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In recent years, silver nanoparticles (AgNPs) are increasingly used in various industries due to their antibacterial properties, which lead to an increase in pollution of the environment and soil ecosystems. However, the ecological effects of soil pollution by AgNPs were poorly studied than that with AgNPs of other metal-based NPs. The aim of this study is to assess the influence of AgNPs on the biological properties of Haplic Chernozem. Silver was introduced into the soil in the form of AgNPs with a concentration of 0.5; 1; 5; 10; 50, and 100 mg/kg in laboratory conditions. The influence of AgNPs on the biological properties of Haplic Chernozem was assessed 30 days after contamination. The degree of reduction in biological properties depends on the AgNPs concentration in the soil. This study showed that the sensitivity to contamination by AgNPs in the total number of bacteria and enzymatic activity was more than that in the abundance of bacteria of the genus Azotobacter. The integrated index of biological state (IIBS) of Haplic Chernozem was decreased by contamination with AgNPs. Silver nanoparticles in the concentration of 10 mg/kg caused a decrease in the indicator by 13% relative to the control. It also decreased IIBS by doses of 50 and 100 mg/kg by 22 and 27% relative to the control. All used biological indicators could be used for biomonitoring, biodiagnosis, bioindication, and regulation of ecological condition of soil contamination by AgNPs.

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The environmental behavior of antibiotics is not well known and the precise environmental risk assessment is not practical. We studied the impact antibiotics (benzylpenicillin, pharmasin and nystatin) at different concentrations (100 and 600 mg kg −1 ) on population densities of microorganisms and enzymatic activity of ordinary chernozems in model experiments. The applied doses of antibiotics had definite suppressing effects on population densities of microorganisms (up to 30-70% of the control) and on the soil enzymatic activity (20-70% of the control). The correlation analysis of the obtained data revealed positive correlation of enzymes of two studied classes (dehydrogenase, invertase) with a number of micromycetes (r = 0.63, r = 0.65, respectively), catalases with ammonifying bacteria (r = 0.73) and the return correlation of phosphatase with amylolytic bacteria (r = -0.80). The effect of antibiotics on the biological properties of the chernozem lasted for a long time. The studied parameters were not completely recovered in 120 days.

The use of silver in various spheres of life and production leads to an increase in environmental pollution, including soil. At the same time, the environmental consequences of silver pollution of soils have been studied to a much lesser extent than those of other heavy metals. The aim of this study is to estimate silver ecotoxicity using the soil state biological indicators. We studied soils that are significantly different in resistance to heavy metal pollution: ordinary chernozem (Haplic Chernozems, Loamic), sierosands (Haplic Arenosols, Eutric), and brown forest acidic soil (Haplic Cambisols, Eutric). Contamination was simulated in the laboratory. Silver was introduced into the soil in the form of nitrate in doses of 1, 10, and 100 mg/kg. Changes in biological parameters were assessed 10, 30, and 90 days after contamination. Silver pollution of soils in most cases leads to deterioration of their biological properties: the total number of bacteria, the abundance of bacteria of the genus Azotobacter, the activity of enzymes (catalase and dehydrogenases), and the phytotoxicity indicators decrease. The degree of reduction in biological properties depends on the silver concentration in the soil and the period from the contamination moment. In most cases, there is a direct relationship between the silver concentration and the degree of deterioration of the studied soil properties. The silver toxic effect was most pronounced on the 30th day after contamination. In terms of their resistance to silver pollution, the studied soils are in the following order: ordinary chernozem > sierosands ≥ brown forest soil. The light granulometric composition of sierosands and the acidic reaction of the environment of brown forest soils, as well as the low content of organic matter, contribute to high mobility and, consequently, high ecotoxicity of silver in these soils. The regional maximum permissible concentration (rMPC) of silver in ordinary chernozem (Haplic Chernozems, Loamic) is 4.4 mg/kg, in sierosands (Haplic Arenosols, Eutric) 0.9 mg/kg, and in brown forest soils (Haplic Cambisols, Eutric) 0.8 mg/kg.