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Respirable particulate matter (RSP) is currently very harmful to the human body, potentially causing pulmonary silicosis, allergic rhinitis, acute bronchitis, and pulmonary heart disease. Therefore, the study of the deposition pattern of RSP in the human respiratory system is key in the prevention, treatment, and research of related diseases, whereby the main methods are computer simulation, in vitro solid models, and theoretical analysis. This paper summarizes and analyzes past deposition of RSP in the respiratory tract and also describes them in specific case studies such as COPD and COVID-19 patients, based on the review of the evidence, direction, and focus of future research focusing on simulation, experimentation, and related applications of RSP deposition in the respiratory tract. © 2023 by the authors.
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This paper reports a study on the statistics for particulate matter pollution (PM₂.₅) and the COVID-19 lockdown in the Kathmandu valley. The PM₂.₅ decreased during the COVID-19 pandemic lockdown periods 2020 compared to the average value of the previous three years (2017, 2018, and 2019). Further, analysis of active fire and air mass trajectory for April and May in 2019 and 2020 shows that the particulate matter trend associated with Kathmandu is not directly influenced by the long-range transport of wind carrying aerosols from the active fire regions. Statistical tests indicate a reduction of particulate matter pollution during the period.
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Aerosolization of immunotherapies poses incredible potential for manipulating the local mucosal-specific microenvironment, engaging specialized pulmonary cellular defenders, and accessing mucosal associated lymphoid tissue to redirect systemic adaptive and memory responses. In this review, we breakdown key inhalable immunoengineering strategies for chronic, genetic, and infection-based inflammatory pulmonary disorders, encompassing the historic use of immunomodulatory agents, the transition to biological inspired or derived treatments, and novel approaches of complexing these materials into drug delivery vehicles for enhanced release outcomes. Alongside a brief description of key immune targets, fundamentals of aerosol drug delivery, and preclinical pulmonary models for immune response, we survey recent advances of inhaled immunotherapy platforms, ranging from small molecules and biologics to particulates and cell therapies, as well as prophylactic vaccines. In each section, we address the formulation design constraints for aerosol delivery as well as advantages for each platform in driving desirable immune modifications. Finally, prospects of clinical translation and outlook for inhaled immune engineering are discussed.
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Air quality network data in China and South Korea show very high year-round mass concentrations of coarse particulate matter (PM), as inferred by the difference between PM10 and PM2.5. Coarse PM concentrations in 2015 averaged 52 µg m-3 in the North China Plain (NCP) and 23 µg m-3 in the Seoul Metropolitan Area (SMA), contributing nearly half of PM10. Strong daily correlations between coarse PM and carbon monoxide imply a dominant source from anthropogenic fugitive dust. Coarse PM concentrations in the NCP and the SMA decreased by 21 % from 2015 to 2019 and further dropped abruptly in 2020 due to COVID-19 reductions in construction and vehicle traffic. Anthropogenic coarse PM is generally not included in air quality models but scavenges nitric acid to suppress the formation of fine particulate nitrate, a major contributor to PM2.5 pollution. GEOS-Chem model simulation of surface and aircraft observations from the Korea–United States Air Quality (KORUS-AQ) campaign over the SMA in May–June 2016 shows that consideration of anthropogenic coarse PM largely resolves the previous model overestimate of fine particulate nitrate. The effect is smaller in the NCP which has a larger excess of ammonia. Model sensitivity simulations for 2015–2019 show that decreasing anthropogenic coarse PM directly increases PM2.5 nitrate in summer, offsetting 80 % the effect of nitrogen oxide and ammonia emission controls, while in winter the presence of coarse PM increases the sensitivity of PM2.5 nitrate to ammonia and sulfur dioxide emissions. Decreasing coarse PM helps to explain the lack of decrease in wintertime PM2.5 nitrate observed in the NCP and the SMA over the 2015–2021 period despite decreases in nitrogen oxide and ammonia emissions. Continuing decrease of fugitive dust pollution means that more stringent nitrogen oxide and ammonia emission controls will be required to successfully decrease PM2.5 nitrate.
