The Role of Maize Tassels in Amelioration of Heavy Metals from Contaminated Soils and its Effects on Vegetables.

Abstract

Vegetables depend on water as solvent for their growth and have greater potential of accumulating in their edible parts heavy metals which are dangerous to human health.  Maize tassel was applied to soil to determine its role in removal of heavy metals such as Manganese (Mn), Iron (Fe), Cadmium (Cd) and Zinc (Zn) from the contaminated soil with cabbage as the test crop. The average mean concentration of the heavy metals after twenty one and fifty one days were; Mn (0.402 mg/kg and 7.427 mg/kg), Fe (0.894 mg/kg and 4.838 mg/kg) and Zn (0.155 mg/kg and 1.073 mg/kg) respectively. The concentration of cadmium in the wastewater sample used was 0.680mg/l, and its concentrations in tap water (<0.002mg/l), in soil (<0.002mg/kg) were below the detection limit. The enrichment factor for Mn, Fe and Zn in soil treated with maize tassel (T1) are 9.73, 10.70 and 5.23 respectively, whereas treatment without (T2) are 1.05, 1.86 and 4.52 respectively. The high enrichment of T1 is attributed to the availability of the active site within the tassel absorbent.

Keywords: Heavy metals, maize tassel, contaminated soil, wastewater.