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Triclosan
Kinds of Triclosan Selected AbstractsTriclosan: A Potential Allergen in Suture-Line Allergic Contact DermatitisDERMATOLOGIC SURGERY, Issue 5 2009TINA BHUTANI MD No abstract is available for this article. [source] Aquatic photochemistry of chlorinated triclosan derivatives: Potential source of polychlorodibenzo- P -dioxins,ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 12 2009Jeffrey M. Buth Abstract Triclosan (TCS; 5-chloro-2-(2,4-dichlorophenoxy)phenol), a common antimicrobial agent, may react with residual chlorine in tap water during transport to wastewater treatment plants or during chlorine disinfection of wastewater, generating chlorinated TCS derivatives (CTDs): 4,5-dichloro-2-(2,4-dichlorophenoxy)phenol (4-Cl-TCS), 5,6-dichloro-2-(2,4-dichlorophenoxy)phenol (6-C1-TCS), and 4,5,6-trichloro-2-(2,4-dichlorophenoxy)phenol (4,6-Cl-TCS). The photochemistry of CTDs was investigated due to the potential formation of polychlorodibenzo- p -dioxin (PCDD) photoproducts. Photolysis rates were highly dependent upon CTD speciation, because the phenolate species degraded 44 to 586 times faster than the phenol forms. Photolysis quantum yield values for TCS, 4-Cl-TCS, 6-Cl-TCS, and 4,6-Cl-TCS of 0.39, 0.07, 0.29, and 0.05, respectively, were determined for the phenolate species. Photolyses performed in Mississippi River and Lake Josephine (USA) waters gave similar quantum yields as buffered, pure water at the same pH, indicating that indirect photolysis processes involving photosensitization of dissolved organic matter are not competitive with direct photolysis. The photochemical conversion of the three CTDs to PCDDs under solar irradiation was confirmed in natural and buffered, pure water at yields of 0.5 to 2.5%. The CTD-derived PCDDs possess higher toxicities than 2,8-dichlorodibenzo- p -dioxin, a previously identified photoproduct of TCS, due to their higher chlorine substitution in the lateral positions. The load of TCS- and CTD-derived PCDDs to United States surface waters is estimated to be between 46 and 92 g toxicity equivalent units per year. Other identified photoproducts of each CTD were 2,4-dichlorophenol and reductive dechlorination products. [source] Fate and effects of triclosan in activated sludgeENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 7 2002Thomas W. Federle Abstract Triclosan (TCS; 5-chloro-2-[2,4-dichloro-phenoxy]-phenol) is a widely used antimicrobial agent. To understand its fate during sewage treatment, the biodegradation and removal of TCS were determined in activated sludge. In addition, the effects of TCS on treatment processes were assessed. Fate was determined by examining the biodegradation and removal of TCS radiolabeled with 14C in the 2,4-dichlorphenoxy ring in laboratory batch mineralization experiments and bench-top continuous activated-sludge (CAS) systems. In batch experiments with unacclimated sludge, TCS was mineralized to 14CO2, but the total yield varied as a function of test concentration. Systems that were redosed with TCS exhibited more extensive and faster mineralization, indicating that adaptation was a critical factor determining the rate and extent of biodegradation. In a CAS study in which the influent level of TCS was incrementally increased from 40 ,g/L to 2,000 ,g/L, removal of the parent compound exceeded 98.5% and removal of total radioactivity (parent and metabolites) exceeded 85%. Between 1.5 and 4.5% of TCS in the influent was sorbed to the wasted solids, whereas >94% underwent primary biodegradation and 81 to 92% was mineralized to CO2 or incorporated in biomass. Increasing levels of TCS in the influent had no major adverse effects on any wastewater treatment process, including chemical oxygen demand, biological oxygen demand, and ammonia removal. In a subsequent experiment, a CAS system, acclimated to TCS at 35 ,g/L, received two separate 4-h shock loads of 750 ,g/L TCS. Neither removal of TCS nor treatment processes exhibited major adverse effects. An additional CAS study was conducted to examine the removal of a low level (10 ,g/L) of TCS. Removal of parent equaled 94.7%, and biodegradation remained the dominant removal mechanism. A subsequent series of CAS experiments examined removal at four influent concentrations (7.5, 11, 20, and 50 ,g/L) of TCS and demonstrated that removal of parent ranged from 98.2 to 99.3% and was independent of concentration. Although TCS removal across all experiments appeared unrelated to influent concentration, removal was significantly correlated (r2 = 0.87) with chemical oxygen demand removal, indicating that TCS removal was related to overall treatment efficiency of specific CAS units. In conclusion, the experiments show that TCS is extensively biodegraded and removed in activated-sludge systems and is unlikely to upset sewage treatment processes at levels expected in household and manufacturing wastewaters. [source] Aquatic toxicity of triclosanENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 7 2002David R. Orvos Abstract The aquatic toxicity of triclosan (TCS), a chlorinated biphenyl ether used as an antimicrobial in consumer products, was studied with activated-sludge microorganisms, algae, invertebrates, and fish. Triclosan, a compound used for inhibiting microbial growth, was not toxic to wastewater microorganisms at concentrations less than aqueous solubility. The 48-h Daphnia magna median effective concentration (EC50) was 390 ,g/L and the 96-h median lethal concentration values for Pimephales promelas and Lepomis macrochirus were 260 and 370 ,g/L, respectively. A no-observed-effect concentration (NOEC) and lowest-observed-effect concentration of 34.1 ,g/L and 71.3 ,g/L, respectively, were determined with an early life-stage toxicity test with Onco-rhynchus mykiss. During a 96-h Scenedesmus study, the 96-h biomass EC50 was 1.4 ,g/L and the 96-h NOEC was 0.69 ,g/L. Other algae and Lemna also were investigated. Bioconcentration was assessed with Danio rerio. The average TCS accumulation factor over the five-week test period was 4,157 at 3 ,g/L and 2,532 at 30 ,g/L. Algae were determined to be the most susceptible organisms. Toxicity of a TCS-containing wastewater secondary effluent to P. promelas and Ceriodaphnia was evaluated and no observed differences in toxicity between control and TCS-treated laboratory units were detected. The neutral form of TCS was determined to be associated with toxic effects. Ionization and sorption will mitigate those effects in the aquatic compartment. [source] Probabilistic risk evaluation for triclosan in surface water, sediments, and aquatic biota tissuesINTEGRATED ENVIRONMENTAL ASSESSMENT AND MANAGEMENT, Issue 3 2010Jennifer Lyndall Abstract Triclosan, an antimicrobial compound used in personal care products, occurs in the aquatic environment due to residual concentrations in municipal wastewater treatment effluent. We evaluate triclosan-related risks to the aquatic environment, for aquatic and sediment-dwelling organisms and for aquatic-feeding wildlife, based on measured and modeled exposure concentrations. Triclosan concentrations in surface water, sediment, and biota tissue are predicted using a fugacity model parameterized to run probabilistically, to supplement the limited available measurements of triclosan in sediment and tissue. Aquatic toxicity is evaluated based on a species sensitivity distribution, which is extrapolated to sediment and tissues assuming equilibrium partitioning. A probabilistic wildlife exposure model is also used, and estimated doses are compared with wildlife toxicity benchmarks identified from a review