title: Photodegradation of sulfonamide antibiotics in simulated and natural sunlight: implications for their environmental fate.
abstract: The photochemical fate of seven sulfonamides was investigated in matrices representative of natural water bodies under various light sources. Fundamental photolysis parameters such as molar absorption coefficient, quantum yield (QY) and first-order rate constants were determined. The photolysis decay rate was dependent on the protonation state of the molecule, pH of the water sample and dissolved organic matter. Natural organic matter was the most significant factor in the indirect photolysis of sulfonamides. Half-lives were in the range of minutes at 254 nm to days under natural sunlight. Under natural sunlight, all sulfonamides showed higher removal rates in natural waters implying that indirect photolysis is the predominant mechanism.
authors.affiliation: a Department of Chemistry and Biochemistry , Florida International University , Miami , Florida , USA.
authors.forename: Sudha Rani
authors.initials: SR
authors.lastname: Batchu
authors.forename: Venkata R
authors.initials: VR
authors.lastname: Panditi
authors.forename: Piero R
authors.initials: PR
authors.lastname: Gardinali
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry*; D006207:Half-Life; D007700:Kinetics; D010782:Photolysis / Q000528:radiation effects*; D000077145:Sulfanilamide; D013424:Sulfanilamides / Q000737:chemistry*; D013472:Sunlight; D014874:Water Pollutants, Chemical / Q000737:chemistry*
chemical_list: D000900:Anti-Bacterial Agents; D013424:Sulfanilamides; D014874:Water Pollutants, Chemical; D000077145:Sulfanilamide