Uptake, disposition, and elimination of acrylamide in rainbow trout

The uptake, disposition, and elimination of [2,3-14C]acrylamide was studied in fingerling rainbow trout exposed to 0.388 and 0.710 mg/liter [2,3-14C]acrylamide at 12 degrees C under static water conditions for 72 hr. 14C in carcass and viscera was determined at times ranging from 4 to 72 hr after the beginning of the exposure period and 4 to 96 hr after transfer of the fish to fresh flowing water for the elimination studies. Uptake of 14C was initially rapid and plateaued after 72 hr of acrylamide exposure. No appreciable bioaccumulation occurred in carcass or viscera at either exposure concentration and 14C distributed approximately equally to all tissues studied. Elimination of 14C from carcass and viscera was biphasic with a terminal half-life of approximately 7 days. 14C elimination was not uniform in all tissues studied with the most rapid elimination occurring in blood and gill and the slowest elimination occurring in muscle and intestine. In addition, 10 to 15% of the initial total 14C in carcass or viscera was nonextractable and was associated with the protein fraction of the sample at all time points in the depuration period. Approximately 20% of an ip administered dose of [14C]acrylamide was eliminated via the gills, 7% via the urine, and less than 1% via the bile in 2 hr. At least three biliary metabolites were isolated by HPLC.