PARENT SESSION

PM15 Biomarkers
Exhibit Hall
8:00 AM - Monday

(PM233) Comparison of new and existing methods for measuring estrogenic activity in fish.

Arijs, K.¹, Versonnen, B.¹, Maes, H.¹, Noppe, H.², De Brabander, H.², Janssen, C.¹, ¹ Laboratory of Environmental Toxicology and Aquatic Ecology, Ghent University, Gent, Belgium² Laboratory of Chemical Analysis, Ghent University, Merelbeke, Belgium

ABSTRACT- Juvenile rainbow trout (Oncorhynchus mykiss) were exposed to 1-10-100 ng 17-ethinylestradiol (EE2)/l (nominal concentrations) for 14 days in a semi-static experiment. Different methods were applied to determine the subsequent estrogenic activity in these fish. Total protein and vitellogenin concentration (protein electrophoresis) in surface mucus were used as non-destructive measures for the estrogenic activity. Plasma vitellogenin concentration was measured using total protein content, protein electrophoresis and ELISA. A yeast estrogenic screen (YES) with Saccharomyces cerevisiae was used to determine the estrogenic activity in the bile after glucuronidase treatment. Furthermore, gonadosomatic indices (GSI), hepatosomatic indices (HSI) and condition factors of the rainbow trout were recorded. The quantification of 17-ethinylestradiol in water samples taken at different time intervals between two test solution renewals was performed with GC-EI-MS² and was compared to quantification with the YES. The results of the different methods were compared and cost-effective alternatives to the ′classical′ methods for estrogenic activity measurement in fish are discussed. The lowest observed effect concentration (LOEC) after 14 days of exposure was 10 ng EE2/l with all of the used test methods. Determination of vitellogenin in surface mucus and the estrogenic activity in bile were very well suited and cost-effective for measuring estrogenic activity in fish. Good correlations between ′new′ and ′classical′ methods were found.

Key words: vitellogenin, rainbow trout, surface mucus, bile