UV rays is another one of those debatable issues.

The sun bombards outdoor plants with UV rays, so, whats to say anything is wrong with them?

If I were you, I Would...

1. Remove the dome. What are you protecting them from? Remove the threat.
2. Get a fan on those blowing across the seedling tops right now. You'll thank yourself later.

A little circulation in the set up will do wonders for your grow.

Domes are good for clones for a bit....but just not needed for seedlings.

Get them expose to the environment now.

Lose the dome...