Absolutely, and they need to be recycled properly, I'll give you my address and I'll take care of them for you.
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.