PW08 Ecotoxicity and Environmental Chemistry of Antibiotics
Exhibit Hall
8:00 AM - Wednesday, 12 November 2003
(PW135) Comparison of biodegradation kinetics of sulfonamides (sulfamethazine, sulfamethoxazole, and sulfathiazole) in a lab-scale bioreactor.
Pérez, S1, Aga, D1, 1 State University of New York at Buffalo, Buffalo, New York, USA
ABSTRACT- Water bodies are impacted by a great variety of organic contaminants. A relevant group are antibiotics that are released into the environment by different pathways (animal and human excretion, aquaculture and waste from pharmaceutical production). Even small amounts of the antibiotics may have ecotoxicological effects, because they can enhance the occurrence of resistant bacteria in different environments. One of the most widely used groups of antibiotics in animal husbandry are sulfonamides, which are synthetic antimicrobials. Presently, sulfonamides are used in farm animal feedstuff and fish cultures as veterinary drugs for prophylactic and therapeutic purposes. In this study, we focused on the determination of the biodegradation kinetics of selected sulfonamides (sulfamethazine, sulfamethoxazole, and sulfathiazole) because these are the most frequently detected sulfonamides in river waters. There are limited data available on the degradability of these antibiotics in the aquatic environment. Therefore, we used a laboratory-scale bioreactor to simulate biodegradation in environmental conditions. The target compounds were spiked separately as well as in combination concentrations, that are environmentally relevant, to the test medium in order to compare their primary degradation. Tentative identification of biodegradation intermediates was performed with Liquid Chromatography-Ion Trap-Mass Spectrometry.
Key words: sulfonamides, antibiotics, biodegradation, LC-MS