Triclosan

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Triclosan
Triclosan.svg
Triclosan-3D-vdW.png
Identifiers
CAS number 3380-34-5 YesY
PubChem 5564
ChemSpider 5363 YesY
UNII 4NM5039Y5X YesY
DrugBank DB08604
KEGG D06226 YesY
ChEBI CHEBI:164200 YesY
ChEMBL CHEMBL849 YesY
ATC code D08AE04,
D09AA06 (medicated dressing)
Jmol-3D images Image 1
Properties
Molecular formula C12H7Cl3O2
Molar mass 289.54 g mol−1
Appearance White solid
Density 1.49 g/cm3
Melting point 55-57 °C
Boiling point 120 °C (248 °F; 393 K)
Hazards
MSDS MSDS
NFPA 704
Flammability code 1: Must be pre-heated before ignition can occur. Flash point over 93 °C (200 °F). E.g., canola oil Health code 2: Intense or continued but not chronic exposure could cause temporary incapacitation or possible residual injury. E.g., chloroform Reactivity code 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g., liquid nitrogen Special hazards (white): no codeNFPA 704 four-colored diamond
Flash point 162.2 °C (324.0 °F; 435.3 K)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
 YesY (verify) (what is: YesY/N?)
Infobox references

Triclosan is an antibacterial and antifungal agent found in numerous consumer products. It is a polychloro phenoxy phenol.

According to the United States' Food and Drug Administration (FDA), at the present time, there is no evidence that triclosan in personal care products provides extra benefits to health beyond its anti-gingivitis effect in toothpaste.[1] The FDA does not recommend changing consumer use of triclosan-containing products one way or the other due to insufficient safety evidence.[1] Studies by the Environmental Protection Agency (EPA) found triclosan to be an effective antibacterial.[2] Triclosan safety is currently under review by the FDA[1] and Health Canada.[3] A systematic review of randomized controlled trials found that triclosan-containing toothpastes are marginally beneficial in reduction of tooth cavities and reduces dental plaque, gingival inflammation, and gingival bleeding.[4]

Chemical structure and properties[edit]

This organic compound is a white powdered solid with a slight aromatic/phenolic odor. It is a chlorinated aromatic compound that has functional groups representative of both ethers and phenols. Phenols often show antibacterial properties. Triclosan is only slightly soluble in water, but soluble in ethanol, methanol, diethyl ether, and strongly basic solutions such as a 1 M sodium hydroxide solution. Triclosan can be synthesized from 2,4-dichlorophenol.

Some common impurities are: 2,4-dichlorophenol, 3-chlorophenol, 4-chlorophenol, 2,3,7,8-tetrachlorodibenzo-p-dioxin, 2,3,7,8-tetrachlorodibenzo-p-furan, 2,8-dichlorobenzo-furan, 2,8-dichlorobenzo-p-dioxin, 1,3,7-trichlorodibenzo-p-dioxin and 2,4,8-trichlorodibenzo-furan.[5]

Synthesis[edit]

2,4,4'-trichloro-2'-methoxydiphenyl ether is treated with aluminium chloride in benzene under reflux.[citation needed]

Triclosan can be synthesized through a three-step process starting with 1-(2-hydroxyethyl)pyrrolidin-2-one. The 1-(2-hydroxyethyl)pyrrolidin-2-one is to be dehydrated with either zinc or calcium oxide into 1-vinylpyrrolidin-2-one.[6] Then, 1-vinylpyrrolidin-2-one can be reacted with 5-chloro-2-(2,4-dichlorophenoxy)phenyl acrylate in n-heptane to form triclosan.[7]

Reactions[edit]

It can be used to produce 2-(2,4-dichloro-phenoxy)-4,5-dichloro-phenol at 20 °C with the reagent sulfuryl chloride.[citation needed]

Uses[edit]

Triclosan has been used since 1972, and it is present in soaps (0.10-1.00%), shampoos, deodorants, toothpastes, mouth washes, and cleaning supplies,[8] and is incorporated into an increasing number of consumer products, such as kitchen utensils, toys, bedding, socks, and trash bags.[9][10] It is also found in health care settings in surgical scrubs and personnel hand washes.[11] Triclosan has been shown to be effective in reducing and controlling bacterial contamination on the hands and on treated products. More recently, showering or bathing with 2% triclosan has become a recommended regimen in surgical units for the decolonization of patients whose skin is carrying methicillin-resistant Staphylococcus aureus (MRSA)[12] following the successful control of MRSA outbreaks in several clinical settings. Use in surgical units is effective with a minimum contact time of approximately 2 minutes.[13][14]

Antimicrobial hand soaps including those containing triclosan have been shown in studies to provide a slightly greater bacterial reduction on the hands compared to plain soap.[15] In addition, researchers at Dial found that the transfer of bacteria to objects was reduced following washing with antimicrobial hand soap containing triclosan compared to plain soap.[16] The FDA's current stance on triclosan differs, based on their analysis of the body of research, and is as follows: "At this time, FDA does not have evidence that triclosan added to antibacterial soaps and body washes provides extra health benefits over soap and water. Consumers concerned about using hand and body soaps with triclosan should wash with regular soap and water." [17]

