Efficient degradation of benzalkonium chloride by FeMn-CA300 catalyst activated persulfate process: Surface hydroxyl potentiation mechanism and degradation pathway.

The consumption of disinfectants increased dramatically with the outbreak of the COVID-19 epidemic. Benzalkonium chloride (DDBAC), a cationic surfactant disinfectant for import and export cargoes, is used for effective degradation method. For DDBAC effective degradation, polyhedral Fe-Mn bimetallic catalyst of Prussian blue analogue (FeMn-CA300) was novelty developed for rapid peroxymonosulfate (PMS) activation. Results showed that the Fe/Mn redox and surface hydroxyl groups in the catalyst played an important role in the DDBAC-enhanced degradation. The removal effectiveness of 10 mg L-1 DDBAC was up to 99.4% in 80 min under the initial pH = 7, catalyst dosage of 0.4 g L-1, and PMS concentration of 15 mmol L-1. In addition, FeMn-CA300 had a wide pH applicability range. The results indicated that hydroxyls, sulfate radicals, and singlet oxygen could effectively improve the degradation efficiency, where sulfate radicals played a crucial role. Finally, the corresponding degradation path of DDBAC was further provided according to GC-MS results. The results of this study provide new insights into the degradation of DDBAC, thereby highlighting the great potential of FeMnca300/PMS to control refractory organic compounds in the aqueous phase.

HOCl as a Promising Candidate for Effective Containment of Covid 19 From Biological and Non-Biological Surfaces

Covid 19 is a pandemic disease spread almost in the whole world. To date, no medical advancement to curb the virus. Coronavirus is an enveloped virus transmitted from the biological and non-biological surface by direct or indirect contact. Limited literature revealed that the enveloped virus can be killed by disinfectants. There are many biocidal agents used for decontamination of the virus, yet they have many issues like toxicity, killing time, activation requirement, etc. Some are specific to the inanimate surface but not used by a human being. This current situation showed an urgent need for a biocidal agent which can act on biological as well as non-biological surfaces without any potential toxicity. Moreover, it should be easy to handle, inexpensive, and safe for the environment. Hypochlorous acid is a weak acid that acts as a powerful disinfectant and shows biocidal efficacy against a wide range of microorganisms. Hypochlorous acid is simple to use, inexpensive, eco-friendly, non-toxic, and stable. The properties of HOCl can be regulated at the site of preparation and therefore, its compliance is high. Hypochlorous acid seems to be a promising agent in disinfection and sterilization in healthcare facilities. Due to its diverse biocidal actions, it may be used as a potent disinfectant against novel coronavirus.Copyright © 2022 Bentham Science Publishers.

Toxicity of the disinfectant benzalkonium chloride (C14) towards cyanobacterium Microcystis results from its impact on the photosynthetic apparatus and cell metabolism

Quaternary ammonium compounds (QACs) are commonly used in a variety of consumer and commercial products, typically as a component of disinfectants. During the COVID-19 pandemic, QACs became one of the primary agents utilized to inactivate the SARS-CoV-2 virus on surfaces. However, the ecotoxicological effects of QACs upon aquatic organisms have not been fully assessed. In this study, we examined the effects of a widely used QAC (benzalkonium chloride-C14, BAC-14) on two toxigenic Microcystis strains and one non-toxigenic freshwater Microcystis strain and carried out an analysis focused on primary, adaptive and compensatory stress responses at apical (growth and photosynthesis) and metabolic levels. This analysis revealed that the two toxic Microcystis strains were more tolerant than the non-toxic strain, with 96 hr-EC50 values of 0.70, 0.76, and 0.38 mg/L BAC-14 for toxigenic M. aeruginosa FACHB-905, toxigenic M. aeruginosa FACHB-469, and non-toxigenic M. wesenbergii FACHB-908, respectively. The photosynthetic activities of the Microcystis, assessed via Fv/Fm values, were significantly suppressed under 0.4 mg/L BAC-14. Furthermore, this analysis revealed that BAC-14 altered 14, 12, and 8 metabolic pathways in M. aeruginosa FACHB-905, M. aeruginosa FACHB-469, and M. wesenbergii FACHB-908, respectively. It is noteworthy that BAC-14 enhanced the level of extracellular microcystin production in the toxigenic Microcystis strains, although cell growth was not significantly affected. Collectively, these data show that BAC-14 disrupted the physiological and metabolic status of Microcystis cells and stimulated the production and release of microcystin, which could result in damage to aquatic systems. © 2022

