Determination of the content of Zn, Cu, Pb and Cd in the river Shkumbin (Pena) with potentiometric analysis stripping

Environmental pollution occupies an important place of surface water pollution. The use of contaminated water directly affects human health and causes long-term consequences. The most common pollutant in rivers are heavy metals such as Zn, Cu, Pb, and Cd. They contribute significantly to the pollution of the aquatic environment as they are not biodegradable and some of them have cumulative toxic properties. Heavy metals can cause many disorders and threaten human health because accumulate in certain organs. The purpose of this research was to determine the content of Zn, Cu, Pb and Cd in the river Shkumbini, Republic of Macedonia. Water samples were taken at four sampling stations (SH1, SH2, SH3, and SH4) for the period January to December 2002. Heavy metals are determined by potentiometric stripping analysis, while some results are compared with atomic absorption spectrometry. The research found that in one year, the river has been more restrained Zn, and Cu, Pb, and Cd were not detected. The annual content average with the standard deviation of Zn was 0.0227 ± 0.0157 mg/L with range 0.0060 - 0.0748 mg/L. The average with standard deviation values of the concentration of Zn in the winter, spring, summer and autumn were, 0.0252 ± 0.0099 mg/L, 0.0294 ± 0.0271 mg/L, 0.0172 ± 0.0058 mg/L and 0.0192 ± 0.0088 mg/L, respectively. The most contaminated sampling station was SH4. From the results, we conclude that the river for this period has not been contaminated with heavy metals fall into the first category, compared with the European Regulation and the official Regulation of the Republic of Macedonia.