i'd put them in another box, like i said, one with screened bottom, coz the sugar doesn't kill varoa, it just causes it to fall of, now if you let varoa fall on the bottom, they'll just crawl back up on the bees. i don't think it would be the best idea to put bees all upset into the hive but i don't know, maybe it would be ok
btw, i said a pound of sugar just as a matter of speaking a pound might be a bit too much :)