There is no proof that the use of antiperspirants or deodorants causes breast cancer, contrary to widespread rumor, according to a new study reported in the Journal of the National Cancer Institute (Vol. 94, No. 20: 1578-1580).

This rumor had circulated widely on the Internet, and it became a public concern. It was a kind of urban myth despite the fact there had not been any published scientific reports proving a risk.

Dana K. Mirick, MS, and colleagues at the Fred Hutchinson Cancer Research Center in Seattle, conducted a study on 813 women in western Washington ages 20 to 74. These women were first diagnosed with breast cancer from 1992 to 1995, and then were compared to 793 women without the disease.

They found no link between breast cancer and antiperspirants or deodorants.

The authors addressed whether these cosmetics were used regularly within one hour of shaving. "Specifically there was concern that such products might contain harmful substances that could be absorbed via small nicks or abrasions caused by hair removal," they wrote. Particular analysis of razor blade shaving was also done.

Whether the women used antiperspirants or deodorants, or shaved with a blade razor or used another form of underarm hair removal, there was no evidence of a link to the risk of breast cancer, concluded the authors.

The authors hope that the findings in their study will "help alleviate the concern of many that use of underarm antiperspirants or deodorants could alter their risk for breast cancer."