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Six phthalates: dimethyl phthalate (DMP), diethyl phthalate (DEP), di(n-butyl) phthalate (DnBP), butyl benzyl phthalate (BBzP), di(2-ethylhexyl) phthalate (DEHP), and di(n-octyl) phthalate (DOP) in settled dust on different indoor surfaces were measured in 30 university dormitories. A Monte Carlo simulation was used to estimate college students' exposure via inhalation, non-dietary ingestion, and dermal absorption based on measured concentrations. The detection frequencies for targeted phthalates were more than 80% except for DEP (roughly 70%). DEHP was the most prevalent compound in the dust samples, followed by DnBP, DOP, and BBzP. Statistical analysis suggested that phthalate levels were higher in bedside dust than that collected from table surfaces, indicating a nonuniform distribution of dust-phase phthalates in the sleep environment. The simulation showed that the median DMP daily intake was 0.81 μg/kg/day, which was the greatest of the targeted phthalates. For the total exposures to all phthalates, the mean contribution of exposures during the daytime and sleeping time was 54% and 46%, respectively.
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Presentations spanned a range of applications: the public health impacts of poor air quality and environmental justice;greenhouse gas measuring, monitoring, reporting, and verification (GHG MMRV);stratospheric ozone monitoring;and various applications of satellite observations to improve models, including data assimilation in global Earth system models. The combination of methane (CH4), carbon dioxide (CO2), carbon monoxide (CO), and NO2 retrievals can improve confidence in emissions inventories and model performance, and together these data products would be of use in future air quality management tools. The ability to retrieve additional trace gases (e.g., ethane, isoprene, and ammonia) in the thermal IR along with those measured in the UV–Vis–NIR region would be extremely useful for air quality applications, including source apportionment analysis (e.g., for oil/natural gas extraction, biogenic, and agricultural sources). Ground-level ozone is one of six criteria pollutants for which the EPA sets National Ambient Air Quality Standards (NAAQS) to protect against human health and welfare effects.
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The purpose of this study was to measure the number and concentration of airborne particulates occurring in a dental clinic while performing dental procedures, with and without the simultaneous use of air purifier systems and a central ventilation system. The initial background concentrations of airborne particulates recorded during dental procedures, i.e., grinding of natural teeth and metals, without the use of air purifier systems, and with closed windows, reduced by 68% for ΡΜ10, 77% for ΡΜ2.5, and 81% for ΡΜ1 when the same procedures were carried out with the simultaneous use of air purifying systems. In addition, measurements taken during patient treatment showed that an operating central ventilation system contributes to the reduction of airborne particles by a significant 94% for ΡΜ10, 94% for ΡΜ2.5, and 88% for ΡΜ1 compared to dental procedures performed without the simultaneous use of air purifiers. Air purifying systems were also observed to contribute to the further reduction of airborne particulates when dental procedures were performed in combination with an operating central ventilation system. The majority of particles captured had diameters of 0.25-0.30 μm, 0.5 μm, and 1.0-4.0 μm, while particles with diameters of >5.0 μm were the least commonly observed in all experiments. Finally, a statistically significant difference between concentrations of particulate matter was recorded during dental procedures carried out with and without the simultaneous operation of air purifiers and central ventilation system increasing the risk of SARS-CoV-2 virus contamination in dental clinics due to the aerosols emitted by the use of common dental instruments during standard treatments.
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During spring 2020, the COVID-19 pandemic caused massive reductions in emissions from industry and ground and airborne transportation. To explore the resulting atmospheric composition changes, we conducted the BLUESKY campaign with two research aircraft and measured trace gases, aerosols, and cloud properties from the boundary layer to the lower stratosphere. From 16 May to 9 June 2020, we performed 20 flights in the early COVID-19 lockdown phase over Europe and the Atlantic Ocean. We found up to 50% reductions in boundary layer nitrogen dioxide concentrations in urban areas from GOME-2B satellite data, along with carbon monoxide reductions in the pollution hot spots. We measured 20%-70% reductions in total reactive nitrogen, carbon monoxide, and fine mode aerosol concentration in profiles over German cities compared to a 10-yr dataset from passenger aircraft. The total aerosol mass was significantly reduced below 5 km altitude, and the organic aerosol fraction also aloft, indicative of decreased organic precursor gas emissions. The reduced aerosol optical thickness caused a perceptible shift in sky color toward the blue part of the spectrum (hence BLUESKY) and increased shortwave radiation at the surface. We find that the 80% decline in air traffic led to substantial reductions in nitrogen oxides at cruise altitudes, in contrail cover, and in resulting radiative forcing. The light extinction and depolarization by cirrus were also reduced in regions with substantially decreased air traffic. General circulation-chemistry model simulations indicate good agreement with the measurements when applying a reduced emission scenario. The comprehensive BLUESKY dataset documents the major impact of anthropogenic emissions on the atmospheric composition.
