Comparative Studies of the Biosorption of Heavy Metals (Zinc and Lead) using Tea Leaves (Cammelia Sinensis) and Tea Fibre as Adsorbents

Abstract

Heavy metals as described by Barrera et al., 2006 are elements whose density is equal to or greater than 6.0 g/cm e.g Lead (Pb), mercury (Hg), cadmium (Cd) and arsenic (As).They have for long been used by man in building materials, as medicine, as pigments or as additives for petrol (Hylander and Meili, 2003), (Järup, 2003). Researchers later proved that heavy metalsgenerally poses a great deal of problems to mankind due to its presence in the environment at concentrations above threshold(Seker et al., 2008).Anthropogenic activities such as industrial effluents, mining, smelting, manufacture of explosives, metal plating, domestic effluents, leaching and run-offs from garbage are responsible for the risen cases of these toxic elements in the environment(Trueby, 2003). and the danger associated to the presence of these heavy metals have been attributed to bioconcentration and bioaccumulation in the food web in different locations (Nussey, 1998) enhanced by their ability to be transported to a distance usually by water(Bradl, 2005). Heavy metal pollution of the environment is now one of the most serious environmental problems worldwide which calls for ways of remediation because they are acutely and exceedingly toxic, indestructible (non-biodegradable) and they bioaccumulates thereby causing different health complications e.g. lead poisoning damages the kidney, liver, brain, reproductive systems and even the nervous systems (Naiya et al., 2009). Also, excess ingestion of zinc can lead to microcytosis, impaired immune response, neutropenia and hypocupremia, (Appelo and Postma, 2007).