Put them in the washing machine and turn it on....
Just never enter a club with UV lights with them on. Unless you're hoping to garner a pity fuck out of them or something.
If this option is too "easy" for you, then I suggest you throw them out. buy a new pair of favourite pants and remember to take them off the next time you decide to knock on out in the bathroom of the AA meeting. Or at least take off a sock and splooge into that or something. I mean come on, it's not like we're 13 anymore buck up your ideas!