of published and proprietary studies. The 95th percentiles of measured and modeled triclosan concentrations in surface water, sediment, and biota tissues are consistently below the 5th percentile of the respective species sensitivity distributions, indicating that, under most scenarios, adverse affects due to triclosan are unlikely. Integr Environ Assess Manag 2010;6:419,440. © 2010 SETAC [source] In vitro stability of triclosan in dentifrice under simulated use conditionINTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 5 2007Z. Hao Synopsis Triclosan has been formulated into a dentifrice at a 0.3% level to enhance the antibacterial function of the dentifrice, to improve oral health and to decrease the daily malodor inside the mouth cavity. The hypothesis that chloroform may be generated from triclosan when contacted with chlorinated drinking water has challenged our guarantee of safe use of triclosan in oral care products, especially in Colgate Total® toothpaste. Currently, there was no available analytical method to detect chloroform levels under the use conditions expected during daily tooth brushing. To fill this gap and to continue guaranteeing that our customers can safely use Colgate Total® toothpaste products, a gas chromatography,single ion monitoring,mass spectrometry method for detecting chloroform in artificial saliva media has been developed. The limit of detection (LOD) and limit of quantitation are about 41 and 130 ppb, respectively. This LOD level is lower than the current Environmental Protection Agency trihalomethanes contamination limit, which is required for our daily drink water. Our in vitro study indicated that Colgate Total® does not form detectable chloroform levels (41 ppb) over the range of expected consumer-brushing times while using normal chlorinated drinking water. Résumé Un dentifrice contenant une concentration de 0.3% de Triclosan a été formulé dans le but de renforcer les propriétés antibactériennes du produit, d'améliorer l'hygiène buccale et de diminuer les mauvaises odeurs quotidiennes de la cavité buccale. L'hypothèse que du chloroforme peut se former à partir du Triclosan au contact de l'eau douce chlorée jette un doute sur la garantie de sécurité d'utilisation du Triclosan dans les produits oraux, en particulier dans la pâte dentifrice Colgate Total®. On ne dispose actuellement d'aucune méthode analytique permettant de détecter le chloroforme dans des conditions habituelles d'utilisation qui correspondent au brossage quotidien des dents. Pour y remédier et pour continuer à garantir à nos clients la sécurité d'utilisation de la pâte dentifrice Colgate Total®, une méthode GC-SIM-MS capable de détecter le chloroforme dans une salive artificielle a été développée. La limite de détection (LOD) et la limite de quantification (LOQ) sont respectivement d'environ de 41 et 130 ppb. Cette valeur de LOD est inférieure à la limite de contamination en trihalométhane requise pour l'eau douce journalière par l'Environnemental Protection Agency (EPA). Notre étude in vitro montre que Colgate Total® ne génère pas de chloroforme à une concentration détectable (41 ppb) pendant la durée requise d'un brossage avec l'utilisation d'eau potable chlorée. [source] X-ray crystallographic analysis of the complexes of enoyl acyl carrier protein reductase of Plasmodium falciparum with triclosan variants to elucidate the importance of different functional groups in enzyme inhibitionIUBMB LIFE, Issue 6 2010Koustav Maity Abstract Triclosan, a well-known inhibitor of Enoyl Acyl Carrier Protein Reductase (ENR) from several pathogenic organisms, is a promising lead compound to design effective drugs. We have solved the X-ray crystal structures of Plasmodium falciparum ENR in complex with triclosan variants having different substituted and unsubstituted groups at different key functional locations. The structures revealed that 4 and 2, substituted compounds have more interactions with the protein, cofactor, and solvents when compared with triclosan. New water molecules were found to interact with some of these inhibitors. Substitution at the 2, position of triclosan caused the relocation of a conserved water molecule, leading to an additional hydrogen bond with the inhibitor. This observation can help in conserved water-based inhibitor design. 2, and 4, unsubstituted compounds showed a movement away from the hydrophobic pocket to compensate for the interactions made by the halogen groups of triclosan. This compound also makes additional interactions with the protein and cofactor which compensate for the lost interactions due to the unsubstitution at 2, and 4,. In cell culture, this inhibitor shows less potency, which indicates that the chlorines at 2, and 4, positions increase the ability of the inhibitor to cross multilayered membranes. This knowledge helps us to modify the different functional groups of triclosan to get more potent inhibitors. © 2010 IUBMB IUBMB Life, 467,476, 2010 [source] Triclosan reduces microsomal prostaglandin E synthase-1 expression in human gingival fibroblastsJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 1 2005M. Mustafa Abstract Objective: The effect of triclosan (2,4,4,-trichloro-2,-hydroxydiphenyl ether) on the expression of cyclooxygenase-2 (COX-2) and microsomal prostaglandin E synthase-1 (mPGES-1) and on the translocation of the nuclear factor- ,B (NF- ,B) in relation to prostaglandin E2 (PGE2) production was investigated in human gingival fibroblasts challenged with tumor necrosis factor , (TNF,). Methods: Fibroblasts were established from gingival biopsies obtained from six children. COX-2 mRNA and protein expression was quantified using mRNA quantitation and enzyme immunometric assay kits. mPGES-1 mRNA was analysed by RT-PCR, mPGES-1 protein and NF-,B translocation by immunoblotting. PGE2 was determined by radioimmunoassay. Results: The cytokine TNF, enhanced the expression of mRNA as well as the protein levels of both COX-2 and mPGES-1 and subsequently the production of PGE2 in gingival fibroblasts. Treatment of gingival fibroblasts with triclosan (1 ,g/ml) significantly reduced the stimulatory effect of TNF, (10 ng/ml) on the expression of mPGES-1 at both the mRNA and the protein level by an average of 21% and 43%, respectively, and subsequently the production of PGE2 (p<0.01). Triclosan did not, however, affect the translocation of NF- ,B or the expression of COX-2 in TNF,- stimulated cells. Conclusion: The results show that triclosan reduces the augmented biosynthesis of PGE2 by inhibiting the mRNA and the protein expression of mPGES-1 in gingival fibroblasts. This finding may partly explain the anti-inflammatory effect of the agent previously reported in clinical studies. [source] Effect of an amine-fluoride-triclosan mouthrinse on plaque regrowth and biofilm vitalityJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 4 2002Nicole B. Arweiler Abstract Background: The purpose of this double-blind, prospective, latin-square crossover randomised study was to examine the efficacy of a mouthrinse solution containing a combination of triclosan, amine fluoride and sodium fluoride on supragingival plaque regrowth compared to a placebo and a chlorhexidine solution. Methods: 12 volunteers refrained after professional oral prophylaxis from all mechanical hygiene measures for the following 96 h and rinsed instead cross-over in a randomised order with either chlorhexidine dicluconate (0.2%, positive control), a verum solution (0.5% amine fluoride, 0.028% sodium fluoride, 0.03% triclosan) or a placebo solution. The plaque index was assessed after 24 and 96 h (PI 1, PI 2) and the plaque area (PA) photographed and calculated after 96 h of undisturbed plaque regrowth. Moreover plaque samples were taken after 24 and 96 h and examined with the vital fluorescence technique to assess the vitality of the biofilm microbiota (VF 1, VF 2). Results: The amine-fluoride-triclosan solution reduced the clinical parameters (PI and PA) as well as the vitality of the plaque flora (VF) significantly when compared to the placebo solution. The verum reached a 36.5% (p<0.05) and a 39.8% reduction (p<0.0001) in PI 1 and PI 2, respectively, concomittant with a reduction of 23.8% and 32.2% (p<0.001) in VF 1 and VF 2 and of 46.9% (p<0.0001) in PA at day 4. This was less than the reductions found with the positive control, i.e., the 0.2% chlorhexidine solution (54.2% and 71.1% reduction in PI 1 and PI 2, 40.0% and 53.4% in VF 1 and VF 2 and 71.5% in PA). However, significant differences between both active solutions were only established for PI 2 and PA. Conclusion: During 4-day plaque regrowth the amine-fluoride-triclosan product displayed a significant antibacterial and plaque-reducing action in comparison to the control. Zusammenfassung Hintergrund: Der Zweck dieser prospektiven, gekreuzten, randomisierten Doppeltblindstudie war die Überprüfung der Effektivität einer Mundspüllösung, die eine Kombination von Triclosan, Aminfluorid und Natriumfluorid enthielt, auf die Neuetablierung der supragingivalen Plaque im Vergleich zu einem Placebo und einer Chlorhexidinlösung. Methoden: 12 Probanden wurde nach einer professionellen Prophylaxe jegliche mechanische Hygiene für die folgenden 96 Stunden untersagt. Sie spülten dafür überkreuzt in einer zufälligen Reihenfolge entweder mit Chlorhexidindiglukonat (0.2%, positive Kontrolle), einer Versuchslösung (0.5% Aminfluorid, 0.028% Natriumfluorid, 0.03% Triclosan) oder einer Placebolösung. Der Plaque-index wurde nach 24 Stunden und 96 Stunden erhoben (PI 1, PI 2). Die Plaquefläche (PA) wurde fotografiert und berechnet nach 96 Stunden des ungestörten Plaquewachstums. Zusätzlich wurden Plaqueproben nach 24 und 96 Stunden entnommen und mit der Vitalfluoreszenztechnik die Vitalität der Mikroflora des Biofilms bestimmt (VF 1, VF 2). Ergebnisse: Die Aminfluorid-Triclosan-Lösung reduzierte die klinischen Parameter (PI und PA) sowie die Vitalität der Plaqueflora (VF) signifikant, im Vergleich mit der Placebolösung. Die Versuchslösung erreichte eine 36.5%ige (p<0.05) und eine 39.8%ige Reduktion (p<0.001) bei PI 1 und PI 2, verbunden mit einer Reduktion von 23.8% und 32.2% (p<0.01) bei VF 1 und VF 2 und 46.9% (p<0.0001) bei PA am Tag 4. Dies war geringer als die Reduktionen, die mit der positiven Kontrolle gefunden wurden, d.h. mit der 0.2%igen Chlorhexidin-Lösung (54.2% und 71.1% Reduktion bei PI 1 und PI 2, 40.0% und 53.4% bei VF 1 und VF 2 sowie 71.5% bei PA). Jedoch wurden signifikante Differenzen zwischen beiden aktiven Lösungen nur bei PI 2 und PA gefunden. Zusammenfassung: Während eines 4tägigen Plaquewachstums zeigte das Aminfluorid-Triclosan-Produkt eine signifikante antibakterielle und plaquereduzierende Wirkung im Vergleich zu der Kontrolle. Résumé Origine: Le but de cette étude randomisée, croisée, prospective en double aveugle a été d'examiner l'efficacité d'une solution contenant une association de fluorure d'amine, de fluorure de sodium et de triclosan sur l'accumulation de la plaque dentaire sus-gingivale comparée à un placebo et à une solution de chlorhexidine (CHX). Méthodes: Après un nettoyage professionnel, 12 volontaires ont arrêté toutes mesures d'hygiène buccale pendant 96 h. Ils se sont rinçés de manière randomisée et croisée avec du digluconate de CHX 0.2%, une solution verum (fluorure d'amine 0.5%, fluorure de sodium 0.028% et triclosan 0.03%) ou une solution placebo. L'indice de plaque a été mesurée après 24 h (Pli 1) et 96 h (Pli 2) et la zone de plaque (PA) photographiée et calculée après 96 h. Des échantillons de plaque dentaire ont été prélevés après 24 h (VF 1) et 96 h (VF 2) et examinés par la technique de vitalité de fluorescence, pour mesurer la vitalité de la flore du biofilm. Résultats: La solution flurorure d'amine/triclosan réduisait significativement les paramètres cliniques (Pli et PA) ainsi que la vitalité de la flore (VF) comparée à la solution placebo. Le vérum atteignait des réductions respectives de 37% (p<0.05) et 40% (p<0.0001) des Pli 1 et Pli 2 concomitantes avec une réduction de 24 et 32% (p<0.001) de VF 1 et VF 2 et de 47% (p<0.0001) de PA au jour 4. Ceci était inférieur aux réductions trouvées dans le contrôle positif, c.-à-d. la CHX 0.2% (54 et 71% de réduction de Pli 1 et Pli 2, 40 et 53% de VF 1 et VF 2, et 72% de PA). Cependant, les différences significatives entre les deux solutions actives ont été mises en évidence uniquement pour Pli2 et PA. Conclusion: Durant cette courte croissance de la plaque dentaire, le produit fluorure d'amine/triclosan montrait une action antibactérienne et anti-plaque supérieure à celle du contrôle. [source] Environmental Exposure of Aquatic and Terrestrial Biota to Triclosan and Triclocarban,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 1 2009Talia E. A. Chalew Abstract:, The synthetic biocides triclosan (5-chloro-2-(2,4-dichlorophenoxy)phenol) and triclocarban (3,4,4,-trichlorocarbanilide) are routinely added to a wide array of antimicrobial personal care products and consumer articles. Both compounds can persist in the environment and exhibit toxicity toward a number of biological receptors. Recent reports of toxicological effects in wildlife, human cell cultures, and laboratory animals have heightened the interest in the occurrence of these biocide and related toxic effects. The present study aimed to summarize published environmental concentrations of biocides and contrast them with toxicity threshold values of susceptible organisms. Environmental occurrences and toxicity threshold values span more than six orders of magnitude in concentration. The highest biocide levels, measured in the mid parts-per-million range, were determined to occur in aquatic sediments and in municipal biosolids destined for land application. Crustacea and algae were identified as the most sensitive species, susceptible to adverse effects from biocide exposures in the parts-per-trillion range. An overlap of environmental concentrations and toxicity threshold values was noted for these more sensitive organisms, suggesting potential adverse ecological effects in aquatic environments. Affirmative evidence for this is lacking, however, since studies examining environmental occurrences of biocides vis-à-vis the health and diversity of aquatic species have not yet been conducted. [source] Determination of triclosan metabolites by using in-source fragmentation from high-performance liquid chromatography/negative atmospheric pressure chemical ionization ion trap mass spectrometryRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 13 2010Jian-lin Wu Triclosan is a widely used broad-spectrum antibacterial agent that acts by specifically inhibiting enoyl,acyl carrier protein reductase. An in vitro metabolic study of triclosan was performed by using Sprague-Dawley (SD) rat liver S9 and microsome, while the invivo metabolism was investigated on SD rats. Twelve metabolites were identified by using in-source fragmentation from high-performance liquid chromatography/negative atmospheric pressure chemical ionization ion trap mass spectrometry (HPLC/APCI-ITMS) analysis. Compared to electrospray ionization mass spectrometry (ESI-MS) and tandem mass spectrometry (MS/MS) that gave little fragmentation for triclosan and its metabolites, the in-source fragmentation under APCI