in tissues and measures of bioeffects between sites in the bay, they also observed sufficient 

 within-site variability to suggest that all the fisli from any one site were not from a distinct 

 population with identical histories of contaminant exposure. 



An assortment of natural environmental factors and biological variables can influence 

 within-site variability in the fish bioeffects measures. They could include genotype, gender, 

 degree of maturation, stress preceding capture, stress during capture, and feeding success. Any 

 combination of these and other factors may have contributed to the variability among fish 

 within the sampling sites. 



Coefficients of variation in the biological measures performed on fish caught at each 

 site in November and December differed among the measures (Table 38). The measures of 

 total and attached micronuclei had high within-site variation. The analysis for 

 cytochrome P-450E/mg protein also indicated relatively high variation. The coefficients of 

 variation for testosterone, estradiol-2-hydroxylase/mg protein, total cytochrome P-450/mg 

 protein, EROD/mg protein, and AHH with 7,8-BF were relatively small at most sites. 

 Based upon data in Table 31, the chemical data from the BK and SP sites were the least 

 variable. However, there was no apparent pattern of lower within-site variation in the 

 biological measures in the fish from those two sites. 



The maximum and minimum site means, the total range in mean values, the average of 

 the SDs, the average of the CVs, and the quotient of dividing the range by the average SD 

 are listed in Table 39. The average CVs were highest for the end-points of attached and 

 total micronuclei and cytochrome P-450E and lowest for total cytochrome P-450 and estradiol- 

 2-hydroxylase/mg protein. The quotients of total range over the average SDs were highest 

 for EROD/mg protein and EROD/nmol P-450. By comparison, these values were relatively 

 low for total P-450, attached micronuclei, and AHH following exposure to 7,8-benzflavone. 



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