Mrs. Dinah, I can't answer your question BUT I have access to plastic 55 gallon drums throught my grandfathers brick business. they come with detergent in them for rinsing brick after they have been layed and I have never done anything more than washed em out with bleach and water. I've never had a problem with using them for dog houses and I have been for a few years now. Let me know how many ya'll need, I can hook you up!
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