Assessment Of Four Heavy Metals In Cassava Grown In Umudike:- Nnachi Chimereucheya L

ABSTRACT ix Cassava, a root tuber crop that is consumed in Nigeria and most African countries as a staple food is a major source of carbohydrate. Four cassava samples were analyzed to ascertain the levels of four heavy metal contaminants comprising lead, cadmium, arsenic and mercury which may be as a result of human activities such as fertilizer application, pesticides, compost manure and sewage disposal which are major practices in rural areas, or as a result of natural processes such as weathering ofrocks which deposit these heavy metals in the soil and is then absorbed by plants in the process ofplant growth and nutrition. In a selected rural region, four samples of cassava were collected and analyzed. Lead, cadmium, arsenic and mercury concentrations were determined using a method described by Gregg in 1989. The mean concentration levels of arsenic, cadmium, lead and mercury were 0.42 +0.00, 0.41 ±0.00, 0.52+0.00 and 0.29+0.00 respectively. The concentration of lead, cadmium, arsenic and mercury were found to be high when compared with the WHO recommended concentration levels of these metals in food which are O.lOmg/kg, O.lOmg/kg, 0.3mg/kg and O.lmg/kg respectively. This implies that lead arsenic, cadmium and mercury are present in the cassava tubers in such a level that it can become toxic to the health ofinhabitants ofthat locality when consumed.