DETERMINATION OF HEAVY METALS CONTAMINATION IN HUMIC ACID EXTRACTED FROM RIVER SEDIMENTS OF VARYING DEPTH

In this work humic acids were extracted from surface, below 15 cm and 30 cm depth of Kakodonga river sediments. The acids were investigated by UV-Vis spectroscopy and the heavy metal contents are determined by atomic absorption spectroscopy (AAS).Moreover, E4/ E6 ratio is determined. Our studies reveal that E4/ E6 ratio decreases from 30cm depth soil to surface which indicates that humic acid, at surface contains more aromatic groups compared to other two samples. In addition to that we found that copper (Cu) presents in the soil of river sediment is higher than other metals which can be attributed to association of Cu in process of formation of Humic acid.