1-14C-n-hexadecane disposition in the spiny lobster, Panulirus argus and the American lobster, Homarus americanus.

1-14C-n-hexadecane, a model compound for the non-volatile aliphatic hydrocarbon components of crude oil, was administered by intrapericardial injection to the spiny lobster, Panulirus argus, and the clawed or American lobster, Homarus americanus. Experiments were conducted in Florida (spiny lobster) and Maine (American lobster). The animals were sacrificed at various times from 0.5 hr to 8 wks after administration of the dose. The tissues and fluids were analyzed for 14C content by digestion or catalytic oxidation and liquid scintillation counting. Selected tissues (hepatopancreas, tail muscle and hemolymph) were extracted with ethyl acetate to allow quantitation of the unmetabolized n-hexadecane by thin layer chromatography. n-Hexadecane-derived radioactivity was very persistent in both the spiny lobster (t1/2 = 4.6 wk) and the American lobster (t1/2 = 11.2 wk). In both lobsters, the hepatopancreas (HP) acquired the highest specific activity and the tail muscle had the longest half life for elimination from an individual tissue. Although hexadecane was metabolized more rapidly in the HP of the spiny lobster than in the HP of the American lobster, unmetabolized hexadecane persisted in the HPs of both species for at least 8 weeks after the dose (the longest time studied).