Heavy Metal Contaminants in Stored Cocoa Beans

Abstract

Cocoa (Theobroma cacao) is one of the leading agricultural commodity of foreign exchange earnings in Nigeria, with the country been one of the leading producers in the world. Cocoa bean is a product of many important economic and industrial values, also a raw material in many capacities. Environmental pollution from human activities which are sources of heavy metals in agricultural soils include smelting, mining, exhausts, sewage, sludge, urban effluent, agrochemical use as well as fertilizer applications. Safety of consumption of cocoa products and its use as raw materials premised the study to assay heavy metal contaminations, residues and to benchmark cocoa beans of local sources to the expected safety standard of the European markets. Cocoa producing communities in Osun State were surveyed, dry cocoa beans samples were prepared, digested and heavy metals, lead, chromium, cadmium, copper, and manganese were assayed in the beans. Cadmium was not detected in all cocoa beans samples, lead detected in staggered presence (tolerable quantities) in the cocoa beans sourced from Ekosin and Ikirun. Chromium, copper and manganese were also present in varied quantities (tolerable quantities) in the cocoa beans sourced from Ekosin and Ikirun. Chromium, copper and manganese were also present in varied quantities (tolerable) in analysed cocoa beans in selected growing communities in Osun State.