scholarly journals Electrostatic Charge Retention in PVDF Nanofiber-Nylon Mesh Multilayer Structure for Effective Fine Particulate Matter Filtration for Face Masks

Polymers ◽  
2021 ◽  
Vol 13 (19) ◽  
pp. 3235
Author(s):  
Dong Hee Kang ◽  
Na Kyong Kim ◽  
Hyun Wook Kang
Keyword(s):  
Particulate Matter ◽  
Air Pollutants ◽  
Multilayer Structure ◽  
Fine Particulate Matter ◽  
Face Mask ◽  
Filter Membrane ◽  
Nylon Mesh ◽  
Electrostatic Charges ◽  
Normal Breathing ◽  
Fine Particulate

Currently, almost 70% of the world’s population occupies urban areas. Owing to the high population density in these regions, they are exposed to various types of air pollutants. Fine particle air pollutants (<2.5 μm) can easily invade the human respiratory system, causing health issues. For fine particulate matter filtration, the use of a face mask filter is efficient; however, its use is accompanied by a high-pressure drop, making breathing difficult. Electrostatic interactions in the filter of the face mask constitute the dominant filtration mechanism for capturing fine particulate matter; these masks are, however, significantly weakened by the high humidity in exhaled breath. In this study, we demonstrate that a filter with an electrostatically rechargeable structure operates with normal breathing air power. In our novel face mask, a filter membrane is assembled by layer-by-layer stacking of the electrospun PVDF nanofiber mat formed on a nylon mesh. Tribo/piezoelectric characteristics via multilayer structure enhance filtration performance, even under air-powered filter bending taken as a normal breathing condition. The air gap between nanofiber and mesh layers increases air diffusion time and preserves the electrostatic charges within the multi-layered nanofiber filter membrane under humid air penetration, which is advantageous for face mask applications.

Satellite-based observations of ground-level fine particulate matter and comparison to a regional air quality model

2020 ◽  
Author(s):  
Jana Handschuh ◽  
Frank Baier ◽  
Thilo Erbertseder ◽  
Martijn Schaap
Keyword(s):  
Particulate Matter ◽  
Air Quality ◽  
Air Pollutants ◽  
Fine Particulate Matter ◽  
Ground Level ◽  
In Situ Measurements ◽  
Satellite Observations ◽  
Optical Parameters ◽  
Fine Particulate

&lt;p&gt;Particulate matter and other air pollutants have become an increasing burden on the environment and human health. Especially in metropolitan and high-traffic areas, air quality is often remarkably reduced. For a better understanding of the air quality in specific areas, which is of great environment-political interest, data with high resolution in space and time is required. The combination of satellite observations and chemistry-transport-modelling has proven to give a good database for assessments and analyses of air pollution. In contrast to sample in-situ measurements, satellite observations provide area-wide coverage &amp;#8203;&amp;#8203;of measurements and thus the possibility for an almost gapless mapping of actual air pollutants. For a high temporal resolution, chemistry-transport-models are needed, which calculate concentrations of specific pollutants in continuous time steps. Satellite observations can thus be used to improve model performances.&lt;/p&gt;&lt;p&gt;There are no direct satellite-measurements of fine particulate matter (PM2.5) but ground-level concentrations of PM2.5 can be derived from optical parameters such as aerosol optical depth (AOD). A wide range of methods for the determination of PM2.5 concentrations from AOD measurements has been developed so far, but it is still a big challenge. In this study a semi-empirical approach based on the physical relationships between meteorological and optical parameters was applied to determine a first-guess of ground-level PM2.5 concentrations for the year 2018 and the larger Germany region. Therefor AOD observations of MODIS (Moderate Resolution Imaging Spectroradiometer) aboard the NASA Aqua satellite were used in a spatial resolution of 3km. First results showed an overestimation of ground-level aerosols and quiet low correlations with in-situ station measurements from the European Environmental Agency (EEA). To improve the results, correction factors were calculated using the coefficients of linear regression between satellite-based and in-situ measured particulate matter concentrations. Spatial and seasonal dependencies were taken into account with it. Correlations between satellite and in-situ measurements could be improved applying this method.&lt;/p&gt;&lt;p&gt;The MODIS 3km AOD product was found to be a good base for area-wide calculations of ground-level PM2.5 concentrations. First comparisons to the calculated PM2.5 concentrations from chemistry-transport-model POLYPHEMUS/DLR showed significant differences though. Satellite observations will now be used to improve the general model performance, first by helping to find and understand regional and temporal dependencies in the differences. As part of the German project S-VELD funded by the Federal Ministry of Transport and Digital Infrastructure BMVI, it will help for example to adjust the derivation of particle emissions within the model.&lt;/p&gt;

