DOI: 10.5061/dryad.d2547d892
title: Average seasonal contents and standard deviations of chemical elements in drinking water samples of Almaty

description: Water is an important component of all life on Earth, and water pollution
 with heavy metals can lead to detrimental consequences for public health.
 The purpose of this study was to determine the health risks caused by
 trace elements present in the drinking water supply systems of Almaty
 City. As part of this research, the elemental composition of 78 drinking
 water samples taken in winter, summer, and autumn of 2023 in different
 areas of the city was studied.Based on the data obtained, drinking water
 contamination indices were calculated for heavy metal groups, and the
 degree of water suitability for drinking purposes was assessed for each
 sampling point.
description: Inductively coupled plasma mass spectrometry (ICP-MS) and inductively
 coupled plasma optical emission spectrometry (ICP-OES) techniques are used
 at the Institute of Nuclear Physics for analyzing the elemental
 composition of liquid samples.
description: # TRACE ELEMENT COMPOSITION OF DRINKING WATER IN ALMATY
 [https://doi.org/10.5061/dryad.d2547d892](https://doi.org/10.5061/dryad.d2547d892) ## Description of the data and file structure 1\. The heavy metal content of hazard classes 3 and 4 should not exceed the Maximum Acceptable Concentrations (MAC) for drinking water adopted in the Republic of Kazakhstan [14, 15]. 2\. The heavy metal index (HMI) was calculated for chemical elements belonging to hazard classes 1 and 2, and standardized according to the sanitary-toxicological hazard. The calculation was performed according to the formula [14]: ![](file:///C:\Users\5User\AppData\Local\Temp\msohtmlclip1\01\clip_image002.png),                                                                                                                                 (1) Where Сi – average seasonal concentration of the i-th chemical element, μg/L, MACi - maximum acceptable concentration of the i-th chemical element, μg/L, n– number of analyzed chemical elements of hazard classes 1 and 2, the average seasonal contents of which in water samples exceed the detection limit (DL) of the applied method. The HMI value should not exceed 1. The elemental composition of drinking water samples collected at 26 selected points in Almaty in winter, summer, and autumn of 2023 was studied using ICP-MS and ICP-OES techniques. Thus, the chemical element contents As, Be, Co, Cd, Cu, Li, Mo, Ni, Pb, Se, U, Hg, Al, Ba, Cr, Fe, Mn, Sr, V, Zn and K, Mg, Na, Ca were obtained. The average contents for the three data samplings and the standard deviations for each sampling point were calculated based on the data obtained. The As, Be, Cd, Se and Hg element contents do not exceed the technique detection limit, which is 0.5 µg/L for As, 0.03 µg/L for Be, 0.05 µg/L for Cd, 3 µg/L for Se and 0.1 µg/L for Hg for all measured samples. Table 1 presents the average contents (![](file:///C:\Users\5User\AppData\Local\Temp\msohtmlclip1\01\clip_image004.png)) and standard deviations (SD) for chemical elements whose contents exceeded DL. The table also shows the MAC and hazard classes for each chemical element adopted in the Republic of Kazakhstan [14, 15]. The exceptions are U, Ca, and K, for which there is no MAC (U and K) or hazard class (K and Ca) in the regulatory literature. As shown in Table 1, uranium is an important chemical element for Almaty in assessing the degree of water suitability for drinking purposes. Therefore, uranium in drinking water standards adopted in other countries has been considered. Table 2 presents the MAC values for uranium used in different countries. As can be seen from Table 2, the MACs for different countries vary greatly, ranging from 2 µg/L (Japan) to 964 µg/L (Czech Republic). We used the maximum acceptable concentration value adopted by the World Health Organization (WHO), which is 30 µg/L, to calculate the heavy metal contamination index of drinking water in the Almaty-HMI. The HMIs were calculated for each sampling point using (1). The values obtained are presented in the last column of Table 1.