Abstract: The present study aimed at comparing the toxicity of the conventional formulation of the lambda-cyhalothrin (LC) insecticide (Karate®, Syngenta) and the formulation of the nanoencapsulated insecticide (Karate Zeon®, Syngenta) on soil invertebrates (Folsomia candida and Eisenia fetida) and terrestrial plants (Zea mays, Lactuca sativa and Solanum lycopersicum). For this purpose, independent standard toxicity assays were carried out in an artificial soil contaminated with different concentrations (5.8 to 68.0 mg LC/kg(soil dw) of the selected pesticides, following protocols of the Organization for Economic Cooperation and Development (OECD) and the International Organization for Standardization (ISO). The results showed a highest ability of both formulations to inhibit the reproduction of E. fetida, whereas only the formulation containing the nanoencapsulated LC inhibited the reproduction and caused a high mortality in the collembolans F. candida. In addition, the nanoencapsulated insecticide inhibited the germination of S. lycopersicum and L. sativa. No toxic effects on germination and growth of Z. mays were recorded. Although the use of nanopesticides can contribute for a more sustainable production of food, it is of utmost importance to perform more detailed and accurate toxicological assessments of pesticide-containing nanomaterials to predict and ensure the safety of these new chemical entities for the environment and human health.