ABSTRACT

Introduction: Pesticide poisoning is a critical public health challenge in low-income countries, yet biomonitoring data to quantify exposure is severely scarce. Globally, pesticide poisoning affects approximately 41 million people annually with a minimum 300,000 deaths, leading to health problems as a result of the exposures. This study moves beyond self-reported practices to biochemically assess the extent of pesticide exposure among smallholder farmers in Abuja, Nigeria, and explores the concerning gap between perception and reality.
Methods: A mixed-methods approach was employed, including a cross-sectional survey (n=308), 8 focus group discussions (FGDs), and gas chromatography-mass spectrometry (GC-MS) analysis of six urinary dialkylphosphate (DAP) biomarkers in a subset of 54 farmers.
Results: Biomonitoring confirmed universal internal exposure: urinary diethylphosphate (DEP) and diethylthiophosphate (DETP) were detected in 100% of farmers, with three additional dialkylphosphate metabolites present in 85–94% of the cohort. This contamination starkly aligns with prevalent unsafe practices. While 90% prioritized pesticide effectiveness, only 47.7% could correctly define Personal Protective Equipment (PPE). Critically, 86% experienced pesticide spillage onto skin or eyes, and only 3.9% stored pesticides safely. FGDs revealed that economic constraints, learned behaviors from family, and ineffective vendor advice perpetuate this high-risk cycle.
Conclusion and Implications: The study provides objective biochemical evidence that contradicts self-reported safety perceptions. There is a dangerous dissonance between farmers’ operational priorities and their documented toxic exposure. Interventions must extend beyond basic awareness campaigns to address the systemic and socioeconomic drivers of unsafe practices. We advocate for farmer-centered training, strict enforcement of pesticide regulations, and promotion of Integrated Pest Management (IPM) to translate knowledge into measurable reductions in exposure.

KEYWORDS

Pesticides, Smallholder Farmers, Biomonitoring, Dialkylphosphates, Biomarkers

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Cite this article

Cegbeyi, E. A. M., Egenti, B. N., Jamda, A. M., Isara, A. R., & Abah, S. O. (2026). Biomonitoring of Organophosphate Pesticide Exposure among Smallholder Farmers in Nigeria: A Mixed-Methods Study of Knowledge, Practices, Gap in Perceived Safety and Internal Dose. INTERNATIONAL JOURNAL OF HEALTH & MEDICAL RESEARCH, 5(7), 588-600. https://doi.org/10.58806/ijhmr.2026.v5i7n03