@Pam Block posted:
What if regular egg whites were used? They don't say pasteurized.
My comment above holds. There is always some risk of salmonella with raw eggs, and that bacteria will grow more quickly in foods left at room temperature. But if the eggs are not infected with THAT bacteria to start, then THAT bacteria won’t spontaneously arise in it. The icing will set very fast and minimize the risk of other bacterial growth. Always some risk, but the fact is the icing won’t dry or dry properly on cookies if they are refrigerated after icing them.