Examination of Heavy and Toxic Metals in the Kozjak lake and Treska river with Protection Measures

Abstract

The aim of our study was to examine the situation with heavy metals in water and stream sediment of Kozjak lake and Treska river, and to recommend measures to prevent pollution. Water quality and sediment was examined of aspect of the content of six very important chemical elements known as heavy and toxic metals, including: lead (Pb), cadmium (Cd), chromium (Cr), iron (Fe), copper (Cu) and arsenic (As). Modern methods of laboratory testing of chemical elements were applied: Atomic absorption spectroscopy, atomic emission spectrometry method with double plasma (AES-ICP) method and the atomic absorption spectrometry electro thermal (ETAAS). Total of 120 samples were analyzed in water and 48 samples in stream sediments. The paper will also indicate measures to protect the Kozjak lake and Treska river from possible contamination. Especially significant role for Kozjak Lake was building the Dam for production of electricity HPP "Kozjak", which is the biggest artificial dam in the country. But despite this, the Kozjak lake already used as protection from floods Skopje, fishing, еко-lake tourism but need to think and plan about using for potable water for irrigation of crops, but also as an alternative water supply of the city of Skopje.