Rapid, dose-dependent elimination of phenol across the gills, and slow elimination of phenyl sulfate in the urine of phenol-dosed lobsters, Homarus americanus.
Although lobsters are known to metabolize lipophilic organic compounds by monooxygenation, little is known of the fate of the hydroxylated metabolites. Single doses of [14C]phenol, 0.019 to 2.8 mg/kg, were administered intrapericardially to groups of lobsters. Hemolymph was sampled serially from appendage joints and analyzed for radioactivity and chemical composition. Separate groups of lobsters were dissected at 0.5, 4, and 24 hr after the 0.1-mg/kg dose to collect urine and tissue samples. Tank water was collected at 0.5 hr and analyzed. Phenol concentrations decreased rapidly in hemolymph (alpha t1/2 = 8.7 min, beta t1/2 = 14.0 min) and part of the dose was excreted through gills into tank water as parent phenol in the first 30 min. The percentage of each dose excreted through the gills increased with increasing dose up to greater than 90% at greater than 2 mg/kg. The phenol that was not excreted through gills was rapidly conjugated with sulfate in the antennal glands and possibly other sites. In both male and female lobsters, phenyl sulfate was eliminated from hemolymph much more slowly than parent phenol. The terminal elimination half-life of phenyl sulfate was slower in females (t1/2 = 11.9 hr) than in males (t1/2 = 6.3 hr). The [14C] present in urine collected 24 hr after the dose consisted primarily of phenyl sulfate (greater than 97%) with traces of phenyl beta-D-glucoside (0.1-3%). Thus, in the lobster, metabolism of phenol to polar conjugates did not enhance elimination from the animal.
Department of Medicinal Chemistry, University of Florida, Gainesville 32610.
M O
MO
James
J D
JD
Schell
M G
MG
Barron
C L
CL
Li
D000818:Animals; D005260:Female; D005880:Gills / Q000378:metabolism*; D006207:Half-Life; D006458:Hemolymph / Q000378:metabolism; D006868:Hydrolysis; D008297:Male; D008121:Nephropidae / Q000378:metabolism*; D010636:Phenols / Q000493:pharmacokinetics*; D011485:Protein Binding; D012623:Seawater / Q000032:analysis; D013463:Sulfuric Acid Esters / Q000652:urine*; D014018:Tissue Distribution
D010636:Phenols; D013463:Sulfuric Acid Esters; C025208:phenylsulfate