Triclosan is regulated by the U.S. Food and Drug Administration, the Environmental Protection Agency, and the European Union. During wastewater treatment, a portion of triclosan is degraded, while the remaining adsorbs to sewage sludge or exits the plant in wastewater effluent.[18][19] In the environment, triclosan may be degraded by microorganisms or react with sunlight, forming other compounds, which include between 3 and 12% of chlorophenols and dioxin (In particular, 2,8-dichlorodibenzo-p-dioxin[20] (2,8-DCDD) and 2,4-dichlorophenol (2,4-DCP) are produced. Both also are photolabile and, thus, are intermediates.), or it may adsorb to particles that settle out of the water column and form sediment.[18][21] Triclosan has been found in Greifensee sediment that was over 30 years old, suggesting that triclosan is degraded or removed slowly in sediment.[18]

The use of triclosan as an additive for plastic production for use in food packages has not been approved by the European Commission (EC).[22] Triclosan is used in a variety of common household products, including soaps, mouthwashes, dish detergents, toothpastes, deodorants, and hand sanitizers.[23] In the United States, manufacturers of products containing triclosan must indicate it on the label. The ingredient is regulated as a cosmetic preservative within Europe and in accordance with the European Cosmetic Regulation all cosmetic ingredients have to be listed on the label.[24]

Triclosan also has been employed as an effective selective agent in molecular cloning. Bacteria host transformed by plasmids harboring a triclosan resistant mutant FabI gene (mFabI) as a selectable marker can grow in presence of high dose of triclosan in the culture media.[25]

Mechanism of action[edit]

At in-use concentrations, triclosan acts as a biocide, with multiple cytoplasmic and membrane targets.[26] At lower concentrations, however, triclosan appears bacteriostatic and is seen to target bacteria mainly by inhibiting fatty acid synthesis. Triclosan binds to bacterial enoyl-acyl carrier protein reductase enzyme (ENR), which is encoded by the gene FabI. This binding increases the enzyme's affinity for nicotinamide adenine dinucleotide (NAD+). This results in the formation of a stable ternary complex of ENR-NAD+-triclosan, which is unable to participate in fatty acid synthesis. Fatty acids are necessary for reproducing and building cell membranes. Humans do not have an ENR enzyme, and thus are not affected. Some bacterial species can develop low-level resistance to triclosan at its lower bacteriostatic concentrations because of FabI mutations, which results in a decrease of triclosan's effect on ENR-NAD+ binding, as shown in Escherichia coli and Staphylococcus aureus.[27][28] Another way for these bacteria to gain low-level resistance to triclosan is to overexpress FabI.[29] Some bacteria have innate resistance to triclosan at low, bacteriostatic levels, such as Pseudomonas aeruginosa, which possesses multi-drug efflux pumps that "pump" triclosan out of the cell.[30] Other bacteria, such as some of the Bacillus genus, have alternative FabI genes (FabK) to which triclosan does not bind and hence are less susceptible.

Environmental concerns[edit]

Treatment and disposal of triclosan[edit]

The duration of triclosan in personal product use is relatively short. Upon disposal, triclosan is washed down the drain to municipal wastewater treatment plants, where about 97-98% of triclosan is removed from the water.[citation needed] Studies show that substantial quantities of triclosan (170,000 – 970,000 kg/yr) can break through wastewater treatment plants and damage algae on surface waters.[citation needed] Discharge of effluent from these treatment plants and disposal of sludge on land is the primary route of environmental exposure to triclosan.[citation needed] Research shows that triclosan has been detected in sewage effluents and sludge (biosolids) due to its incomplete removal during wastewater treatment.[31] Because of their hydrophobic nature, significant amounts of them in wastewater streams partition into sludge, with concentrations at mg/kg levels. The volume of triclosan reentering the environment in sewage sludge after initial successful capture from wastewater is 44,000 ± 60,000 kg/yr.[32]

The use of triclosan in household antibacterial products introduces triclosan to surface waters where it can degrade to a non-toxic[33] type of dioxin. The dioxin-like compound that formed when triclosan degraded in sunlight and wastewater chlorine treatment were analyzed in sediment cores by University of Minnesota researchers.[34] The US EPA and World Health Organization has recognized that dioxins formed from triclosan are not considered to be those congeners of toxicologic concern for mammals, birds, and fish.[35][36]

Incomplete removal of triclosan during wastewater treatment results in effluent and biosolids with trace amounts of triclosan. This poses a potential environmental and ecological hazard, particularly for aquatic systems. In a study on effluent from wastewater treatment facilities, approximately 75% of triclocarban was present in sludge.[37] Triclosan can attach to other substances suspended in aquatic environments, which potentially endangers marine organisms and may lead to further bioaccumulation.[38] Ozone is considered to be a a tool for removing triclosan during sewage treatment. Because little triclosan is released through plastic and textile household consumer products, these are not considered to be major sources of triclosan contamination.[39]

Bioaccumulation[edit]

