ABSTRACT

A study was conducted to investigate some physico-chemical properties and heavy metal contents of soil samples collected around Amasiri stone quarry. Soil and cassava leaf samples were collected at different distance and axes including 5m, 60m 150m, 300m and 3500rn (control) to represent A, B, C, D and E respectively. The soil and plant samples were subjected to laboratory analyses to determine cadmium (Cd), lead (Pb), nickel (Ni), copper (Cu), iron (Fe), zinc (Zn) and chromium (Cr) using Atomic Absorption Spectrophotometer (Unicam 919 Model). The results obtained revealed that the mean values of physico-chemical properties increased as the distance from quarry site increased. On the other hand, heavy metals in soils collected from sampling positions A, B and C decreased in the order Fe>Cu>Zn>Pb>Cd>Cr>Ni except for sampling positions D and E which had irregular trend. In soils around the quarry, iron was the most abundant element with mean concentration ranging from 721.12±12.39 to 2070.47±53.47 mgkg', while nickel had the least mean value ranging from 0.72±0.01 to 4.32±0.0 1. In all, there were significant differences (p<O.05) between the concentrations of heavy metals in soil samples collected around the quarry site. In plant samples, iron also had the highest mean value ranging from 4.14±0.18 to 118.40±1.05. The concentrations of heavy metals in plant sample were relatively higher than Who standards and are not recommended for human consumption.