Triclosan is an anti-bacterial ingredient in many cosmetics and personal-care products. These include nearly half of all commercial antibacterial liquid soaps, cleansers, deodorants, detergents, toothpastes, and mouthwashes.
Water testing studies by the U.S. Geological Survey have found that triclosan is among the top 10 persistent contaminants in U.S. rivers, streams, lakes, and underground aquifers. Of related concern, triclosan persists in the environment, accumulating as it passes up the food chain to our bodies, and contributes to reduced resistance to antibiotics.
Unexpected volatility has been documented when the triclosan in liquid soaps and other household products comes into contact with water, as would happen during common use. At Virginia Tech University, a team of researchers in April 2005 reported that some toothpastes and soaps create a chloroform gas when the triclosan in these products reacts with chlorinated tap water. Triclosan also interacts with free chlorine in tap water and degrades under sunlight to produce chloroform, which is both toxic and carcinogenic following inhalation or skin absorption, particularly while bathing in warm water.
Triclosan, has been shown to produce toxic hormonal effects, known as endocrine disruption, on the development of the thyroid gland in tadpoles, and on sex ratios and fin length in fish. Lab studies on rats have shown that triclosan is toxic to normal liver enzymes. In humans, this preservative has been linked to allergies, asthma, and eczema.
Of further concern, triclosan has been identified as a contaminant in umbilical cord samples collected by Greenpeace International and Britain's World Wifeline Fund. Furthermore, surveys in Sweden have also identified triclosan in the breast milk of 60 percent of women tested.
Based on these concerns, a 2005 advisory panel to the FDA concluded that triclosan posed "unacceptable health and environmental risks." However, the FDA still ignores this warning.