Chlorination and oxidation of sulfonamides by free chlorine: Identification and behaviour of reaction products by UPLC-MS/MS. (15th January 2016)

• Record Type: Journal Article
• Authors: Gaffney, Vanessa de Jesus; Cardoso, Vitor Vale; Benoliel, Maria João; Almeida, Cristina M.M.
• Is Part Of: Journal of environmental management. Volume 166(2016)
• Page Start: 466
• Page End: 477
• Publication Date: 2016-01-15
• Subjects: Sulfonamides -- Chlorination -- Chlorination by-products; Environmental policy -- Periodicals; Environmental management -- Periodicals; Environment -- Periodicals; Ecology -- Periodicals; 363.705
• DOI: 10.1016/j.jenvman.2015.10.048
• Languages: English
• ISSNs: 0301-4797

Abstract

Abstract: Sulfonamides (SAs) are one class of the most widely used antibiotics around the world and have been frequently detected in municipal wastewater and surface water in recent years. Their transformation in waste water treatment plants (WWTP) and in water treatment plants (WTP), as well as, their fate and transport in the aquatic environment are of concern. The reaction of six sulfonamides (sulfamethoxazole, sulfapyridine, sulfamethazine, sulfamerazine, sulfathiazole and sulfadiazine) with free chlorine was investigated at a laboratory scale in order to identify the main chlorination by-products. A previously validated method, liquid chromatography/mass spectrometry, was used to analyse SAs and their chlorination by-products. At room temperature, pH 6–7, reaction times of up to 2 h and an initial concentration of 2 mg/L of free chlorine, the majority of SAs suffered degradation of around 65%, with the exception of sulfamethoxazole and sulfathiazole (20%). The main reaction of SAs with free chlorine occurred in the first minute. Graphical abstract: Highlights: Study evaluated the impact of chlorination on sulfonamides. The disinfection conditions were similar to those used in water treatment plant. Removal efficiencies of sulfonamides were determined. The UPLC-MS/MS method was useful in identifying new compounds, chlorinated or not. Further assays are needed to characterize the toxicity of these new compounds.