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Trends and sources of air pollution at twenty-five traffic Intersections (TIs) before and during covid-19 lockdown were investigated in Ibadan, Nigeria. The relationships among climatic parameters, vehicular counts and ten air pollutants which includes particulate matter (PM1, PM2.5, PM10 & Total Suspended Particles-TSP) and gaseous pollutants (CO, NO2, SO2, NH3, total volatile organic compounds-TVOCs, and ground level O3) measured simultaneously at TIs were analysed. Results indicated significant decrease in mean concentrations of all pollutants studied except NO2 with 212% increase during the study period. Concentrations of gaseous pollutants CO, SO2, NH3, TVOCs and ground level O3 reduced by 7.92%, 24.80%, 1.58%, 44.08% and 4.28%, respectively while particulates concentrations of PM1, PM2.5, PM10 and TSP concentrations decreased by 49.64%, 60.79%, 81.21% and 84.17%, respectively during lockdown. An integrated source apportionment approach using Pearson’s correlation, Airflow backward trajectories arriving in the study area and Principal component analysis (PCA) identified vehicular emission as the primary source of studied air pollutants at TIs before and during lockdown in Ibadan. Emission from residences, roadside fuel combustion and local air transport of pollutants from nearby upwind areas with industries and farming activities were identified as secondary sources of air pollution affecting the study area. © 2022, University of Ilorin, Faculty of Engineering and Technology. All rights reserved.
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A knowledge gap exists concerning how chemical composition and sources respond to implemented policy control measures for aerosols, particularly in a semi-arid region. To address this, a single year's offline measurement was conducted in Hohhot, a semi-arid city in northern China, to reveal the driving factors of severe air pollution in a semi-arid region and assess the impact of the COVID-19 lockdown measures on chemical characteristics and sources of PM2.5. Organic matter, mineral dust, sulfate and nitrate accounted for 31.5 %, 14.2 %, 13.4 % and 12.3 % of the total PM2.5 mass, respectively. Coal combustion, vehicular emission, crustal source and secondary inorganic aerosols were the main sources of PM2.5 in Hohhot, at 38.3 %, 35.0 %, 13.5 %, and 11.4 %, respectively. Due to the coupling effect of emission reduction and improved atmospheric conditions, the concentration of secondary inorganic components, organic matter and elemental carbon declined substantially from the pre-lockdown (pre-LD) period to the lockdown (LD) and post-lockdown (post-LD) periods. The source contribution of secondary inorganic aerosols increased (from 21.1 % to 37.8 %), whereas the contribution of vehicular emission reduced (from 35.5 % to 4.4 %) due to lockdown measures. The rapid generation of secondary inorganic components caused by unfavorable meteorological conditions during lockdown led to serious pollution. This study elucidates the complex relationship between air quality and environmental policy.
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In the present situation, Covid-19 is considered to be an unbeaten global pandemic. In every single fleeting moment, this SARS-CoV-2 (coronavirus-2) causes greater damage to our life including the physical world including drastic imbalance of the whole economic condition of any country. The lockdown governed in two consecutive years (2020 and 2021) in the world to control the spreading of the virus poses an undue threat to the industrial sectors including the coal mining sectors that determine the economic growth of the country. With these negative impacts of coronavirus-2 in our life, this present review aims to explore some of the positive influences of the Covid-19 pandemic through the restoration of the environmental system which are otherwise not possible. This quantitative review finds that spreading of the Covid-19 pandemic indirectly improves the air and water quality by reducing the number of vehicles, reduces the CO2, NOx, particulate matter, and other polluting gases emission from coal-based power plants through periodical lockdown in the country. Moreover, the lockdown implemented to minimise the spreading of the Covid-19 significantly reduces the coal dust production from the mining and transportation of coal that indirectly reduces environmental pollution.