provided intensive fragmentations for the structural identifications. The invitro metabolic rate of triclosan was quantitatively determined by using HPLC/ESI-ITMS with the monitoring of the selected triclosan molecular ion. The metabolism results indicated that glucuronidation and sulfonation were the major pathways of phase II metabolism and the hydroxylated products were the major phase I metabolites. Moreover, glucose, mercapturic acid and cysteine conjugates of triclosan were also observed in the urine samples of rats orally administrated with triclosan. Copyright © 2010 John Wiley & Sons, Ltd. [source] Genotoxicity of three mouthwash products, Cepacol®, Periogard®, and Plax®, in the Drosophila wing-spot testENVIRONMENTAL AND MOLECULAR MUTAGENESIS, Issue 8 2007Fábio Rodrigues Abstract Antiseptic mouthwashes used in biofilm control are widely available in the marketplace, despite inconsistent data concerning their genetic and cellular toxicity. In the present study, we investigated the genotoxic potential of three antiseptics currently used for odontologic treatment, Cepacol® (containing cetylpyridinium chloride), Periogard® (chlorhexidine digluconate), and Plax® (triclosan). Genotoxicity was evaluated using the Somatic Mutation and Recombination Test (SMART) in Drosophila melanogaster, employing flies having normal bioactivation (the standard cross) and flies with increased cytochrome P450-dependent biotransformation capacity (the high bioactivation cross). Periogard and Plax produced negative responses in both types of flies; however, Cepacol (75 and 100%) produced positive responses in both the standard and high bioactivation assays, with the genotoxic responses mainly due to the induction of mitotic recombination. Assays performed with ethanol and cetylpirydinium chloride, two major ingredients of Cepacol, indicated that the genotoxity of the mouthwash is likely to be due to ethanol. Environ. Mol. Mutagen., 2007. © 2007 Wiley-Liss, Inc. [source] Emerging pollutants in the North Sea in comparison to Lake Ontario, Canada, dataENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 6 2007Jens Arne Andresen Abstract In the present study, the concentrations and fate of contaminants such as organophosphate flame retardants and plasticizers, musk compounds such as galaxolide (HHCB), tonalide (AHTN), musk ketone and musk xylene, the bactericide triclosan, as well as the metabolites HHCB-lactone and triclosan-methyl were compared in the aqueous phase of the German Bight (North Sea). The concentrations of these compounds were around 1 to 10 ng/L in nearshore areas, and the concentrations were lower in the more pristine areas. The highest concentrations were determined for tris-(2-chloro- isopropyl) phosphate in the North Sea with concentration exceeding 10 ng/L even for the offshore samples. The samples contained 1 to 20 ng/L chlorinated organophosphates, approximately 1 ng/L nonchlorinated organophosphates, and 0.3 to 3 ng/L fragrance compounds. Some samples from Lake Ontario (Canada) were analyzed in comparison. Per capita emissions were calculated for both regions. These emissions were compared and turned out to be very similar for the Canadian and German locations. For the North Sea, some observations concerning stability, dilution, and degradation, as well as sources of the respective substances, were performed. These data indicate that the chlorinated organophosphates and some musk fragrances exhibit half lives exceeding the residence times and thus can be considered to be persistent in this ecosystem. In the German Bight, the river Elbe is the dominating source for the more hydrophilic compounds, such as chlorinated organophosphate flame retardants, which are diluted only into the North Sea. However, for the more lipophilic compounds such as the musk fragrances, different input patterns as well as distribution patterns are relevant, though the river Elbe is still a major source of pollution to the German Bight of the North Sea. The data seem to indicate either relevant inputs further west of the sampling area or mobilization from the sediments. [source] Fate and effects of triclosan in activated sludgeENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 7 2002Thomas W. Federle Abstract Triclosan (TCS; 5-chloro-2-[2,4-dichloro-phenoxy]-phenol) is a widely used antimicrobial agent. To understand its fate during sewage treatment, the biodegradation and removal of TCS were determined in activated sludge. In addition, the effects of TCS on treatment processes were assessed. Fate was determined by examining the biodegradation and removal of TCS radiolabeled with 14C in the 2,4-dichlorphenoxy ring in laboratory batch mineralization experiments and bench-top continuous activated-sludge (CAS) systems. In batch experiments with unacclimated sludge, TCS was mineralized to 14CO2, but the total yield varied as a function of test concentration. Systems that were redosed with TCS exhibited more extensive and faster mineralization, indicating that adaptation was a critical factor determining the rate and extent of biodegradation. In a CAS study in which the influent level of TCS was incrementally increased from 40 ,g/L to 2,000 ,g/L, removal of the parent compound exceeded 98.5% and removal of total radioactivity (parent and metabolites) exceeded 85%. Between 1.5 and 4.5% of TCS in the influent was sorbed to the wasted solids, whereas >94% underwent primary biodegradation and 81 to 92% was mineralized to CO2 or incorporated in biomass. Increasing levels of TCS in the influent had no major adverse effects on any wastewater treatment process, including chemical oxygen demand, biological oxygen demand, and ammonia removal. In a subsequent experiment, a CAS system, acclimated to TCS at 35 ,g/L, received two separate 4-h shock loads of 750 ,g/L TCS. Neither removal of TCS nor treatment processes exhibited major adverse effects. An additional CAS study was conducted to examine the removal of a low level (10 ,g/L) of TCS. Removal of parent equaled 94.7%, and biodegradation remained the dominant removal mechanism. A subsequent series of CAS experiments examined removal at four influent concentrations (7.5, 11, 20, and 50 ,g/L) of TCS and demonstrated that removal of parent ranged from 98.2 to 99.3% and was independent of concentration. Although TCS removal across all experiments appeared unrelated to influent concentration, removal was significantly correlated (r2 = 0.87) with chemical oxygen demand removal, indicating that TCS removal was related to overall treatment efficiency of specific CAS units. In conclusion, the experiments show that TCS is extensively biodegraded and removed in activated-sludge systems and is unlikely to upset sewage treatment processes at levels expected in household and manufacturing wastewaters. [source] Aquatic toxicity of triclosanENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 7 2002David R. Orvos Abstract The aquatic toxicity of triclosan (TCS), a chlorinated biphenyl ether used as an antimicrobial in consumer products, was studied with activated-sludge microorganisms, algae, invertebrates, and fish. Triclosan, a compound used for inhibiting microbial growth, was not toxic to wastewater microorganisms at concentrations less than aqueous solubility. The 48-h Daphnia magna median effective concentration (EC50) was 390 ,g/L and the 96-h median lethal concentration values for Pimephales promelas and Lepomis macrochirus were 260 and 370 ,g/L, respectively. A no-observed-effect concentration (NOEC) and lowest-observed-effect concentration of 34.1 ,g/L and 71.3 ,g/L, respectively, were determined with an early life-stage toxicity