While studies using semi-permeable membrane devices have found that triclosan does not strongly bioaccumulate, methyl-triclosan is comparatively more stable and lipophilic and thus poses a higher risk of bioaccumulation in organisms. The ability of triclosan to bioaccumulate is affected by its ionization state in different environmental conditions. At higher pHs, triclosan is expected to bioaccumulate more. At a lower pH, methyl-triclosan is much more likely to bioaccumulate.[40] Analysis of human autopsies have shown that triclosan can bioaccumulate in the liver and adipose tissues, but not in brain tissues.[41]

Ecotoxicity[edit]

Triclosan and triclocarban (TCC) could have adverse repercussions on agriculture. Studies have indicated that TCC and TCS are absorbed through shoot systems in vegetables, at higher levels in roots than in tubers. While the levels of TCC and TCS in the vegetables are largely insufficient to cause major health damage, the levels of these chemicals is higher than in the drinking water supply.[42] Crops shown to take up antimicrobials from soil include barley, meadow fescue, carrots and pinto beans. Triclosan may also affect animal wildlife behavior.[43] For example, TCS and TCC are 100-1,000 times more effective in inhibiting and killing algae, crustaceans and fish than they are in killing microbes. TCS have been observed in multiple organisms, including algae aquatic blackworms, fish and dolphins. Earth dwelling species include earth worms, and higher species up the food chain[44]

Resistance concerns[edit]

An article coauthored by Stuart Levy in the August 6, 1998 issue of Nature[45] warned that triclosan's overuse could cause resistant strains of bacteria to develop, in much the same way that antibiotic-resistant bacterial strains are emerging. In 2003, the Scottish Sunday Herald newspaper reported that some UK supermarkets and other retailers were considering phasing out products containing triclosan.[46]

It has since been shown that while the laboratory method used by Levy was not effective in predicting bacterial resistance for biocides like triclosan, triclosan does reduce species diversity, kills off efficient TCS degrader species (see citation's Table 4), and that it should be considered that "degradation of an ecosystem may rearrange the competitive hierarchy".[47] At least seven peer-reviewed and published studies have been conducted demonstrating that triclosan is not significantly associated with bacterial resistance over the short term, including one study coauthored by Levy.[48] However, the major concern over resistant strains is not that they will alter resistance profiles over the short term. The concern is that superbugs will evolve against which no bactericide can be used. For example, as noted above, triclosan is effective against MRSA.

Some level of triclosan resistance can occur in some microorganisms, but the larger concern is with the potential for cross-resistance or co-resistance to other antimicrobials. Studies investigating this possibility have been limited.[49] The European Commission Scientific Committee on Consumer Safety (SCCS) concludes that to date, there is no evidence that using triclosan leads to an increase in antibiotic resistance. However it is too early to say that triclosan exposure never leads to microbial resistance, as there is not yet enough information to make a full risk analysis.[50]

Health concerns[edit]

Triclosan is a chlorinated aromatic compound with antibacterial, antifungal and antiviral properties (sold under several trade names, including UltraFresh, Amicor, and BioFresh). Triclosan is also a component in some pesticides, mattresses, insulation, and underlayments that install under various types of flooring, including laminate, wood, glued down, and engineered wood, and carpeting for the purpose of slowing or stopping the growth of bacteria, fungi, and mildew. For example, some high density sound-suppressing underlayments, foam floor underlayments and rebond carpet pads are treated with triclosan. Triclosan penetrates the skin on contact and enters the bloodstream.[51] The EPA concluded that total exposure to triclosan did not present risks of concern for human health, including allergy, cancer, reproductive, endocrine and neurotoxic effects.[52]

Allergy[edit]

A 2010 study found that children who had higher exposure to triclosan had a higher incidence of hay fever.[53] Triclosan has also been associated with a higher risk of food allergy.[54] This may be because exposure to bacteria reduces allergies, as predicted by the hygiene hypothesis and not toxicology of the triclosan itself. This would also occur with chlorhexidine gluconate and PCMX, among other antibacterial agents.[53][55] Other studies have linked triclosan to allergic contact dermatitis in some individuals.[56][57] The EPA concluded in its 2008 report that triclosan does not present allergy risks.[52]

By-products[edit]

In August 2009, the Canadian Medical Association asked the Canadian government to ban triclosan use in household products under concerns of creating bacterial resistance and producing dangerous side products (chloroform).[58]

Triclosan can also react with the free chlorine in tap water to produce lesser amounts of other compounds, like 2,4-dichlorophenol.[59] Most of these intermediates convert into dioxins upon exposure to UV radiation (from the sun or other sources). Although small amounts of dioxins are produced, some dioxins are extremely toxic and are very potent endocrine disruptors. They are also chemically stable, so that they are eliminated from the body slowly (they can bioaccumulate to dangerous levels), and they persist in the environment for a long time.[60] The dioxins which can be formed from triclosan are not considered to be those congeners of toxicologic concern for mammals, birds, and fish[35][36]

The United States Pharmacopeia has established a monograph for triclosan that sets purity standards (>97%).[61]

The American Dental Association published a response to the concerns stemming from the Virginia Tech study stating that the study is not relevant to toothpaste.[59][62]

Environment[edit]

