I haven't been much of a pre-washer before now except on the darker colors that usually bleed. But I think I may have developed an allergy of some kind to the finish on some of the fabrics. I can get around certain fabrics in my sewing room that have a different feeling finish to them, and I itch like crazy! So they will go into the bathtub to soak for right now, as they're precut strips from a thrift store. I've wondered if I might have gotten some mites or something in with them, but I'm the only one that itches.