Ecological Systems and Devices Annotation << Back DETERMINATION OF PHENOLS IN NATURAL URBANIZED AND BACK-GROUND WATERS TERRITORY OF RUSSIA N.N. Roeva, S.S. Voronich, I.A. Zaytseva, N.S. Voronich, O.A. Zaytseva Phenol and phenolic compounds are inherent in nature, these substances appear in ecosystems as a result of metabolic processes of aquatic organisms, higher plants, during the biochemical decomposition of organic matter in the water column. A number of organisms are capable of synthesizing phenol in response to an insect attack, injury or ultraviolet irradiation. In addition, phenol can enter surface reservoirs as part of wastewater discharged by petrochemical and oil refi neries; production of building materials, rubber, adhesives, plastics, pesticides, phe-nol-formaldehyde resins; pulp and paper mills. The presented article considers the main methods for determining monatomic phenols of various concentrations: titrimetric, based on their bromination when separated from the sample by distillation with water vapor and spectrophotometric method using n-nitroaniline as an organic reagent with the formation of complex compounds of yellow or yellow-brown color in an alkaline medium depending on the determined concentrations of phenols; as well as the results of the author's studies of the content of phenols in the natural waters of the Moscow and Ryazan regions. Keywords: Natural waters; pollutants; phenol; urbanized territories; titrimetry; spectrophotometry; research. DOI: 10.25791/esip.1.2022.1277 Pp. 10-14.