ASSESSMENT OF PESTICIDE RESIDUE IN COCOA BEANS FROM SELECTED AREAS IN ONDO STATE, NIGERIA.

Abstract

Consumers of cocoa and cocoa products all over the world are becoming increasingly aware of food safety concerns as related to its quality and pesticide use. With the new European Union (EU) Legislation on Maximum Residue Levels (MRLs) allowed on cocoa beans and its products, this study assessed pesticide residue in cocoa beans from selected towns in Ondo State, Nigeria. Dry cocoa bean samples were collected from four (4) different towns in Ondo State (Akure, Idanre, Ondo and Ore) and were evaluated for pesticide residue and bean quality. Within each selected town, four (4) cocoa stores were visited for study. Cocoa bags from the stores were randomly sampled and transported to the laboratory. Physical quality assessment, moisture content and phytochemical analysis were done. Structured questionnaires were administered to farmers in the selected towns in order to gather information on pesticide usage. Pesticide Residues analysis was carried out using Gas Chromatograph Mass Spectrophotometer (GC-MS). All the samples met the required standard for physico-chemical parameters except Akure samples which had its percentage slaty as 8% which is above the standard requirement of 5%. Generally, the pH of the cocoa beans from the four locations was less acidic, ranging from 5.60 to 5.90. Majority (78.3%) of the cocoa farmers in the studied areas were educated and 94.2% of the farmers identified that their farms were affected by pests. Also, 71.6% of the farmers resolved in using pesticides in solving this challenge but none of these farmers (0.0%) applied chemical pesticide directly on their cocoa beans. More than half of the farmers (85.8%) had undergone training on pest control and 96.7% of the cocoa farmers were fully aware of banned pesticides in Nigeria. Some of synthetic pesticides (insecticides and fungicides) used by the cocoa farmer in the studied area in Ondo State were synthetic pyrethroids and organochlorine. The active ingredient in the insecticide were majorly cypermethrin but some also have profenofos, tetramethrin, lambda-cyhalothrin and dimethoate. While the active ingredients in the fungicides were Metalaxyland Copper (1) oxide. There were no active ingredients of pesticide residue detected from these samples across the locations except the inert compounds which include Di (2-ethylhexyl) phthalate (DEHP), Methyl stearate, Hexadecanoic acid and methyl ester.Although some of these inert compounds do not have maximum residue limits, studies have shown that their accumulation overtime was found to be carcinogenic. Absence of active ingredients of pesticides in the sampled cocoa beans implies that pesticide residue is phasing out gradually in cocoa industry in Ondo State