Comprehensive risk assessment of the inhalation of plasticizers from the use of face masks.

Disposable masks, formed mainly from polymers, often incorporate various chemical additives to enhance their performance. These additives, which include plasticizers, may be released during mask usage, presenting a novel source of human exposure to these compounds. In this study, the presence of 16 organophosphate esters (OPEs), 11 phthalates, and four alternative plasticizers, in four various types of face masks, were studied, as well as their release during simulated mask use (artificial laboratory conditions). Total plasticizer concentrations exhibited minimal variation across different mask types, with mean values of 7.27 µg/face mask for surgical, 8.61 µg/face mask for reusable, 11.0 µg/face mask for KN-95, and 13.9 µg/face mask for FFP2 masks. To explore plasticizer release behavior, inhalation experiments were conducted under different conditions. The findings revealed a significant temperature-dependent enhancement in plasticizer release from masks, subsequently increasing human inhalation exposure. The inhalation experiments showed variation in the release percentages, ranging from 0.1 to 95 %, depending on the specific compound and mask type. Notably, OPEs exhibited a mean release percentage of 1.0 %, similar to phthalates, which showed a 1.2 % release. Although alternative plasticizers were less frequently released, they still presented a notable percentage of release of 4.1 %. Daily intake estimations via inhalation ranged from 0.01 to 9.04 ng/kg body weight (bw)/day for these additives. Using these estimations, carcinogenic and non-carcinogenic risks associated with this exposure to these compounds were evaluated. All calculated values for the specific compounds studied in this paper remained below the established threshold limits. However, they do represent an additional exposure pathway that, when considered alongside other more predominant routes such as indoor/outdoor inhalation, dermal absorption, and dietary intake, makes the total exposure worthy of consideration.

Interfaces for Home Noninvasive Ventilation.

The choice of interface used to deliver noninvasive ventilation (NIV) is a critical element in successfully and safely establishing home NIV in people with sleep hypoventilation syndromes. Both patient-related and equipment-related factors need to be considered when selecting an interface. Recognizing specific issues that can occur with a particular style of mask is important when troubleshooting NIV problems and attempting to minimize side effects. Access to a range of mask styles and designs to use on a rotational basis is especially important for patients using NIV on a more continuous basis, those at risk of developing pressure areas, and children.

Energy usage of spruce with waste face masks and spent coffee grounds as fuel in a pellet boiler.

It is necessary to reduce dependency on fossil fuels for heating and waste generation, while also utilizing the energy potential of waste materials. One possibility is to create fuel pellets where waste makes up a small proportion so that the properties of the wood are not significantly altered with. This article investigates the energy usage of pellets containing spent coffee grounds (5 % or 10 %) and waste face masks (5 % or 10 %), with spruce sawdust as the primary input material (80 % or 90 %). The elemental, thermogravimetric, calorific value, mechanical durability, emission and performance characteristics, and ash melting temperatures of the pellets were evaluated during the experiment. The results were compared with respect to pure spruce sawdust pellets and the specified limit values for wood pellets in commercial and residential applications as specified in ISO 17225 [18]. Both tested samples met the element content limit (N, S, Cl, As, Cd, Cr, Cu, Pb, Hg, Ni, and Zn) for the highest quality grade (A1). No significant amounts of harmful elements were detected. The samples also complied with the limits of moisture content, ash content, and net calorific value (also known as lower calorific value). All samples met the emission limits in their respective classes (3, 4, or 5) according to STN EN 303-5+A1 [35]. However, the samples failed to meet the limit values for mechanical durability and ash melting temperatures. Despite this, the manufactured pellet samples represent a suitable fuel product for combustion purposes as a more sustainable thermal energy fuel.

Adsorption characteristics and mechanisms of bisphenol A on novel nitrogen-modified biochar derived from waste masks and biomass.

