Assessment of Agricultural Practices and Pesticide Residue Levels in Tomatoes and Garden Eggs Sold in Southeastern Nigeria

Background: Pesticide use in vegetable cultivation improves agricultural productivity but may result in harmful residue accumulation in food crops. Tomatoes (Solanum lycopersicum) and garden eggs (Solanum aethiopicum) are widely consumed in Nigeria and are frequently exposed to pesticides during cultivation and storage.
Objective: This study assessed pesticide usage practices and pesticide residue levels in tomatoes and garden eggs sold in Eke-Amobi Market, Nnewi, Anambra State, Nigeria.
Methods: A descriptive cross-sectional analytical study design was adopted. Structured questionnaires were administered to 181 farmers, distributors, and retailers involved in vegetable production and supply. Twenty vegetable samples (10 tomatoes and 10 garden eggs) were randomly collected for laboratory analysis. Pesticide residues were extracted using the QuEChERS method and analyzed using Gas Chromatography–Mass Spectrometry (GC–MS). Results were compared with FAO/WHO Maximum Residue Limits (MRLs).
Results: All respondents (100%) reported pesticide use. Common pesticides identified included cypermethrin, carbaryl, chlorothalonil, malathion, metalaxyl, deconil, and cymoxanil. Although 97.8% were aware of pesticide-related health risks, only 15.3% had received formal training on safe pesticide use, while 91.7% did not read pesticide labels and 66.3% did not use protective equipment. Laboratory analysis detected pesticide residues in 100% of samples. All tomato residues were below recommended MRLs. In garden eggs, carbaryl, deconil, and cymoxanil were within permissible limits, whereas 50% of samples exceeded the MRL for metalaxyl.
Conclusion: Tomatoes sold in Eke-Amobi Market were generally safe based on residue standards, while elevated metalaxyl residues in garden eggs may pose long-term public health concerns. Improved farmer education, pesticide regulation, and routine residue monitoring are recommended.

Pesticide residues; Tomatoes; Garden eggs; Food safety; Nigeria

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