Pollutant levels in effluent samples from tanneries and textiles of Kano industrial areas, Nigeria

Effluent samples from tanneries and textile industries from Kano industrial area of Challawa, Bompai and Sharada industrial area were collected on quarterly basis from June to September, 2007 (Rainy season), November,2007 – February, 2008 (Harmattan season) and March – May, 2008 (Dry season) to reflect the seasonal factors. Effluents from ten industries were sampled and determined for physicochemical parameters. The physicochemical pollutants indicators determined include; Biological oxygen demand (BOD) and Chemical oxygen demand (COD) which all depend on the concentration of dissolved oxygen (DO) in effluent samples. Anions and trace elements were also determined. The above parameters were determined using standard procedures. From the results of the study, the concentrations of BOD, COD, DO, nitrate, nitrite, sulphate, phosphate, chloride and heavy metals were higher than the limits set by WHO for the discharged of tanneries and textile effluents into river. Result of analysis of variance (ANOVA) showed that variations between some industries were statistically significant (p≤0.05), but there were no marked seasonal variation in all the industries studied. Based on the high levels of the above parameters, it can be suggested that regular monitory of pollutants in the tannery and textile effluent are necessary to ensure proper discharge of these effluents into receiving river

SEASONAL VARIATION ASSESSMENT IN THE CONCENTRATIONS OF HEAVY METALS IN WATER AND SEDIMENT SAMPLES FROM KOMADUGU RIVER BASIN, YOBE STATE, NIGERIA

Water and sediment samples were collected during the rainy and dry season from Komadugu river basin, Yobe State, Nigeria for the determination of some heavy metals which include Pb, Fe, Cu, Zn, Cd, Ni, Mn, As, Cr. Digestion of water and sediment samples were carried out using standard procedures, the concentrations of heavy metals were determined using Perkin-Elmer A Analyst 300 Atomic Absorption Spectroscopy (AAS) and X-Ray Fluoresces (XRF) to provide for comparative analysis between the methods. The concentrations of all the heavy metals in the water samples during the rainy and dry season ranged from 1.10E-04 to 7.74E-01 mg/L, Fe was observed to show the highest total concentrations (1.35E+02 mg/L) during the dry season, while as shows the total lowest concentration with a value of (1.00E-03 mg/L) during rainy season. The concentrations of all the heavy metals in the sediment samples were significantly higher at sampling point S8 with a value of (2.99E+04 mg/kg) during the dry season, while the lowest value was observed at sampling point S1(4.00E-02 mg/kg). Fe was the most dominant in all the sampling points, while Pb shows the lowest concentration. The results further indicate that, the concentrations of all the heavy metals were significantly higher in the sediment samples when compared with the water samples