Article Title: Copper (Cu), lead (Pb) and Zinc (Zn) distribution in the Granville brook Dumpsite soil, Sierra Leone
This study investigates current levels of Cu, Pb and Zn metal pollution and factors influencing their distribution in the soil of the Granville Brook dumpsite. Soil samples were collected from four different points (A, B C and D) of the dumpsites at a depth of 15cm below the surface. Samples were separated into three size fractions using mesh sizes of 1mm (large), 600 μm (medium) and 150μm (small) followed by the determination of soil parameters (organic matter and cation exchange capacity), pH and heavy metals using standard proceedures. Pb, Zn and Cu were analysed using the Flame Atomic Absorption Spectrophotometer. Soil pH from all four locations was slightly basic 7.90 – 8.81. Results of one way ANOVA showed significant difference of the metal levels between the various locations of the dumpsite (ANOVA, p<0.05). Order of magnitude of metals within the dumpsite in all four locations can be summarised as C>B>D>A. Mean ± SD (mg/Kg) of the various metals are: For Cu: 410.42±258.48; 527.60±269.83, 677.29±354.48 for the large, medium and small sizes respectively. For Zn: 989.62±671.55; 1156.43±783.78, 1359.03±765.62 for the large, medium and small sizes respectively and for Pb: 104.31±65.78; 126.80± 65.45, 195.51±114.68 for the large, medium and small sizes respectively. General order of the magnitude of the metals is Zn>Cu>Pb. Similarly, soil organic matter and cation exchange capacity increased as the particle size decreased. The study revealed high level contamination of dumpsite soil with the three metals investigated especially for Zn with considerable variation in concentration within the site.