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Due to the complexity of emission sources, a better understanding of aerosol optical properties is required to mitigate climate change in China. Here, an intensive real-time measurement campaign was conducted in an urban area of China before and during the COVID-19 lockdown in order to explore the impacts of anthropogenic activities on aerosol light extinction and the direct radiative effect (DRE). The mean light extinction coefficient (bext) decreased from 774.7 ± 298.1 Mm-1 during the normal period to 544.3 ± 179.4 Mm-1 during the lockdown period. A generalised additive model analysis indicated that the large decline in bext (29.7 %) was due to sharp reductions in anthropogenic emissions. Chemical calculation of bext based on a ridge regression analysis showed that organic aerosol (OA) was the largest contributor to bext in both periods (45.1 %–61.4 %), and the contributions of two oxygenated OAs to bext increased by 3.0 %–14.6 % during the lockdown. A hybrid environmental receptor model combined with chemical and optical variables identified six sources of bext. It was found thatbext from traffic-related emissions, coal combustion, fugitive dust, the nitrate and secondary OA (SOA) source, and the sulfate and SOA source decreased by 21.4 %–97.9 % in the lockdown, whereas bext from biomass burning increased by 27.1 %, mainly driven by the undiminished need for residential cooking and heating. An atmospheric radiative transfer model was further used to illustrate that biomass burning, rather than traffic-related emissions, became the largest positive effect (10.0 ± 10.9 W m-2) on aerosol DRE in the atmosphere during the lockdown. Our study provides insights into aerosol bext and DRE from anthropogenic sources, and the results imply the importance of controlling biomass burning for tackling climate change in China in the future.
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Bioaerosols, in addition to common gaseous or particulate pollutants, are also important air pollutants that deteriorate indoor air quality. Bioaerosols are the airborne particles present as or originating from living organisms such as fungi, bacteria, and viruses and include toxins, fragments, or waste product from various organisms. In this chapter, the characteristics of indoor bioaerosols are provided. The common type and sources of bioaerosols are summarized. These biological pollutants are commonly generated both by the activities and behaviors of the occupants, and by housing materials and substances that penetrate from the outdoor environment. Fungi and bacteria are the most common bioaerosols present in the indoor environment. After exposure, occupants may experience adverse health outcomes such as infection or allergy. If the indoor environment is severely contaminated, as observed in many places during the COVID-19 pandemic, especially in public areas, a large number of people may be affected by contamination. This chapter also summarizes monitoring and assessment technologies. The monitoring procedure can be chosen and performed according to the objective of the assessment. Advance technologies such as real-time sensor monitoring, Internet of Things, and artificial intelligence have been integrated, but their use for bioaerosols monitoring is still limited as compared to their use for other types of indoor air pollutants. Effective control strategies to reduce the contamination of indoor bioaerosols are also provided in this chapter that could benefit occupants to reduce the contamination and minimize exposure. © 2022, The Author(s), under exclusive license to Springer Nature Switzerland AG.