Electrochemical oxidation of the increasingly used disinfectant benzalkonium chloride

Benzalkonium chloride (BAC) is a key ingredient in many cleaning and disinfectant products due to it being an effective antiviral and biocidal agent. Because of its prolific use, especially following the recent global COVID pandemic, increased levels of BAC have been found in the environment, in particular, in wastewater, where it has negative impacts due to its toxicity. This necessitates an effective treatment for BAC in wastewater to reduce its toxicity. In this work, electrochemical oxidation of BAC on a boron-doped diamond anode was studied to successfully remove BAC. The electrochemical measurements performed at different current densities confirmed that BAC was completely oxidized within 20 min of treatment at 50 mA/cm2. However, chemical oxygen demand (COD) measurements showed that around 50% of the initial BAC was completely mineralized after 1 h of degradation at 50 mA/cm2, while the remaining electrooxidation of BAC resulted in the production of transformation products. © 2023 Canadian Society for Chemical Engineering.

Surfactant-Impregnated MOF-Coated Fabric for Antimicrobial Applications.

Since the onset of the SARS-CoV-2 pandemic, the world has witnessed over 617 million confirmed cases and more than 6.54 million confirmed deaths, but the actual totals are likely much higher. The virus has mutated at a significantly faster rate than initially projected, and positive cases continue to surge with the emergence of ever more transmissible variants. According to the CDC, and at the time of this manuscript submission, more than 77% of all current US cases are a result of the B.5 (omicron). The continued emergence of highly transmissible variants makes clear the need for more effective methods of mitigating disease spread. Herein, we have developed an antimicrobial fabric capable of destroying a myriad of microbes including betacoronaviruses. We have demonstrated the capability of this highly porous and nontoxic metal organic framework (MOF), γ-CD-MOF-1, to serve as a host for varied-length benzalkonium chlorides (BACs; active ingredient in Lysol). Molecular docking simulations predicted a binding affinity of up to -4.12 kcal·mol-1, which is comparable to that of other reported guest molecules for this MOF. Similar Raman spectra and powder X-ray diffraction patterns between the unloaded and loaded MOFs, accompanied by a decrease in the Brunauer-Emmett-Teller surface area from 616.20 and 155.55 m2 g-1 respectively, corroborate the suggested potential for pore occupation with BAC. The MOF was grown on polypropylene fabric, exposed to a BAC-loading bath, washed to remove excess BAC from the external surface, and evaluated for its microbicidal activity against various bacterial and viral classes. Significant antimicrobial character was observed against Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli, bacteriophage, and betacoronavirus. This study shows that a common mask material (polypropylene) can be coated with BAC-loaded γ-CD-MOF-1 while maintaining the guest molecule's antimicrobial effects.

Preservation of Personal Care and Cosmetic Products: Effectiveness and Safety During the COVID-19 Pandemic

The global beauty industry has been shocked by the COVID-19 pandemic. Currently, with increased hygiene habits, the choice of preservatives can be impacted by consumers opting for safe products. Products without preservation system could quickly become contaminated with mold, fungi, and bacteria, resulting in spoilage and increased risk of infection. This review explores the possible impacts of COVID-19 in the preservation of cosmetics from the perspective of effectiveness and safety. The preservatives included benzalkonium chloride, propylparaben, butylparaben, phenoxyethanol, sorbic acid, potassium sorbate, as well as the multifunctional/booster agents ethylhexylglycerin, caprylyl glycol, and natural antimicrobials. First, we highlight the current scenario of cosmetic preservation, the mode of action, and the maximum concentration allowed for preservatives;then examines overexposure to preservatives. Unexpectedly, the COVID-19 pandemic paralyzed the world market, and cosmetic industries had to adapt to a new reality. Due to the widespread use of cosmetic products, the prevalence of allergies, microbiological resistance, the need for proper prevention of product contamination, and concerns over the safety of preservatives, further investigations into the modes of action of traditional or alternative preservatives are needed to create successful safety products.

