Bactericidal effects of triclosan in soap both in vitro and in vivo

Ototoxicity of Triclosan: A Rat Model Study

OBJECTIVE

Triclosan is utilized as an antibacterial factor in many industrial products. Although there are many toxic features of triclosan in the literature, there is no study on the effect of triclosan on hearing. The purpose of this study is to determine the effect of triclosan on hearing in rats.

METHODS

In this prospective, experimental animal study, 40 healthy Sprague-Dawley rats with normal response to the distortion-product otoacoustic emission (DPOAE) measurements were divided into four groups. Group 1, as the control group, was given only corn oil, group 2 was given 5 mg/kg triclosan dissolved in corn oil, group 3 was given 10 mg/kg triclosan dissolved in corn oil, and group 4 was given 100 mg/kg triclosan dissolved in corn oil; triclosan and corn oil were administered by oral gavage to all groups.

RESULTS

 In our study, low-dose triclosan did not cause hearing loss, but hearing loss was observed in the group that was given high-dose triclosan (100 mg/kg).

CONCLUSION

These findings suggest that triclosan causes hearing loss in rats. This issue should be investigated further to avoid triclosan ototoxicity in humans.

Bibliometric Analysis: The Effects of Triclosan on Human Health

Triclosan (TCS) is a widely used chemical whose effects on human health remains elusive. TCS may play a role in a variety of health issues, including endocrine dysfunction, irregular embryonic development, and immune suppression. It is possible that TCS's penetrative abilities across all body barriers, including the blood-brain barrier, may make bioaccumulation the primary driver of these issues. In addition, chronic overuse of this chemical in everyday life may further contribute to the already increasing problem of antibiotic resistance. TCS research has steadily increased since its transition from medical to commercial use over the last 50 years. However, there are some clear gaps in the depth of this research as the safety of this agent is not fully agreed upon. The Food and Drug Administration recently issued regulatory rules regarding TCS in some commercial products; however, it is still found in a variety of goods marketed as "antimicrobial" or "antibacterial". The purpose of this bibliometric study is to analyze research trends in this field and determine the amount of global attention TCS has received as to its relevancy in human health. Documenting and determining research concentration trends related to this field may outline where additional research is most necessary, as well as demonstrate the most valuable research produced and its relation to the advancement of our understanding of TCS. We found there to be a shift in research from TCS and its role in medical environments, to research based on the indirect effects of TCS through environmental contaminations, such as the propagation of antibiotic resistance. This shift was coupled with an increase in global research related to this field and identified China as a significant contributor. Although TCS has received notice, the simple fact of its continued use in so many common products, as well as the unclear understanding of its direct health impacts, reinforces the need for additional and more conclusive research before it has possible irreversible effects on our environment and health.

Antibacterial Capability of Air Filter Fiber Materials Treated with Triclosan against Indoor Environmental Microbes

Antibacterial filtration materials have been used effectively to control biological pollutants and purify indoor air. This study aimed to assess the antibacterial capability of three fiber filter materials treated with triclosan: glass fiber (GF), non-woven fabric (NF) and chemical fiber (CF). Triclosan was loaded onto the filtration materials by the impregnation method. The triclosan-treated filter materials exhibited antibacterial zones obviously: the average antibacterial bands against E. coli were 11.8 mm (GF), 13.3 mm (NF) and 10.5 mm (CF); against S. albus, they were 25.5 mm (GF), 21.0 mm (NF) and 23.5 mm (CF). The percent reductions of bacteria for the antibacterial air fiber materials treated with triclosan against E. coli were 71.4% (CF) and 62.6% (GF), while the percent reductions against S. albus were 61.3% (NF) and 84.6% (CF). These findings could help to reduce the transmission and threat of epidemic and purify the environment through the use of environmentally friendly antibacterial filter fibers.

