The Ohio Department of Health is asking hospitals to stop using sexual assault evidence kits from a longtime provider because they could become contaminated with DNA from someone involved in assembling them.Hospitals have complained to the department about occasional problems with the kits, which have been assembled by Pickaway Diversified Industries in Pickaway County, which employs developmentally disabled adults. State crime lab investigators discovered the contamination when trying to track down a common and unidentified DNA profile that showed up recently inside five unrelated kits.