Resource utilization of waste masks has become an urgent scientific issue. In this work, with sustainably, waste masks and biomass were co-pyrolysis with oxygen limitation to prepare mask-based biochar (MB). Then, urea was introduced to prepare novel nitrogen modified mask-based biochar (NMB) via a one-step hydrothermal synthesis method. The adsorption characteristics of NMB on the emerging environmental pollutant, bisphenol A (BPA), were evaluated via batch adsorption tests. Moreover, the physicochemical properties of the materials were characterized with various advanced techniques. Also, the roles of waste masks and nitrogen modification were explored. The adsorption mechanisms of NMB on BPA were revealed as well as the performance differences between different adsorbents. The results showed that waste masks participated in thermochemical reactions, shaped the microsphere structure of biochar, and increased the types of surface functional groups. The nitrogen modification enriched the surface elemental composition and activated the specific surface area via the mesopore. These would enhance the adsorption performance. The maximum adsorption of BPA by NMB was 62.63 mg·g-1, which was approximately 2.35-5.58 times higher than that of the control materials. Temkin model and pseudo-second-order model optimally simulate the isothermal and kinetic adsorption, respectively. The adsorption mechanisms are jointly by physical and chemical adsorption, which mainly includes π-π interaction, hydrogen bonding, intraparticle diffusion, surface adsorption, and ion exchange. After discussion and evaluation, NMB has lower preparation process cost (7.21 USD·kg-1) and safety, with potential for environmental applications. This study aims to expand new ideas for the comprehensive utilization of waste masks and the preparation of eco-friendly materials. Moreover, it provides a theoretical basis for the removal of BPA.

COVID-19: did the masks work?

During the early stages of the COVID-19 pandemic, we called for mandatory public masking to 'flatten the curve'. We helped formulate a national standard (SWiFT 19) for barrier facemasks, and, using a novel laser-based approach, we determined that mask efficacy is dependent on both fabric and fit; with both variables being inversely related. Herein, we take a retrospective view of the role of masks during the pandemic and surmise that, on the balance of evidence to date, masks were effective at stemming the spread of SARS-CoV-2 and may well be an effective early control strategy for potential future respiratory pandemics.

Face coverings, which cover the nose and mouth, are a means of preventing infections that travel in the air. These include viruses such as SARS-CoV-2, which causes COVID-19. Face coverings, or masks, played a key role during the COVID-19 pandemic by reducing person-to-person spread of the virus. The key features of a mask that make it effective are the material from which it is made and how closely the mask fits the face. A loosely fitting mask, for example, will lead to gaps around the nose and cheeks through which droplets can escape. A better fitting mask will have less leakage. Masks made from light single-layer material is less able to prevent droplet penetration than thicker, multi-layered fabric. Properly fashioned and fitted face masks are an effective means of slowing the spread of infections that travel in the air.

Masks As a New Hotspot for Antibiotic Resistance Gene Spread: Reveal the Contribution of Atmospheric Pollutants and Potential Risks.

The consumption of disposable surgical masks (DSMs) considerably increased during the coronavirus pandemic in 2019. Herein, we explored the spread of antibiotic resistance genes (ARGs) and the potential risks of antibiotic resistant bacteria (ARB) on DSMs. At environmentally relevant concentrations, the conjugate transfer frequency (CTF) of ARGs increased by 1.34-2.37 folds by 20 µg/m3 of atmospheric water-soluble inorganic ions (WSIIs), and it increased by 2.62-2.86 folds by 80 ng/m3 of polycyclic aromatic hydrocarbons (PAHs). Total suspended particulates (TSP) further promoted the CTF in combination with WSIIs or PAHs. Under WSII and PAH exposure, gene expression levels related to oxidative stress, cell membrane, and the adenosine triphosphate (ATP) were upregulated. WSIIs predominantly induced cellular contact, while PAHs triggered ATP formation and membrane damage. Molecular dynamics simulations showed that WSIIs and PAHs reduced membrane lipid fluidity and increased membrane permeability through interactions with the phosphatidylcholine bilayer. DSM filtering performance decreased, and the CTF of ARGs increased with the wearing time. The gut simulator test showed that ARB disrupted the human gut microbial community and increased total ARG abundance but did not change the ARG abundance carried by ARB themselves. A mathematical model showed that long-term WSII and PAH exposure accelerated ARG dissemination in DSMs.

