| Title |
Concentrations of Heavy Metals in the Han River and its Tributaries |
| Authors |
이동수 ; 김경태 ; 홍기훈 ; 이수형 ( D . S . Lee ; K . T . Kim ; G . H . Hong ; S . H . Lee ) |
| Abstract |
Concentrations of six environmentally important heavy metals (Cd, Cu, Fe, Mn, Pb and Zn) were determined at 14 sites in the Han River and its tributaries. Water samples were taken monthly from April to November, 1987, using a standard clean-sampling technique, acidified with 4 ㎖ of 6N HCl per liter of water, and then stored in acid-leached polyethylene bottles. In the laboratory, acid-soluble metals were determined by graphite furnace atomic absorption spectrometry after fifty-fold preconcentration by Freon-APDC extraction. All sample manupulations were carried out in a class-100 laminar-flow bench to minimize possible metal contamination. All metal concentrations increased rapidly from upstream to downstream probably due to the increased anthropogenic input: Cd, Cu, Mn and Fe increased ten-fold and Pb and Zn twenty-fold. Despite the elevated concentrations in the downstream, they are still significantly lower than those of the Korean water quality standards. It appeared that there were no measurable contaminations in the upstream above Soyang Dam, where metal levels were comparable to those of Amazon and Yantze Rivers. Metal concentrations in the Han River in this study are much lower than some of the previously reported ones and the previous high values may be attributed to some analytical artifacts including analytical errors rather than the actual reduction in concentrations due to water quality improvement. |