Capsanthin from Capsicum annum fruits exerts anti-glaucoma, antioxidant, anti-inflammatory activity, and corneal pro-inflammatory cytokine gene expression in a benzalkonium chloride-induced rat dry eye model.

Dry eye disease (DED) is a complex ocular surface inflammatory disease. Its occurrence varies widely over the world, ranging from 5% to 34%. The use of preservatives, specifically benzalkonium chloride, in the ocular drops worsens the DED conditions. Furthermore, the Covid-19 pandemic increased screen time and the use of face masks and shields. As a result, the number of people suffering from dry eye disease (DED) has increased significantly in recent years. The main objective of our study is to find a solution to manage the dry eye disease (DED) preferably from natural source without any adverse events. In this study, the beneficial effects of capsanthin from Capsicum annum (CCA) were evaluated on benzalkonium chloride (BAC)-induced dry eye disease (DED) in Albino Wistar rats. Oral supplementation of CCA resulted in a statistically significant decrease in intraocular pressure (IOP) (p < .0001), increase in tear break-up time (TBUT) (p < .01), decline in Schirmer test results (p < .01), and decrease in corneal surface inflammation (p < .01). Capsanthin ameliorated in reducing oxidative stress by increasing serum antioxidant levels such as glutathione peroxidase (GPX), nitric oxide (NO), and lactoferrin (LTF) and inhibiting matrix metalloproteinases 2 and 9 (MMP2 and MMP9) (p < .0001). Capsanthin treatment significantly inhibited the expression of inflammatory cytokines, tumor necrosis factor-alpha (TNF-α), interleukins (IL-2, IL-4, IL-6), and pro-inflammatory mediator, matrix metalloproteinase-9 (MMP9). Furthermore, the lacrimal gland expressed vascular cell adhesion molecule (VCAM-1), and prostaglandin-endoperoxide synthase 2 (PTGS2) was suppressed by CCA treatment. PRACTICAL APPLICATIONS: Benzalkonium chloride (BAC), a preservative widely used in the topical ocular drug delivery system (ODDS), causes undesirable effects such as dry eye disease as well as ameliorating intraocular pressure leading to optical nerve damage and irreversible vision loss. Capsanthin from Capsicum annum (CCA) can be used to treat symptoms related to dry eye disease such as inflammation, eye irritation, visual disturbance, ocular discomfort with potential damage to the ocular surface. The CCA may be beneficial in the treatment of glaucoma, an elevated intraocular pressure. Capsanthin from C. annum can be useful in managing DED by increasing tear break-up time (TBUT), declining in Schirmer test results and decreasing in corneal surface inflammation.

In vitro neurotoxicity evaluation of biocidal disinfectants in a human neuron-astrocyte co-culture model.

Biocidal disinfectants (BDs) that kill microorganisms or pathogens are widely used in hospitals and other healthcare fields. Recently, the use of BDs has rapidly increased as personal hygiene has become more apparent owing to the pandemic, namely the coronavirus outbreak. Despite frequent exposure to BDs, toxicity data of their potential neurotoxicity (NT) are lacking. In this study, a human-derived SH-SY5Y/astrocyte was used as a co-culture model to evaluate the chemical effects of BDs. Automated high-content screening was used to evaluate the potential NT of BDs through neurite growth analysis. A set of 12 BD substances classified from previous reports were tested. Our study confirms the potential NT of benzalkonium chloride (BKC) and provides the first evidence of the potential NT of poly(hexamethylenebicyanoguanide-hexamethylenediamine) hydrochloride (PHMB). BKC and PHMB showed significant NT at concentrations without cytotoxicity. This test system for analyzing the potential NT of BDs may be useful in early screening studies for NT prior to starting in vivo studies.