COVID-19 Impact on Refugees Mask-Wearing Behaviors and Intentions.

COVID-19 challenged countries in addressing population and raising awareness about mask-wearing during pandemic; Lebanon is a refugee hotspot, with humanitarian responsibility for their protection. The goal of this study is to emphasize the need of raising awareness among vulnerable populations and studying their mask-wearing behavior and intentions. This research draws on findings from a survey characterized by refugees' representatives from NGO, focusing on the behaviors and implications of refugees' mask-wearing. To address the study question, a customized survey based on Theory of Interpersonal Behavior was undertaken, in which the behavior of refugees was impacted by their desire to engage in an activity. The findings show that refugees are influenced by other people's mask-wearing behavior; they view masks as providing protection and aim to use them in the future provided all enabling conditions are met. Artificial intelligence might be a better monitor for this behavior in the future.

Efficacy of powered air-purifying respirators (PAPRs) for source control of simulated respiratory aerosols.

BACKGROUND: Loose-fitting powered air-purifying respirators (PAPRs) are a popular alternative to the use of filtering facepiece respirators for health care workers. Although PAPRs protect the wearer from aerosol particles, their ability to block infectious aerosol particles exhaled by the wearer from being released into the environment (called source control) is unclear. METHODS: The source control performance of 4 PAPRs with loose-fitting facepieces were tested using a manikin that exhales aerosol particles. The PAPRs were tested by themselves and in combination with a face-worn product intended to provide source control (either a surgical mask or an N95 filtering facepiece respirator). RESULTS: Two PAPR facepieces with filtration panels significantly reduced the release of exhaled aerosols into the environment, while 3 facepieces without such panels did not. Wearing a surgical mask or respirator under the facepiece significantly improved the source control performance. CONCLUSIONS: Most PAPR facepieces do not block aerosols exhaled by the wearer. Facepieces designed to filter exhaled particles can prevent aerosols from being released into the environment. Wearing a surgical mask or a filtering facepiece respirator under the facepiece can also provide source control, but PAPRs are not typically certified for use with masks and respirators.

Hazardous effects of plastic microfibres from facial masks to aquatic animal health: Insights from zebrafish model.

Facial masks are a source of plastic microfibres (PMFs) in the aquatic environment, an emerging risk factor for aquatic organisms. However, little is known concerning its impact during the early developmental stages of fish. Thus, the current study aimed to evaluate the potential interaction and developmental toxicity of PMFs derived from leachate of surgical masks (SC-Msk) and N-95 facial masks (N95-Msk) using a multi-biomarker approach in developing zebrafish (Danio rerio). PMFs from both facial masks were obtained and characterized by multiple techniques. Zebrafish embryos were exposed to environmentally relevant concentrations of PMFs from both facial masks (1000, 10,000, and 100,000 particle L-1), and the toxicity was analysed in terms of mortality, hatching rate, neurotoxicity, cardiotoxicity, morphological changes, reactive oxygen species (ROS) levels, cell viability, and behavioural impairments. The results showed that both facial masks can release PMFs, but the N95-Msk produced a higher concentration of PMFs than SC-Msk. Both PMFs can interact with zebrafish chorion and don't cause effects on embryo mortality and hatching; however, zebrafish embryos showed cardiotoxic effects, and larvae showed increased agitation, average speed, and distance travelled, indicating the behavioural impairments induced by PMFs derived from facial masks. Overall, results showed the risk of PMFs to the health of freshwater fish, indicating the need for greater attention to the disposal and ecotoxicological effects of facial masks on aquatic organisms.

Electrospun nonwoven fabric of poly(ε-caprolactone)/n-phosphonium chitosan for antiviral applications: Fabrication, characterization, and potential efficacy.