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Objective/Scope: One of the main concerns of Oil & Gas Plants and associated Buildings is how to improve indoor air quality (IAQ) and tackling viruses. IAQ can be affected, or may become under high risk by some of nearby gases, microbial contaminates or energy stressor that affect the HSE condition. This paper presents the main factors that been considered to provide practical solutions to achieve high IAQ and tackling viruses (such as COVID-19). Methods, Procedures, Process: IAQ refers to the air quality within and around the plants/buildings. IAQ can usually be affected, or may become under high risk by nearby gases, particulates, microbial contaminates or any mass that affect 100% HSE. Inadequate air quality in building will increase the risk and impact on transferring viruses to people (such as COVID and Flue) and equipment performance (such as equipment failure, components corrosion and short circuits on control board). Survey and data was recorded to evaluate air quality performance in atmosphere instead of assuming it. Accordingly, the impact of inadequate IAQ was studied and evaluated. Results, Observations & Conclusions: The international standard set a good IAQ in respect of gas concentration and human who works inside buildings in a way that less than 50% people should not detect any odor, 25% should not experience discomfort, 10% should not suffer from mucosal irritation and 5% should not experience annoyance. Study concluded that inadequate IAQ inside the building will affect people performance/health and installed equipment performance. In addition, improper HVAC system operation will be become breeding site for odor causing mold and bacteria, specifically on cooling coil. Hence, several technics were studied to improve IAQ, by installing Ultraviolet (UV) light to stop growing bacterial inside the HVAC system, installing chemical filter in air intakes to remove atmospheric dust, gases and bacteria by 100%, upgrading filtration efficiency to MERV-13 or highest achievable to capture at least 75 - 95% of airborne particles between 0.3 and 1.0 micron, increase outdoor air ventilation and temperature/humidity control. The performance of HVAC system and quality of air inside building were monitored by simulating IAQ based on ISO 16890, filters life cycle, energy consumption, and the results were found 100% satisfactory and provided solutions that are now successfully implemented in all new and some of the existing buildings. Novel/Additive Information: There are several buildings with similar issues and these approach/technics now being adopted in new constructed/existing buildings to protect human and asset integrity, which will support ADNOC Way by sustaining safe environment operation, lower health risk, reduce of equipment failure, reduce maintenance cost and 100% HSE. There are numbers of occupied buildings across the world were surrounded by aggressive gases/pollution with poor IAQ and above approaches it can be followed to realize larger benefits. © Copyright 2021, Society of Petroleum Engineers
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Physical activity reduces morbidity and mortality from a wide range of conditions, and public health advice encourages people to walk 10 000 steps each day. Indoor air quality Airborne particulates exacerbate chronic obstructive pulmonary disease, so it’s disappointing that a trial of portable particulate air cleaners used in the home showed no benefit. [...]in an intention-to-treat analysis, the primary outcome of respiratory specific quality of life was unchanged (Am J Respir Crit Care doi:10.1164/rccm.202103-0604OC) Changing incidence of metastatic prostate cancer Population based data from the US reveal an increasing incidence of metastatic prostate cancer during the period 2010-18.
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This paper concerns an in-depth analysis of an exceptional incursion of mineral dust over southern Europe in late March 2020 (27–30 March 2020). This event was associated with an anomalous circulation pattern leading to several days of PM10 (particulate matter with an aerodynamic diameter less than 10 µm) exceedances in connection with a dust source located in central Asia;this is a rare source of dust for Europe, which is more frequently affected by dust outbreaks from the Sahara Desert. The synoptic meteorological configuration was analyzed in detail, and the aerosol evolution during the transit of the dust plume over northern Italy was assessed at high time resolution by means of optical particle counting at three stations, namely Bologna, Trieste, and Mt. Cimone, allowing for the revelation of the transport timing among the three locations. Back-trajectory analyses supported by Copernicus Atmosphere Monitoring Service (CAMS) maps allowed for the location of the mineral dust source area in the Aralkum region. Therefore, the event was analyzed by observing the particle number size distribution with the support of chemical composition analysis. It is shown that the PM10 exceedance recorded is associated with a large fraction of coarse particles, which is in agreement with mineral dust properties. Both the in situ number size distribution and the vertical distribution of the dust plume were cross-checked using lidar ceilometer and aerosol optical depth (AOD) data from two nearby stations and showed that the dust plume (in contrast to those originating from the Sahara Desert) traveled close to the ground (up to a height of about 2 km). The limited mixing layer height caused by high concentrations of absorbing and scattering aerosols caused the mixing of mineral dust with other locally produced ambient aerosols, thereby potentially increasing its morbidity effects.