A Propidium Monoazide (PMAxx)-Droplet Digital PCR (ddPCR) for the Detection of Viable Burkholderia cepacia Complex in Nuclease-Free Water and Antiseptics

Pharmaceutical products contaminated with Burkholderia cepacia complex (BCC) strains constitute a serious health issue for susceptible individuals. New detection methods to distinguish DNA from viable cells are required to ensure pharmaceutical product quality and safety. In this study, we have assessed a droplet digital PCR (ddPCR) with a variant propidium monoazide (PMAxx) for selective detection of live/dead BCC cells in autoclaved nuclease-free water after 365 days, in 0.001% chlorhexidine gluconate (CHX), and in 0.005% benzalkonium chloride (BZK) solutions after 184 days. Using 10 μM PMAxx and 5 min light exposure, a proportion of dead BCC was quantified by ddPCR. The detection limit of culture-based method was 104 CFU/mL, equivalent to 9.7 pg/μL for B. cenocepacia J2315, while that of ddPCR was 9.7 fg/μL. The true positive rate from nuclease-free water and CHX using PMAxx-ddPCR assay was 60.0% and 38.3%, respectively, compared to 85.0% and 74.6% without PMAxx (p < 0.05), respectively. However, in BZK-treated cells, no difference in the detection rate was observed between the ddPCR assay on samples treated with PMAxx (67.1%) and without PMAxx (63.3%). This study shows that the PMAxx-ddPCR assay provides a better tool for selective detection of live BCC cells in non-sterile pharmaceutical products.

Inactivation of SARS-CoV-2 by 2 commercially available Benzalkonium chloride-based hand sanitizers in comparison with an 80% ethanol-based hand sanitizer.

BACKGROUND: The CDC and WHO recommend alcohol-based hand sanitizers to inactivate severe acute respiratory syndrome coronavirus-2 [SARS-CoV-2]. AIM: Benzalkonium chloride [BAK] is another hand sanitizer active ingredient that could be used in response to the global pandemic. Deployment of BAK-based hand sanitizers could reduce shortages of alcohol products and increase hand hygiene options where there are social, physical, and toxicological constraints on alcohol use. METHODS: Two commercially available BAK-based hand sanitizers, a concentrate diluted on-site with water and a ready-to-use product, were tested for activity against SARS-CoV-2 in the European Norm Virucidal Activity Suspension Test [EN14476]. A WHO and CDC-recommended 80% alcohol-based hand sanitizer formulation was tested in parallel. FINDINGS: Both BAK formulations demonstrated a ≥4.0 log10 reduction of SARS-CoV-2 in 30 seconds, meeting the EN14476 performance standard for virucidal activity against SARS-CoV-2 and matching the in vitro effectiveness of the ethanol-based sanitizer. CONCLUSION: These findings indicate that a commercial BAK hand hygiene formulation may be another effective means of inactivating the SARS-CoV-2 virus and could be considered as option for pandemic response.

Mouthrinses against SARS-CoV-2 - High antiviral effectivity by membrane disruption in vitro translates to mild effects in a randomized placebo-controlled clinical trial.

The emergence of the Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) represents an unprecedented threat for the human population, necessitating rapid and effective intervention measures. Given the main infection route by airborne transmission, significant attention has been bestowed upon the use of antiseptic mouthrinses as a way to possibly reduce infectious viral titers. However, clinical evaluations are still sparse. Thus, we evaluated a wide variety of antiseptic agents that can be used as mouthrinses for their antiviral effects in vitro and their respective mode of action. One of the most promising antiseptic agents (benzalkoniumchloride, BAC) was used in a randomized placebo-controlled clinical trial with subsequent analysis of viral loads by RT-qPCR and virus rescue in cell culture. Mechanistic analysis revealed that treatment with BAC and other antiseptic agents efficiently inactivated SARS-CoV-2 in vitro by primarily disrupting the viral envelope, without affecting viral RNA integrity. However, the clinical application only resulted in a mild reduction of viral loads in the oral cavity. These results indicate that gargling with mouthrinses comprising single antiseptic agents may play a minor role towards a potential reduction of transmission rates and thus, these findings are of utmost importance when considering alternative COVID-19 prevention strategies.

