Dear EarthTalk: I heard about a supposed dangerous chemical called "triclosan" that is in many personal care and other consumer products.
Triclosan is a synthetic chemical compound added to many personal and household care products to inhibit illness by preventing bacterial infection. It works by breaking down the biochemical pathways that bacteria use to keep their cell walls intact, and as such kills potentially harmful germs if used in strong enough formulations. First developed as a surgical scrub back in 1972, triclosan is now used in upwards of 700 different consumer-oriented products, many of which people use more than once a day. They include hand soaps, deodorants, toothpastes, kids' toys, yoga mats and, of course, hand sanitizers.
Whether triclosan is actually as effective as advertised, especially in the small doses found in consumer products, is a topic of much debate. Manufacturers insist that the product helps reduce infections. But researchers from the University of Michigan's School of Public Health found, after surveying 27 different studies conducted between 1980 and 2006 on the effectiveness of antibacterial soaps, that washing hands with products containing triclosan was no more effective in preventing infectious illness--and did not remove any more bacteria--than plain soaps. The analysis, "Consumer Antibacterial Soaps: Effective or Just Risky?" was published in 2007 in the peer-reviewed journal, Clinical Infectious Diseases. According to lead researcher Allison Aiello, triclosan--because of the way it reacts in living cells--may cause some bacteria exposed to it to become resistant to amoxicillin and other commonly used antibacterial drugs, but she adds that more research is needed to bear out this hypothesis.
Anti-bacterial soaps and other products utilizing triclosan may in fact be doing more harm than good for the people who use it regularly. According to the non-profit Beyond Pesticides, triclosan has been linked to various human health problems. "It is associated with skin irritation, has been shown to interfere with the body's hormones, and has been linked to an increased risk of developing respiratory illness, or asthma, and cancer, as well as subtle effects on learning ability," reports the group, adding that 75 percent of Americans are walking around today with trace levels of triclosan in their bloodstreams. Tests using lab animals have verified that exposure to large doses of triclosan can cause irreparable health damage, but industry representatives say that the levels found in consumer products are much too small to do so.
Beyond its potential human health effects, triclosan can also harm the environment. According to Beyond Pesticides, some 96 percent of the triclosan from consumer products is washed down drains where it flows into wastewater treatment plants often ill-equipped to deal with it. Inevitably some of the triclosan escapes treatment and is released into local waterways, where exposure to sunlight can convert it into dioxins, a highly toxic group of chemicals responsible for contaminating waterways and wreaking havoc on wildlife.
While the U.S. Food and Drug Administration is finally taking a fresh look at triclosan after years of controversy, consumers can do their part by asking the places they shop to stop selling products containing the controversial chemical additive. The Beyond Pesticides website offers a customizable sample letter designed to help consumers convince local retailers to forego stocking items with triclosan.
CONTACTS: Clinical Infectious Diseases, www.journals.uchicago.edu/toc/cid/current; Beyond Pesticides, www.beyondpesticides.org; U.S. Food & Drug Administration, www.fda.gov.