This work reports the virucidal properties of nonwoven fibers developed via electrospinning with polycaprolactone (PCL) and chitosan quaternized with phosphonium salt (NPCS), emphasizing the influence of NPCS concentration on the structure of fibers and their performance against the MHV-3 coronavirus. The addition of NPCS enhances solutions conductivity and viscosity, leading to fibers containing a finer porous structure with a more hydrophilic and smoother surface, thereby making them a potent barrier against respiratory particles, which is a key factor for protective face masks. In terms of degradation, NPCS paced-up the process, suggesting potential environmental benefits. PCL/NPCS (90/10) fibers exhibit a 99 % coronavirus inhibition within a five-minute exposure without cellular toxicity, while also meeting breathability standards for medical masks. These findings suggest the use of NPCS as a promising strategy to design materials with remarkable virucidal performance and physical characteristics that reinforce their use in the field of biomaterials engineering.

Behind the mask: Stuttering, anxiety, and communication dynamics in the era of COVID-19.

BACKGROUND: While wearing masks during the pandemic poses communication and social challenges for people in everyday life, those with social anxiety might find them plausible, aligning with contemporary cognitive theories. Social anxiety involves fearing negative assessments and holding a negative self-image. Concealing anxiety symptoms during mask use may contribute to a more positive self-perception. AIMS: Given that up to 60% of adults seeking stuttering treatment also meet criteria for social anxiety disorder, this study aims to investigate the complex relationship between communication freedom, self-perceived stuttering and anxiety in adults who stutter (AWS). The unique context of mandatory mask-wearing during the pandemic provides an opportunity to explore these dynamics and understand the conflicting relationships between stuttering, anxiety-related safety behaviours and the need for open communication in AWS. METHODS AND PROCEDURES: Twenty AWS participated in interviews, responding to open-ended questions to elucidate their affective, cognitive and behavioural experiences while wearing masks during the COVID-19 pandemic. Thematic analysis was used to identify the emerging themes and subthemes based on information-rich quotes, employing a six-phase recursive process. Various speech and anxiety-related measures were used to describe the characteristics of the study participants. OUTCOMES AND RESULTS: Three main themes and sub-themes emerged. The first theme highlights communication challenges for AWS wearing masks, impacting verbal and nonverbal interactions. The second theme reveals AWS wearing masks to conceal stuttering cues, experiencing reduced stress. The third theme indicates that, despite the comfort in concealment, most AWS prefer speaking freely without a face mask. CONCLUSIONS AND IMPLICATIONS: The conflict between the desire for authentic, fluent communication and the ease of hiding stuttering symptoms poses a major dilemma for AWS. According to the results of this study, most adults who stutter prioritize open communication. However, there were some individual differences. A major factor influencing their decision was their fear of negative evaluation. WHAT THIS PAPER ADDS: What is already known on the subject The prevalence of social anxiety is higher among adults who stutter (AWS), possibly stemming from their prior negative experiences with stuttering. In response, AWS may adopt adaptive or maladaptive coping behaviours to manage stuttering and mitigate fears of negative evaluation. Maladaptive strategies, like avoiding certain communication situations, can diminish their satisfaction with everyday speaking situations. What this study adds This study leveraged the mask-wearing mandate during the pandemic to explore the intricate relationship between anxiety-related symptoms and communication. While some participants saw masks as a plausible means to conceal stuttering and anxiety, most preferred open communication without the challenges posed by masks. Our findings offer additional support for the varied emotional, cognitive and behavioural responses that AWS may display in response to changes in daily life, emphasizing the individual differences within this population and highlighting that stuttering goes beyond observable speech dysfluencies. What are the clinical implications of this work? Our study underscores the need for comprehensive therapeutic interventions addressing both the physical and cognitive-emotional aspects of stuttering in AWS. Recognizing the role of safety behaviours and self-focused attention emphasizes the importance of an integrated approach, enhancing communication efficacy and social well-being for AWS. Addressing speech fluency alone, without considering pertinent cognitive-emotional factors, falls short in providing adequate stuttering treatment.

Psychological and psychosocial determinants of COVID related face covering behaviours: A systematic review.

