Solid Waste Characterization and Assessment of Heavy Metal Concentration in Soils and Amaranthus Spp in some Dumpsites in Uyo Metropolis, Akwa Ibom State
1Tommy, I. E., 2Ndaeyo, N. U. & 3Etuk, I. M.
1Department of Agricultural Science, University of Uyo, Uyo, Nigeria
2Department of Crop Science, University of Uyo, Uyo, Nigeria
3Department of Forestry and Wildlife, University of Uyo Uyo, Nigeria
Email: inibehe2013@gmail.com; drnundaeyo@yahoo.com; etukidongesit01@gmail.com
ABSTRACT
The study was conducted in Uyo metropolis, the capital city of Akwa Ibom State, Nigeria. Solid waste materials were collected and sorted to examined their characterized componentat each dumpsite.The concentration of some heavy metals (Cd,Pb, Ni,Fe, Zn, Cr, Cu, Mn and Co) on soils of some refuse dumpsites in Uyo metropolis and Amaranthus spp grown within the vicinity of the dumpsites were studied. Soil (0-30cm) and Amaranthus spp were sampled within the dumpsites at 5m interval and the control samples from University of Uyo permanent site farm. Soil and plant samples were analyzed using established methods and results indicated the following mean concentrations (mg kg1) in dry season in the order: Iron (724.14)> Manganese (72.46) > Lead (35.11) > Zinc (30.76)> Cadmium (18.94)>
Copper (17.73) > Chromium (12.46) > Nickel (5.30)> Cobalt (5.03). In the wet season, it was: Iron (1260.39) > Manganese (74.37) > Lead (35.06) >Zinc (32.92) >Cadmium (20.24)> Copper (19.31) > Chromium (13.80)> Cobalt (5.43)> Nickel (4.74). Plant sample in dry season indicated the following trend: Iron (307.5)> Manganese (58.14)Zinc (32.22) > Copper (18.74)> Cadmium (1.29) > Lead (1.18) >Chromium (0.79)> Nickel (0.29) > Cobalt (0.04). In wet season, it was; Iron (325.24) > Manganese
(61.70)> Zinc (35.71)> Copper (22.03) > Lead (1.40)> Cadmium (1.18)> Chromium (0.81)> Nickel (0.35)> Cobalt (0.07). Heavy metals were higher in soil than plant samples. Values in dumpsites in both soil and plant samples were higher than the control sampled. Though there was no clear trend in heavy metal concentrations at dumpsites but the highest concentration was obtained in Eka Street. Mean seasonal concentration values varied with season and were higher in wet season than dry season. Heavy metal values from soil and plant samples were higher than the safe standard recommended by WHO/FAO except for Cobalt. This implies that it is risky to consume vegetables grown on and around dumpsites since it can accumulate toxic metals. Awareness creation among consumers and ban of cultivation at dumpsite soils to forestall wastes related illness should be encouraged. Keywords: Dumpsites, Solid Waste, Heavy Metals, Soil, Amaranthus spp
