I lucked out at an estate sale and purchased a large amount of fabric - mainly to use as backing. Some pieces are 10 yards long...but...had a heavy cigarette odor. They are now washed and folded, but, I don't know my next step. I normally do not prewash my fabric and wonder if I will have to prewash it for the quilt tops. Even the teeny 2 inch squares I have already cut for scrappy quilts? Would it make a big difference if I did not prewash and just heavily starched the backing? Help!