Trace Metals in The Effluents and Water of The Bhairab River at the- Vicinity of Khulna Newsprint and Hardboard Mills Ltd. Khulna, Bangladesh

Abstract

An investigation was carried out to evaluate the status of some trace metals in surface water collected from the Bhairab River at the vicinity of Khulna Newsprint & Hardboard Mills Ltd., Khulna. The samples were analyzed seasonally from December 1998 to November 1999 by employing air acetylene flame in combination with hollow-cathode lamps as well as Atomic Absorption Spectrophotometer (Perkin Elmer Model 3110).Some physico-chemical parameters of surface water at the studied area were determined simultaneously by standard methods. The maximum and minimum concentrations of Fe, Cu, Cd, Mn, Pb, Cr, Co & Ni were noted in surface water samples as 2756 µg.L⁻¹ & 62.52 µg.L⁻¹; 66.14 µg.L⁻¹ & 2.00 µg.L⁻¹; 15.52 µg.L⁻¹ & <2.08 µg.L⁻¹; 724 µg.L⁻¹ & 7.25 µg.L⁻¹; 70.7 µg.L⁻¹ & <5.47 µg.L⁻¹; 61.3 µg.L⁻¹ & <14.7 µg.L⁻¹; 42.18 µg.L⁻¹ & <2.11 µg.L⁻¹ and 64.74 µg.L⁻¹ & <2.46 µg.L⁻¹ respectively.The maximum and minimum values of physico-chemical parameters of surface water in the studied area, i.e. Temperature, Hydrogen ion concentration, Electric conductivity, Dissolved oxygen, Bio-chemical oxygen demand, Chemical oxygen demand, Total suspended solids, Total dissolved solids, Total solids, Total alkalinity and Chloride were as 32°C & 24°C; 7.4 & 6.3; 2400 µmhos.cm⁻¹ & 1100 µmhos.cm⁻¹; 2.11 mg.L⁻¹ & 0 mg.L⁻¹; 530.4 mg.L⁻¹ & 204 mg.L⁻¹; 3829 mg.L⁻¹ & 5 mg.L⁻¹; 400 mg.L⁻¹ & 200 mg.L⁻¹; 3100 mg.L⁻¹ & 200 mg.L⁻¹; 3300 mg.L⁻¹ & 400 mg.L⁻¹; 88 mg.L⁻¹ & 32 mg.L⁻¹; 125 mg.L⁻¹ & 80 mg.L⁻¹ respectively.Trace metal concentrations in surface water were observed higher in some stations. The values of physico-chemical parameters in the Bhairab River at the vicinity of the Khulna Newsprint Mills were recorded exceeding the different certified limits with some few exceptions.