Facile Synthesis of ZnO-CeO2 Heterojunction by Mixture Design and Its Application in Triclosan Degradation: Effect of Urea

In this study, simplex centroid mixture design was employed to determine the effect of urea on ZnO-CeO. The heterojunction materials were synthesized using a solid-state combustion method, and the physicochemical properties were evaluated using X-ray diffraction, nitrogen adsorption/desorption, and UV–Vis spectroscopy. Photocatalytic activity was determined by a triclosan degradation reaction under UV irradiation. According to the results, the crystal size of zinc oxide decreases in the presence of urea, whereas a reverse effect was observed for cerium oxide. A similar trend was observed for ternary samples, i.e., the higher the proportion of urea, the larger the crystallite cerium size. In brief, urea facilitated the co-existence of crystallites of CeO and ZnO. On the other hand, UV spectra indicate that urea shifts the absorption edge to a longer wavelength. Studies of the photocatalytic activity of TCS degradation show that the increase in the proportion of urea favorably influenced the percentage of mineralization.

Antibacterial Hydrogels Derived from Poly(γ-glutamic acid) Nanofibers

Biocompatible hydrogels with antibacterial properties derived from γ-polyglutamic acid (γ-PGA) were prepared from bulk and electrospun nanofibers. The antibacterial drugs loaded in these hydrogels were triclosan (TCS), chlorhexidine (CHX) and polyhexamethylene biguanide (PHMB); furthermore, bacteriophages were loaded as an alternative antibacterial agent. Continuous and regular γ-PGA nanofibers were successfully obtained by the electrospinning of trifluoroacetic acid solutions in a narrow polymer concentration range and restricted parameter values of flow rate, voltage and needle-collector distance. Hydrogels were successfully obtained by using cystamine as a crosslinking agent following previous published procedures. A closed pore structure was characteristic of bulk hydrogels, whereas an open but structurally consistent structure was found in the electrospun hydrogels. In this case, the morphology of the electrospun nanofibers was drastically modified after the crosslinking reaction, increasing their diameter and surface roughness according to the amount of the added crosslinker. The release of TCS, CHX, PHMB and bacteriophages was evaluated for the different samples, being results dependent on the hydrophobicity of the selected medium and the percentage of the added cystamine. A high efficiency of hydrogels to load bacteriophages and preserve their bactericide activity was demonstrated too.

Emerging nanomaterials for antibacterial textile fabrication

In recent times, the search for innovative material to fabricate smart textiles has been increasing to satisfy the expectation and needs of the consumers, as the textile material plays a key role in the evolution of human culture. Further, the textile materials provide an excellent environment for the microbes to grow, because of their large surface area and ability to retain moisture. In addition, the growth of harmful bacteria on the textile material not only damages them but also leads to intolerable foul odour and significant danger to public health. In particular, the pathogenic bacteria present in the fabric surface can cause severe skin infections such as skin allergy and irritation via direct human contact and even can lead to heart problems and pneumonia in certain cases. Recently, nanoparticles and nanomaterials play a significant role in textile industries for developing functional smart textiles with self-cleaning, UV-protection, insect repellent, waterproof, anti-static, flame-resistant and antimicrobial-resistant properties. Thus, this review is an overview of various textile fibres that favour bacterial growth and potential antibacterial nanoparticles that can inhibit the growth of bacteria on fabric surfaces. In addition, the probable antibacterial mechanism of nanoparticles and the significance of the fabric surface modification and fabric finishes in improving the long-term antibacterial efficacy of nanoparticle-coated fabrics were also discussed.

Topical Antiseptic Formulations for Skin and Soft Tissue Infections

Skin and soft tissue infections (SSTIs) are usually acute conditions of inflammatory microbial occupation of the skin layers and underlying soft tissues. SSTIs are one of the most frequent types of infection, typically requiring medical intervention and contribute to morbidity and mortality in both primary care and hospitalised patients. Due to the dramatic rise of antibiotic resistance, antiseptic agents can be potential alternatives for the prevention and treatment of SSTIs. Notably, they are commonly recommended in many global practical guidelines for use in per- and post- operative procedures. A range of antiseptics, including chlorhexidine, triclosan, alcohol, and povidone-iodine, are used and are mainly formulated as traditional, simple dosage forms such as solutions and semi-solids. However, in recent years, there have been studies reporting the potential for nanotechnology in the delivery of antiseptics. In this review, we have collated the scientific literature that focuses on topical antiseptic formulations for prevention and treatment of SSTIs, and have divided findings into traditional and advanced formulations. We conclude that although nanotechnological formulations have demonstrated potential advantages for delivering drugs; nevertheless, there is still scope for traditional formulations and further development of optimised topical formulations to address the rise of antimicrobial resistance.

