Have you actually checked to see if the smack is still in there? It might be completely washed away. If you used a really harmful washing powder or something it would probably be best you don't snort it, and especially don't inject it. Just look on the back of the box, look at the ingredients, and look them up to see how harmful they are, and if they're not too bad, I guess you could sniff it, but that's really bad advice to be honest. The detergent might have also reacted with the heroin (especially if it was a hot wash), but I think it would just change the salt at the most. It might be a salt with a low intranasal bioavailability or something, idk, anyway, if you decide to salvage it put it on a plate with a lamp above it, it'll dry out after a while