test with Onco-rhynchus mykiss. During a 96-h Scenedesmus study, the 96-h biomass EC50 was 1.4 ,g/L and the 96-h NOEC was 0.69 ,g/L. Other algae and Lemna also were investigated. Bioconcentration was assessed with Danio rerio. The average TCS accumulation factor over the five-week test period was 4,157 at 3 ,g/L and 2,532 at 30 ,g/L. Algae were determined to be the most susceptible organisms. Toxicity of a TCS-containing wastewater secondary effluent to P. promelas and Ceriodaphnia was evaluated and no observed differences in toxicity between control and TCS-treated laboratory units were detected. The neutral form of TCS was determined to be associated with toxic effects. Ionization and sorption will mitigate those effects in the aquatic compartment. [source] Probabilistic risk evaluation for triclosan in surface water, sediments, and aquatic biota tissuesINTEGRATED ENVIRONMENTAL ASSESSMENT AND MANAGEMENT, Issue 3 2010Jennifer Lyndall Abstract Triclosan, an antimicrobial compound used in personal care products, occurs in the aquatic environment due to residual concentrations in municipal wastewater treatment effluent. We evaluate triclosan-related risks to the aquatic environment, for aquatic and sediment-dwelling organisms and for aquatic-feeding wildlife, based on measured and modeled exposure concentrations. Triclosan concentrations in surface water, sediment, and biota tissue are predicted using a fugacity model parameterized to run probabilistically, to supplement the limited available measurements of triclosan in sediment and tissue. Aquatic toxicity is evaluated based on a species sensitivity distribution, which is extrapolated to sediment and tissues assuming equilibrium partitioning. A probabilistic wildlife exposure model is also used, and estimated doses are compared with wildlife toxicity benchmarks identified from a review of published and proprietary studies. The 95th percentiles of measured and modeled triclosan concentrations in surface water, sediment, and biota tissues are consistently below the 5th percentile of the respective species sensitivity distributions, indicating that, under most scenarios, adverse affects due to triclosan are unlikely. Integr Environ Assess Manag 2010;6:419,440. © 2010 SETAC [source] Anti-microbial hand washes for domestic use , their effectiveness in vitro and in normal useINTERNATIONAL JOURNAL OF CONSUMER STUDIES, Issue 3 2001Kay Sharp Abstract The killing or removal of microbes from the hands is a critical factor in food safety as many studies have shown the hands to be both an important source of microbes and powerful agents of cross-contamination in hospital and domestic situations. In response to this concern, a number of novel hand-washing products have appeared on the market. These products contain anti-microbial agents and claim to be more effective at removing bacteria than soap bars and conventional liquid soaps. This study attempts to test these claims by comparing the effectiveness of a conventional soap bar, a conventional liquid soap and an anti-microbial liquid soap containing triclosan. In vitro tests demonstrate that the anti-microbial liquid soap is more effective than conventional liquid soaps in reducing the viability of six bacterial species and that this effect is both time and dose dependent. However, when the three soaps were compared for their ability to reduce microbial counts on the hands no differences were observed between the three products. For all three soaps, counts after washing sometimes went up and sometimes down when compared with pre-wash counts. This was the case both when the soaps were used ,normally', that is, with great variation in the time taken, water and soap volumes used and method of washing and after a standardized, rigorous wash recommended in clinical situations. Furthermore, reduction in microbial counts from hands contaminated by handling raw meat was no greater for the anti-microbial than for the conventional liquid soap. [source] In vitro stability of triclosan in dentifrice under simulated use conditionINTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 5 2007Z. Hao Synopsis Triclosan has been formulated into a dentifrice at a 0.3% level to enhance the antibacterial function of the dentifrice, to improve oral health and to decrease the daily malodor inside the mouth cavity. The hypothesis that chloroform may be generated from triclosan when contacted with chlorinated drinking water has challenged our guarantee of safe use of triclosan in oral care products, especially in Colgate Total® toothpaste. Currently, there was no available analytical method to detect chloroform levels under the use conditions expected during daily tooth brushing. To fill this gap and to continue guaranteeing that our customers can safely use Colgate Total® toothpaste products, a gas chromatography,single ion monitoring,mass spectrometry method for detecting chloroform in artificial saliva media has been developed. The limit of detection (LOD) and limit of quantitation are about 41 and 130 ppb, respectively. This LOD level is lower than the current Environmental Protection Agency trihalomethanes contamination limit, which is required for our daily drink water. Our in vitro study indicated that Colgate Total® does not form detectable chloroform levels (41 ppb) over the range of expected consumer-brushing times while using normal chlorinated drinking water. Résumé Un dentifrice contenant une concentration de 0.3% de Triclosan a été formulé dans le but de renforcer les propriétés antibactériennes du produit, d'améliorer l'hygiène buccale et de diminuer les mauvaises odeurs quotidiennes de la cavité buccale. L'hypothèse que du chloroforme peut se former à partir du Triclosan au contact de l'eau douce chlorée jette un doute sur la garantie de sécurité d'utilisation du Triclosan dans les produits oraux, en particulier dans la pâte dentifrice Colgate Total®. On ne dispose actuellement d'aucune méthode analytique permettant de détecter le chloroforme dans des conditions habituelles d'utilisation qui correspondent au brossage quotidien des dents. Pour y remédier et pour continuer à garantir à nos clients la sécurité d'utilisation de la pâte dentifrice Colgate Total®, une méthode GC-SIM-MS capable de détecter le chloroforme dans une salive artificielle a été développée. La limite de détection (LOD) et la limite de quantification (LOQ) sont respectivement d'environ de 41 et 130 ppb. Cette valeur de LOD est inférieure à la limite de contamination en trihalométhane requise pour l'eau douce journalière par l'Environnemental Protection Agency (EPA). Notre étude in vitro montre que Colgate Total® ne génère pas de chloroforme à une concentration détectable (41 ppb) pendant la durée requise d'un brossage avec l'utilisation d'eau potable chlorée. [source] Simultaneous determination of chlorinated bacteriostats in cosmetic and pharmaceutical productsINTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 6 2005L.