In recent decades, food safety in developed countries has not been threatened by food shortages but by possible contamination with numerous toxic substances. While for classical pesticides and contaminants standards are imposed to ensure that they have no observable effects, the presence of contaminants from unexpected sources has recently come to the fore. Thus, "biopesticides" and traditional procedures are used in organic farming and the food industry that have not been fully investigated and validated using current scientific knowledge. They are supposed to have no negative effects on human health, but recently it has been shown that the most toxic known substances are of natural origin. Also during improper storage of food, micro-organisms can develop that produce toxins or allergens. Also during food preparation using inappropriate recipes toxic substances can be produced (PAHs during smoking using too high temperatures, acrolein by fat burning). The objectives of the project are to identify substances with unknown toxic effects that may be found in food or the environment and to develop biosensors to analyse these new toxins. The toxic substances will be identified by studying the in vitro biochemical properties of a set of potentially hazardous substances identified from the literature as used/produced in the food industry. After the identification of new toxic compounds, biosensors for their rapid analysis will be developed. If technically feasible, the detection principle of the biosensors will be based on the mode of action of the toxins (quantification of enzyme inhibition, DNA interaction study for genotoxicity). Immunosensors will be developed for other mechanisms of action. Another result of this project is the possibility of scientific confirmation of the lack of toxicity of suspected substances.