Investigation of the behavior of benzalconium chloride biocide in chloridated waters and identification of its derivatives

• Grant number: 18/18106-3
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: October 01, 2018
• End date: September 30, 2019
• Field of knowledge: Engineering - Sanitary Engineering - Water Supply and Wastewater Treatment
• Principal Investigator: Renata Colombo
• Grantee: Letícia Bezerra da Silva
• Host Institution: Escola de Artes, Ciências e Humanidades (EACH). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Biocides are active ingredients of various commercial products that have the function of combating unwanted living organisms such as fungi, bacteria and insects. The increased use of these products has led to the continuous disposal of biocides in the environment leading to contamination of the soil and especially of the waters. One of the biocides that is present in the composition of several products, used in large scale and for different applications, is benzalkonium chloride. This biocide, besides being detected as a micropollutant in the aquatic system, is reactive to the chlorine-free species, present in the natural environment and in the supply waters, favoring the formation of contaminants derived from them. Data on the behavior of these micropollutants, as well as their derivatives, on the environment and human health are still scarce. Regulatory agencies in Brazil and in the world have required studies that may support more specific and safe regulations of this class of substances. Thus, in this project we propose an investigation of the behavior of benzalkonium chloride, under different environmental conditions, focusing on chlorinated aquatic environments. This substance will be subjected to the conditions of pH, light, temperature and chlorine concentration usually present in the natural environment and/or applied during the treatment and distribution of water supply. Analytical methodologies will be developed to monitor the behavior of this substance and to identify derivatives eventually formed. To date, no national or international studies involving the investigation of this biocide and its derivatives have been found under the conditions proposed in this project.