UV-C photolysis of endocrine disruptors. The influence of inorganic peroxides.
Norfloxacin, doxycycline and mefenamic acid have been photolysed with UV-C radiation (254 nm) in the presence and absence of inorganic peroxides (hydrogen peroxide or sodium monopersulfate). Quantum yields in the range (1.1-4.5)x10(-3) mol Einstein(-1) indicate the low photo-reactivity of these pharmaceuticals. Inorganic peroxides considerably enhanced the contaminants conversion, although no appreciable mineralization could be obtained. A simplistic reaction mechanism for the hydrogen peroxide promoted experiments allowed for a rough estimation of the rate constant between hydroxyl radicals and norfloxacin (k>1 x 10(9)M(-1)s(-1)), doxycycline (k>1.5 x 10(9)M(-1)s(-1)) and mefenamic acid (k>11.0 x 10(9)M(-1)s(-1)).
Rivas
Javier
J
Departamento de Ingeniería Química y Química Física, Facultad de Ciencias, Avenida de Elvas S/N, 06071 Badajoz, Spain. fjrivas@unex.es
Gimeno
Olga
O
Borralho
Teresa
T
Carbajo
Maria
M
D004318:Doxycycline / Q000737:chemistry*; D052244:Endocrine Disruptors / Q000737:chemistry*; D007700:Kinetics; D008528:Mefenamic Acid / Q000737:chemistry*; D009643:Norfloxacin / Q000737:chemistry*; D010545:Peroxides / Q000737:chemistry*; D014466:Ultraviolet Rays
D052244:Endocrine Disruptors; D010545:Peroxides; D008528:Mefenamic Acid; D009643:Norfloxacin; D004318:Doxycycline