Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

The effects of smoltification on the distribution, metabolism and elimination of benzo[a]pyrene in juvenile coho salmon, Oncorhynchus kisutch

Conference ·
OSTI ID:398229
;  [1]
  1. Simon Fraser Univ., Burnaby, British Columbia (Canada). Dept. of Biological Sciences
The activities of Phase 1 and Phase 2 biotransformation enzymes in the livers of yearling coho salmon (Oncorhynchus kisutch) were determined bi-weekly beginning in February until release from the hatchery in mid June, in order to observe alterations in baseline levels during smoltification. Peak activities occurred in February and March and then declined, Cytochrome P450 levels ranged from 5.27 {+-} 0.34 to 0.83 {+-} 0.29 nmol/g liver, EROD activities ranged from 352.19 {+-} 24.35 to 81.04 {+-} 11.63 pmol/min/g liver, and glutathione S-transferase activities ranged from 11.07 {+-} 0.377 to 3.77 {+-} 0.64 mmol/min/g liver. The whole body excretion {sup 3}H-benzo[a]pyrene (B[a]P) was examined following i.p. injection during this same period. A trend towards increased B[a]P retention occurred from February to April and then declined until June. The bile contained the largest amount of b[A]P-derived radioactivity per gram tissue weight, followed by the liver, kidney and fat. Bile analysis revealed that 55--63% of the radioactivity were Phase 1 metabolites. The remaining radioactivity detected was 16--24% glucuronide conjugates, 8% sulfate conjugates, 7% other organic conjugates and 6% aqueous-soluble metabolites. These findings suggest that the transformation from freshwater adapted coho parr to smolts significantly alters biotransformation enzyme activities and the distribution and elimination of xenobiotics such as benzo[a]pyrene.
OSTI ID:
398229
Report Number(s):
CONF-9511137--; ISBN 1-880611-03-1
Country of Publication:
United States
Language:
English