TP5 Ecotoxicity and Environmental Chemistry Antibiotics
Room 17A/B, Level 4
2:10 PM - 5:30 PM, Tuesday, 11 November 2003
Chair: Aga, Diana ,
(287) Occurrence, fate, and impact of antibiotics in hospital and municipal wastewaters and in rivers in Switzerland.
Kohler, H.-P-1, Alder, A.1, Golet, E.1, Kuch, H.1, McArdell, C.1, Molnar, E.1, Anh Pham Thi, N.1, Giger, W.1, 1 EAWAG, Swiss Federal Institute of Environmental Science and Technology, Dübendorf, CH, Switzerland
ABSTRACT- Antibacterial agents used in human medicine can reach aquatic environments via waste-waters from hospitals and communities. This study aims at assessing the environmental exposure for some widely used antibiotics. Analytical methods were established for fluoroquinolones, macrolides, and 
-lactams. Seven penicillins and four cephalosporines were used for method development. It became particularly evident that quantitative determinations in hospital wastewaters have to be based on calibrations in very similar sample matrices, e.g. in treated wastewater effluents. Studies in the Glatt River watershed revealed that clarithromycin, the main degradation product of erythromycin-H2O and roxithromycin occurred ubiquitously in treated municipal wastewaters and in the Glatt River. Maximum clarithromycin concentrations of 330 ng/L were found in wastewater effluents, whereas in the river the concentrations ranged from 5 to 75 ng/L. Mass flux calculation revealed that the loads of the most abundant clarithromycin were reduced in the river to about 50%. The second emphasis was on hospital wastewaters. The following antibiotics were quantitatively determined: ciprofloxacin, norfloxacin, clarithro-mycin, erythromycin-H2O, roxithromycin. A good correlation was found between consumption data and concentrations measured in the hospital wastewaters. Although the -lactam antibiotics could not yet be fully quantified, eleven of these chemicals could be detected in hospital wastewaters.
Key words: hospital wastewaters, fate of antibiotics, erythromycin, -lactams