Ecotoxicity Assessment of Platinum Nanoparticles in Soils of Different Natural Zones

The use of platinum (Pt) in automobile catalysts for the neutralization of exhaust gases increases soil pollution with platinum nanoparticles (PtNPs). The aim of the study was to assess the ecotoxicity of PtNPs through changes in the biological properties of soils with contrasting genesis in the European part of Russia: sod-podzolic soils (Dystric Luvic Stagnosol), sod-podzolic-illuvial-ferruginous soils (Luvic Stagnosols Dystric (illuvial-ferruginous)), dark gray forest soils (Greyic Phaeozems Albic), podzolized chernozems (Luvic Phaeozems Albic), and typical chernozems (Voronic Chernozems Pachic). In a model experiment, we assessed the effect of PtNPs in concentrations of 0.01, 0.1, 1, and 10 mg/kg on the number of bacteria, enzyme activity and soil phytotoxicity. Soil contamination with even small doses of PtNPs (0.01 mg/kg) was revealed to cause a decrease in the biological parameters studied. . With incrementing concentration of PtNPs in soil, the downward trend in the indicators increased. Resistance to PtNPs depended on the soil type: typical chernozem proved to be the most resistant, sod-podzolic and sod-podzolic-illuvial-ferruginous soils were the least resistant. The data obtained can be used to assess the risk and develop standards for soil contamination with PtNPs.