Safe to give store-bought "trout" worms?

We over-bought "trout" worms for a fishing outing. Now I've got 90 "trout" worms in my fridge in little blue boxes.

Are these safe to give my 5 wk old chicks? They love the spiders we've been offering from the yard (mostly young wolf spiders) and tried to eat the very large june-bug we found today (no luck, too big to fit in beak)....but haven't tried a worm yet.

Is it safe? (I figure earthworms from the yard must be, we've got enough robins to fill the state!)

Thanks!