The levels of organochlorine (OC) pesticide residues in maize grains obtained from open markets and stores in Ile-Ife and Ondo were evaluated and compared with established safety limits. The pretreated samples were Soxhlet extracted and the extracts obtained were analysed for their OCPs content using a Gas Chromatograph coupled with an Electron Capture Detector (GC-ECD). A total of 17 OCPs and their residues were detected in most of the samples with the percentage occurrence ranging between 20 and 100%, and the levels found exceeding their Maximum Residue Limits (MRLs). The mean concentration of -HCH, Endosulfan II and Endrin aldehyde were 0.118, 0.592 and 1.039 mg kg -1 , respectively for maize samples obtained from open markets in Ile-Ife. However, maize samples from Ondo had higher levels of Heptachlor epoxide with a mean concentrations of 13.622 and 18.642 mg kg -1 for open markets and stores, respectively. Amounts of OC pesticide residues detected in the maize samples indicated that samples from stores had higher residue levels than those from open markets. The level of OC pesticides contamination of the analysed maize samples portends both short-and long-term public health concerns, calling for regular monitoring of pesticide residues in maize grains and other food items to ensure higher food quality and safety.

No abstract

PurposeThe study assessed the levels of organochlorine pesticides (OCPs) and their potential non-carcinogenic and carcinogenic health risks in four regularly consumed fruit vegetables.Design/methodology/approachThe OCPs’ residues were quantified using a gas chromatograph coupled with an electron capture detector (GC-ECD) and the dietary exposure of children, and adult consumers to the detected OCPs was evaluated using carcinogenic and systemic health risk estimations.FindingsAldrin, endrin, endrin aldehyde, a-endosulfan, β-endosulfan, endosulfan sulphate, heptachlor, heptachlor epoxide and dieldrin were detected in the four fruit vegetables. The predominant OCP residue in carrot, cucumber, tomatoes and watermelon was endosulfan sulphate with mean concentrations of 2.532 mg kg−1, 1.729 mg kg−1, 2.363 mg kg−1 and 1.154 mg kg−1, respectively. The residues levels in some of the fruit vegetables were higher than their respective maximum residue levels (MRLs) of 0.01–0.05 mg kg−1 set by the European Commission with concentrations above MRLs ranging between 25.5% and 100%. The systemic health risk estimations showed that the hazard index (HI) values for carrot (3.20), cucumber (9.25), tomatoes (50.21) and watermelon (16.76) were >1 for children consumers and the respective HI values of 2.87, 15.57 and 5.20 for adult consumers of cucumber, tomatoes and watermelon were >1 which implies potential systemic health risks. Four carcinogens (aldrin, dieldrin, heptachlor and heptachlor epoxide) had cancer risk index values greater than the acceptable risk of 1 in 1 million for both adult and children consumers.Originality/valueThe paper shows that despite the ban on the use of OCPs in Nigeria, they are still being used for agricultural production especially on some locally produced and regularly consumed fruit vegetables as reported in the present study. The non-existence of surveillance programmes on pesticide usage and the lack of proper monitoring of pesticide residues in food products including fruit and vegetables must have contributed to the levels of the detected OCP in the samples analysed. The current daily intake of OCP via contaminated vegetables may pose potential health risks to both the children and adult consumers of the fruit vegetables.