Three different vitamin E effects, suggestive of specific antioxidant effects, were discovered in the protective action of vitamin E against respiratory decline (a decrease in mitochondrial respiration attributed to a "leakage" of electron transport radicals). No correlation was found between respiraotry decline and random lipid peroxidation. The mechanisms behind two of the three atypical vitamin E effects were defined. Both involve an artifact in the TBA assay for lipid peroxidation. This artifact occurs when TBA assays are carried out in the presence of sucrose and acetaldehyde; the latter is produced from ethanol, the solvent used to add vitamin E to preparations. The artifact in the TBA assay for peroxidations appears also to be responsible for differing interpretations of the hepatotoxic effect of ethanol.