Absolutely, and they need to be recycled properly, I'll give you my address and I'll take care of them for you. :-D
Kidding aside, if you have any concern, you could pressure wash and/or soak them in a bleach solution to clean. Leaving them out in the sun also has it's benefits.
I know some folks have permacomb that is decades old and still in use.
Personally I have some that are going on 3 years old and I have no plans on doing anything with them. Unless a hive dies out for disease or an unknown reason, I wouldn't be too concerned, especially if you aren't treating with hard chemicals.