Relevance of Soil Heavy Metal XRF Screening for Quality and Landscaping of Public Playgrounds

Heavy metals have become widespread urban pollutants, exposing vulnerable age groups such as children to potential risk. Specialists need feasible approaches that can routinely assist them in customizing options for sustainable and safer urban playgrounds. The aim of this research was to explore the practical relevance of the X-ray Fluorescence (XRF) method from the perspective of landscaping specialists, and the practical significance of screening for those heavy metals that currently present elevated levels across urban environments Europe-wide. Soil samples from six public children's playgrounds of different typologies from Cluj-Napoca, Romania, were analyzed. The results indicated that this method was sensitive to identifying thresholds stipulated in legislation for the screened elements (V, Cr, Mn, Ni, Cu, Zn, As, and Pb). Coupled with the calculation of pollution indexes, this method can serve as a quick orientation in landscaping options for urban playgrounds. The pollution load index (PLI) for the screened metals showed that three sites displayed baseline pollution with incipient deterioration in soil quality (PLI = 1.01-1.51). The highest contribution to the PLI among the screened elements, depending on the site, was due to Zn, Pb, As, and Mn. The average levels of the detected heavy metals were within admissible limits according to national legislation. Implementable protocols addressed to different categories of specialists could help to transition towards safer playgrounds and more research on accurate cost-effective procedures to overcome the limitations of existing approaches is currently needed.