Pesticides are a numerous and diverse group of chemical compounds which are used to eliminate pests in crop yields and households. But owing to this and other injudicious practice related to pesticide usage, pesticides become the inner part of vegetables in the shape of residues, which could be consumed by consumers thus creating health hazards. Hence, we investigated the presence of selected pesticide residues in leafy vegetable (Amaranthus spinosus) samples consumed in Donga, Taraba state, Nigeria. Five samples of leafy vegetable 50g each (AmaranthusSpinosus) which is an extensively grown vegetable in Donga local government area were collected from a vegetable farm situated about Ten meters away from Donga River. Information on the types of pesticides used on the collected samples was obtained from the farmer via oral interview. After the samples were collected, dusts on the samples were removed by washing with distilled water prior to placing them into polythene nylons. The samples were double packed in order to prevent any other contamination from coming in contact with them. The packaged samples were then labeled properly. The samples were transported to the laboratory using a cold box for analysis. The Acetate-buffered QuEChERS sample preparation method for pesticides (AOAC official method 2007.01) was used for preparing the samples, while for liquid chromatography analysis; an Agilent 1100 HPLC system was used. Nineteen pesticide residues were found present in the leafy vegetable samples analyzed. The descending order of their concentrations in the analyzed samples read; Gamma-HCH ˃ alpha-HCH ˃ methoxychlor ˃ beta-HCH ˃ DDT ˃ DDD ˃ perthane ˃ cyclohexane ˃ toxaphene ˃ mirex ˃ cyclodienes ˃ chlordane ˃ aldrin ˃ heptachlor ˃ dieldrin ˃ endosulfan ˃ dicofol > hexachlorobenzene > pentachlorobenzene, with Pentachlorobenzene having the lowest mean concentration (0.360 ± 0.063μg/kg) and gamma- HCH having the highest mean concentration (1.866 ± 0.483μg/kg). The concentrations of all these pesticide residues detected in the analyzed samples were found to be above the maximum residue limits set by FAO and WHO. This study revealed the presence of various pesticide residues in the analyzed samples of Amaranthus spinosus with organochlorines being the most present. This confirms the wide use of organochlorine pesticides in the study area. It was also observed that all the pesticide residues found present in the analyzed samples exceeded the Maximum Residue Limits (MRLs) and Acceptable Dietary Intake (ADI) which connotes the extensive use and prevalence of pesticides in the study area.
Citation: Moses A. Abah1, Otitoju Olawale, Emmanuel C. Okoli, Ozioma P. Emmanuel1, David C. Bando, Zephaniah H. Shenia (2021) Determination of Selected Pesticide Residues in Leafy Vegetables (Amaranthus Spinosus) Consumed In Donga, Taraba State, International Journal of Biochemistry, Bioinformatics and Biotechnology Studies, Vol.6, No.2, pp.9-16
Keywords: leafy vegetable, maximum residue limits, pesticide residues, pesticides, residue concentration
