Did the person you bought them from treat with chemicals? If not, they are most likely fine to use. If you are starting a package, it may be wise to use a few to get the queen laying right away so that you get new bees as soon as possible. You can then rotate these frames out once they have drawn new comb by slowly moving them to the outside until they no longer have brood in them.
Remember if you decide not to use them and put in new foundation, you need to put 10 frames in each box at least until they draw the comb out. If you are using them for brood chambers, I would recommend leaving them with 10 frames. If you are using them for honey supers than you can reduce them to 9 frames.