Impact of air pollutants on pediatric admissions for Mycoplasma pneumonia: A cross-sectional study in Shanghai, China

2020 ◽  
Author(s):  
Ning Chen ◽  
Jianwei Shi ◽  
Jiaoling Huang ◽  
Wenya Yu ◽  
Rui Liu ◽  
...  
Keyword(s):  
Particulate Matter ◽  
Hospital Admission ◽  
Nitrogen Dioxide ◽  
Air Pollutants ◽  
Hospital Admissions ◽  
Fine Particulate Matter ◽  
Ambient Air ◽  
Pediatric Hospital ◽  
Fine Particulate ◽  
Mycoplasma Pneumonia

Abstract Background Children are especially vulnerable to pneumonia and the effects of air pollution. However, little is known about the impacts of air pollutants on pediatric admissions for Mycoplasma pneumonia. This study was conducted to investigate the impacts of air pollutants on pediatric hospital admissions for Mycoplasma pneumonia in Shanghai, China.Methods A cross-sectional design was applied to explore the association between pediatric hospital admissions and levels of air pollutants (fine particulate matter, particulate matter, ozone, sulfur dioxide, nitrogen dioxide, and carbon monoxide). Data on hospital admissions for pneumonia and levels of ambient air pollutants were obtained for the period of 2015 to 2018. Associations between pediatric admissions for Mycoplasma pneumonia and ambient air pollutants were calculated using logistic regression and described by the odds ratio and relevant 95% confidence interval. The hysteresis effects of air pollutants from the day of hospital admission to the previous 7 days were evaluated in single-pollutant models and multi-pollutant models with adjustments for weather variables and seasonality. Lag 0 was defined as the day of hospital admission, lag 1 was defined as the day before hospital admission, and so forth.Results In the single-pollutant models (without adjustment for other pollutants), pediatric hospital admissions for pneumonia were positively associated with elevated concentrations of nitrogen dioxide and fine particulate matter. A 0.5% increase in daily admissions per 10-μg/m3 increase in the nitrogen dioxide level occurred at lag 1 and lag 2, and a 0.3% increase in daily admissions per 10-μg/m3 increase in fine particulate matter occurred at lag 1. In the multi-pollutant models, nitrogen dioxide and fine particulate matter remained significant after inclusion of particulate matter, ozone, sulfur dioxide, and carbon monoxide.Conclusions This study illustrated that higher levels of nitrogen dioxide and fine particulate matter increase the risk of hospitalization for Mycoplasma pneumonia in Shanghai, China. These findings imply that the high incidence of Mycoplasma pneumonia in children in Asia might be attributed to the high concentration of specific air pollutants in Asia.

Chronic and Acute Exposure to Ambient Fine Particulate Matter and Other Air Pollutants: National Cohort Studies of Mortality and Morbidity

Epidemiology ◽  
2006 ◽  
Vol 17 (Suppl) ◽  
pp. S70
Author(s):  
Jonathan M. Samet ◽  
Scott L. Zeger ◽  
Francesca Dominici ◽  
Aidan McDermott ◽  
Alison Geyh ◽  
...  
Keyword(s):  
Particulate Matter ◽  
Cohort Studies ◽  
Air Pollutants ◽  
Fine Particulate Matter ◽  
Acute Exposure ◽  
Mortality And Morbidity ◽  
Fine Particulate ◽  
National Cohort

scholarly journals Studying the effect of particulate matter as SARS-CoV-2 transmitters

2021 ◽  
Author(s):  
Abdulrahim R. Hakami ◽  
Gasim Dobie
Keyword(s):  
Particulate Matter ◽  
Air Quality ◽  
Indirect Effects ◽  
Air Pollutants ◽  
Quality Index ◽  
Fine Particulate Matter ◽  
Future Studies ◽  
Fine Particulate ◽  
Difficult Time

Background: Studies of risk factors are especially valuable at this difficult time in the midst of a pandemic. High levels of particulate matter (PM) represent a serious risk factor on health. While this is a direct impact on health, indirect effects are worth considering too.Design and Methods: The aim of this study was to investigate the role of PM in the transmission of viruses, especially SARS-CoV-2. Also, we sought to understand dynamics of PM in still air at high and low altitudes. Historic AQI and physical PM measurements were collected between August and September 2020 using air quality detector. Potential correlations between the number of total confirmed COVID-19 cases and average air quality index (AQI) from varied geographic locations were also assessed.Results: Airborne PM levels were weakly associated with COVID-19 cases after analysing 77 territories. PM remained longer in the air at high altitudes compared to measurements made at sea level. This suggests that the link between PM and COVID-19 transmission could be aggravated in areas of high altitude.Conclusions: This article highlights that particulate matter can be involved in SARS-CoV-2 transmission. However, confounding factors may have impacted the association between the two variables. These findings can serve as a foundation for future studies on the effect of air pollutants and fine particulate matter on viral transmission.

