Triclocarban

Triclocarban, also known as TCC or 3,4,4'-trichlorocarbanilide, as a chemical with antibacterial and antifungal properties. It is often used in consumer products such as deodorant bar soaps.

In December 2013, the U.S. Food and Drug Administration (FDA) issued a proposed rule "to require manufacturers of antibacterial hand soaps and body washes to demonstrate that their products are safe for long-term daily use and more effective than plain soap and water in preventing illness and the spread of certain infections." The proposed rule explicitly references triclocarban and triclosan, because they "could pose health risks, such as bacterial resistance or hormonal effects." Specifically, the proposed rule cited concerns over animal study findings that "male rats treated with 75 and 250 mg/kg/day doses of triclocarban exhibited male sex organ toxicity, including degeneration of the seminiferous tubules, enlargement of the epididymal secretory epithelium, and a decrease or absence of sperm in epididymal ducts"; that "triclocarban enhanced the testosterone-induced androgen receptor-mediated response both in cell culture and in an in vivo rat model although triclocarban by itself had no activity"; and that "the available data are not adequate to characterize triclocarban's potential to foster the development of cross-resistance with clinically important antibiotics," citing a need for further research.

A study performed on rats found that triclocarban enhances testosterone action. There is also concern that overuse of triclocarban promotes antibiotic resistance among bacteria. With widespread use of triclocarban in personal care products, the Natural Resources Defense Council has called on the U.S. FDA to ban the chemical. In a press release, NRDC Senior Scientist Dr. Sarah Janssen said, "With no proven benefit and many red flags raised for harmful health impacts, the use of these so-called anti-microbials is an unnecessary and stupid use of toxic chemicals." On July 27, 2010, NRDC filed a lawsuit against the FDA for its failure to finalize a ban on oth triclocarban and triclosan, which was first initiated in 1978. The lawsuit covers liquid and bar soaps and body washes. With its common household use, triclocarban makes its way into the wastewater stream and frequently turns up in sewage sludge.

Uses
Triclocarban is primarily used in deodorant bar soaps. Brands and products containing triclocarban include bar soaps from the following brands: Coast, Dial, Irish Spring, Safeguard, and Zest. However, a study comparing the health effects of handwashing with antibacterial soap containing triclocarban and regular soap found no difference in the effectiveness at preventing infections between the two types of soap.

Human Exposure and Health Effects
As of 2010, the Centers for Disease Control does not monitor for human exposure to triclocarban. However, triclocarban is present in the environment (see below) and research has shown that it is rapidly absorbed across the skin and can be measured in serum within minutes of topical application.

Endocrine Disruption
Triclocarban is an endocrine disruptor that is described by scientists as unique in its modes of action. Triclocarban shows no endocrine activity by itself and instead seems to enhance the gene expression of other steroid hormones, including androgens, estrogens, and cortisol. In rats, dietary exposure to 0.25% triclocarban for 10 days was found to increase male accessory sex organ weights (seminal vesicles, prostate and levator ani) in intact male rats and uterine weight in females without notable histopathology.

Triclocarban as a Pollutant
Triclocarban is a highly persistent chemical in the environment and it does not degarde for over a decade. Wastewater treatment plants releasing effluent and sewage sludge into the environment are the major source of environmental contamination of triclocarban. Research published in 2007 found triclocarban in 100% of river water samples collected downstream of wastewater treatment plants, as compared to 56% of those taken upstream. Concentrations of triclocarban in samples taken downstream of wastewater treatment plants were significantly higher than those of samples taken upstream. In another study, the same group of researchers concluded that approximately three-quarters of the triclocarban mass disposed of by consumers ultimately is released into the environment by application of sewage sludge on agricultural land as fertilizer. Together, triclocarban and triclosan are the most abundant contaminants in surveys of sewage sludge where together they account for nearly two-thirds of the pharmaceuticals and personal care products mass.

Plant Uptake of Triclocarban
A study by researchers at the University of Toledo examined the uptake of three pharmaceuticals, carbamazepine, diphenhydramine (Benadryl), and fluoxetine (Prozac), and two personal care products, triclosan and triclocarban, by soybean plants. The plants were grown in "treatments simulating biosolids application and wastewater irrigation." The plants were then examined after growing for 60 and 110 days. The plants concentrated carbamazepine, triclosan, and triclocarban in their roots but the three chemicals were found translocated in the above ground parts of the plants, including the beans. Concentrations were higher in the plants grown in simulated biosolids, or sewage sludge.

Related SourceWatch Articles

 * Triclosan
 * Biosolids
 * Sewage sludge
 * Food Rights Network

External Resources

 * Natural Resources Defense Council, "Not Effective and Not Safe: The FDA Must Regulate Dangerous Antimicrobials in Everyday Products Facts," April 2010

External Articles

 * Jill Richardson, "Two Dangerous Ingredients in Everyday Products That Are Threatening Our Health", AlterNet, August 20, 2010.