|
(344) Fluoroquinolone Antibacterial Agents: Occurrence and Behaviour in Municipal Waste Water Treatment. Golet, Eva1, Xifra, Irene1,2, Alder, Alfredo1, Giger, Walter1, 1 2 ABSTRACT- In the last few years, public and scientific concern on the environmental relevance of trace amounts of pharmaceuticals in ambient waters has continuously increased. Until now it is not clear whether the presence of trace concentration of these active compounds in the aquatic environment may pose a risk for aquatic organisms. A major concern is the potential emergence and spread of drug-resistance due to antibiotics in ambient waters. Environmental exposure was studied for the compound class fluoroquinolones (FQs). FQs are among the most important antibacterial agents (synthetic antibiotics) used in human and veterinary medicine world-wide. In Switzerland for instance, FQs contribute approx. 15% of the total amount of antibiotics consumed. Because metabolization rates of FQs are typically less than 25%, an important percentage of the administered drug is excreted mainly via urine as the parent compound. We focused on evaluating the occurrence of these antibacterial agents in effluents of several municipal waste water treatment plants in Switzerland. The aim was to better understand the behaviour of FQs during waste water treatment and to assess their inputs in ambient waters. Quantitative determinations were performed by solid-phase extraction on mixed phase cationic exchange disk cartridges and reversed-phase liquid chromatography with fluorescence detection. The two most abundant human-use FQs, ciprofloxacin and norfloxacin, were found at trace residual concentrations in mechanically treated effluents (250 - 405 ng/L) and biologically treated effluents (45 - 120 ng/L). Therefore, although a relatively efficient elimination during the treatment process occurs (70-80%), ciprofloxacin and norfloxacin are emitted into ambient surface waters. Key words: fluoroquinolones, antibiotics, waste water, analysis |
