Insecticides are pesticides, broad-spectrum compounds used against insect, arthropod, other pest and fungi that are highly toxic to humans by different routes of exposures, such as dermal absorption, ingestion or inhalation. Insecticides are a group of pesticides used in agriculture to control plant diseases caused by fungal attack. As a result of their relative persistence, insecticides residues present in water, food, animals etc., represent a risk for human health. Due to their widespread presence and toxicity, an environmental monitoring is required to protect the public from possible organic toxins released into the air, soil, and water. All these aspects have the need to develop toxicity methodologies, structured-toxicity relationships and biological activity. Aim The aim of this study was to correlate the eco- toxicity resulted by the biodegradation of some organophosphorus insecticides with characteristics of these compounds, using FAF-Drugs3 program in the QSTR-quantitative structure toxicity relationships model.