Background: The COVID-19 pandemic, caused by the SARS-CoV-2 virus, has resulted in illness, deaths and societal disruption on a global scale. Societies have implemented various control measures to reduce transmission of the virus and mitigate its impact. Individual behavioural changes are crucial to the successful implementation of these measures. One commonly recommended measure to limit risk of infection is face covering. It is important to identify those factors that can predict the uptake and maintenance of face covering. Objectives: We aimed to identify and synthesise the evidence on malleable psychological and psychosocial factors that determine uptake and adherence to face covering aimed at reducing the risk of infection or transmission of COVID-19. Search Methods: We searched various literature sources including electronic databases (Medline ALL, Child Development & Adolescent Studies, ERIC, PsycInfo, CINAHL & Web of Science), web searches, conference proceedings, government reports, other repositories of literature and grey literature. The search strategy was built around three concepts of interest including (1) context (terms relating to COVID19), (2) behaviour of interest and (3) terms related to psychological and psychosocial determinants of COVID Health-Related Behaviours and adherence or compliance with face covering, to capture malleable determines. Searches capture studies up until October 2021. Selection Criteria: Eligibility criteria included observational studies (both retrospective and prospective) and experimental studies that measure and report malleable psychological and psychosocial determinants and handwashing at an individual level, amongst the general public. Screening was supported by the Cochrane Crowd. Studies titles and abstracts were screened against the eligibility criteria by three independent screeners. Following this, all potentially relevant studies were screened at full-text level by the research team. All conflicts between screeners were resolved by discussion between the core research team. Data Collection and Analysis: All data extraction was managed in EPPI-Reviewer software. All eligible studies, identified through full-text screening were extracted by one author. We extracted data on study information, population, determinant, behaviour and effects. A second author checked data extraction on 20% of all included papers. All conflicts were discussed by the two authors until consensus was reached. We assessed methodological quality of all included studies using an adapted version of the Joanna Briggs Institute Quality appraisal tool for cross-sectional studies. Main Results: Our initial searches yielded 23,587 results, of which 23 were included in this review. The included studies were cross-sectional in design, came from nine countries and had a combined sample of 54,401 participants. The vast majority of studies had samples from the general public, with five of the studies focusing on specific samples. All included studies considered people over the age of 18. The quality of 10 of the studies was rated as unclear, 10 were rated as low, and 3 rated high risk of bias, predominately due to lack of reporting of recruitment, sample characteristics and methodology. Ten studies were included in the meta-analysis and 16 in the narrative synthesis. Findings from the meta-analysis indicated that knowledge of COVID-19 (0.341, 95% confidence interval [CI] = 0.06, 0.530, I 2 = 100%) was the malleable determinant most associated with face covering behaviour. Perceived susceptibility of COVID-19 (r = 0.088, 95% CI = -0.004, 0.180, I 2 = 80%) and COVID-related worry and anxiety (r = 0.064, 95% CI = -0.066, 0.191, I 2 = 93% had little to no effect on face covering behaviour. In the narrative synthesis, the strongest association was found between perceived benefits and effectiveness of behaviours and mask wearing behaviour. Authors' Conclusions: Understanding the effects of various malleable determinants on COVID-related face covering can aid in the development and implementation of interventions and public health campaigns to promote face covering behaviour in potential new waves of COVID-19 or other respiratory infections. Knowledge of COVID and perceived benefits of face coverings warrant further consideration in future research and policy.

Masked emotions: does children's affective state influence emotion recognition?