-H. Wang A high-performance liquid chromatography method has been developed for simultaneous determination of triclosan (2,4,4-trichloro-2-hydroxydiphenyl ether) and triclocarban (3,4,4-trichlorocarbanilide) in cosmetic and pharmaceutical products. The two compounds could be separated on a Nucleosil C18 column and eluted with acetonitrile and water (70:30, v/v) as the mobile phase and detected with a differential refractive index detector. The retention times of triclosan and triclocarban were 5.81 and 2.99 min, respectively. The results obtained were in good agreement with those obtained by a differential pulse voltammetric method. [source] Ingredients in dentifrices and their effect on plaque, gingivitis and mutans streptococciINTERNATIONAL JOURNAL OF DENTAL HYGIENE, Issue 1 2004L Jannesson The main objectives of this thesis were to study: (i) the effect of an enzyme-containing dentifrice (Zendium Dentine®), with addition of xylitol on mutans streptococci (MS) in saliva and dental plaque (Paper I) (ii) the effect of a combination of triclosan and xylitol in a dentifrice (Colgate Total®) on MS in saliva and dental plaque (Paper II), and (iii) the effect of oxybenzone on prostaglandin E2 (PGE2)-production in cell culture and the effect of an oxybenzone-containing dentifrice on plaque, gingivitis and MS (Paper III). In Paper I, the subjects were divided into two test groups: one using a 10% xylitol and the other using a 5% xylitol dentifrice for 3 months. The addition of 10% xylitol to Zendium Dentine® had an inhibitory effect on MS in both saliva and dental plaque, and the effect of xylitol seemed to be dose dependent. In Paper II, three groups were using one of the following dentifrices: (i) Colgate Total® with addition of 10% xylitol; (ii) Colgate Total®; and (iii) Colgate Total® without triclosan and without xylitol. The results showed that the addition of 10% xylitol to Colgate Total® reduced the number of MS in saliva and plaque. This effect was more pronounced at 6 months than at 2 months. In Paper III, the effect of oxybenzone was studied in vitro and in vivo. Human Embryo Palatal Mesenchyme (HEPM) cells were used to test the inhibition of IL-1,-stimulated PGE2 production by different concentrations of oxybenzone. The results revealed that there was no decrease of cell viability up to 50 µm. A dose-dependent inhibition of stimulated PGE2 production was found: 50% inhibition (IC50) was found at 0.6 µm. Paper III also included a double-blind clinical trial testing two fluoride dentifrices: one with the addition of 0.5% oxybenzone and one without. Plaque index was reduced in both groups. There was no difference between the groups. A 25% reduction in gingival index was observed in the oxybenzone group after 6 weeks, compared to 2% in the placebo group, indicating an anti-inflammatory effect of oxybenzone. [source] X-ray crystallographic analysis of the complexes of enoyl acyl carrier protein reductase of Plasmodium falciparum with triclosan variants to elucidate the importance of different functional groups in enzyme inhibitionIUBMB LIFE, Issue 6 2010Koustav Maity Abstract Triclosan, a well-known inhibitor of Enoyl Acyl Carrier Protein Reductase (ENR) from several pathogenic organisms, is a promising lead compound to design effective drugs. We have solved the X-ray crystal structures of Plasmodium falciparum ENR in complex with triclosan variants having different substituted and unsubstituted groups at different key functional locations. The structures revealed that 4 and 2, substituted compounds have more interactions with the protein, cofactor, and solvents when compared with triclosan. New water molecules were found to interact with some of these inhibitors. Substitution at the 2, position of triclosan caused the relocation of a conserved water molecule, leading to an additional hydrogen bond with the inhibitor. This observation can help in conserved water-based inhibitor design. 2, and 4, unsubstituted compounds showed a movement away from the hydrophobic pocket to compensate for the interactions made by the halogen groups of triclosan. This compound also makes additional interactions with the protein and cofactor which compensate for the lost interactions due to the unsubstitution at 2, and 4,. In cell culture, this inhibitor shows less potency, which indicates that the chlorines at 2, and 4, positions increase the ability of the inhibitor to cross multilayered membranes. This knowledge helps us to modify the different functional groups of triclosan to get more potent inhibitors. © 2010 IUBMB IUBMB Life, 467,476, 2010 [source] Triclosan inhibition of acute and chronic inflammatory gene pathwaysJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 5 2010Silvana P. Barros Barros SP, Wirojchanasak S, Barrow DA, Panagakos F, Devizio W, Offenbacher S. Triclosan inhibition of acute and chronic inflammatory gene pathways. J Clin Periodontol 2010; 37: 412,418. doi: 10.1111/j.1600-051X.2010.01548.x. Abstract Aim: We sought to determine whether triclosan (2,4,4,-trichloro-2,-hydroxydiphenylether), an extensively used anti-plaque agent with broad-spectrum anti-microbial activity, with reported anti-inflammatory effects via inhibition of prostaglandin E2 and interleukin 1 (IL-1),, could also more broadly suppress multiple inflammatory gene pathways responsible for the pathogenesis of gingivitis and periodontitis. Materials and Methods: As an exploratory study, the effects of triclosan on the inflammatory gene expression profile were assessed ex vivo using peripheral whole blood samples from eight periodontally healthy donors. Ten-millilitres whole blood aliquots were incubated 2 h with 0.3 ,g/ml Escherichia coli lipopolysaccharide (LPS) with or without 0.5 ,g/ml triclosan. Affymetrix microarray gene expression profiles from isolated leucocytes and pathway-specific quantitative polymerase chain reaction arrays were used to investigate changes in expression of target cytokines and cell signalling molecules. Results: Ex vivo human whole blood assays indicated that triclosan significantly down-regulated the LPS-stimulated expression of Toll-like receptor signalling molecules and other multiple inflammatory molecules including IL-1 and IL-6 and the dampening of signals that activate the T-helper type 1 acquired immune response via suppression of CD70 with concomitant up-regulation of growth factors related to bone morphogenetic protein (BMP)2 and BMP6 synthesis. Conclusions: Anti-inflammatory effects were found in this exploratory survey, including suppression of microbial-pathogen recognition pathway molecules and the suppression of acute and chronic mediators of inflammation. [source] Triclosan reduces microsomal prostaglandin E synthase-1 expression in human gingival fibroblastsJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 1 2005M. Mustafa Abstract Objective: The effect of triclosan (2,4,4,-trichloro-2,-hydroxydiphenyl ether) on the expression of cyclooxygenase-2 (COX-2) and microsomal prostaglandin E synthase-1 (mPGES-1) and on the translocation of the nuclear factor- ,B (NF- ,B) in relation to prostaglandin E2 (PGE2) production was investigated in human gingival fibroblasts challenged with tumor necrosis factor , (TNF,). Methods: Fibroblasts were established from gingival biopsies obtained from six children. COX-2 mRNA and protein expression was quantified using mRNA quantitation and enzyme immunometric assay kits. mPGES-1 mRNA was analysed by RT-PCR, mPGES-1 protein and NF-,B translocation by immunoblotting. PGE2 was determined by radioimmunoassay. Results: The cytokine TNF, enhanced the expression of mRNA as well as the protein levels of both COX-2 and mPGES-1 and subsequently the production of PGE2 in gingival fibroblasts. Treatment of gingival fibroblasts with triclosan (1 ,g/ml) significantly reduced the stimulatory effect of TNF, (10 ng/ml) on the expression of mPGES-1 at both the mRNA and the protein level by an average of 21% and 43%, respectively, and subsequently the production of PGE2 (p<0.01). Triclosan did not, however, affect the translocation of NF- ,B or the expression of COX-2 in TNF,- stimulated cells. Conclusion: The results show that triclosan reduces the augmented biosynthesis of PGE2 by inhibiting the mRNA and the protein expression of mPGES-1 in gingival fibroblasts. This finding may