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Lidar observations were analysed to characterize atmospheric pollen at four EARLINET (European Aerosol Research Lidar Network) stations (Hohenpeißenberg, Germany;Kuopio, Finland;Leipzig, Germany;and Warsaw, Poland) during the ACTRIS (Aerosol, Clouds and Trace Gases Research Infrastructure) COVID-19 campaign in May 2020. The reanalysis (fully quality-assured) lidar data products, after the centralized and automatic data processing with the Single Calculus Chain (SCC), were used in this study, focusing on particle backscatter coefficients at 355 and 532 nm and particle linear depolarization ratios (PDRs) at 532 nm. A novel method for the characterization of the pure pollen depolarization ratio was presented, based on the non-linear least square regression fitting using lidar-derived backscatter-related Ångström exponents (BAEs) and PDRs. Under the assumption that the BAE between 355 and 532 nm should be zero (±0.5) for pure pollen, the pollen depolarization ratios were estimated: for Kuopio and Warsaw stations, the pollen depolarization ratios at 532 nm were of 0.24 (0.19–0.28) during the birch-dominant pollen periods, whereas for Hohenpeißenberg and Leipzig stations, the pollen depolarization ratios of 0.21 (0.15–0.27) and 0.20 (0.15–0.25) were observed for periods of mixture of birch and grass pollen. The method was also applied for the aerosol classification, using two case examples from the campaign periods;the different pollen types (or pollen mixtures) were identified at Warsaw station, and dust and pollen were classified at Hohenpeißenberg station.
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We are interested in determining whether ambient air pollutants impact the development of Parkinson's disease (PD) by increasing -synuclein pathology via inflammation. After completing Specific Aim 2, wherein we found no differences between experimental groups in spread of -syn, nor the expected nPM-induced neuroinflammatory changes. We repeated Specific Aim 2 mouse experiments with a new batch of nPM that showed in vitro activity. We collected tissues during the first week of SARS-CoV-2 quarantine. After restrictions were relaxed, we began analyzing tissues for neuroinflammation. This on-going analysis has yet to show strong inflammatory effects of the in vivo nPM exposure. Due to continued pandemic quarantine and travel restrictions we are discussing option with our collaborators. We will plan and execute novel experiments to explore the effects of LPS-induced olfactory inflammation on spread of -syn by histological (VAI) and biochemical (USC) analyses. We are interested in determining whether ambient air pollutants impact the development of Parkinson's disease (PD) by increasing -synuclein pathology via inflammation. After completing Specific Aim 2, wherein we found no differences between experimental groups in spread of -syn, nor the expected nPM-induced neuroinflammatory changes. We repeated Specific Aim 2 mouse experiments with a new batch of nPM that showed in vitro activity. We collected tissues during the first week of SARS-CoV-2 quarantine. After restrictions were relaxed, we began analyzing tissues for neuroinflammation. This on-going analysis has yet to show strong inflammatory effects of the in vivo nPM exposure. Due to continued pandemic quarantine and travel restrictions we are discussing option with our collaborators. We will plan and execute novel experiments to explore the effects of LPS-induced olfactory inflammation on spread of -syn by histological (VAI) and biochemical (USC) analyses.
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Due to the novel coronavirus spread (COVID-19) globally, governments across the world recommended the mandatory use of facemasks. The facemask helps people prevent and control the spread of virus infection. In this paper, we propose a design and model of facemask to inactivate the virus particles present in our surroundings. The proposed facemask is able to purify the air when a person inhales and exhales. The proposed mask is cost-effective, reusable, washable, and possesses the ability to disinfect the surface of facemask. The mask has the capability to trap all dust particles and virus present in the air, drastically decreasing the chance of infection. The mask is well-designed on the concept of activated carbon and copper filter.
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The face mask is the first line of defense against infectious particulates and droplets that may cause illness. Currently in the Philippines, the wearing of face mask is compulsory whenever citizens leave their residences as mandated by the government to mitigate the spread of COVID-19. The wearing of face masks has become a new normal among Filipinos. This created market opportunities for different types which became commonly and immediately available for purchase. This study aimed to differentiate the effectiveness of locally available face masks in terms of electrostatic filtration capability. Twelve different types of face masks grouped into five categories – surgical, fabric, N95 variants, foam type, and novelty type – were evaluated. Electrostatic fields were measured from each face mask including pore sizes via scanning electron microscopy. Moreover, by utilizing the estimated charge and mass of the SARS-CoV-2 virion, the transmission rate was simulated using COMSOL Multiphysics®. It was observed that face masks with negatively charged materials combined with small pore sizes afforded less particle transmission. The results of this study are of timely significance in potentially laying out public awareness in the selection and utilization of face masks that can provide foremost shielding against viral transmission. © 2021 Institute of Physics Publishing. All rights reserved.