COMPREHENSIVE ASSESSMENT OF HEAVY METALS CONTENT IN THE WATEROF THE VERKHNETOBOLSKY AND KARATOMARSKY RESERVOIRS IN THE NORTHERN REGIONOF THE REPUBLIC OF KAZAKHSTAN

Abstract

The article presents the results of comprehensive studies on the water quality of the Verkhnetobolsky and Karatomarsky reservoirs in Kazakhstan, focusing on heavy metals. Legal and regulatory documents on state environmental control of Kazakhstan waters were reviewed, along with normative documents and scientific recommendations on water quality and toxicology, including hygienic and MPC standards. State, interstate, and international requirements for water sampling and physico-chemical analysis were studied, including winter sampling methods under ice cover.
Concentrations of metals and heavy elements were determined, and heavy metal indicators comply with hygienic safety standards for household, drinking, and cultural and general use. According to the Unified Classification System, the water quality for manganese and cadmium places the reservoirs in the fourth quality class, suitable only for irrigation and industrial use, requiring extensive treatment for household use. The Tobol River is generally classified as polluted.
Most metals show small standard deviation and variation coefficients, indicating reservoir homogeneity. However, manganese, cadmium, zinc, copper, boron, and lead show high deviations, suggesting significant content differences due to element mobility and runoff from fields and tributaries.
The results serve as reference information and methodological recommendations for assessing heavy metals and elements in freshwater reservoirs in temperate zones.