water, and food systems, ultimately reaching pregnant women. Animal sentinel species may provide early warning signals of developmental cardiotoxicity. Transgenerational epigenetic inheritance represents an emerging area requiring further investigation. Challenges in establishing causality include difficulties in accurate exposure assessment, the complexity of pesticide mixtures, and potential confounding. A comprehensive framework for action encompasses improved exposure assessment, strengthened regulatory reform, exposure reduction interventions, and targeted research priorities prioritising African contexts. Protecting the cardiovascular health of future generations requires coordinated One Health collaboration across disciplines and sectors, with particular urgency in Africa's rapidly intensifying agricultural landscapes.