APPLICATION OF STATISTICAL METHODS TO THE STUDY OF VARIATIONS IN HEAVY METAL CONCENTRATIONS IN THE SURFACE WATER

Abstract

Pollution of aquatic ecosystems with heavy metals is one of the key environmental problems, as these elements have a toxic effect on aquatic organisms and can accumulate in food chains, negatively affecting human health. The purpose of the presented research was to analyse the content of heavy metals (Mn, Cr, Cu, Cd, Pb and Zn) in the water of the Styr River using multivariate statistical methods to identify possible sources of pollution and dеtermine the variability of their concentrations. The Styr River is subject to anthropogenic load, including the river section in the area of influence of the Rivne Nuclear Power Plant. The study was carried out on the content of heavy metals in the water of the Styr River during 2023. Data on the  concentration of heavy metals were obtained on the basis of an analytical standardised method of optical emission  spectroscopy with inductively coupled plasma. Statistical analysis of variations in the content of heavy metals in the water of the Styr River revealed fluctuations in the concentrations of elements, in particular Mn, Zn and Cu, indicating the influence of external factors and changes in pollution sources during the year. Cd concentrations were the most stable, indicating a constant source of pollution. The correlation analysis showed an average positive correlation between Mn, Pb and Zn, as well as between Cu, Cd and Cr, indicating common sources of pollution. The principal component analysis confirmed these findings by identifying two groups of metals with similar characteristics. Seasonal fluctuations in concentrations showed that Mn and Zn were higher in winter, and Cu in spring and summer.This study is important for understanding the sources of heavy metals and their behaviour in aquatic ecosystems, which is an urgent problem for environmental protection and public health.