Effects of automobile battery wastes on physicochemical properties of soil in Benin City, Edo State

Abstract

Difference in soil qualities has been noticeable in many soils due to anthropogenic sources, especially of automobile battery wastes. This study examines the effects of automobile battery wastes on the physicochemical properties of the soil. Soil samples for this study were collected in triplicates from three battery chargers’ workshops: Adolor, Edaiken and Uwelu in Benin City, Edo State at 0-15cm depth, in the months of August, September and October. The soil physicochemical parameters analyzed indicate variations of values in the contaminated soil over uncontaminated soil (control). Among the parameters examined, conductivity was significantly (P<0.01) higher in the contaminated soil (59.3- 184mho/cm) than in the uncontaminated soil. Notably, a more acidic pH value of 3.7-4.5 was also recorded beyond standard limits of 6.5~8.5. Meanwhile phosphorus was relatively high (1.95-3.35) and nitrogen (0.08-0.15) was low as against the control value of 2.71 and 0.18 respectively. Heavy metals such as Lead (Pb), Zinc (Zn), Cadmium (Cd), Chromium (Cr) and Copper (Cu) were present in different concentrations in contaminated soil sample which ranges from far above acceptable standard limit between (0.288-0.875, 0.757- 1.342, 0.108-0.279, 0.718-1.062 and 0.272-0.518 mg/kg) compared to their values in the control soil sample having 0.003, 0.125, 0, 0 and 0.063 mg/kg respectively. Battery wastes were found to be significant sources of Cadmium and Chromium, as none of both was detected in the control soil sample. The daily activities of auto-mechanic battery workshops have negative impacts on soil physicochemical properties. Note, the soil in mechanic battery workshops needs urgent cleanup to minimize contamination of ecological materials and public health implication. This work will prove valuable in providing baseline information for further soil quality monitoring studies in study area

KEYWORDS: Physicochemical, Heavy metals, Battery wastes, Contaminated and uncontaminated soil.