Quickstep, you don't say what brand or kind they are, what material they are. The washing care will vary. If there's no care tag that came with them, I would suggest calling the maker, or telling us what they are made of. If they are "plastic" or "breathable water resistant" everything is different.
Odds are the stink can be easily washed out, unless it is the "barf" smell that uncured cheap plastic sometimes gets as it ages. That's forever, the result of the plasticizers leaking out or breaking down.