MULTIELEMENT DETERMINATION OF HEAVY-METALS IN THE HAN RIVER OF KOREA USING LIQUID-LIQUID-EXTRACTION FLAME ATOMIC-ABSORPTION SPECTROMETRY

A method of multi-element determination of hazardous heavy metals such as Cd, Cu and Pb in the water of the Han River is described in this p aper. The liquid-liquid extraction (LLE) methods using N,N'-diethyldit hiocarbamate-methylisobutylketone (DDTC-MIBK) and ammonium pyrrolidine dithiocarbamate-methylisobutylketone (APDC-MIBK) were compared by fla me atomic absorption spectrometry (FAAS). For quantitative analysis, D DTC-MIBK extraction was adopted due to its good recoveries (average 93 .0% for 3 elements), detection limits (3.4-18.6 ng/l), repeatability ( C.V. 1.13-4.57%) and accuracy (average 97.5%). The multi-element deter mination was available because no interference effect was observed on 3 kinds of metal coexisting in an aqueous matrix. The heavy metal conc entrations in the aqueous samples collected from 12 separate points of the Han River averaged 4.204 ppb for Cd, 8.563 ppb for Cu and 2.462 p pb for Pb, respectively. Cd existed almost in suspended particles in w ater, Cu existed half in suspended particles and half in dissolved for m and Pb was almost completely found in particles and only 7% in disso lved form.