Introduction: Facial emotion recognition abilities of children have been the focus of attention across various fields, with implications for communication, social interaction, and human behavior. In response to the COVID-19 pandemic, wearing a face mask in public became mandatory in many countries, hindering social information perception and emotion recognition. Given the importance of visual communication for children's social-emotional development, concerns have been raised on whether face masks could impair their ability to recognize emotions and thereby possibly impact their social-emotional development. Methods: To this extent, a quasiexperimental study was designed with a two-fold objective: firstly, to identify children's accuracy in recognizing basic emotions (anger, happiness, fear, disgust, sadness) and emotional neutrality when presented with faces under two conditions: one with no-masks and another with faces partially covered by various types of masks (medical, nonmedical, surgical, or cloth); secondly, to explore any correlation between children's emotion recognition accuracy and their affective state. Sixty-nine (69) elementary school students aged 6-7 years old from Greece were recruited for this purpose. Following specific requirements of the second phase of the experiment students were assigned to one of three (3) distinct affective condition groups: Group A-Happiness, Group B-Sadness, and Group C-Emotional Neutrality. Image stimuli were drawn from the FACES Dataset, and students' affective state was registered using the self-reporting emotions-registration tool, AffectLecture app. Results: The study's findings indicate that children can accurately recognize emotions even with masks, although recognizing disgust is more challenging. Additionally, following both positive and negative affective state priming promoted systematic inaccuracies in emotion recognition. Most significantly, results showed a negative bias for children in negative affective state and a positive bias for those in positive affective state. Discussion: Children's affective state significantly influenced their emotion recognition abilities; sad affective states led to lower recognition overall and a bias toward recognizing sad expressions, while happy affective states resulted in a positive bias, improving recognition of happiness, and affecting how emotional neutrality and sadness were actually perceived. In conclusion, this study sheds light on the intriguing dynamics of how face masks affect children's emotion recognition, but also underlines the profound influence of their affective state.

Lesson learned from the COVID-19 pandemic: toddlers learn earlier to read emotions with face masks.

In a prior study we demonstrated that the presence of face masks impairs the human capability of accurately inferring emotions conveyed through facial expressions, at all ages. The degree of impairment posed by face covering was notably more pronounced in children aged between three and five years old. In the current study, we conducted the same test as a follow-up after one year from the onset of the COVID-19 pandemic, when the requirement of wearing face masks was holding in almost all circumstances of everyday life when social interactions occur. The results indicate a noteworthy improvement in recognizing facial expressions with face masks among children aged three to five, compared to the pre-pandemic settings. These findings hold a significant importance, suggesting that toddlers effectively mitigated the social challenges associated with masks use: they overcame initial environmental limitations, improving their capability to interpret facial expressions even in the absence of visual cues from the lower part of the face.

Variation in the fitted filtration efficiency of disposable face masks by sex.

BACKGROUND & OBJECTIVE: Disposable face masks are a primary protective measure against the adverse health effects of exposure to infectious and toxic aerosols such as airborne viruses and particulate air pollutants. While the fit of high efficiency respirators is regulated in occupational settings, relatively little is known about the fitted filtration efficiencies of ear loop style face masks worn by the public. METHODS: We measured the variation in fitted filtration efficiency (FFE) of four commonly worn disposable face masks, in a cohort of healthy adult participants (N = 100, 50% female, 50% male, average age = 32.3 ± 9.2 years, average BMI = 25.5 ± 3.4) using the U.S. Occupational Safety and Health Administration Quantitative Fit Test, for an N95 (respirator), KN95, surgical, and KF94 masks. The latter three ear loop style masks were additionally tested in a clip-modified condition, tightened using a plastic clip to centrally fasten loops in the back of the head. RESULTS: The findings show that sex is a major determinant of the FFE of KN95, surgical, and KF94 masks. On average, males had an 11% higher FFE relative to females, at baseline testing. We show that a simple modification using an ear loop clip, results in improvements in the average FFE for females but provides comparatively minor changes for males. On average, females had a 20% increased FFE when a clip was worn behind the head, relative to a 6% increase for males. IMPACT: The efficacy of a disposable face mask as protection against air contaminants depends on the efficiency of the mask materials and how well it fits the wearer. We report that the sex of the wearer is a major determinant of the baseline fitted filtration efficiency (FFE) of commonly available ear loop style face masks. In addition, we show that a simple fit modifier, an ear loop clip fastened behind the head, substantially improves baseline FFE for females but produces only minor changes for males. These findings have significant public health implications for the use of face masks as a protective intervention against inhalational exposure to airborne contaminants.

Bioaerosols emission from source facilities in a wastewater treatment plant: Critical exposure time and sensitivity analysis.