Antiseptic Materials on the Base of Polymer Interpenetrating Networks Microgels and Benzalkonium Chloride.

Polymer microgels, including those based on interpenetrating networks (IPNs), are currently vastly studied, and their practical applications are a matter of thriving research. In this work, we show the perspective for the use of polyelectrolyte IPN microgels either as scavengers or carriers of antiseptic substances. Here, we report that poly-N-isopropylacrylamide/polyacrylic acid IPN microgels can efficiently absorb the common bactericidal and virucidal compound benzalkonium chloride. The particles can form a stable aqueous colloidal suspension or be used as building blocks for soft free-standing films. Both materials showed antiseptic efficacy on the examples of Bacillus subtilis and S. aureus, which was approximately equal to the commercial antibiotic. Such polymer biocides can be used as liquid disinfectants, stable surface coatings, or parts of biomedical devices and can enhance the versatility of the possible practical applications of polymer microgels.

Pronounced temporal changes in soil microbial community and nitrogen transformation caused by benzalkonium chloride.

As one typical cationic disinfectant, quaternary ammonium compounds (QACs) were approved for surface disinfection in the coronavirus disease 2019 pandemic and then unintentionally or intentionally released into the surrounding environment. Concerningly, it is still unclear how the soil microbial community succession happens and the nitrogen (N) cycling processes alter when exposed to QACs. In this study, one common QAC (benzalkonium chloride (BAC) was selected as the target contaminant, and its effects on the temporal changes in soil microbial community structure and nitrogen transformation processes were determined by qPCR and 16S rRNA sequencing-based methods. The results showed that the aerobic microbial degradation of BAC in the two different soils followed first-order kinetics with a half-life (4.92 vs. 17.33 days) highly dependent on the properties of the soil. BAC activated the abundance of N fixation gene (nifH) and nitrification genes (AOA and AOB) in the soil and inhibited that of denitrification gene (narG). BAC exposure resulted in the decrease of the alpha diversity of soil microbial community and the enrichment of Crenarchaeota and Proteobacteria. This study demonstrates that BAC degradation is accompanied by changes in soil microbial community structure and N transformation capacity.

56th Congress of Veterinary Epidemiology

This proceedings contains 10 papers on risk management policy of the ministry of health, labour and welfare for ensuring safe wild game meat, prospective of application of food safety risk assessment for game meat, coronavirus disease (COVID-19) for animal owners, shelter medicine and COVID-19, the characteristics of bats as natural reservoirs of the novel coronavirus, chalkbrood in honey bees and its control measures, the economic impact of classical swine fever in Japan, benzalkonium chloride resistance in Listeria monocytogenes isolated in Japan, COVID-19 outbreak and epidemiological research in Japan and the amendment of the act on domestic animal infectious diseases control.

Molecular mechanism of antibiotic resistance induced by mono- and twin-chained quaternary ammonium compounds.

The usage of quaternary ammonium compounds (QACs) as disinfectants has increased dramatically since the outbreak of COVID-19 pandemic, leading to potentially accelerated emergence of antibiotic resistance. Long-term exposure to subinhibitory level QACs can lead to multidrug resistance, but the contribution of mutagenesis to resistance evolution is obscure. In this study, we subcultured E. coli K-12 under subinhibitory (0.25 × and 0.5 × Minimum Inhibitory Concentration, MIC) or inhibitory (1 × and 2 × MIC) concentrations of benzalkonium chloride (BAC, mono-chained) or didecyldimethylammonium chloride (DDAC, twin-chained) for 60 days. The sensitivity of QAC-adapted cells to five typical antibiotics decreased significantly, and in particular, the MIC of rifampicin increased by 85 times. E. coli adapted faster to BAC but developed 20-167% higher antibiotic resistance with 56% more mutations under DDAC exposure. The broader mutations induced by QACs, including negative regulators (acrR, marR, soxR, and crp), outer membrane proteins and transporters (mipA and sbmA), and RNA polymerase (rpoB and rpoC), potentially contributed to the high multi-drug resistance. After QACs stresses were removed, the phenotypic resistance induced by subinhibitory concentrations of QACs was reversible, whereas that induced by inhibitory concentrations of QACs was irreversible. The different patterns and molecular mechanism of antibiotic resistance induced by BAC and DDAC is informative to estimating the risks of broader QACs present at varied concentrations in the environment.

