bioaccumulation gone bad
Anti-bacterial soap isn't as useful as you'd hoped, UT student org drawsattention to the issue
Recently, the University of Texas student government assembly unanimously passed a resolution calling for a ban on anti-bacterial soaps on campus. After some investigation, it turns out the University doesn’t use such soap. Instead, the University of Texas follows a program known as OS1 in the professional custodial industry, which uses hospital-grade cleaning products, not anti-bacterial soaps.
Even though the campus ended up being anti-bacterial-free, the students caught on to what could have been a problem. For one thing, anti-bacterial soaps don’t provide any real benefit. The U.S. Food and Drug Administration found no evidence that triclosan, the active ingredient in antibacterial soaps and body washes, “provides any benefit over washing with regular soap and water” or that it offers any extra health benefit in other consumer products (although triclosan in toothpaste does seem to help prevent gingivitis).
There are also concerns about possible negative side effects. Triclosan is a potential endocrine disruptor, for example, and it may contribute to the growing problem of antibiotic-resistant bacteria. In light of questions raised by recent animal studies of triclosan, the FDA is reviewing all of the available evidence on the safety of this ingredient in consumer products.
A 2009 study by the U.S. Centers for Disease Control and Prevention found that 75 percent of Americans older than 5 have triclosan in their urine. Triclosan is prevalent in soaps, cosmetics, deodorants, fabrics and a host of other consumer products.
Another serious concern is what happens when this chemical washes down the drain and, eventually, into the ocean. Consumer products that ultimately swirl down residential drains account for more than 95 percent of the uses of triclosan. Wastewater treatment plants don’t remove triclosan from the water, and the compound is highly stable for long periods of time, meaning that significant amounts end up in our waterways.
In fact, the chemical was found to be widespread in U.S. waterways as early as 2005, and in a U.S. Geological Survey study of 95 organic wastewater contaminants in U.S. streams, triclosan was one of the most frequently detected, and in some of the highest concentrations. Triclosan has been found to be highly toxic to different types of algae, affecting both the structure and function of algal communities in stream ecosystems, with the potential to destroy the balance of aquatic ecosystems.
As triclosan is lipophilic (thus, resistant to degradation), it's readily available for the absorption and bioaccumulation of organisms in the aquatic environment. Last year, the University of California - Davis researchers found that triclocarban, a related ingredient, builds up in fish.
"The fish quickly accumulated TCC," Flores said. "The levels of the TCC in the fish soon after exposure were about 1,000 times higher than the concentration in the water. To the best of our knowledge, this is the first report of uptake and metabolism of TCC in fish species."
Lastly, scientists at the University of Minnesota found that, when in the water supply, triclosan can be converted to dioxins by sunlight, making it a potential source of highly toxic dioxins in the environment. The researchers stated that even low levels of very toxic dioxin are troublesome because the chemical readily accumulates in organisms, becoming more concentrated in the organisms' tissues as it moves up the food chain.
Given these concerns and the lack of any real benefit, perhaps we take a cue from the students and enact our own personal ban on anti-bacterial soaps.