Triclosan is toxic to aquatic bacteria at levels found in the environment. Triclosan inhibits photosynthesis in diatom algae which are responsible for a large part of the photosynthesis on Earth.[63]

Endocrine disruption[edit]

Triclosan has been associated with lower levels of thyroid hormone and testosterone. Specifically, triclosan decreases circulating levels of thyroxine hormone (T4) by increasing glucuronidase enzyme activity, which catabolizes T4 and other thyroid hormones.[64]This may lead to altered behavior, learning disabilities, and/or infertility. Very low doses of triclosan have been shown to act as an estrogen mimic and increase proliferation rates of breast cancer tumors.[65] It may also chemically mimic thyroid hormone and bind to the hormone receptor sites, blocking them, so that normal hormones cannot be used. A study between 2003 and 2006 concluded that triclosan (as an endocrine disruptor) affects the immune system and showed a positive association with allergy or hay fever diagnosis.[66] Another study in 2000 offered the result that low amount of triclosan can be absorbed through skin and can enter the bloodstream.[67]

Triclosan has also been found in both the bile of fish living downstream from waste-water-processing plants and in human milk.[68] The negative effects of triclosan on the environment and its questionable benefits in toothpastes[69] have led to the Swedish Naturskyddsföreningen to recommend not using triclosan in toothpaste.[70] Another 2009 study demonstrated that triclosan exposure significantly impacts thyroid hormone concentrations in the male juvenile rats.[71] However, a 4-year study of possible effects of triclosan (0.3%) in toothpaste on thyroid hormone function found no effect of triclosan on thyroid hormone concentration in sera of adult human subjects. [72]

Muscle contraction[edit]

Triclosan has been reported to impair excitation-contraction coupling in cardiac and skeletal muscle function in mice.[73]

Breakdown of triclosan[edit]

TCS is structurally related to highly toxic and carcinogenic dioxins. In 1993, it was labeled by the EPA as a pre-dioxin, and TCS contains traces of the most toxic member of the dioxin family, 2,3,7,8-tetrachlorodibenzo-p-dioxin. The rising concern of TCS toxicity has pushed producers of antimicrobial products to acquire TCS from European chemical supplies because the production is very tightly regulated. TCS can mix with chlorinated drinking to form carcinogenic chloroform and, upon release into surface water and irradiation with sunlight, release additional toxic intermediates.[74] These intermediates can be cleaved to form chlorophenols that can react with free chlorine to form trihalomethanes, such as chloroform.[75] As a result, triclosan was the target of a UK cancer alert, even though the study showed that the amount of chloroform generated was less than amounts often present in chlorinated drinking water.

Alternatives[edit]

A comprehensive analysis from the University of Michigan School of Public Health indicated that plain soaps are just as effective as consumer-grade antibacterial soaps with triclosan in preventing illness and removing bacteria from the hands.[76]

Nonorganic antibiotics and organic biocides are effective alternatives to triclosan, such as silver and copper ions and nanoparticles.[77]

Policy[edit]

In light of the difficulties of finding antimicrobial alternatives, the Food and Drug Administration began in the 1970s to review the safety of triclocarban and triclosan, but no enacted policy, or "drug monograph" is available to date.[78] Legal recourse by the Natural Resources Defense Council in 2010 forced the FDA to review triclosan.[79] However, the United States Environmental Protection Agency maintains regulatory control over triclosan to date.[80]

Similar in its use and its adverse health impacts as triclosan, hexachlorophene became prohibited by the FDA.[81]

Current and future research[edit]

The future of TCC is unknown, but scientists are searching for more sustainable antimicrobials that maintain its antibacterial properties while being minimally toxic to the envrionment, humans, and wildlife. This entails low degrees of bioaccumulation and rapid, clean biodegredation in existing wastewater treatment facilities.A lowered potential or no potential for resistance is also preferable.[82] These next generation chemicals should aim to act on a broad spectrum of microbes and pathogens while also being minimally toxic and bioaccumulating in non-target species.

Synthesis of these compounds could be improved upon by finding renewable sources for their production that lacks occupational hazards.[83] Research regarding the sustainability of chemical production is currently being used to help formulate green pharmaceuticals. These same principles may be applied to the development of improved antimicrobials.[84] Development in this area would benefit both people and the environment.[85]

See also[edit]

References[edit]

