Does vodka contain sulfites

Apparently, yes, under certain circumstance there may be some sulphites in whisky*. The issue got a lot of attention when a famous whisky critic called Michael Jackson (not the late king of pop) started fuming about foul sulphurous tastes in spirits matured in particular barrels a few years ago. I'm sure you know that scotch whiskies are matured in 'second-hand' barrels that are imported from the U.S. (Bourbon barrels) or Spain (sherry barrels). Jackson's explanation for the infuriating phenomenon was that some of these barrels were being disinfected using sulphurous smoke (to prevent mould etc.), and that this left the barrels with a terrible taste subsequently transferred to the whisky put into them.

*When referring to the spirit distilled in Scotland the only correct spelling is whisky (without the 'e'). The U.S. and Irish versions are known as whiskey. There is no spelling that includes both drinks so I use the former version for convenience here, although the issue I discuss involves both types.