Chemically a salt, and used in antiperspirants, it can be extremely irritating on abraded skin. In terms of a risk of breast cancer related to underarm deodorant, in October 2002, a study conducted at the Seattle-based Fred Hutchinson Cancer Research Center, published in the Journal of the National Cancer Institute, looked at the issue of underarm deodorant use and breast cancer. The study compared the use of underarm deodorant in 810 women who had been diagnosed with breast cancer, and 793 women who were not affected by the disease. When the two groups were compared, researchers found no evidence of an increased risk of breast cancer linked to using an antiperspirant or deodorant, or using an antiperspirant or deodorant after shaving with a traditional razor blade. In short, the researchers believed their study proved there was no link between underarm deodorants and breast cancer risk.