  1. ^ a b c "Triclosan: What Consumers Should Know". U S Food and Drug Administration. 8 April 2010. Retrieved 13 April 2010. 
  2. ^ http://www.epa.gov/oppsrrd1/REDs/factsheets/triclosan_fs.htm[full citation needed]
  3. ^ "Toxic chemical monitoring program gets $500M". CBC. 4 October 2011. 
  4. ^ Philip Riley and Thomas Lamont. (December 2013). "Triclosan/copolymer containing toothpastes for oral health". Cochrane Database of Systematic Reviews 12 (CD010514). doi:10.1002/14651858.CD010514.pub2. PMID 24310847. 
  5. ^ Triclosan and its impurities - Quantex Labs www.quantexlabs.com/Portals/159220/docs/triclosan-impurities.pdf
  6. ^ Kahn, A.P. Production of N-Vinyl Pyrrolidone. US Patent 63970, Apr 1, 2004.
  7. ^ Plochocka, K. Polymeric Delivery and Release Systems for Oral Care Actives. US Patent 6,315,987, Nov 13, 2001.
  8. ^ Thompson A, Griffin P, Stuetz R, Cartmell E (2005). "The fate and removal of triclosan during wastewater treatment". Water Environ. Res. 77 (1): 63–7. doi:10.2175/106143005X41636. JSTOR 25045839. PMID 15765937. 
  9. ^ Record in the Household Products Database of NLM
  10. ^ Crinnion, WJ; Griffin, P.; Stuetz, R.; Cartmell, E. (2005). "The CDC Fourth National Report on Human Exposure to Environmental Chemicals: what it Tells Us about our Toxic Burden and How it Assists Environmental Medicine Physicians". Water Environ. Res. 77 (1): 63–7. doi:10.2175/106143005X41636. JSTOR 25045839. PMID 15765937. 
  11. ^ Food and Drug Administration (17 June 1994). "Federal Register Notice: Tentative Final Monograph for OTC Healthcare Antiseptic Drug Products - June 17, 1994". 
  12. ^ Coia JE, Duckworth GJ, Edwards DI, et al. (May 2006). "Guidelines for the control and prevention of meticillin-resistant Staphylococcus aureus (MRSA) in healthcare facilities". J. Hosp. Infect. 63 Suppl 1: S1–44. doi:10.1016/j.jhin.2006.01.001. PMID 16581155. 
  13. ^ Brady LM, Thomson M, Palmer MA, Harkness JL (March 1990). "Successful control of endemic MRSA in a cardiothoracic surgical unit". Med. J. Aust. 152 (5): 240–5. PMID 2255283. 
  14. ^ Zafar AB, Butler RC, Reese DJ, Gaydos LA, Mennonna PA (June 1995). "Use of 0.3% triclosan (Bacti-Stat) to eradicate an outbreak of methicillin-resistant Staphylococcus aureus in a neonatal nursery". Am J Infect Control 23 (3): 200–8. doi:10.1016/0196-6553(95)90042-X. PMID 7677266. 
  15. ^ Montville, Rebecca; Schaffner, Donald W. (1 November 2011). "A Meta-Analysis of the Published Literature on the Effectiveness of Antimicrobial Soaps". Journal of Food Protection 74 (11): 1875–1882. doi:10.4315/0362-028X.JFP-11-122. PMID 22054188. 
  16. ^ Fuls, Janice L.; Rodgers ND, et al. (April 2008). "Alternative Hand Contamination Technique To Compare the Activities of Antimicrobial and Nonantimicrobial Soaps under Different Test Conditions". Applied and Environmental Microbiology 74 (12): 3739–3744. doi:10.1128/AEM.02405-07. PMC 2446551. PMID 18441107. 
  17. ^ http://www.fda.gov/ForConsumers/ConsumerUpdates/ucm205999.htm
  18. ^ a b c Singer H, Müller S, Tixier C, Pillonel L (December 2002). "Triclosan: occurrence and fate of a widely used biocide in the aquatic environment: field measurements in wastewater treatment plants, surface waters, and lake sediments". Environ. Sci. Technol. 36 (23): 4998–5004. Bibcode:2002EnST...36.4998S. doi:10.1021/es025750i. PMID 12523412. 
  19. ^ Heidler J, Halden RU (January 2007). "Mass balance assessment of triclosan removal during conventional sewage treatment". Chemosphere 66 (2): 362–9. doi:10.1016/j.chemosphere.2006.04.066. PMID 16766013. 
  20. ^ http://www.chemicalbook.com/ChemicalProductProperty_EN_CB5316744.htm[full citation needed]
  21. ^ Latch DE, Packer JL, Stender BL, VanOverbeke J, Arnold WA, McNeill K (March 2005). "Aqueous photochemistry of triclosan: formation of 2,4-dichlorophenol, 2,8-dichlorodibenzo-p-dioxin, and oligomerization products". Environ. Toxicol. Chem. 24 (3): 517–25. doi:10.1897/04-243R.1. PMID 15779749. 
  22. ^ COMMISSION DECISION of 19 March 2010 concerning the non-inclusion of 2,4,4’-trichloro-2’-hydroxydiphenyl ether in the Union list of additives which may be used in the manufacture of plastic materials and articles intended to come into contact with foodstuffs under Directive 2002/72/EC 23.3.2010 Official Journal of the European Union