The renaissance of barrier contraception (based on the data from an international clinical trial)

Background. In recent years, interest in the use of barrier methods of contraception has increased, since many women prefer them in connection with the change in the epidemiological situation associated with COVID-19, with contraindications to other methods of contraception, as well as with irregular sex life and casual sexual intercourse. In addition, these methods of contraception are preferred for breastfeeding mothers and pre- and postmenopausal women. Studies of the efficacy of spermicidal agents in late reproductive age women have not previously been carried out, although their use in this population is of particular interest, since these agents do not have a systemic effect and, if used correctly, can prevent unwanted pregnancies. The article presents data from an international French-Russian study of the efficacy of spermicides containing benzalkonium chloride in late reproductive age women (over 40 years). The study was carried out on the basis of 7 private offices of obstetricians and gynecologists in France and 6 obstetric and gynecological clinics in Russia. Aim. Assessment of the contraceptive efficacy, safety and acceptability of a cream containing benzalkonium chloride in women over 40 years of age. Materials and methods. The study included non-pregnant women aged 40 and over who had at least 1 menstrual period in the past 3 months and who would like to use spermicides as contraception for at least 6 months. After a 6-month period of mandatory use of spermicide, patients could, if desired, continue to use it for the next 6 months. All women were given Pharmatex (1.2%), a vaginal cream containing benzalkonium chloride (1.2 g per 100 g of cream) as the active ingredient, 1 standard dose before each intercourse. The primary endpoint was the Pearl Index. The acceptability of the method after each use of the cream, the moisturizing effect, and the woman's and researcher's overall satisfaction with this method of contraception were also assessed. Safety was assessed using adverse event monitoring. Results. An analysis of efficacy of the study drug showed that during study, pregnancy did not occur in any of the women. Pearl Index for 12 months was 0. Over the mandatory 6-month period, the use of Pharmatex cream was assessed by patients as acceptable (to some extent acceptable, acceptable, completely acceptable) in 98% of sexual intercourse, and over the 12-month period - in 98.6% of intercourse. The moisturizing effect of the cream was noted by 96.1% of women. In 6 months of the use of Pharmatex cream, overall satisfaction was rated as quite good, good, or very good by 99.3% of patients and in 12 months - by 100% of patients. Adverse events were noted only in 0.5% of cases. Most of these events were assessed as unrelated to the study drug. Conclusion. The use of a benzalkonium chloride spermicidal cream can be considered an effective and acceptable method of contraception for women over the age of 40. It is well tolerated, has a moisturizing effect on the vaginal mucosa, and meets the needs and lifestyle of women. The contraceptive with benzalkonium chloride has a favorable safety profile: it does not adversely affect the normal flora of the vagina, can be used during breastfeeding, since it does not penetrate into the vascular bed and doesn't have systemic effects. © 2021 Consilium Medikum. All Rights Reserved.

Altered toxicological endpoints in humans from common quaternary ammonium compound disinfectant exposure.

