Abstract
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 paper. The liquid-liquid extraction (LLE) methods using N, N'-diethyldithiocarbamate-methylisobutylketone (DDTC-MIBK) and ammonium pyrrolidine dithiocarbamate-methylisobutylketone (APDC-MIBK) were compared by flame atomic absorption spectrometry (FAAS). For quantitative analysis, DDTC-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 determination was available because no interference effect was observed on 3 kinds of metal coexisting in an aqueous matrix. The heavy metal concentrations 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 ppb for Pb, respectively. Cd existed almost in suspended particles in water, Cu existed half in suspended particles and half in dissolved form and Pb was almost completely found in particles and only 7% in dissolved form.