  23. ^ Triclosan at Household Products Database, U.S. Department of Health and Human Services
  24. ^ "REGULATION (EC) No 1223 /2009 OF THE EUROPEAN PARLIAMENT AND OF THE COUNCIL of 30 November 2009 on cosmetic products". Official Journal of the European Union. 2009. 
  25. ^ Jang CW, Magnuson T (2013). "A novel selection marker for efficient DNA cloning and recombineering in E. coli". In Poteete, Anthony R. PLoS ONE 8 (2): e57075. Bibcode:2013PLoSO...857075J. doi:10.1371/journal.pone.0057075. PMC 3577784. PMID 23437314. 
  26. ^ Russell AD (May 2004). "Whither triclosan?". J. Antimicrob. Chemother. 53 (5): 693–5. doi:10.1093/jac/dkh171. PMID 15073159. 
  27. ^ Heath RJ, Rubin JR, Holland DR, Zhang E, Snow ME, Rock CO (April 1999). "Mechanism of triclosan inhibition of bacterial fatty acid synthesis". J. Biol. Chem. 274 (16): 11110–4. doi:10.1074/jbc.274.16.11110. PMID 10196195. 
  28. ^ Fan F, Yan K, Wallis NG, et al. (November 2002). "Defining and combating the mechanisms of triclosan resistance in clinical isolates of Staphylococcus aureus". Antimicrob. Agents Chemother. 46 (11): 3343–7. doi:10.1128/AAC.46.11.3343-3347.2002. PMC 128739. PMID 12384334. 
  29. ^ Slater-Radosti C, Van Aller G, Greenwood R, et al. (2001). "Biochemical and genetic characterization of the action of triclosan on Staphylococcus aureus". J. Antimicrob. Chemother. 48 (1): 1–6. doi:10.1093/jac/48.1.1. PMID 11418506. 
  30. ^ Chuanchuen R, Karkhoff-Schweizer RR, Schweizer HP (April 2003). "High-level triclosan resistance in Pseudomonas aeruginosa is solely a result of efflux". Am J Infect Control 31 (2): 124–7. doi:10.1067/mic.2003.11. PMID 12665747. 
  31. ^ Chalew, Talia , and Rolf Halden. "Environmental Exposure Of Aquatic And Terrestrial Biota To Triclosan And Triclocarban." JAWRA Journal of the American Water Resources Association 45.1 (2009): 4-13. Wiley Online Library. Web. 17 Feb. 2014. http://onlinelibrary.wiley.com/doi/10.1111/j.1752-1688.2008.00284.x/full
  32. ^ Halden, Rolf U. "On the Need and Speed of Regulating Triclosan and Triclocarban in the United States." Environmental science & technology (2014). http://pubs.acs.org/doi/abs/10.1021/es500495p
  33. ^ Wisk, Joseph D.; Cooper, Keith R. (1990). "Comparison of the toxicity of several polychlorinated dibenzo-p-dioxins and 2,3,7,8-tetrachlorodibenzofuran in embryos of the Japanese medaka (Oryzias latipes)". Chemosphere 20 (3–4): 361–77. doi:10.1016/0045-6535(90)90067-4. 
  34. ^ Buth JM, Steen PO, Sueper C, et al. (June 2010). "Dioxin photoproducts of triclosan and its chlorinated derivatives in sediment cores". Environ. Sci. Technol. 44 (12): 4545–51. Bibcode:2010EnST...44.4545B. doi:10.1021/es1001105. PMID 20476764. 
  35. ^ a b "Environmental Protection Agency". Docket. 27 March 2013. 
  36. ^ a b "Consultation on assessment of the health risk of dioxins; re-evaluation of the tolerable daily intake (TDI): Executive Summary". Food Additives and Contaminants 17 (4): 223–240. 2000. doi:10.1080/713810655. PMID 10912238. 
  37. ^ Clarke, Bradley O., and Stephen R. Smith. "Review of ‘emerging’organic contaminants in biosolids and assessment of international research priorities for the agricultural use of biosolids." Environment international 37.1 (2011): 226-247. http://www.sciencedirect.com/science/article/pii/S0160412010001224
  38. ^ "Triclosan Facts." EPA. Environmental Protection Agency, Web. 17 Feb. 2014. <http://www.epa.gov/oppsrrd1/REDs/factsheets/triclosan_fs.htm
  39. ^ "Triclosan Facts." EPA. Environmental Protection Agency, Web. 17 Feb. 2014. <http://www.epa.gov/oppsrrd1/REDs/factsheets/triclosan_fs.htm
  40. ^ Brausch, John, and Gary Rand. "A review of personal care products in the aquatic environment: Environmental concentrations and toxicity." Chemosphere 82.11 (2011): 1518-1532. ScienceDirect. Web. 17 Feb. 2014. http://ac.els-cdn.com/S0045653510013007/1-s2.0-S0045653510013007-main.pdf?_tid=c685833c-9812-11e3-87db-00000aab0f6c&acdnat=1392669395_a731b9c664c4e98737d93755500c43dd
  41. ^ http://www.breastcancerfund.org/clear-science/radiation-chemicals-and-breast-cancer/triclosan.html
  42. ^ Mathews, Shiny, Shannon Henderson, and Dawn Reinhold. "Uptake and accumulation of antimicrobials, triclocarban and triclosan, by food crops in a hydroponic system." Environmental Science and Pollution Research (2014): 1-9. http://www.ncbi.nlm.nih.gov.proxy.bc.edu/pubmed/24464075