Humans are frequently exposed to Quaternary Ammonium Compounds (QACs). QACs are ubiquitously used in medical settings, restaurants, and homes as cleaners and disinfectants. Despite their prevalence, nothing is known about the health effects associated with chronic low-level exposure. Chronic QAC toxicity, only recently identified in mice, resulted in developmental, reproductive, and immune dysfunction. Cell based studies indicate increased inflammation, decreased mitochondrial function, and disruption of cholesterol synthesis. If these findings translate to human toxicity, multiple physiological processes could be affected. This study tested whether QAC concentrations could be detected in the blood of 43 human volunteers, and whether QAC concentrations influenced markers of inflammation, mitochondrial function, and cholesterol synthesis. QAC concentrations were detected in 80 % of study participants. Blood QACs were associated with increase in inflammatory cytokines, decreased mitochondrial function, and disruption of cholesterol homeostasis in a dose dependent manner. This is the first study to measure QACs in human blood, and also the first to demonstrate statistically significant relationships between blood QAC and meaningful health related biomarkers. Additionally, the results are timely in light of the increased QAC disinfectant exposure occurring due to the SARS-CoV-2 pandemic. MAIN FINDINGS: This study found that 80 % of study participants contained QACs in their blood; and that markers of inflammation, mitochondrial function, and sterol homeostasis varied with blood QAC concentration.

Antimicrobial Face Shield: Next Generation of Facial Protective Equipment against SARS-CoV-2 and Multidrug-Resistant Bacteria.

Transparent materials used for facial protection equipment provide protection against microbial infections caused by viruses and bacteria, including multidrug-resistant strains. However, transparent materials used for this type of application are made of materials that do not possess antimicrobial activity. They just avoid direct contact between the person and the biological agent. Therefore, healthy people can become infected through contact of the contaminated material surfaces and this equipment constitute an increasing source of infectious biological waste. Furthermore, infected people can transmit microbial infections easily because the protective equipment do not inactivate the microbial load generated while breathing, sneezing or coughing. In this regard, the goal of this work consisted of fabricating a transparent face shield with intrinsic antimicrobial activity that could provide extra-protection against infectious agents and reduce the generation of infectious waste. Thus, a single-use transparent antimicrobial face shield composed of polyethylene terephthalate and an antimicrobial coating of benzalkonium chloride has been developed for the next generation of facial protective equipment. The antimicrobial coating was analyzed by atomic force microscopy and field emission scanning electron microscopy with elemental analysis. This is the first facial transparent protective material capable of inactivating enveloped viruses such as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in less than one minute of contact, and the methicillin-resistant Staphylococcus aureus and Staphylococcus epidermidis. Bacterial infections contribute to severe pneumonia associated with the SARS-CoV-2 infection, and their resistance to antibiotics is increasing. Our extra protective broad-spectrum antimicrobial composite material could also be applied for the fabrication of other facial protective tools such as such as goggles, helmets, plastic masks and space separation screens used for counters or vehicles. This low-cost technology would be very useful to combat the current pandemic and protect health care workers from multidrug-resistant infections in developed and underdeveloped countries.

Systemic absorption of benzalkonium chloride after maximal use of a consumer antiseptic wash product.

An in vivo pharmacokinetic study was conducted using consumer antiseptic wash containing 0.13% benzalkonium chloride (BAC) to assess the effect of dermal absorption on long-term systemic exposure to BAC. The objective of the study was to determine blood levels of BAC under maximal use conditions. Subjects were enlisted to wash their hands 60 s with soap containing 0.13% BAC 30 times per day over an 8-9 h time period for 5 consecutive days. The test product with the highest absorption potential was selected based on market share and results from in vitro permeation testing. Blood plasma was collected from subjects on 32 occasions over the 6-day study period. Plasma samples were analyzed for the C12 and C14 homologs of BAC using LC-MS/MS with a lower limit of quantitation (LLOQ) of 106.9 and 32.6 ng/L, respectively. For the 32 subjects, C12 homolog was detected above the LLOQ in only four of 1,024 plasma samples at 117.8-191.7 ng/L, and C14 homolog was detected in only one sample at 59.5 ng/L. Consequently, systemic exposure to BAC in antimicrobial soap is very low and below the level of concern identified by the U.S. Food and Drug Administration (500 ng/L) even under maximal use conditions.