Studies Question Safety of Antibacterial SoapsJun 2, 2008 | Parker Waichman LLP
Researchers at the University of California, Davis have conducted three separate studies on chemicals used in germ-fighting antibacterial products and have found them to be hazardous in a variety of ways. In 2005, the Food and Drug Administration (FDA) concluded that antibacterial soaps don't prevent illness any better than ordinary soap and may be contributing to the rise of resistant bacteria.
Triclosan and triclocarban not only have the potential to affect sex hormones and interfere with the nervous system, they appear to have some links to autism. Triclosan is found in 76% of all liquid soap sold in stores and is also added to toothpaste, mouthwash, cosmetics, fabrics, and plastic kitchenware; triclocarban is a common additive in antibacterial bar soap and deodorant. Antibacterial products account for about $1 billion in sales annually.
The U.C. Davis researchers are the first to use cutting-edge molecular technology to study potential effects of triclosan and triclocarban on the human nervous system and hormones. Studies show that these chemicals are building up in the environment at an alarming rate and a recent Centers for Disease Control and Prevention (CDC) study detected triclosan in the urine of 75% of Americans aged six and older. Dan Chang, PhD, a professor of environmental engineering at U.C. Davis says, "The public should be aware of some of the concerns. These compounds should be voluntarily removed by consumer product manufacturers" and consumers should "be provided precautionary information regarding their use."
Chang, who coordinates the university's studies on triclosan and triclocarban as part of the Superfund Basic Research Program, supported by the National Institute of Environmental Health, says the U.C. Davis research indicates "there may be sensitive periods in development when these compounds could have a very subtle detrimental effect." This means that if these compounds cause harm, they are most likely to do so during pregnancy, early childhood, and adolescence. Chang argues that antibacterial soaps don't do enough good to risk this potential harm.
In one study, recently accepted for publication in the journal Environmental Health Perspectives, Isaac Pessah, PhD, director of the U.C. Davis Children's Center for Environmental Health found triclosan attached itself to special "receptor" molecules on the surface of cells raising calcium levels inside the cell; cells overloaded with calcium get overexcited. Overexcited cells may burn out neural circuits in the brain, which could lead to an imbalance affecting mental development. Because some people may carry a mutated gene that better enables triclosan to attach to cells, they could be more vulnerable to it. Because of this, Pessah named triclosan—and related compounds with similar properties—as a prime target for research into environmental factors that might cause autism.
Other researchers at U.C. Davis found triclocarban—a common additive in antibacterial bar soap and deodorant—has an unusual effect on hormones. For some time now, scientists have suspected that chemicals in the environment, known as "endocrine disruptors," may interfere with the human sex hormones and reproductive development and may cause reduced fertility in women and men, early puberty in girls, and increases in cancers of the breast, ovaries, and prostate.