HEAVY METALS IN SEDIMENTS OF KOSI RIVER OF UTTRAKHAND ,INDIA
Abstract- Water, sediments and fishes are interlinked with each other in aquatic ecosystem. Heavy metals have been considered as one of the most disastrous pollutants in the river waters because of their persistence nature and magnification capacity, they can cause serious health hazard to humans through food chain. Keeping this in mind, the research work was planned to determine the level of selected heavy metals (Cd, Cu, Pb and Fe) in Kosi Rivers of Uttarakhand from December 2015 to April 2016.
Introduction- Sediments are known as major repository of heavy metals in aquatic systems. Sediments play an important role as key catalysts of environmental food cycles and the dynamics of water quality. It is known to capture hydrophobic chemical pollutants entering to water bodies and slowly releasing the contaminant back into the water column (Chapman and Chapman, 1996). According to Vermeulen and Wepener (1999), aquatic sediments absorb continuous toxic chemicals to levels many times higher than the concentration present in the water column. The functioning of an aquatic ecosystem, directly or indirectly depends on the sediment quality. The heavy metals are harmful for animals and human life depending on the concentration of intake. Some heavy metals are toxic even at low concentration, whereas some are essential for humans and if consumed in relatively high concentration they may be lethal (Forstner et al., 1981).
Material and methods
Study Area
Heavy metals were estimated in the sediments of two rivers of Uttarakhand. Kosi River at Kashipur (Distt. U.S. Nagar) and Sharda River near Banbasa (Distt. Champawat).
Heavy metals examined under study
Four heavy metals, Lead (Pb), cadmium (Cd), copper (Cu), and Iron (Fe) were determined in the water, sediments and fish tissue using Atomic Absorbance Spectrophotometer (Thermo Scientific iCE 3000 Series).
Result and discussion
The present work has been done considering the constant spreading pollution of heavy metals in water bodies. Pollution among water bodies is a major global problem. Pollution contaminates not only the water but also the sediment. The heavy metal analysis of river sediment is a useful method of studying environmental pollution due to sewage and industries. The concentration of heavy metal observed in the sediments during the study period is shown in Table:
The concentration of cadmium in sediment samples was recorded to be a mean value of 0.584±0.313 mg/kg having range between 0.26 to 1.00 mg/kg in Kosi River sediments. The average concentration of copper found was 3.808±1.166 mg/kg. The concentration observed maximum during the month of January and minimum in the month of April. The WHO guideline for maximum permissible limit of copper in sediment is 31.6 mg/kg. The mean concentration of lead was 4.130±1.737 mg/kg. Maximum permissible limit of lead in sediment is 35.8 mg/kg (W.H.O.). The concentration of lead was found within the permissible limits set by W.H.O. The concentration of iron ranged between 230.5 to 285.2 mg/kg. The average concentration was recorded 261.2±20.427 mg/kg. Sediment acts as sink for the chemical pollutants released back into the water column after adsorbing them and become source of pollution. Sediments are known to collect high concentration of heavy metals with time that might be remobilized back to the water column and to the food chain (Kar et al., 2008). Among the four metals investigated during study period, the average concentration of heavy metals was found in order of Fe > Pb > Cu > Cd. The similar trends of heavy metals were recorded in the order of Fe > Pb > Cu in both seasons from estuary and coastal area Venkatramanan (2012). In general, metal concentration was maximum in month of January and minimum in month of April except iron. The concentration of iron was maximum in month of April and minimum in month of January. The mean concentration of Cd, Cu, Pb, and Fe were observed below the limits recommended by WHO (2003) for sediments.
Conclusion:
The concentration of heavy metals in sediments was below as per the standards sets by W.H.O in the Kosi Rivers. Among the heavy metal investigated the concentration of Fe was highest followed by Pb, Cu and Cd in both the rivers. It can be concluded that heavy metal contamination was higher in Kosi River due to higher industrial waste disposal, anthropogenic activities and agricultural run-off from the catchment area.
Acknowledgement: Authors are thankful to Director of research GBPUAT, Dean C.F.Sc, Hod FRM, Hod AEM for providing the necessary facilities.
References
Chapman, D. and Chapman, E. Ed. 1996. Water quality assessments, A Guide to the Use of Biota, Sediments and Water in Environmental Monitoring, 2nd Edition, Chapman and Hall, London.
Vermeulen L. A. and Wepener V. 1999. Coastal Research Unit of Zululand, University of Zululand, Private Bag X1001, KwaDlangezwa 3886, South Africa.
Forstner, U. and Wittman, W. 1981. Metal pollution in the aquatic environment, Berlin, Heidelberg, Germany: Springer-Verlag, Vol. 272, pp. 486.
W.H.O., 1984. List of maximum levels recommended for contaminants by the Joint FAO/WHO. Codex Alimentarius Commission, Vol. 3, pp. 1-8.
Kara, Y.; Kara, I. and Basaran, D. 2004. Investigation of some physical and chemical parameters of water in the Lake Isykli in Denizli, Turkey. International Journal of Agriculture and Biology, Vol. 6, pp. 275-277.
Venkatramanan, S. and Ramkumar, T. and Vasudevan, S. 2012. Heavy metal distribution in surface sedimentsof the Tirumalairajan river estuary and the surrounding coastal area, east coast of India Arab J Geosci. Vol.7, pp. 123-130.