Soil is a non-renewable resource subjected to a series of degradation processes and increasing environmental pressure, driven or exacerbated by human activity. As the appropriate functioning of the soil is essential for terrestrial ecosystems and human activity the risk of its impairment should be taken very seriously. Among numerous pollutants present in the environment, pesticides, due to their wide and common usage and impact on non-target organisms, represent one of the major soil pollutants. More recently nanoparticles (NPs) have been brought into focus as the increased interest for their usage in agriculture highlights the importance of understanding its ecotoxicological effects. The proposed project aims to identify the various effects of NPs and pesticides mixtures on non-targeted soil organisms, but also to identify the interactions of metal-based NPs and pesticides. In order to deliver the specified objectives of the project we propose a comprehensive ecotoxicological research which includes various levels of complexity (from preliminary laboratory to semi-field experiments), different endpoints (from molecular to population level), different exposure scenarios (single-mixture, short-long, single application-sequence of applications) and inclusion of both model and native soil organisms. Additionally, based on experimental data on toxic effects of selected pesticides and metal-based NPs, population-level matrix models will be constructed. From the model outputs the effects of investigated toxicants will be assessed and used to establish under which set of conditions a modelled population will respond to applied toxicants and alter its potential to respond to other stressors. The expected results will improve the state of knowledge on toxicity of mixtures on non-targeted soil organisms and can be implemented in risk assessment process. Consequently, expected results can enhance soil protection and soil ecological sustainability.