Children's playgrounds and urban pollution: Ecological and health risks from Cr, Ni, Pb, As, Cd, Cu, and Zn.

We are observing a growing awareness of the need to protect the environment, and initiatives that promote parks for recreation and enjoyment for both adults and children are also being encouraged. Soil pollution in "green urban oases" is increasing due to the development and construction of industrial facilities nearby, the expansion of transportation networks, and the increasing amount of various types of construction waste. In this study, the concentrations and distributions of PTEs (Cr, Ni, Pb, As, Cd, Cu, and Zn) were measured in the topsoil of 17 children's playgrounds with natural play areas in the urban region of Belgrade, Serbia. After microwave-assisted acid digestion of the soil samples, measurements were conducted using an inductively coupled plasma optical emission spectrometer (OES-ICP). The data quality was validated through recovery tests with the certified reference material NIST 2711a. Potential sources of PTEs were identified using a chemometric approach involving principal component analysis (PCA). The PCA results revealed two factors accounting for 81.47% of the total variance, highlighting the importance of specific elements (PC1: Cd, Zn, Hg, Cu, and Pb; PC2: Ni, Cr, and As). Additionally, the ecological risk linked to the analyzed PTEs was assessed using various pollution indicators: contamination factor (CF), potential ecological risk index (RI), geo-accumulation index (Igeo), and Nemerov index (I). An assessment of non-carcinogenic health risks for children resulting from exposure to PTEs was also performed. The results of this study on PTEs provide a robust framework that can be applied to other urban environments.