Overexposure of sewage workers to bioaerosol released from wastewater treatment plants (WWTPs) can cause serious infections, but practical method for controlling their health risk is lacking. In this study, reverse quantitative microbial risk assessment was used to estimate the daily critical exposure time (CET) of sewage workers exposing to Staphylococcus aureus bioaerosol emitted by three emission sources facilities in a WWTP based on either U.S. EPA or WHO benchmark, and sensitivity analysis was conducted to analyze the influence of various parameters on the outcomes of CET. The results showed that the CET of females was always 1.12-1.29 times that of males. In addition, the CET after wearing face masks was 28.28-52.37 times as long as before. The working time can be determined based on the CET results of male workers wearing face masks exposed to the inverted-umbrella aeration tank (14.73-550.98 min for U.S. EPA benchmark and 55.07-1972.24 min for WHO benchmark). In each scenario, the variable parameter exposure concentration (ec) always showed the most influence on the CET results. After wearing the face masks, the removal fraction by employing face masks also had a significant effect on the results, only second to ec. Therefore, the wearing of face mask is the most convenient and effective measure to prolong the CET. Furthermore, practical methods to reducing bioaerosol concentration in WWTPs exposure are also necessary to extend CET and safeguard worker health. This study enriches the application range of reverse quantitative microbial risk assessment framework and provides theoretical support for stakeholders to establish reasonable working time threshold guidelines, and practical method and novel perspective to protect the on-site health risks of sewage workers exposing to various facilities.

Assessment and design of filters and masks against COVID-19 via modeling and simulations.

This study aimed to evaluate and design masks against viruses, especially SARS-CoV-2 associated with COVID-19. A continuum filtration model was developed where the rate of particle deposition and "sticking" on the filter fibers is a critical term in the mass transfer, together with permeation velocity, filter porosity, tortuosity, and Brownian diffusion. CFD simulations of the airflow during respiration lead to the recommendation that the filter permeability should be above 4 × 10-11 m2 to direct the airflow for effectiveness against virus particles; otherwise, low filter permeabilities cause the unfiltered air to flow preferentially through the leak gaps between the mask and the headform. Different mask filters with microstructural and geometry data from the literature are assessed via filtration simulations for breathability and filtration efficiency. The results demonstrate that a surgical mask of 25% porosity, pore size of 150 µm and permeability of 4.4 × 10-11 m2 can achieve 100% minimum efficiency while demonstrating high breathability, complying with the criteria of FFP3, N95, and surgical Class II and IIR masks. Selected cotton and synthetic cloths as well as electrospun fiber layers are predicted to comply with FFP2, N95, and surgical mask Class II and IIR standards.

Comparison of incidence of sore throat with laryngeal mask airway Protector and laryngeal mask airway ProSeal: A randomised clinical trial.

Background and Aims: Postoperative sore throat (POST) can be as high as 42% in supraglottic devices. LMA® Protector™ is a novel second-generation laryngeal mask airway (LMA) with Cuff Pilot™ technology that allows continuous cuff pressure monitoring. Elevated cuff pressure is a risk factor for POST in supraglottic devices, so we conducted this study to determine whether continuous cuff pressure monitoring can alleviate POST. Methods: This randomised double-blinded clinical trial compared the incidence of sore throat between LMA® Protector™ and LMA® ProSeal™ and was conducted in 118 patients scheduled for elective short surgical procedures. They were randomised to either LMA® Protector™ (Group PT) or LMA® ProSeal™ (Group P). The airway was secured with either of the two devices. The primary outcome was the incidence of sore throat at 1, 6, and 24 hours postoperatively and compared using the Chi-square test along with other parameters like first attempt success rate and blood staining of the device. The time taken for insertion and oropharyngeal seal pressure were compared using an independent t-test. Results: The incidence of POST was low with Group PT (12%) compared to Group P (28.8%) (P = 0.005). The mean oropharyngeal seal pressure was significantly higher in Group PT than in Group P [33.72 (3.07) versus 27.72 (3.88) cm of H2O], P < 0.005. The first attempt success rate was 81.2% and 100% in LMA® Protector™ versus LMA® ProSeal™. Conclusion: LMA® Protector™ had a reduced incidence of POST compared to LMA ProSeal. However, a longer insertion time and difficult placement may be a concern.

