Distribution pattern of pesticide residues in cocoa beans across the cocoa growing regions of Ghana

摘要

Pesticides have been used on cocoa for more than 50 years in Ghana. Notable among these pesticides were the organochlorines lindane, DDT and aldrin. However, after the banned of the organochlorine pesticides came other pesticide groups like the organophosphorous, carbamates and synthetic pyrethroids in cocoa production in Ghana. With cocoa being a major cash crop in Ghana, the purpose of this study was to investigate the distribution pattern of pesticide residues in cocoa beans produced in Ghana in order to advise producers and buyers of the possible residual trend in cocoa production in Ghana. A total of 44 distinct samples of fermented dried cocoa beans were randomly collected from two main cocoa beans warehouses, identified from the six cocoa growing regions in Ghana. The extracting solvent was acetonitrile, followed by two solid phase extraction cartridges; C18 and Envi-carb/LC-NH2 for extract clean-up. The investigating pesticides consist of 15 organochlorines, 12 organophosphorous and 9 synthetic pyrethroids pesticides. The results showed traces of organochlorine pesticides in cocoa beans from all six cocoa growing regions of Ghana, with Ashanti region recording the highest occurring frequency of 54 percent and the Volta region with 1.5 percent frequency of occurrence as the least.