Conductivity, Surface Tension, and Comparative Antibacterial Efficacy Study of Different Brands of Soaps of Nepal

The current study aims to evaluate the solution properties and antibacterial efficacy study of five different brands of toilet soaps of Nepal such as Okhati (OKT), Lifebuoy (LFBY), Lux (LX), Liril (LRL), and Chiuree Neem (NM). The evaluation of critical micelle concentration (CMC) and their thermodynamics and surface properties are also reported. This study was further extended to evaluate antibacterial efficacy against three pathogenic bacteria such as Staphylococcus aureus (S. aureus), Escherichia coli (E. coli), and Proteus vulgaris (P. vulgaris) by disc diffusion technique, and it was done at four different concentrations of soap. The bioactive ingredients present in them provide antibacterial potency to cure various skin problems caused by bacterial pathogens. Similarly, the antibacterial potency of LFBY was found higher than other soaps. Based on these studies, we can simply take LFBY soap at the highest rank in regards to antibacterial sensitivity.

Triclosan: antimicrobial mechanisms, antibiotics interactions, clinical applications, and human health

The large-scale applications of Triclosan in industrial and household products have created many health and environmental concerns. Despite the fears of its drug-resistance and other issues, Triclosan is still an effective drug against many infectious organisms. Knowing the cross-interactions of Triclosan with different antibiotics, bacteria, and humans can provide much-needed information for the risk assessment of this drug. We review the current understanding of the antimicrobial mechanisms of Triclosan, how microbes become resistant to Triclosan, and the synergistic and antagonistic effects of Triclosan with different antibiotics. Current literature on the clinical applications of Triclosan and its effect on fetus/child development are also summarized.

Antibacterial soap use impacts skin microbial communities in rural Madagascar

The skin harbors diverse communities of microorganisms, and alterations to these communities can impact the effectiveness of the skin as a barrier to infectious organisms or injury. As the global availability and adoption of antibacterial products increases, it is important to understand how these products affect skin microbial communities of people living in rural areas of developing countries, where risks of infection and injury often differ from urban populations in developed countries. We investigated the effect of antibacterial soap on skin microbial communities in a rural Malagasy population that practices subsistence agriculture in the absence of electricity and running water. We quantified the amount of soap used by each participant and obtained skin swab samples at three time points: prior to soap use, immediately after one week of soap use, and two weeks after soap use was discontinued. Soap use did not significantly impact ecological measures of diversity and richness (alpha diversity). However, the amount of soap used was a predictor of community-level change (beta diversity), with changes persisting for at least two weeks after subjects stopped using soap. Our results indicate that the overall species richness of skin microbial communities may be resistant to short-term use of antibacterial soap in settings characterized by regular contact with the natural environment, yet these communities may undergo shifts in microbial composition. Lifestyle changes associated with the use of antibacterial soap may therefore cause rapid alterations in skin microbial communities, with the potential for effects on skin health.