scholarly journals Air Pollution, Stock Return, and Volatility: Evidence from Korean Stock Markets

2020 ◽  
Vol 49 (3) ◽  
pp. 375-413
Author(s):  
Taekyung Kim ◽  
Shiyong Yoo
Keyword(s):  
Air Pollution ◽  
Particulate Matter ◽  
Air Pollutants ◽  
Stock Return ◽  
Fine Particulate Matter ◽  
Cumulative Exposure ◽  
Daily Exposure ◽  
Fine Particulate ◽  
Coarse Particulate Matter ◽  
Trading Ratio

This study analyzes the direct and indirect effects of air pollution on the return and volatility of the KOSPI index through the trading ratio by investor type. The main results are as follows. First, air pollutants have a direct effect on volatility; coarse particulate matter (PM10) and fine particulate matter (PM2.5) have a negative effect on volatility. Second, air pollutants have a significant effect on the trading ratio by investor type; as the concentration of fine particulate matter (PM2.5) increases, the trading ratio of institutionals and those of foreigners decrease. Third, the effect of cumulative exposure of air pollutants on stock return and volatility is greater than that of daily exposure. Although there is no effect on daily exposure to air pollution, stock return decreases during cumulative exposure to fine particulate matter (PM2.5), nitrogen dioxide (NO2), and carbon monoxide (CO). The volatility changes significantly with cumulative exposure compared to daily exposure to coarse particulate matter (PM10), fine particulate matter (PM2.5), ozone (O3), nitrogen dioxide (NO2) and sulfur dioxide (SO2). Fourth, air pollutants have an indirect effect on stock return and volatility through trading ratio by institutional and foreign investors. In particular, the effect of air pollution through the foreign investors’ trading ratio is a remarkable result revealed in this study.

scholarly journals Influence of the Natural and Built Environment on Personal Exposure to Fine Particulate Matter (PM2.5) in Cyclists Using City Designated Bicycle Routes

Urban Science ◽  
2018 ◽  
Vol 2 (4) ◽  
pp. 120 ◽  
Author(s):  
Jason Gilliland ◽  
Matthew Maltby ◽  
Xiaohong Xu ◽  
Isaac Luginaah ◽  
Tayyab Shah
Keyword(s):  
Particulate Matter ◽  
Built Environment ◽  
Air Pollutants ◽  
Fine Particulate Matter ◽  
Personal Exposure ◽  
Construction Sites ◽  
Urban Core ◽  
Fine Particulate ◽  
Under Construction ◽  
Healthy Activity

Urban cyclists are exposed to many traffic-related air pollutants including particulate matter (PM) that may increase vulnerability to health effects. This study investigates second-by-second personal exposure to PM2.5 (fine particulate matter that is 2.5 microns in diameter and less) along bicycle commuting paths, and assesses elements of the natural and built environment for the relative importance of these factors in understanding the variability in PM2.5 personal exposure. Urban cyclists were carrying high resolution PM2.5 monitors (placed in a backpack) in combination with portable GPS trackers to provide a spatial identity to each one-second pollutant measurement. The results of this study indicate that daily averages of PM2.5 concentrations from all bicycle routes were weakly correlated with meteorological variables, however, a strong influence of regional levels of PM2.5 was observed. Geospatial analysis of PM2.5 personal exposure concentrations showed a considerable variation within routes, correlated with land use (with lower concentrations in parks and higher in industrial areas) and clustered at four areas: busiest bridge, heavily trafficked road segments, the downtown urban core, and two construction sites. This study has found many incidences of personal exposure to PM2.5 exceeding the provincial guidelines for healthy activity (e.g., very poor (PM2.5 > 91 μg/m3) pollution concentrations are clustered in three regions: approaching the bridge in the west part of the city; the downtown urban core; and two under construction spots), which suggests behavioural and infrastructure modifications in balancing the health benefits of cycling with the environmental exposure to air pollutants.

scholarly journals Local and regional contributions to fine particulate matter in the 18 cities of Sichuan Basin, southwestern China

