A quick wipe-down or even a hosing will not hurt wood that is in good condition. It’s the long term effects of molds, mildews and, possibly, compression set that can cause problems. One other consideration is that the doors may have paint on them that contains lead. Removing this so you don’t have rubbing or scraping of the lead based paint into the area is important. The best way to accomplish this, either for paint or for a clear film finish (like varnish) removal is with a good stripper. I would suggest that Peel Away 1 would be a good choice for you to consider. Check this out at their web site http://www.peelaway.com or at a Sherwin-Williams store or other stocking location.
Henry in MI