[2] Whether fusel alcohol contributes to hangover symptoms is a matter of scientific debate.
A Japanese study in 2003 concluded that "the fusel oil in whisky had no effect on the ethanol-induced emetic response" in the Asian house shrew.
[3] Fusel oil and fusel-oil acetates are used in the lacquer industry as high boiling point solvents.
Some beverages, such as rum, whisky (especially bourbon), incompletely rectified vodka (e.g. Siwucha) and traditional ales and ciders, are expected to have relatively high concentrations of non-hazardous alcohols as part of their flavor profile.
However, in other beverages, such as Korn, vodka and lagers, the presence of alcohols other than ethanol is considered a fault.