VITAMIN-A STORES, TERATOGENESIS, AND EROD ACTIVITY IN WHITE SUCKER, CATOSTOMUS-COMMERSONI, FROM RIVIERE-DES-PRAIRIES NEAR MONTREAL AND A REFERENCE SITE

White sucker, Catostomus commersoni, were sampled from the Riviere des Prairies in the vicinity of Montreal and the upper reaches of the Ottawa River in La Verendrye Park (reference site). Riviere des Prairies fish had lower liver retinol (p less than or equal to 0.0001) and retinyl palmitate (p less than or equal to 0.0001) concentrations than fish from the reference site. Riviere des Prairies females and males contained only 9.3 and 30%, respectively, of the vitamin A stores detected in reference fish. Age was an important variable. Covariance analysis revealed that the the rate of retinyl palmitate storage with age was higher (p less than or equal to 0.0001) for sucker at the reference site. Retinaldehyde was the major retinoid in eggs; however, concentrations were not different between the two sites. The prevalence of malformations was 1.49% among Riviere des Prairies larvae, greater (p less than or equal to 0.002) than that of the reference group. Eye deformities (i.e., anophthalmia, synopsia) were 11.8 times more prevalent in the Riviere des Prairies larvae. Ethoxyresorufin-O-deethylase (EROD) was greater (p less than or equal to 0.0003) in the Riviere des Prairies fish. Liver EROD activity in adult females was positively correlated (R = 0.81; p less than or equal to 0.0004) with the prevalence of deformities of their progeny. Semiquantitative results showed that embryo mortality also tended to increase with EROD activity.