Encroachment, disposal of untreated domestic and industrial wastewater and dumping of solid wastes have degraded the overall quality of the river Turag, which is located in Dhaka—the Capital City of Bangladesh. The present study investigated the extent of pollution of sediments of this river and analyzed the regional variability for the concentrations of Cr, Pb, Zn, Cu and Cd—all of concern because of their potential toxicity, using atomic absorption spectrophotometer. As per US EPA sediment quality guideline, metal concentrations ranged between Cd: 0.00-0.80, Cr: 32.00-75.50, Cu: 46.30-60.00, Pb: 28.30-36.40, and Zn: 94.60-190.10 mg/kg in the Turag river sediments. Cr, Cu, Zn belongs to moderately to highly polluted, Pb and Cd belongs to not polluted for Turag river. The heavy metals contamination in the sediments were also evaluated by applying Index of geo-accumulation (Igeo), contamination factor (Cf), pollution load index (PLI) etc. Toxicity characteristics leaching procedure (TCLP) test (US EPA 1311)for sediment samples have been performed also for metals (Pb, Cd, Cr, Cu and Zn) to determine the readily toxicity level of heavy metals. Sieve analysis of sediment performed in this study to determine the physical characteristic of sediment samples. The metal concentrations are well below the regulated level as per US EPA. This index can be complemented with the contamination index, which allows more site-specific and accurate information on contaminant levels. If the aim of work on contamination evaluation is to assess the overall contamination of a study area, the indices are highly appropriate.
Cite this paper
Z. Banu, M. Chowdhury, M. Hossain and K. Nakagami, "Contamination and Ecological Risk Assessment of Heavy Metal in the Sediment of Turag River, Bangladesh: An Index Analysis Approach," Journal of Water Resource and Protection, Vol. 5 No. 2, 2013, pp. 239-248. doi: 10.4236/jwarp.2013.52024.
 DoE, “Water Quality Data of Rivers Buriganga, Meghna, Balu, Shitalakhya, Jamuna (1991-2000),” Department of Environment, Dhaka, 1997.
 O. Akoto, J. H. Ephraim and G. Darko, “Heavy Metal Pollution in Surface Soils in the Vicinity of Abundant Raiway Servicing Workshop in Kumasi, Ghana,” International Journal of Environmental Research, Vol. 2, No. 4, 2008, pp. 359-364.
 H. Ghrefat and N. Yusuf, “Assessing Mn, Fe, Cu, Zn and Cd Pollution in Bottom Sediments of Wadi Al-Arab Dam, Jordan,” Chemosphere, Vol. 65, No. 11, 2006, pp. 2114-2121. doi:10.1016/j.chemosphere.2006.06.043
 D. C. Thomilson, D. J. Wilson, C. R. Harris and D. W. Jeffrey, “Problem in Heavy Metals in Estuaries and the Formation of Pollution Index,” Helgol. Wiss. Meeresunlter, Vol. 33, No. 1-4, 1980, pp. 566-575.
 P. K. Saha and M. D. Hossain, “Geochemical and Ecotoxical Approach for Evaluation of Heavy Metal Pollution in the Buriganga River Sediment,” Proceedings of Bangladesh Geotechnical Conference, 2010.
 G. Muller, “Index of Geoaccumulation in Sediments of the Rhine River,” Journal of Geology, Vol. 2, No. 3, 1979, pp. 108-118.
 J. M. Martin and M. Meybeck, “Elemental Mass Balance of Materials Carried by Major World Rivers,” Marine Chemistry, Vol. 7, No. 3, 1979, pp. 173-206.
 J. Wilson, “Evaluation of Estuarine Quality Status at System Level with the Biological Quality Index and the Pollution Load Index (PLI),” Biology and Environment B, Vol. 103, 1987, pp. 47-59.
 L. Hakanson, “Ecological Risk Index for Aquatic Pollution Control, a Sedimentological Approach,” Water Research, Vol. 14, No. 8, 1980, pp. 975-1001.
 P. K. Saha and M. D. Hossain, “Assessment of Heavy Metal Contamination and Sediment Quality in the Buriganga River, Bangladesh,” 2nd International Conference on Environmental Science and Technology, IPCBEE, Singapore, 26-28 February 2011.
 G. Muller, “The Heavy Metal Pollution of the Sediments of Neckars and Its Tributary: A stocktaking,” Chem. Zeit., Vol. 105, 1981, pp. 157-164.