Pesticide Residue in Leafy Vegetables and Hygienic Practices of Handlers in a Major Market in Ibadan, Nigeria

Introduction: Leafy vegetables are a vital part of a balanced diet due to their high nutritional content, including fibre, vitamins, and minerals. However, there are concerns about the safety of the vegetables due to contamination from poor hygienic handling and pesticide residues. Major health problems associated with vegetables that contains pesticides residues are immunological suppression, hormonal changes and occurrence of different cancers. There are limited studies on the safety practices of vegetable handlers and isolated pesticides of raw and cooked vegetables. Hence, this study investigates the hygienic practices among vegetable handlers and levels of pesticide residues in a commonly consumed leafy vegetable. Methods: A descriptive cross-sectional study design and laboratory analysis was used. Through random sampling, 80 vegetable handlers in Bodija market were selected. Data on hygiene knowledge, attitudes and practices were obtained using structured questionnaires. Pesticide residues in Corchorus olitorius vegetable was analyzed using QuEChErs and Gas chromatography-Mass Spectrometry (GC-MS). The data was presented in mean, standard deviation, simple percentage and charts. The result was compared to the Maximum Residue Limits (MRLs) set by Codex Alimentarius Commission. Results: The study shows that 86.3% of respondents were female, and 13.8% were male. Majority of the respondents (82.5%) recognized dirty water used for washing the vegetables as a major source of contamination while 45.0% acknowledged handling with unclean hands as a risk factor, and 30.0% identified pesticides as potential contaminants. Only 65.0% noted poor hygiene could affects quality of vegetable. However, 50.0% practiced hand washing, and 83.8% saw no need to cover their vegetables. The laboratory analysis revealed that raw leafy vegetables contained 37 pesticide residues and metabolites with cyhalothrins (1.592, 2.930, and 4.069) mg/kg exceeding the MRLs of 0.7mg/kg. Whereas cooked samples contained only 19 pesticide residues and metabolites with chlorfenapyr (16.373, 4.566, 19.511, 2.228, 2.525, 2.596, 2.287, and 17.471) mg/kg exceeding the MRLs of 0.05 mg/kg. Fosetyl aluminum was within (MRLs) set by regulatory bodies in both cooked (0.043) mg/kg and raw samples (0.2, 0.1) mg/kg. Conclusion: The use of protective gear and proper vegetable covering are not consistently applied. Storage and handling conditions were suboptimal which may increasing the risk of microbial contamination. Also, pesticide residue was present in high concentration in the selected vegetable, which can cause health problems over time. This study highlights the urgent need for awareness of hygiene importance among vegetable handlers and stricter pesticide regulations in local markets.