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