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Triclosan is another bisphenol compound that has seen widespread application in antibacterial products over the last several decades. Initially used in toothpastes, triclosan is now commonly used in hand soaps and is frequently impregnated into a wide variety of other products, including cutting boards, knives, shower curtains, clothing, and concrete, to make them antimicrobial. It is particularly effective against gram-positive bacteria on the skin, as well as certain gram-negative bacteria and yeasts. US Food and Drug Administration. “Triclosan: What Consumers Should Know.” 2015. http://www.fda.gov/ForConsumers/ConsumerUpdates/ucm205999.htm. Accessed June 9, 2016.

Triclosan: antibacterial overkill?

Hand soaps and other cleaning products are often marketed as “antibacterial,” suggesting that they provide a level of cleanliness superior to that of conventional soaps and cleansers. But are the antibacterial ingredients in these products really safe and effective?

About 75% of antibacterial liquid hand soaps and 30% of bar soaps contain the chemical triclosan, a phenolic, ( [link] ). J. Stromberg. “Five Reasons Why You Should Probably Stop Using Antibacterial Soap.” Smithsonian.com January 3, 2014. http://www.smithsonianmag.com/science-nature/five-reasons-why-you-should-probably-stop-using-antibacterial-soap-180948078/?no-ist. Accessed June 9, 2016. Triclosan blocks an enzyme in the bacterial fatty acid-biosynthesis pathway that is not found in the comparable human pathway. Although the use of triclosan in the home increased dramatically during the 1990s, more than 40 years of research by the FDA have turned up no conclusive evidence that washing with triclosan-containing products provides increased health benefits compared with washing with traditional soap. Although some studies indicate that fewer bacteria may remain on a person’s hands after washing with triclosan-based soap, compared with traditional soap, no evidence points to any reduction in the transmission of bacteria that cause respiratory and gastrointestinal illness. In short, soaps with triclosan may remove or kill a few more germs but not enough to reduce the spread of disease.

Perhaps more disturbing, some clear risks associated with triclosan-based soaps have come to light. The widespread use of triclosan has led to an increase in triclosan-resistant bacterial strains, including those of clinical importance, such as Salmonella enterica ; this resistance may render triclosan useless as an antibacterial in the long run. SP Yazdankhah et al. “Triclosan and Antimicrobial Resistance in Bacteria: An Overview.” Microbial Drug Resistance 12 no. 2 (2006):83–90. L. Birošová, M. Mikulášová. “Development of Triclosan and Antibiotic Resistance in Salmonella enterica serovar Typhimurium.” Journal of Medical Microbiology 58 no. 4 (2009):436–441. Bacteria can easily gain resistance to triclosan through a change to a single gene encoding the targeted enzyme in the bacterial fatty acid-synthesis pathway. Other disinfectants with a less specific mode of action are much less prone to engendering resistance because it would take much more than a single genetic change.

Use of triclosan over the last several decades has also led to a buildup of the chemical in the environment. Triclosan in hand soap is directly introduced into wastewater and sewage systems as a result of the handwashing process. There, its antibacterial properties can inhibit or kill bacteria responsible for the decomposition of sewage, causing septic systems to clog and back up. Eventually, triclosan in wastewater finds its way into surface waters, streams, lakes, sediments, and soils, disrupting natural populations of bacteria that carry out important environmental functions, such as inhibiting algae. Triclosan also finds its way into the bodies of amphibians and fish, where it can act as an endocrine disruptor. Detectable levels of triclosan have also been found in various human bodily fluids, including breast milk, plasma, and urine. AB Dann, A. Hontela. “Triclosan: Environmental Exposure, Toxicity and Mechanisms of Action.” Journal of Applied Toxicology 31 no. 4 (2011):285–311. In fact, a study conducted by the CDC found detectable levels of triclosan in the urine of 75% of 2,517 people tested in 2003–2004. US Centers for Disease Control and Prevention. “Triclosan Fact Sheet.” 2013. http://www.cdc.gov/biomonitoring/Triclosan_FactSheet.html. Accessed June 9, 2016. This finding is even more troubling given the evidence that triclosan may affect immune function in humans. EM Clayton et al. “The Impact of Bisphenol A and Triclosan on Immune Parameters in the US Population, NHANES 2003-2006.” Environmental Health Perspectives 119 no. 3 (2011):390.

In December 2013, the FDA gave soap manufacturers until 2016 to prove that antibacterial soaps provide a significant benefit over traditional soaps; if unable to do so, manufacturers will be forced to remove these products from the market.

A chemical structure of triclosan. Two carbon rings (6 carbons) connected by an oxygen; each ring has 2 more oxygens bound to it. A photo of someone washing their hands.
Triclosan is a common ingredient in antibacterial soaps despite evidence that it poses environmental and health risks and offers no significant health benefit compared to conventional soaps. (credit b, c: modification of work by FDA)

Questions & Answers

what is fermentation example ?
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is proceess in which an agent couses of an oganic substances breakdown into simpler substance,especially in aneorobic breakdown of suger into alcohol.
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at the tip of variable region on the antibody...where antigen and antibody binding sites combine...
The term that is used refer to moving microbes under a microscope are referred to as?
Lee Reply
Members of the genus Neisseria cause which of the folowing human diseases?
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genital infections
4. Which of the following specimens should not be refrigerated? a. Urine b. Urogenital swab
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Details about McConkey agar
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a member of large number of unicellular microorganism which have cell wall but lack of cell organelles an oranised nucleus including somewhat can cause disease
Bacteria are usually composed of one cell onl to that are neither plants nor animals, microscopic, that may cause diseases or may be beneficial(in gut)... it depends upon their weapons. Nearly all animal life is dependent on Bacteria for their survival
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nutrient concentration temp gaseous conc ph ion or salt concentration mositure condition factors contribute to make large colony. by autoclaving we will sterilize bactetia
Colony is actually visible growth of Bacteria that is as a result of suitable environment for growth i.e optimal conditions for growth, temperature, moisture etc. there're many methods to get rid of bacteria. If We stop giving them optimal conditions for living Bacteria will die soon .
what's the difference between an antigen and a pathogen?
Pathogens are organisms that cause disease in other organisms whereas Antigen is a part of a pathogen that triggers the immune response..
so it is the antigen that dendritic cells present to the T cells and not the pathogen itself?
no no antigen are the west product or part of the pathogen. in such case bacteria it self fight with over immune response & in another case bacteria release antigens
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pathogen are microbes that can infect the body and causw illness....antigens are the part of pathogens that alert the body to an infection
antigen is a part of blood and pathogen is foreign particle which causes diseases
antigen could be non microorganism.... where as pathogen is mixroorganism
a pathogen is a disease causing organism while an antigen is a protein in the white blood cells which combats pathogens.
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this test determine for typhoid in this test if H,O antigen are present that indicate the positive test bac. are salmonella typhy
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o: body of bacteria, h: flagellate
Explain Mould
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The antibody binding site is formed primarily by:
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How many types of MICROORGANISMS do we have?
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Hello friends
microorganisms are divided into seven type Bacteria archaea protozoa algae fungi virus and multicellular animal parasites

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