Nitrosation of quaternary ammonium compounds in vivo in the Wistar rat

1. Animals dosed orally with nitrite (1.5 × 10^?3 mol/kg) and nonyl dimethylbenzylammonium bromide (2.9 × 10^?4 mol/kg) exhibit liver damage within two hours; cetyl trimethylammonium bromide plus nitrite was not significantly hepatotoxic.

2. Both nonyl dimethylbenzyl ammonium bromide and cetyl trimethylammonium bromide were demethylated by rat-liver microsomal preparations; substrate concentrations of 1 mM or more were inhibitory.

3. Bile from rats given i.p. doses of cetyl trimethylammonium bromide, nonyl dimethylbenzylammonium bromide or dodecyl dimethylbenzylammonium bromide contains only metabolites, no unchanged compounds were detected.