partly explain the anti-inflammatory effect of the agent previously reported in clinical studies. [source] Effect of triclosan dentifrices on mouth volatile sulphur compounds and dental plaque trypsin-like activity during experimental gingivitis developmentJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 12 2002G. R. Nogueira-Filho Abstract Background: The objective of this study was to evaluate the effect of three commercial anti-plaque dentifrices containing 0.3% triclosan + 2% pvm/ma (Colgate Total®), 0.3% triclosan + 0.75% Zn (Signal Global®) and 0.3% triclosan + 5% PPi (Crest Complete®) in comparison with an experimental dentifrice (0.3% triclosan + 2% pvm/ma + 0.75% Zn + 4% PPi) and a control dentifrice without anti-plaque agents on trypsin-like activity in dental plaque (detected by the hydrolysis of [Na-Benzoyl-DL-Anginine p-Nitroanilide (BAPNA)] and volatile sulphur compounds (VSCs) in mouth air during experimental gingivitis development. Method: A 5-step double blind, crossover experimental gingivitis study was conducted on 19 volunteers during a 21-day period. The volunteers refrained from brushing an experimental quadrant of teeth. The dentifrices were applied to those teeth via toothshield three times per day; simultaneously they brushed the other teeth with the same dentifrice. After each period, VSCs in mouth air and BAPNA hydrolysis by dental plaque accumulated in the experimental quadrant were determined. Results: There was an increase (p < 0.05) in VSCs in mouth air when experimental gingivitis was induced in only one quadrant of teeth. None of the dentifrices was able to avoid the increase of VSCs during the experimental gingivitis development. The majority of the antiplaque dentifrices evaluated reduced the increase of VSC formation in comparison with the control (p < 0.05). There was no relationship between the ability of the dentifrices in reducing VSC formation and the inhibition of trypsin-like activity in dental plaque. Conclusions: Anti-plaque dentifrices reduce the increase of VSCs that occurs during the development of experimental gingivitis. [source] Effect of an amine-fluoride-triclosan mouthrinse on plaque regrowth and biofilm vitalityJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 4 2002Nicole B. Arweiler Abstract Background: The purpose of this double-blind, prospective, latin-square crossover randomised study was to examine the efficacy of a mouthrinse solution containing a combination of triclosan, amine fluoride and sodium fluoride on supragingival plaque regrowth compared to a placebo and a chlorhexidine solution. Methods: 12 volunteers refrained after professional oral prophylaxis from all mechanical hygiene measures for the following 96 h and rinsed instead cross-over in a randomised order with either chlorhexidine dicluconate (0.2%, positive control), a verum solution (0.5% amine fluoride, 0.028% sodium fluoride, 0.03% triclosan) or a placebo solution. The plaque index was assessed after 24 and 96 h (PI 1, PI 2) and the plaque area (PA) photographed and calculated after 96 h of undisturbed plaque regrowth. Moreover plaque samples were taken after 24 and 96 h and examined with the vital fluorescence technique to assess the vitality of the biofilm microbiota (VF 1, VF 2). Results: The amine-fluoride-triclosan solution reduced the clinical parameters (PI and PA) as well as the vitality of the plaque flora (VF) significantly when compared to the placebo solution. The verum reached a 36.5% (p<0.05) and a 39.8% reduction (p<0.0001) in PI 1 and PI 2, respectively, concomittant with a reduction of 23.8% and 32.2% (p<0.001) in VF 1 and VF 2 and of 46.9% (p<0.0001) in PA at day 4. This was less than the reductions found with the positive control, i.e., the 0.2% chlorhexidine solution (54.2% and 71.1% reduction in PI 1 and PI 2, 40.0% and 53.4% in VF 1 and VF 2 and 71.5% in PA). However, significant differences between both active solutions were only established for PI 2 and PA. Conclusion: During 4-day plaque regrowth the amine-fluoride-triclosan product displayed a significant antibacterial and plaque-reducing action in comparison to the control. Zusammenfassung Hintergrund: Der Zweck dieser prospektiven, gekreuzten, randomisierten Doppeltblindstudie war die Überprüfung der Effektivität einer Mundspüllösung, die eine Kombination von Triclosan, Aminfluorid und Natriumfluorid enthielt, auf die Neuetablierung der supragingivalen Plaque im Vergleich zu einem Placebo und einer Chlorhexidinlösung. Methoden: 12 Probanden wurde nach einer professionellen Prophylaxe jegliche mechanische Hygiene für die folgenden 96 Stunden untersagt. Sie spülten dafür überkreuzt in einer zufälligen Reihenfolge entweder mit Chlorhexidindiglukonat (0.2%, positive Kontrolle), einer Versuchslösung (0.5% Aminfluorid, 0.028% Natriumfluorid, 0.03% Triclosan) oder einer Placebolösung. Der Plaque-index wurde nach 24 Stunden und 96 Stunden erhoben (PI 1, PI 2). Die Plaquefläche (PA) wurde fotografiert und berechnet nach 96 Stunden des ungestörten Plaquewachstums. Zusätzlich wurden Plaqueproben nach 24 und 96 Stunden entnommen und mit der Vitalfluoreszenztechnik die Vitalität der Mikroflora des Biofilms bestimmt (VF 1, VF 2). Ergebnisse: Die Aminfluorid-Triclosan-Lösung reduzierte die klinischen Parameter (PI und PA) sowie die Vitalität der Plaqueflora (VF) signifikant, im Vergleich mit der Placebolösung. Die Versuchslösung erreichte eine 36.5%ige (p<0.05) und eine 39.8%ige Reduktion (p<0.001) bei PI 1 und PI 2, verbunden mit einer Reduktion von 23.8% und 32.2% (p<0.01) bei VF 1 und VF 2 und 46.9% (p<0.0001) bei PA am Tag 4. Dies war geringer als die Reduktionen, die mit der positiven Kontrolle gefunden wurden, d.h. mit der 0.2%igen Chlorhexidin-Lösung (54.2% und 71.1% Reduktion bei PI 1 und PI 2, 40.0% und 53.4% bei VF 1 und VF 2 sowie 71.5% bei PA). Jedoch wurden signifikante Differenzen zwischen beiden aktiven Lösungen nur bei PI 2 und PA gefunden. Zusammenfassung: Während eines 4tägigen Plaquewachstums zeigte das Aminfluorid-Triclosan-Produkt eine signifikante antibakterielle und plaquereduzierende Wirkung im Vergleich zu der Kontrolle. Résumé Origine: Le but de cette étude randomisée, croisée, prospective en double aveugle a été d'examiner l'efficacité d'une solution contenant une association de fluorure d'amine, de fluorure de sodium et de triclosan sur l'accumulation de la plaque dentaire sus-gingivale comparée à un placebo et à une solution de chlorhexidine (CHX). Méthodes: Après un nettoyage professionnel, 12 volontaires ont arrêté toutes mesures d'hygiène buccale pendant 96 h. Ils se sont rinçés de manière randomisée et croisée avec du digluconate de CHX 0.2%, une solution verum (fluorure d'amine 0.5%, fluorure de sodium 0.028% et triclosan 0.03%) ou une solution placebo. L'indice de plaque a été mesurée après 24 h (Pli 1) et 96 h (Pli 2) et la zone de plaque (PA) photographiée et calculée après 96 h. Des échantillons de plaque dentaire ont été prélevés après 24 h (VF 1) et 96 h (VF 2) et examinés par la technique de vitalité de fluorescence, pour mesurer la vitalité de la flore du biofilm. Résultats: La solution flurorure d'amine/triclosan réduisait significativement les paramètres cliniques (Pli et PA) ainsi que la vitalité de la flore (VF) comparée à la solution placebo. Le vérum atteignait des réductions respectives de 37% (p<0.05) et 40% (p<0.0001) des Pli 1 et Pli 2 concomitantes avec une réduction de 24 et 32% (p<0.001) de VF 1 et VF 2 et de 47% (p<0.0001) de PA au jour 4. Ceci était inférieur aux réductions trouvées dans le contrôle positif, c.