Heavy metals in playgrounds in Lublin (E Poland): sources, pollution levels and health risk

In the paper, the pollution of playgrounds in Lublin with heavy metals was assessed. Since playgrounds are a place of activity of children—the most vulnerable group of city residents, identifying the degree of pollution and the related health hazards is particularly important. 50 playgrounds were investigated, and samples were collected from three types of places: soil in the playgrounds, soil beneath the swings and soil in the sandpits (a total of 91 samples); heavy metal levels were determined in the < 0.05-mm fraction. The mean heavy metal levels were Cd—4.7 mg kg(−1), Cr—192.4 mg kg(−1), Cu—16.3 mg kg(−1), Hg—0.027 mg kg(−1), Ni—12.7 mg kg(−1), Pb—41 mg kg(−1), and Zn—79.8 mg kg(−1), and they were in the following order when normalised to the geochemical background: Cd > Cr > Zn > Pb > Hg > Ni > Cu. The highest mean levels occurred in the case of soil collected from beneath the swings (Cd, Cr, Ni and Zn) or soil in the playgrounds (Cu, Hg and Pb). Geochemical indices such as I(geo) and EF indicate the lack of pollution or low level of pollution with Cu, Cr, Ni, Zn and Pb. Moderate or considerable pollution with Cd and, sporadically, with Hg occurred in some playgrounds. A significant ecological risk was found for all samples due to the presence of Cd and, for about 20% of the samples, the concentration of Hg. In all the cases analysed, the values of health hazard indices (HI, CR) for children are very low and well below the hazard threshold for each element.