Antiseptic Agents Elicit Short-Term, Personalized, and Body Site-Specific Shifts in Resident Skin Bacterial Communities

Despite critical functions in cutaneous health and disease, it is unclear how resident skin microbial communities are altered by topical antimicrobial interventions commonly used in personal and clinical settings. Here we show that acute exposure to antiseptic treatments elicits rapid but short-term depletion of microbial community diversity and membership. Thirteen subjects were enrolled in a longitudinal treatment study to analyze the effects of topical treatments (i.e., ethanol, povidone-iodine, chlorhexidine, and water) on the skin microbiome at two skin sites of disparate microenvironment: forearm and back. Treatment effects were highly dependent on personalized and body site-specific colonization signatures, which concealed community dynamics at the population level when not accounted for in this analysis. The magnitude of disruption was influenced by the identity and abundance of particular bacterial inhabitants. Lowly abundant members of the skin microbiota were more likely to be displaced, and subsequently replaced, by the most abundant taxa prior to treatment. Members of the skin commensal family Propionibactericeae were particularly resilient to treatment, suggesting a distinct competitive advantage in the face of disturbance. These results provide insight into the stability and resilience of the skin microbiome, while establishing the impact of topical antiseptic treatment on skin bacterial dynamics and community ecology.

A unified framework for developing effective hygiene procedures for hands, environmental surfaces and laundry in healthcare, domestic, food handling and other settings

Hygiene procedures for hands, surfaces and fabrics are central to preventing spread of infection in settings including healthcare, food production, catering, agriculture, public settings, and home and everyday life. They are used in situations including hand hygiene, clinical procedures, decontamination of environmental surfaces, respiratory hygiene, food handling, laundry hygiene, toilet hygiene and so on. Although the principles are common to all, approaches currently used in different settings are inconsistent. A concern is the use of inconsistent terminology which is misleading, especially to people we need to communicate with such as the public or cleaning professionals. This paper reviews the data on current approaches, alongside new insights to developing hygiene procedures. Using this data, we propose a more scientifically-grounded framework for developing procedures that maximize protection against infection, based on consistent principles and terminology, and applicable across all settings. A key feature is use of test models which assess the state of surfaces after treatment rather than product performance alone. This allows procedures that rely on removal of microbes to be compared with those employing chemical or thermal inactivation. This makes it possible to ensure that a consistent "safety target level" is achieved regardless of the type of procedure used, and allows us deliver maximum health benefit whilst ensuring prudent usage of antimicrobial agents, detergents, water and energy.

Triclosan exposure, transformation, and human health effects

Triclosan (TCS) is an antimicrobial used so ubiquitously that 75% of the US population is likely exposed to this compound via consumer goods and personal care products. In September 2016, TCS was banned from soap products following the risk assessment by the US Food and Drug Administration (FDA). However, TCS still remains, at high concentrations, in other personal care products such as toothpaste, mouthwash, hand sanitizer, and surgical soaps. TCS is readily absorbed into human skin and oral mucosa and found in various human tissues and fluids. The aim of this review was to describe TCS exposure routes and levels as well as metabolism and transformation processes. The burgeoning literature on human health effects associated with TCS exposure, such as reproductive problems, was also summarized.

Possible underestimations of risks for the environment due to unregulated emissions of biocides from households to wastewater

The aim of this study was to investigate the role of household products as possible sources of biocidal active substances in municipal wastewater and their regulation under the Biocidal Products Regulation (EU) 528/2012. In 131 households, we investigated the prevalence of products used to control pests, washing and cleaning agents and select personal care products with high release to wastewater. Inventories of these products were established with the help of barcode scanning. All uses of biocidal active substances were evaluated regarding their assessment under the Biocidal Products Regulation. 2963 products were scanned in total, with 48% being washing and cleaning agents, 43% personal care products and 9% products used to control pests. Biocidal active substances were found in each household. These were observed primarily in washing and cleaning agents and personal care products (90%), while only a small percentage of the observations of biocidal active substances was in biocidal products. 64% of the observations of biocidal active substances were in applications that do not fall under the Biocidal Products Regulation and are thus not subject to its environmental risk assessment. This study shows clearly that risks for the environment are underestimated because unregulated emissions to wastewater occur. It demonstrates that there are gaps in the current chemical legislation that lead to a release of substances into wastewater that were not subject to environmental risk assessment under the Biocidal Products Regulation. This is one example of the limitations of scientific risk assessment of chemicals - its complexity is immense. From our point of view, the results underline the importance of a sustainable use of the substances as this is the only way to decrease yet unidentified risks.