Toxicity triclosan

Bisphenols are composed of two phenolic groups connected by various linkages. Hydroxy halogenated derivatives, such as hexachlorophane (Fig. 10.7D) and triclosan, are the most active microbiologically, but are bacteriostatic at use-concentrations and have little antipseudomonal activity. The use of hexachlorophane is also limited by its serious toxicity. Both hexachlorophane and trichlosan have limited application in medicated soaps and washing creams. 

Results for the prediction of oral toxicity on rat are shown in Table 14. Bold values indicated that prediction is not reliable. Table includes also a limited number of experimental results provided by the model training dataset (some data are extracted from ChemID database). Globally, values show a high degree of concurrence. The only exceptions are the predictions of triclosan and methylisothia-zolinone toxicity for triclosan, prediction made by T.E.S.T. is more conservative than ToxSuite and experimental values while for methylisothiazolinone predicted values from T.E.S.T and ToxSuite are variable. 

Inoue et al. [41] studied the elimination of triclosan by MnP from P. chrysosporium, and LAC from T. versicolor. MnP (0.5 nkat mL-1) was the most efficient, achieving a removal of 94% after 30 min and almost complete after 60 min, while LAC (2.0 nkat mL-1) and LAC-HBT removed triclosan at 51% and 66%, respectively. Moreover, the treatment with MnP resulted in the complete loss of bacterial inhibition activity after 30 min and reduced the algal growth inhibition by 90% after 60 min. Similar results were obtained by Kim and Nicell [40] with LAC from T. versicolor after 6 h, with concomitant reduction in toxicity even without mediators. 

Fang JL, Stingley RL, Beiand FA, Harrouk W, Lumpkins DL, Howard P (2010) Occurrence, efficacy, metabolism, and toxicity of triclosan. J Environ Sci Health C Environ Carcinog Ecotoxicol Rev 28 147-171... 

Dann AB, Hontela A (2011) Triclosan environmental exposure, toxicity and mechanisms of action. J Appl Toxicol 31 285-311... 

Triclosan is a broad-spectrum antimicrobial compound. It was originally used in soaps, antiperspirants, and cosmetic toiletries as a germicide. Today, triclosan is incorporated into toothpaste because of its wide spectrum of antimicrobial activities and low toxicity. 

Orvos D.R., D.J. Versteeg, J. Inauen, M. Capdevielle, A. Rothenstein, and V. Cumungham (2002). Aquatic toxicity of triclosan. Environmental Toxicology and Chemistry 21 1338-1349. 

Triclosan (2,4,4,-trichloro-2/-hydroxydiphenylether) is an antiseptic suitable for formulation in a W/O emulsion with excellent antibacterial activity in vitro and in vivo against S. aureus, Klebsiella and Proteus species 26 In addition, it has been shown to be effective for eradication of MRSA as well as fungi. Triclosan does not have irritative, phototoxic or allergic, nor mutagenic or teratogenic potential the toxicity in general is low and so is the sensitizing potential.27-29 Triclosan and similar additives (e.g., triclocarban) have demonstrated antibacterial and antiinflammatory efficacy when used as an antiseptic wash.28,30... 

PCDEs are converted to toxic PCDFs in photochemical reactions [71] and metabolism of PCDEs could in theory also lead to the formation of PCDDs when both 2- and 2 -positions are hydroxylated and then dehydrated. No PCDDs and PCDFs, however, were detected in the urinary and fecal extracts of rats fed with PCDEs [18]. Metabolic formation of PCDDs or PCDFs was neither observed in the case of a predioxin, Triclosan. 

Soaps are used in virtually every household every day. Basic soap is produced by the saponification (hydrolysis with sodium hydroxide) of animal or vegetable fats and has little toxicity. Soaps commonly used, however, contain additives to give them deodorant and antimicrobial properties. Such soaps may contain chloroxylenol, phenol, triclosan, methylisothiazolinone (MIT), and other toxicants that are released into water streams)40 ... 

Hazardous Decomp. Prods. Heated to decomp., emits toxic fumes of Cr and NOx Storage Subject to photolysis Uses Systemic herbicide Triclosan... 

Triclosan, shown in Figure 1, is a polychlorinated diphenyl ether and is similar in structure to common herbicides. Triclosan has been in use for more than 30 years as a broad spectrum antibacterial agent due to its ability to block one step in bacterial fatty acid synthesis (/). In addition to its high toxicity to bacteria, triclosan is also acutely toxic to fish, protozoa, and other aquatic organisms (2). 

In addition to the disposal problems associated widi powdered triclosan, there are also disposal problems associated with triclosan containing organic solvents. Solutions containing up to 2.5% triclosan in ethanol or isopropanol are commonly used for disinfecting medical equipment. Because of the high toxicity of triclosan to bacteria, and the recalcitrance of triclosan in activated sludge treatment systems, disposal of these solutions into sanitary sewers may result in... 

The Microtox assay was used to monitor the decline in toxicity of die triclosan solutions as a fhnction of the electrolysis time. This test monitors die... 

All reaction products in both ethanol and aqueous solutions were much less toxic than triclosan itself. Microtox EC50 values were calculated for effluent sanqiles from the flow-dirough reactor. Figure 9 shows how the decline in toxicity of the solutions closely parallels the decline in triclosan concentration. 

Figure 9. Normalized toxicity and triclosan concentrations in ethanol and...

The cationic P-CD polymers were used to include antibiotics butylparaben (1) and triclosan (2) [22, 23]. These both antibiotics are nonionic they show a broad spectrum activity to microorganisms and their toxicity is low [24]. They are used as disinfecting species in food, cosmetic and drug industries. The sizes of 1 and 2 are suitable for inclusion into P-CD cavities. Upon forming complexes with cationic P-CD polymer their very low water... 

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