Triclosan: Environmental Fate and Effects
Over 95% of the uses of Triclosan are in consumer products that are disposed of in residential drains. As a result, widespread use of Triclosan and other antibacterial compounds result in contamination of the nation’s waterways, with Triclosan being the most prevalent contaminant not removed by typical wastewater treatment plants. In fact, Triclosan has been detected in wastewater, activated sludge, surface water, and sediments. According to a U.S. Geological Survey study of 95 different organic wastewater contaminants in U.S. streams, Triclosan was one of the most frequently detected compounds and at some of the highest concentrations. In spring 2008, national news reports exposed the prevalence of pharmaceuticals in the nation’s watersheds, including high concentration of antibacterial compounds.
The prevalence of Triclosan in the nation’s waterways is a cause for concern since Triclosan is converted into dioxin- a highly toxic compound, when exposed the sunlight in an aqueous environment. Triclosan can also combine with chlorine in tap water to form chloroform, which is listed as a probable human carcinogen.
Triclosan has been found to be highly toxic to different types of algae, keystone organisms for complex aquatic ecosystems, and as been detected at high concentration in earthworms.
Triclosan is lipophilic and as a result is readily available for absorption and bioaccumulation in fatty tissues, especially by aquatic organisms. Studies have found that fish accumulated significant concentrations of Triclosan metabolites. Even though little is known about the effects of Triclosan on wildlife, one study found that Triclosan disrupts thyroid hormone-associated gene expression in the North American bullfrog. Other antibacterial chemicals, like triclocarban- Triclosan’s cousin, has been shown to have an amplification effect on the activity of natural hormones, which in turn can lead to adverse reproductive and developmental effects. This suggests that Triclosan and triclocarban may be endocrine disruptors.
- Pharmaceuticals and personal care products in archived U.S. biosolids from the 2001 EPA national sewage sludge survey (Water Res. 2010)
- Occurrence and loss over three years of 72 pharmaceuticals and personal care products from biosolids–soil mixtures in outdoor mesocosms (Water Res. 2010)
- Detection of the antimicrobials triclocarban and Triclosan in agricultural soils following land application of municipal biosolids (Water Res. 2009 )
- Occurrence, Fate, and Impact of Triclosan and Other Antimicrobials to Wastewater Treatment Utilities (2009)
- Fate of Triclosan & evidence for reductive dechlorination of triclocarban in estuarine sediments (Environmental Science & Technology, 2008)
- Formation of chloroform and other chlorinated byproducts by chlorination of Triclosan-containing antibacterial products (Environmental Science & Technology, 2007)
- Photolytic degradation of Triclosan in freshwater and seawater (Chemosphere, 2007)
- Monitoring the photochemical degradation of Triclosan in wastewater by UV light and sunlight using solid-phase microextraction (Chemosphere, 2006)
- Co-Occurrence of triclocarban and Triclosan in U.S. water resources (Environmental Science & Technology, 2005)
- Pharmaceuticals, hormones and other organic wastewater contaminants in U. S. streams, 1999-2000 (U.S. Geological Survey, 2002)
- Occurrence and environmental behavior of the bactericide Triclosan and its methyl derivative in surface waters and in wastewater (Environmental Science & Technology, 2002)
- Confirmation of the formation of dichlorodibenzo-p-dioxin in the photodegradation of Triclosan by photo-SPME (Analytical and Bioanalytical Chem, 2005)
- Triclosan has endocrine-disrupting effects in male western mosquitofish, Gambusia affinis. (Environ Toxicol Chem. 2010)
- Environmental Exposure of Aquatic and Terrestrial Biota to Triclosan and Triclocarban (JAWRA , 2009)
- Occurrence of Triclosan in plasma of wild Atlantic bottlenose dolphins (Tursiops truncatus) and in their environment (Environ Pollut. 2009)
- Bioaccumulation of Pharmaceuticals and Other Anthropogenic Waste Indicators in Earthworms from Agricultural Soil Amended With Biosolid or Swine Manure (Environ Sci& Tech, 2008)
- The bactericidal agent Triclosan modulates thyroid hormone-associated gene expression and disrupts postembryonic anuran development (Aquatic Tox., 2006)
- Occurrence of methyl Triclosan, a transformation product of the bactericide Triclosan, in fish from various lakes in Switzerland (Environ Sci & Tech, 2004)
- Effects of pharmaceutical & personal care products on natural freshwater algae (Environ. Sci. & Tech, 2003)
- Developmental evaluation of a potential non-steroidal estrogen: Triclosan (Marine Environ. Research, 2000)