Heavy metal concentrations in soils and accumulation in amaranthus hybridus grown near solid waste dumpsites in gombe, Nigeria

A study of the concentrations and accumulation of heavy metals (Pb, Cd, Ni, Fe and Zn) in Amaranthus hybridus (green spinach) plant around four solid waste dumpsites in Gombe metropolis, Nigeria was carried out using Atomic Absorption Spectrophotometer (A Analyst 400 Perkin Elmer USA). The result indicated the following trend in heavy metals’ concentrations in both dumpsite soil and plant samples: Fe>Zn>Pb>Ni>Cd. Roots showed highest metal concentration followed by leaves and then stems. The Accumulation Factor (AF) was calculated for assessment of the plant’s bio-accumulation potential. The Accumulation Factor (Transfer Ratio) indicated the following trend: Cd>Pb>Ni>Fe>Zn. Although the metals concentrations in Amaranthus hybridus were less than 1000mgKg-1, their average accumulation factors (AF) being greater than 1.00 for the five heavy metals studied is an indication of the plant’s potential as hyper accumulator. Thus, it may be risky to consume Amaranthus hybridus grown at close proximity to dumpsites since they can greatly accumulate much of these toxic metals.