Babies are known to have bad reactions to chemical residue/odor. Even very little of it. I've seen them "spaz out" after being put in plastic containers that once had bleach in it even though the containers were rinsed thoroughly. One possibility is that the snakes had mites on them, and the mites "spazzed out" causing them to do the same. I know that dogs do this when the fleas on them react to products such as Frontline. You say you lost some? Does that mean they died? Must have put them back too soon and they got poisoned. Like I said, babies are much more sensitive than adults.