  43. ^ http://www.nrdc.org/living/chemicalindex/triclosan.asp
  44. ^ Halden, Rolf U. "On the Need and Speed of Regulating Triclosan and Triclocarban in the United States." Environmental science & technology (2014). http://pubs.acs.org/doi/abs/10.1021/es500495p
  45. ^ McMurry LM, Oethinger M, Levy SB (August 1998). "Triclosan targets lipid synthesis". Nature 394 (6693): 531–2. Bibcode:1998Natur.394..531M. doi:10.1038/28970. PMID 9707111. 
  46. ^ Supermarkets to ban toxic detergent Rob Edwards, Sunday Herald, 02 November 2003
  47. ^ McBain AJ, Bartolo RG, Catrenich CE, et al. (September 2003). "Exposure of sink drain microcosms to triclosan: population dynamics and antimicrobial susceptibility". Appl. Environ. Microbiol. 69 (9): 5433–42. doi:10.1128/AEM.69.9.5433-5442.2003. PMC 194980. PMID 12957932. 
  48. ^ Aiello AE, Marshall B, Levy SB, Della-Latta P, Larson E (August 2004). "Relationship between triclosan and susceptibilities of bacteria isolated from hands in the community". Antimicrob. Agents Chemother. 48 (8): 2973–9. doi:10.1128/AAC.48.8.2973-2979.2004. PMC 478530. PMID 15273108. 
  49. ^ Yazdankhah SP, Scheie AA, Høiby EA, et al. (2006). "Triclosan and antimicrobial resistance in bacteria: an overview". Microb. Drug Resist. 12 (2): 83–90. doi:10.1089/mdr.2006.12.83. PMID 16922622. 
  50. ^ Triclosan and Antibiotics resistance summary by GreenFacts of an opion by the European Commission Scientific Committee on Consumer Safety (March 2010)
  51. ^ Sifferlin, Alexandra (Aug 15, 2012). "Freaky Clean: Chemical in Antibacterial Soap Weakens Muscle Function". Time. 
  52. ^ a b US Environmental Protection Agency (18 September 2008). "Reregistration Eligibility Decision for Triclosan". Reregistration Eligibility Decision (RED) Document. 
  53. ^ a b Clayton EM, Todd M, Dowd JB, Aiello AE (March 2011). "The impact of bisphenol A and triclosan on immune parameters in the U.S. population, NHANES 2003-2006". Environ. Health Perspect. 119 (3): 390–6. doi:10.1289/ehp.1002883. PMC 3060004. PMID 21062687. Lay summaryScienceDaily (Nov. 30, 2010). 
  54. ^ Sicherer, SH; Leung, DY (January 2013). "Advances in allergic skin disease, anaphylaxis, and hypersensitivity reactions to foods, drugs, and insects in 2012". Journal of Allergy and Clinical Immunology 131 (1): 55–66. doi:10.1016/j.jaci.2012.11.007. PMID 23199604. 
  55. ^ "New Questions Raised On Chemicals In Soaps, Plastics : Shots - Health News Blog : NPR". npr.org. Retrieved 2010-11-30. 
  56. ^ Bhutani T, Jacob SE (May 2009). "Triclosan: a potential allergen in suture-line allergic contact dermatitis". Dermatol Surg 35 (5): 888–9. doi:10.1111/j.1524-4725.2009.01151.x. PMID 19389086. 
  57. ^ Campbell L, Zirwas MJ (December 2006). "Triclosan". Dermatitis 17 (4): 204–7. doi:10.2310/6620.2006.06014. PMID 17150172. 
  58. ^ Yang, Jeniffer (2009-08-21). "Experts concerned about dangers of antibacterial products". Globe and Mail. Retrieved 2009-08-25. 
  59. ^ a b Rule KL, Ebbett VR, Vikesland PJ (May 2005). "Formation of chloroform and chlorinated organics by free-chlorine-mediated oxidation of triclosan". Environ. Sci. Technol. 39 (9): 3176–85. doi:10.1021/es048943. PMID 15926568. 
  60. ^ Dioxins
  61. ^ US Pharmacopoeia National Formulary. United States Pharmacopeial. 2012. ISBN 1936424126. 
  62. ^ "ADA.org: ADA News: Triclosan study not relevant to toothpaste". ada.org. Archived from the original on 2007-10-24. Retrieved 2010-08-16. 
  63. ^ Ricart M, Guasch H, Alberch M, et al. (November 2010). "Triclosan persistence through wastewater treatment plants and its potential toxic effects on river biofilms". Aquat. Toxicol. 100 (4): 346–53. doi:10.1016/j.aquatox.2010.08.010. PMID 20855117. 
  64. ^ Crofton, Kevin M., et al. "Short-term< i> in vivo exposure to the water contaminant triclosan: Evidence for disruption of thyroxine." Environmental Toxicology and Pharmacology 24.2 (2007): 194-197.http://www.sciencedirect.com/science/article/pii/S1382668907000683
  65. ^ http://www.breastcancerfund.org/clear-science/radiation-chemicals-and-breast-cancer/triclosan.html
  66. ^ Clayton EM, Todd M, Dowd JB, Aiello AE (March 2011). "The impact of bisphenol A and triclosan on immune parameters in the U.S. population, NHANES 2003-2006". Environ. Health Perspect. 119 (3): 390–6. doi:10.1289/ehp.1002883. PMC 3060004. PMID 21062687. 
