Assessment of Pesticide Residue Levels in Some Food Crops from Markets and Farms in Uyo, Akwa Ibom State, Nigeria

Abstract

Aim: This study assessed the levels of organochlorine pesticide residues in selected food crops [fluted pumpkin, chili pepper, maize (white and yellow), and beans (white and brown)] obtained from farms and markets in Uyo, Akwa Ibom State, Nigeria to quantify pesticide residues, evaluate potential dietary exposure and health risks. Methodology: Samples were randomly collected in February, 2025 from two farms and three major markets. Pesticide extraction and cleanup were performed using the Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) method, while quantification was carried out with Gas Chromatography–Mass Spectrometry (GC–MS). Dietary exposure, hazard quotient (HQ), and hazard index (HI) were calculated to estimate potential health risks. Data were statistically analysed using ANOVA at a 0.05 significance level. Results: Results revealed the presence of multiple organochlorine pesticide residues in all samples. Most detected residues, including α-BHC, β-BHC, heptachlor, aldrin, and endosulfan, exceeded WHO/FAO permissible limits. The HQ values ranged between 2.26E-05 and 4.54E-1. The highest HQ values were 2.11E-1 for Delta-BHC in white maize (WM), followed by 2.11E-1 for Aldrin in yellow maize (YM). The HI values ranged between 0.01581(PV)to 2.074778(FR). The HI values observed for all the pesticide residues were found < 1 except in FR(2.0748). Therefore, FR was considered a risk to the consumers. ANOVA shows a P-value of 0.015, reflecting statistically significant difference in Pesticide residues levels in the different food crops analysed. The F- value (2.20) was greater than the F-critical (1.83); therefore there is a statistically significant difference in pesticide residue levels between the different farms and markets samples. Conclusion: These findings raise significant health concerns as prolonged exposure to high levels of organochlorine pesticides is known to pose serious risks to consumers. While the HQ and HI suggest that immediate risks might be low, the long-term presence of these banned substances underscores the need for urgent regulatory action.