Tissue disposition and excretion of 14C-labelled aflatoxin B1 after oral administration in channel catfish.
The pharmacokinetics, tissue distribution and excretion of 14C-labelled aflatoxin B1 (AFB1) were examined after oral administration (250 micrograms/kg body weight) in channel catfish (Ictalurus punctatus). Plasma concentrations of parent AFB1 were best described by a one-compartment pharmacokinetic model, in which peak plasma concentration (503 ppb) occurred at 4.1 hr after dosing. The absorption and elimination half-lives were 1.5 and 3.7 hr, respectively. AFB1 was highly bound (95%) to plasma proteins. Concentrations of 14C (in AFB1 equivalents) measured in the tissues were highest at 4 hr, ranging from 596 ppb in the plasma to 40 ppb in the muscle. AFB1 residues were rapidly depleted; at 24 hr the concentrations in the plasma and muscle were 32 and less than 5 ppb, respectively. Concentrations in the bile exceeded 2000 ppb (at 24 hr), whereas the highest concentration in the urine was 51 ppb (4-6-hr collection interval). Renal and biliary excretion accounted for less than 5% of the administered dose, indicating incomplete absorption. Pharmacokinetic modelling and tissue data demonstrate a very low potential for the accumulation of AFB1 and its metabolites in the edible flesh of channel catfish through the consumption of AFB1-contaminated feed.
Plakas
S M
SM
Division of Seafood Research, Food and Drug Administration, Dauphin Island, AL 36528.
Loveland
P M
PM
Bailey
G S
GS
Blazer
V S
VS
Wilson
G L
GL
D000284:Administration, Oral; D016604:Aflatoxin B1 / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics* / Q000652:urine; D000818:Animals; D002851:Chromatography, High Pressure Liquid; D007059:Ictaluridae; D012588:Scintillation Counting; D013056:Spectrophotometry, Ultraviolet; D014018:Tissue Distribution
D016604:Aflatoxin B1