Nowadays, among the most discussed environmental issues belongs the release of engineered and anthropogenic nanoparticles into environment [1]. The mostly used engineered nanoparticles are carbon nanotubes, fullerenes, photocatalysts while among the mostly produced anthropogenic nanoparticles are: soot, black carbon, and vehicle exhaust emissions. It was found that nanoparticles have a toxic effect on living organisms [2], but lower interest (if any) was focused on their effect on physicochemical properties of affected environmental compartments. This work demonstrates the effect of 3 nm Pt nanoparticles (NPs) in a wide range of concetrations on properties of water in sapric histosol. Soil was spiked by nanoparticles at concentrations spanning several orders to assess the threshold concentrations for each of determined properties. It was shown that NPs influence water content in soil mainly at higher relative humidites and in case that soil contains bulk water. Next, NPs also increased stability of water molecule bridges, which is a similar effect as the reinforcement of hydrogels. The larges effect had NPs on streght of water binding (evaporation enthalpy), a decrease was observed in soils dried at all investigated relative humidites and concentations. In soil that contained also bulk water was observed a decrease in ice melting enthalpy at higher concentrations. The measurements of the same properties of pure water showed similar results. As the NPs rarely occurs in soil in a free form, molecular modeling reveled a simultanoues effect of soil structure (functional groups) and NPs on water properties, which changes with hydration and NPs size. We conclude that to the effect of NPs on water physicochemical parameters should be paid more attention as the changes of are affect at environmentally relevant concentrations of Pt NPs.