  67. ^ Moss T, Howes D, Williams FM (April 2000). "Percutaneous penetration and dermal metabolism of triclosan (2,4, 4'-trichloro-2'-hydroxydiphenyl ether)". Food Chem. Toxicol. 38 (4): 361–70. doi:10.1016/S0278-6915(99)00164-7. PMID 10722890. 
  68. ^ Adolfsson-Erici M, Pettersson M, Parkkonen J, Sturve J (March 2002). "Triclosan, a commonly used bactericide found in human milk and in the aquatic environment in Sweden". Chemosphere 46 (9–10): 1485–9. doi:10.1016/S0045-6535(01)00255-7. PMID 12002480. 
  69. ^ Edvardsson S, Burman LG, Adolfsson-Erici M, Bäckman N. "Risker och nytta med triklosan i tandkräm" [Risks and benefits of triclosan in toothpaste]. Tandläkartidningen (in German) 97 (10): 58–64. 
  70. ^ Start ~ Naturskyddsföreningen
  71. ^ Zorrilla LM, Gibson EK, Jeffay SC, et al. (January 2009). "The effects of triclosan on puberty and thyroid hormones in male Wistar rats". Toxicol. Sci. 107 (1): 56–64. doi:10.1093/toxsci/kfn225. PMID 18940961. 
  72. ^ Cullinan MP, Palmer JE, Carle AD, West MJ, Seymour GJ (February 2012). "Long term use of triclosan toothpaste and thyroid function". Sci. Total Environ. 416: 75–9. doi:10.1016/j.scitotenv.2011.11.063. PMID 22197412. 
  73. ^ Cherednichenko G, Zhang R, Bannister RA, et al. (August 2012). "Triclosan impairs excitation-contraction coupling and Ca2+ dynamics in striated muscle". Proc. Natl. Acad. Sci. U.S.A. 109 (35): 14158–63. Bibcode:2012PNAS..10914158C. doi:10.1073/pnas.1211314109. PMC 3435154. PMID 22891308. 
  74. ^ Halden, Rolf U. "On the Need and Speed of Regulating Triclosan and Triclocarban in the United States." Environmental science & technology (2014). http://pubs.acs.org/doi/abs/10.1021/es500495p
  75. ^ Fiss EM, Rule KL, Vikesland PJ (April 2007). "Formation of chloroform and other chlorinated byproducts by chlorination of triclosan-containing antibacterial products". Environ. Sci. Technol. 41 (7): 2387–94. Bibcode:2007EnST...41.2387F. doi:10.1021/es062227l. PMID 17438791. 
  76. ^ "Plain soap as effective as antibacterial but without the risk". Retrieved 2007-08-17. 
  77. ^ Kim JS, Kuk E, Yu KN, et al. (March 2007). "Antimicrobial effects of silver nanoparticles". Nanomedicine 3 (1): 95–101. doi:10.1016/j.nano.2006.12.001. PMID 17379174. 
  78. ^ Halden, Rolf U. "On the Need and Speed of Regulating Triclosan and Triclocarban in the United States." Environmental science & technology (2014). http://pubs.acs.org/doi/abs/10.1021/es500495p
  79. ^ Halden, Rolf U. "On the Need and Speed of Regulating Triclosan and Triclocarban in the United States." Environmental science & technology (2014). http://pubs.acs.org/doi/abs/10.1021/es500495p
  80. ^ Halden, Rolf U. "On the Need and Speed of Regulating Triclosan and Triclocarban in the United States." Environmental science & technology (2014). http://pubs.acs.org/doi/abs/10.1021/es500495p
  81. ^ Halden, Rolf U. "On the Need and Speed of Regulating Triclosan and Triclocarban in the United States." Environmental science & technology (2014). http://pubs.acs.org/doi/abs/10.1021/es500495p
  82. ^ Halden, Rolf U. "On the Need and Speed of Regulating Triclosan and Triclocarban in the United States." Environmental science & technology (2014). http://pubs.acs.org/doi/abs/10.1021/es500495p
  83. ^ Halden, Rolf U. "On the Need and Speed of Regulating Triclosan and Triclocarban in the United States." Environmental science & technology (2014). http://pubs.acs.org/doi/abs/10.1021/es500495p
  84. ^ Halden, Rolf U. "On the Need and Speed of Regulating Triclosan and Triclocarban in the United States." Environmental science & technology (2014). http://pubs.acs.org/doi/abs/10.1021/es500495p
  85. ^ Halden, Rolf U. "On the Need and Speed of Regulating Triclosan and Triclocarban in the United States." Environmental science & technology (2014). http://pubs.acs.org/doi/abs/10.1021/es500495p

Further reading[edit]

  • Toxicological Sciences, 2009, 107 (1): 56-64, "The Effects of Triclosan on Puberty and Thyroid Hormones in Male Wistar Rats"
  • Reproductive Toxicology, Apr 2009, 27(2):177-185, "Alteration of testicular steroidogenesis and histopathology of reproductive system in male rats treated with triclosan"

External links[edit]