Assessment of heavy metal residues in hides of goats singed with tyres, and the effect of boiling on the heavy metal concentrations in the hides

Abstract

Tyres are reported to contain toxic materials which could pose health threats to humans. However, some butchers in Ghana singe carcasses of small ruminants with scrap car tyres. This study was therefore conducted to determine the heavy metal concentrations of carcasses singed with scrap tyres, and the effect of boiling on the heavy metal concentrations in the hides. Samples of singed goat carcasses were taken from the Cape Coast slaughter house and analyzed for the concentrations of Cu, Pb, Fe, Zn, Ni and Cd. In addition, the scraped soot from the singed carcasses was collected to determine the levels of heavy metals in it. The Cu, Zn and Pb concentrations in the tyre-singed carcasses far exceeded the Maximum Permissible Levels (MPL), rendering them unwholesome for consumption. Boiling of the carcasses marginally reduced the heavy metal concentrations, but the heavy metal residues after boiling were still higher than the MPL, indicating that boiling cannot render tyre-singed carcasses wholesome for consumption. The scraped soot from the singed animals had very high levels of heavy metal residues and therefore poses threats to soil and water bodies. Laws should be enforced in Ghana to stop local butchers from using tyres as singeing materials. Scraped soot should also be disposed appropriately in order to reduce the risk of polluting soils and water bodies