(p = 0.0011). When expressed in proportion to total P-450 content, the P-450E content was 

 greater in immature OK fish than in mature SP, VJ and RR fish. 



Mean total P-450 content and P-420 content were highest in fish from OK, but there were 

 no significant differences (p = .183 and 0.786, respectively) among sites (Table 32). Also, 

 there were no significant differences (p = 0.385) among sites in percent denatured P-450 

 content. Cytochrome bs content did not differ between RR and OK fish (Mann-Whitney, p = 

 0.756). 



Two-way ANOVA (performed despite the fact that the data were not normally 

 distributed) indicated there were no differences (p = 0.09 to 0.98) in any of the P-450 

 measurements between sites that were attributable to sex. However, both EROD activity 

 and P-450E content/mg protein in immature fish exceeded those measures in mature fish. 



Estradiol 2-hydroxylase activity/mg protein did not differ significantly (p = 0.94) among 

 sites. However, estradiol 2-hydroxylase/nmol P-450 content did differ significantly (p < 

 0.01) among sites (Table 32). The average values were lowest in mature BK fish where 

 cytochrome P-450 induction was among the highest and highest in immature fish from SP. 

 Consistent with this pattern was the observation (Table 30) that estradiol 2-hydroxylase 

 activity in fish injected with BNF was about one-half that in untreated fish. This measure 

 was significantly (p = 0.007) lower in mature females than in immature females. 



AHH activity was generally higher in immature fish than in mature fish. Significant 

 between-site differences in AHH activity were indicated at p = 0.001, but non-parametric 

 S-N-K could not distinguish which sites were different. The mean AHH values in fish in 

 which the samples had been exposed to 7,8 benzflavone were generally one-third to one- 

 fifth those of fish not exposed to this P-450 isozyme inhibitor. 



Estradiol concentration in plasma was not significantly different among sites (p = 0.94) 

 (Table 32). The overall mean value in VJ fish, which were mostly immature, was about one- 

 fifth that in fish from OK which included more matures. Since estradiol suppresses the 

 induction of P-450E, an inverse relationship between estradiol content and P-450E content and 

 EROD activity would be expected. But, this relationship was not obvious with the present 

 data. As would be expected, mature females had higher plasma estradiol concentrations 

 than immatures. Testosterone concentrations also did not differ significantly among sites (p 

 = 0.40) (Table 32). 



Among the fish caught in November and December, the incidence of total counts of 

 micronuclei in blood erythrocytes was significantly different among sites (non-parametric 

 K-W, p = 0.0001). Non-parametric S-N-K indicated that counts were lower in RR than in SP, 

 VJ and BK fish (Table 32). Incidences among the four sites in San Francisco Bay did not 

 differ. Counts of both attached and detached micronuclei were recorded. The incidences of 

 attached micronuclei in all fish did not differ significantly among sites (p = 0.061). 

 However, the incidence of detached micronuclei did differ between sites (p = 0.001) with the 

 same pattern as observed with total counts. The incidence of both forms did not differ among 

 sites in males. However, total incidence and incidence of detached micronuclei were 

 significantly lower in females from RR than in females from three other sites. 



The highest nuclear pleomorphism rating was observed in fish from the Berkeley and 

 Oakland sites (Table 28). There was a significant difference in the incidence of this end- 

 point among fish collected in November-December and January-February from the six sites 

 (X^ = 11.07, p < 0.001). Because of the high frequency of zeros for class 3, classes 2 and 3 

 were combined. Fish from the RR site had the lowest incidence (Table 28). With these fish 

 removed, the incidence was not significantly different at the remaining sites ( X^ = 2.42, df = 

 4, p > 0.50). 



69 



