Philippa Darbre, who stopped using deodorants and antiperspirants eight years ago over her concerns their chemicals may cause breast cancer, has published a study that found an ingredient in some underarm cosmetics is also present in human breast cancer tumours.
Darbre’s team detected parabens, a preservative used in thousands of cosmetic, pharmaceutical and food products, in 18 of 20 breast tumours tested. Numerous studies have shown parabens can mimic the effects of estrogen, which can drive breast cancer tumour growth.
The small study, published this week in the Journal of Applied Toxicology doesn’t prove parabens cause breast cancer. But news of the controversial paper has been published in the British media and other scientists are now calling for more research to determine exactly how the parabens got into the breast tissue and whether they cause any harm.
Darbre, a senior cancer researcher at the University of Reading in the U.K., believes the answer is “blindingly simple.”
Studies have found a disproportionately high number of breast cancers in the upper, outer portion of the breast, she says. And the parabens detected in the breast cancer tumours were in a form that suggests the “route of entry” was from something put on the skin, and not eaten.
Kathleen Ljubisic, of the Canadian Cosmetic, Toiletry and Fragrance Association, says parabens “are not used particularly often” in deodorants and antiperspirants today. She believes there is no reason for people to change their underarm hygiene habits based on Darbre’s research.
Still, a study of breast cancer survivors published last year in the European Journal of Cancer Prevention found that women who used antiperspirants or deodorants and shaved frequently, and who began these habits before age 16, were diagnosed with breast cancer up to 22 years earlier than women who never, or rarely, shaved or used underarm products.
Rumours suggesting a link between deodorants and breast cancer began popping up in chain e-mail and on the internet years ago. Women were warned that a “concentration of toxins” from deodorants and antiperspirants could be absorbed through the skin, or seep into the body via razor cuts. Antiperspirants, the stories claimed, prevent women from “purging” these toxins through perspiration.