-à-d. la CHX 0.2% (54 et 71% de réduction de Pli 1 et Pli 2, 40 et 53% de VF 1 et VF 2, et 72% de PA). Cependant, les différences significatives entre les deux solutions actives ont été mises en évidence uniquement pour Pli2 et PA. Conclusion: Durant cette courte croissance de la plaque dentaire, le produit fluorure d'amine/triclosan montrait une action antibactérienne et anti-plaque supérieure à celle du contrôle. [source] A study to assess the plaque inhibitory action of a newly formulated triclosan toothpasteJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 1 2001J. Moran Abstract Background/aims: Triclosan containing toothpastes have been noted for their potential to inhibit plaque and gingival inflammation. The aim of this study was to determine whether a toothpaste containing triclosan and an enhanced fluoride system would inhibit de novo plaque formation beyond that of a non-triclosan, conventional fluoride toothpaste. Methods: This study used a 4-day plaque regrowth model in which 24 volunteers used toothpaste rinses as the only form of oral hygiene. Following a prophylaxis and a single brushing with the toothpastes, 2× daily rinsing with toothpaste slurries was used over the following 96 h. Results: After 24 h, there was no difference in plaque area between the triclosan paste and its control paste. After 96 h, a reduction in plaque score of 5% was noted for the test toothpaste compared to the control paste which was statistically significant (p=0.028). For plaque area this reduction was increased to 16%, which was also significant (p=0.006). Conclusions: These findings would appear to warrant further investigation into the potential value of the paste in inhibiting both plaque and gingivitis. [source] Resolution of interdental inflammation with 2 different modes of plaque controlJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 12 2000Thomas Kocher Abstract Background, aims: The aim of the study was to assess the effect on existing plaque and gingivitis of an oral hygiene regimen which utilizes triclosan/copolymer and to compare it with a regimen which uses interdental cleaning devices to control the interdental inflammation. Method: For this investigation, 39 subjects were recruited. They were examined for plaque and gingivitis using the criteria of Turesky modification of the Quigley-Hein index and the papillary bleeding index. Plaque and gingivitis were only scored interdentally. Following the baseline examination, the subjects were randomly assigned into 2 groups. The control group used a dentifrice identical to the test dentifrice but without triclosan/copolymer; subjects in this group were taught to brush their teeth with the modified Bass technique and were instructed to additionally use appropriate interdental cleaning devices. The test group used a dentifrice containing triclosan/copolymer (Colgate Total). They were not instructed to use interdental cleaning devices. Results: Both groups were re-examined after 4 weeks, and 4 and 7 months. In both groups, plaque and gingivitis levels were modestly reduced, more pronounced in the anterior and less in the posterior teeth. Conclusions: This investigation demonstrated that a dentifrice containing triclosan in combination with a copolymer can reduce plaque and gingival inflammation to levels comparable to regular interdental cleaning. [source] Effect of triclosan on interferon-, production and major histocompatibility complex class II expression in human gingival fibroblastsJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 10 2000Manal Mustafa Abstract Background, aims: The effect of triclosan (2,4,4,-trichloro-2,-hydroxyl-diphenyl ether) on the production of interferon-, (IFN-,) and the expression of major histocompatibility complex (MHC) class II antigen was studied in human gingival fibroblasts isolated from 4 individuals. Methods/Results: AII cell lines demonstrated high IFN-, production in 24-h cultures of human gingival fibroblasts stimulated by phytohemagglutinin (PHA) (5 ,g/ml). Human gingival fibroblasts showed a high expression of MHC class II when stimulated with 500 and 1000 pg/ml rIFN-, in 7-day cultures. Treatment of the cells with triclosan (0.5 ,g/ml) reduced both IFN-, production and MHC class II expression in human gingival fibroblast cultures. Similar inhibitory effects on IFN-, production and MHC class II expression were observed when the anti-inflammatory agent dexamethazone (1 ,M) was used. Conclusion: The present study further supports the view that the agent has an anti-inflammatory effect in addition to its antibacterial capacity. [source] Do Biocides Select for Antibiotic Resistance?,JOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 2 2000A. D. RUSSELL Some similarities exist between bacterial resistance to antibiotics and to biocides, and gram-negative bacteria that have developed resistance to cationic biocides may also be insusceptible to some antibiotics. Outer membrane changes are believed to be responsible for this non-specific increase in resistance. Efflux, another important resistance mechanism, is associated with the qacA/B gene system in staphylococci that confers low-level resistance to cationic agents including chlorhexidine salts and quaternary ammonium compounds. It has been proposed that the introduction into clinical practice of Chlorhexidine and quaternary ammonium compounds has resulted in the selection of staphylococci containing qacA genes on multiresistance plasmids. A linkage between low-level resistance to triclosan and to antibiotics has recently been claimed to occur in Escherichia coli, with the bisphenol selecting for chromosomally-mediated antibiotic resistance. A key issue in many studies has been the use of biocides at concentrations significantly below those used clinically. It remains to be determined how an increase to low-level resistance to cationic biocides can be held responsible for the selection of antibiotic-resistant bacteria. [source] Triclosan inhibition of mycobacterial InhA in Saccharomyces cerevisiae: yeast mitochondria as a novel platform for in vivo antimycolate assaysLETTERS IN APPLIED MICROBIOLOGY, Issue 4 2010A. Gurvitz Abstract Aims:, To demonstrate the suitability of yeast to act as a novel biotechnological platform for conducting in vivo inhibition assays using drugs with low efficacies towards their mycobacterial targets, such as occurs in the situation with triclosan and InhA. Methods and Results:, A surrogate yeast host represented by Saccharomyces cerevisiae etr1, cells lacking Etr1p, the 2- trans -enoyl-thioester reductase of mitochondrial type 2 fatty acid synthase (FASII), was designed to rely on the Mycobacterium tuberculosis FASII enzyme InhA. Although InhA is 10 000 times less sensitive to the antimicrobial drug triclosan than is bacterial FabI, the respiratory growth of yeast cells depending on InhA was severely affected on glycerol medium containing triclosan. Conclusions:, The yeast system could detect enzyme inhibition despite the use of a drug with only low efficacy. Significance and Impact of the Study:, Tuberculosis affects a third of the human population, and InhA is a major drug target for combating this disease. InhA is inhibited by isoniazid, but triclosan-derived compounds are presently being developed as antimycolates. A demonstration of triclosan inhibition of InhA in yeast represents a meaningful variation in studying this effect in mycobacteria, because it occurred without the potentially confusing aspects of perturbing protein,protein interactions which are presumed vital to mycobacterial FASII, inactivating other important enzymes or eliciting a dedicated transcriptional response in Myco. tuberculosis. [source] | ||||||||||||||||