Metabolism of [14C]acrolein (Magnacide H herbicide): nature and magnitude of residues in freshwater fish and shellfish

Acrolein, an aquatic herbicide, is applied as MAGNACIDE H herbicide directly into the water of irrigation canals at concentrations of 1 to 15 ppm. Two representative freshwater fish species, the bluegill sunfish (Lepomis macrochirus) and the channel catfish (Ictalurus punctatus), and two representative freshwater shellfish species, a unionacean clam (Elliptio complanata) and the northern crayfish (Orconectes virilis), were exposed separately to two applications of [14C]acrolein, with 7 d between the two dosings. The nominal water concentrations were 0.02 and 0.1 ppm acrolein for fish and shellfish, respectively. Exposures were terminated 1 d after the second application. Metabolites were identified from the edible tissues of each test species: there was very little similarity in the metabolism of acrolein between them. The most notable observation was that acrolein was never detected in any of the tissues sampled. Glycidol, glycerol, 1,3-propanediol, and glyceric acid were the major metabolites found in the catfish, crayfish, bluegill, and clams, respectively. This study demonstrated that these test species, when exposed under static conditions to [14C]acrolein, are able to metabolize the parent compound and its residues in their edible tissues. The metabolism of [14C]acrolein so rapid in the edible tissues of these species that neither acrolein nor its major oxidative and reductive metablites, acrylic acid and allyl alcohol, respectively, were detected