STATISTICAL-ANALYSIS OF CYPRINID ETHOXYRESORUFIN-O-DEETHYLASE DATA INA LARGE FRENCH WATERSHED

A comparison of ethoxyresorufin-O-deethylase (EROD) data collected in 1995 in various sites in the Rhone watershed (France) was carried out to quantify the influence of factors such as contamination and biologi cal parameters on EROD levels and within-group variabilities. Three sp ecies of cyprinids were collected and fish chemical contamination was measured. A log transformation of EROD data provided both normalizatio n and homogeneity of variances. The influence of female sexual maturat ion on the variability and EROD dimorphism was quantified. A relations hip with contaminant bioaccumulation was observed. A comparison with E ROD data collected during previous studies by the same laboratory was made to validate the results. (C) 1998 Academic Press.