An investigation into the aging mechanism of disposable face masks and the interaction between different influencing factors.

In the natural environment, a symphony of environmental factors including sunlight exposure, current fluctuations, sodium chloride concentrations, and sediment dynamics intertwine, potentially magnifying the impacts on the aging process of disposable face masks (DFMs), thus escalating environmental risks. Employing Regular Two-Level Factorial Design, the study scrutinized interactive impacts of ultraviolet radiation, sand abrasion, acetic acid exposure, sodium chloride levels, and mechanical agitation on mask aging. Aging mechanisms and environmental risks linked with DFMs were elucidated through two-dimensional correlation analyses and risk index method. Following a simulated aging duration of three months, a single mask exhibited the propensity to release a substantial quantity of microplastics, ranging from 38,800 ± 360 to 938,400 ± 529 particles, and heavy metals, with concentrations from 0.06 ± 0.02 µg/g (Pb) to 29.01 ± 1.83 µg/g (Zn). Besides, specific contaminants such as zinc ions (24.24 µg/g), chromium (VI) (4.20 µg/g), thallium (I) (0.92 µg/g), tetracycline (0.51 µg/g), and acenaphthene (1.73 µg/g) can be adsorbed significantly by aged masks. The study elucidates pivotal role of interactions between ultraviolet radiation and acetic acid exposure in exacerbating the environmental risks associated with masks, while emphasizing the pronounced influence of many other interactions. The research provides a comprehensive understanding of the intricate aging processes and ensuing environmental risks posed by DFMs, offering valuable insights essential for developing sustainable management strategies in aquatic ecosystems.

How College Students Used Information From Institutions of Higher Education in the United States During COVID-19: Web-Based Cross-Sectional Survey Study.

BACKGROUND: The start of the COVID-19 pandemic resulted in the implementation of nonpharmaceutical interventions by US institutions of higher education at an unprecedented level. During the backdrop of an emerging pandemic, younger adults (eg, college students) had an overall lower risk for severe outcomes for SARS-CoV-2, making this population a potential source of transmission for age groups with high susceptibility and negative health outcomes. We examine how college students' level of concern for COVID-19 was influenced by different sources of information, their living status, income level, and other demographic identifiers and its association with prevention behavior change. OBJECTIVE: We sought to examine the level of concern, defined as the extent to which the participant would take corrective action to mitigate contracting or spreading the virus (to family or friends) by using personal protective equipment such as a face mask, practicing social distancing, and following other public health recommendations, among college students during the COVID-19 pandemic. METHODS: A cross-sectional, web-based survey was conducted in 2021 among 185 college students aged 18-41 years, with most living in New York City and the United States (n=134, 72.4%). Out of 185 college students, 94 provided their zip codes, with 51 of those college students indicating they lived in New York City areas. The participants completed the survey via a QR code. Study participants who did not complete the full survey or were not college students in any US college or university were excluded. Analyses were conducted using R (version 4.2.2; R Foundation for Statistical Computing). RESULTS: Of 185 respondents participated in the study, 25 (13.5.%) used emails from their schools, 51 (27.6%) used mainstream media, and 109 (58.9%) used social media and other sources to obtain information about COVID-19. Of the 109 participants who learned about the pandemic from social media, 91 (83.5%) were concerned; however, only 63% (32/51) and 60% (15/25) of the participants who sourced information from mainstream media and their schools' email, respectively, were concerned. Further, the participants who received information from social media and other sources were about 3 times more likely to be concerned about COVID-19 than participants who received information from the university via email (P=.036; OR=3.07, 95% CI: 1.06-8.83).. CONCLUSIONS: College students who received information from social media and other sources were more likely to be concerned about COVID-19 than students who received information from their school via emails.