SUMMARY
The object of research is the products of the condensation reaction of phenol, formaldehyde and sodium sulfite in an aqueous medium, in order to obtain water-soluble non-toxic products based on it, which can be proposed for use as surfactants. In the course of the study, the effect of the reaction conditions (ratio of components, temperature and process time) on the quality of the products obtained and their toxicological characteristics are studied. The optimal ratio of the starting reagents phenol: formaldehyde: sodium sulfite: water is selected, which allows to obtain a product with surface-active properties and which contains substances that can be harmful to health. It is recommended that the condensation process be carried out within 1 hour, the optimum reaction temperature is selected at 130 °C. The qualitative characteristics of the obtained product allow to recommend its use as an anionic surfactant. For this, the symptomatic and toxicological properties of the newly developed surfactant, the product of the condensation of phenol, formaldehyde and sodium sulfite in an aqueous medium, are studied. Based on the studies, it is found that with the introduction of such surfactants into the stomach of experimental white rats-females, their slightly irritating effect on the mucous membranes and skin is observed. According to the mortality criterion, with a single oral administration (LD50), the harmful effects of the substance on rats are not noted. According to the research results, the product can be attributed to class IV hazard (low hazard substances) according to GOST 12.1.007.According to toxicological findings, the resulting product can be recommended for use as a textile auxiliary substance, in the technological operations of bleaching, dyeing and printing of fabrics in contact with human skin, as well as additives to concrete mixtures used in the construction industry and other industries