Original Articles
S. O. Oladeji and M. D. Saeed
Abstract
The concentration of cadmium was determined in wastewater, soil and vegetable (carrot, lettuce, onion, spinach, cabbage, tomato and okro) samples collected on seasonal basis from January, 2013 to September 2014 along Kubanni stream channels in Zaria. The results showed cadmium levels in wastewater were in the range of 1.01 – 2.02 mg/L for the year 2013 and 0.50 – 6.50 mg/L in 2014; 1.00 – 3.50 mg/Kg for the year 2013 and 1.31 – 7.15 mg/Kg in 2014 for the soil while the vegetables had concentrations in the range of 0.20 – 6.10 mg/Kg for the year 2013 and 0.60 – 5.60 mg/Kg in 2014. Statistical analysis revealed no significant difference in cadmium levels across the locations and seasons for wastewater, soil and vegetables analyzed. Pearson correlation showed moderate (r = 0.488) relationship between cadmium levels in wastewater for the year 2013 and 2014, negligible (r = 0.002) relationship for soils between these two years while low (r = 0.395) relationship was obtained for vegetables cultivated in 2013 and that of 2014 respectively. Cadmium concentrations obtained in this study was higher than Maximum Contaminant Levels set by Standard Organizations such as W.H.O. and F.A.O.