2019 ◽  
Author(s):  
Xue Qiao ◽  
Hao Guo ◽  
Ya Tang ◽  
Pengfei Wang ◽  
Wenye Deng ◽  
...  
Keyword(s):  
Particulate Matter ◽  
Air Pollutants ◽  
Sichuan Basin ◽  
Fine Particulate Matter ◽  
Inorganic Aerosols ◽  
Multi Scale ◽  
Fine Particulate ◽  
Non Local ◽  
The Sichuan Basin ◽  
Local Emissions

Abstract. The Sichuan Basin (SCB) is one of the regions suffering from severe air pollution in China, but fewer studies have been conducted for this region than the more developed regions in North and East China. In this study, a source-oriented version of the Community Multi-scale Air Quality (CMAQ) model was used to quantify contributions from nine regions to PM2.5 (i.e., particulate matter (PM) with an aerodynamic diameter less than 2.5 μm) and its components in the 18 cities within the SCB in the winter (December 2014 to February 2015) and summer (June to August, 2015). In the winter, citywide average PM2.5 concentrations are 45~126 μg m−3, with 21~51 % and 39~66 % due to local and non-local emissions, respectively. In the summer, 15~45 % and 25~52 % of citywide average PM2.5 (14~31 μg m−3) are due to local and non-local emissions, respectively. Compared to primary PM (PPM), the inter-region transport of secondary inorganic aerosols (SIA, including ammonia (NH4+), nitrate (NO3−), and sulfate (SO42−)) is greater. The region to the east of SCB (R7) is the largest contributor outside the SCB, and it can contribute approximately 80 % in the northeast, east, and southeast rims of the SCB, but only 10 % in the other regions in both seasons. Under favorable transport conditions, regional transport of air pollutants from R7 could account for up to 35~100 μg m−3 of PM2.5 in each of the SCB cities in the winter. This study demonstrates that it is important to have joint emission control efforts among cities within the SCB and neighbor regions to the east in order to reduce PM2.5 concentrations and prevent high PM2.5 days for the entire basin.

scholarly journals Air Pollution and Emergency Department Visits for Mental Disorders among Youth

2020 ◽  
Vol 17 (12) ◽  
pp. 4190
Author(s):  
Mieczysław Szyszkowicz ◽  
Roger Zemek ◽  
Ian Colman ◽  
William Gardner ◽  
Termeh Kousha ◽  
...  
Keyword(s):  
Mental Health ◽  
Air Pollution ◽  
Particulate Matter ◽  
Nitrogen Dioxide ◽  
Air Pollutants ◽  
Fine Particulate Matter ◽  
Mental Health Disorders ◽  
Fine Particulate ◽  
Ed Visits ◽  
Health Disorders

Although exposure to ambient air pollution has been linked to mental health problems, little is known about its potential effects on youth. This study investigates the association between short-term exposure to air pollutants and emergency department (ED) visits for mental health disorders. The National Ambulatory Care Reporting System database was used to retrieve ED visits for young individuals aged 8–24 years in Toronto, Canada. Daily average concentrations of nitrogen dioxide (NO2), fine particulate matter (PM2.5), and daily maximum 8 h ozone (O3) were calculated using measurement data from seven fixed stations. A case-crossover (CC) design was implemented to estimate the associations between ED visits and air pollution concentrations. Mental health ED visits were identified using International Classification of Diseases 10th Revision (ICD-10) codes, with seven categories considered. Models incorporating air pollutants and ambient temperature (with lags of 0–5 days) using a time-stratified CC technique were applied. Multivariable regression was performed by sex, three age groups, and seven types of mental health disorders to calculate relative risk (RR). The RRs were reported for one interquartile range (IQR) change in the air pollutant concentrations. Between April 2004 and December 2015 (4292 days), there were 83,985 ED visits for mental-health related problems in the target population. Several exposures to air pollutants were shown to have associations with ED visits for mental health including same day exposure to fine particulate matter (IQR = 6.03 μg/m3, RR = 1.01 (95% confidence interval: 1.00–1.02), RR = 1.02 (1.00–1.03)) for all and female-only patients, respectively. One-day lagged exposure was also associated with ED visits for PM2.5 (RR = 1.02 (1.01–1.03)), for nitrogen dioxide (IQR = 9.1 ppb, RR = 1.02 (1.00–1.04)), and ozone (IQR = 16.0 ppb, RR = 1.06 (1.01–1.10)) for males. In this study, urban air pollution concentration—mainly fine particulate matter and nitrogen dioxide—is associated with an increased risk for ED visits for adolescents and young adults with diagnosed mental health disorders.

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