Antimicrobial Ingredient in Soaps and Toothpastes Spurs Breast Cancer Cell Growth
The antimicrobial ingredient triclosan, used in soaps, toothpastes and other products, as well as the commercial substance octylphenol, promoted the growth of human breast cancer cells in lab dishes and breast cancer tumors in mice.
The findings, published in the journal Chemical Research in Toxicology, supports manufacturers' health concerns. Research by the American Chemical Society has found that two endocrine-disrupting chemicals (EDCs), triclosan and octylphenol, have accumulated in the environment.
Triclosan is an antimicrobial ingredient in many products, including soaps, cosmetics and cutting boards; and octylphenol can be found in some paints, pesticides and plastics. Triclosan, specifically, is reportedly in the urine of an estimated 75 percent of Americans.
EDCs are abundant in products, the environment and even our bodies. Researchers note that hormones play a role in the development of breast cancer, and as hormone-like compounds, EDCs are a possible link to tumor growth.
In tests on human breast cancer cells and in special immunodeficient mice with tissue grafts, the scientists found that both agents interfered with genes involved with breast cancer cell growth, resulting in more cancer cells. What's more, mice that were exposed to the two compounds had larger and denser breast cancer tumors than the control group.
"Thus, exposure to EDCs may significantly increase the risk of breast cancer development and adversely affect human health," lead researcher Kyung-Chul Choi and colleagues stated in a news release.
Product manufacturers aren't the only ones taking notice of these possibly harmful additives. The Food and Drug Administration (FDA) has revisited the issue regarding the safety of some of the most common antibacterial ingredients of household products, triclosan among them. The agency has given soap manufacturers one year to demonstrate that the substances are safe, or to take them out of the products altogether.
"It's a big deal that the FDA is taking this on," Rolf Halden, director of the Center for Environmental Security, said in a related press release.