scholarly journals Quantification of the Lung Deposition Load of Smoke Particles by Plastic Type with the Lung Deposition Load Index (LDLIn)

2021 ◽  
Vol 35 (1) ◽  
pp. 28-40
Author(s):  
Jaehark Goo
Keyword(s):  
Particle Size ◽  
Particulate Matter ◽  
Respiratory Tract ◽  
Human Body ◽  
Mass Concentration ◽  
Causative Factor ◽  
Lung Deposition ◽  
Smoke Inhalation ◽  
Smoke Particles ◽  
Index Value

Many fire-related casualties are caused by smoke inhalation. The particulate matter in smoke is deposited on the walls of the respiratory system, and adversely affects the human body through the respiratory and circulatory systems. In order to estimate the adverse effects of smoke particles on the human body, it is reasonable to consider the quantity of harmful substances from smoke particles that are absorbed by each region of the respiratory tract rather than the mass concentration of smoke particles in the air. This is because the absorption amount is a consequent factor that depends on a wide variety of other factors and is not solely determined by the causative factor, that is, the mass concentration in the air. In this study, the lung deposition loads of smoke particles from plastics, such as LDPE, PA66, PMMA, and PVC were quantified using the lung deposition load index (LDLIn), and the results were compared with the findings of conventional particulate matter (PM) mass concentration indices, such as PM2.5 mass and PM10 mass. The LDLIn value was calculated from the number of smoke particles generated during a fire that were deposited in each region of the respiratory tract for the given combustion materials and fire conditions. Herein, the LDLIn quantified the lung deposition load by reflecting the surface area concentration by particle size as well as the deposition characteristics in the respiratory tract according to particle size and breathing conditions. Even at the same PM mass concentration index value, each material and fire condition resulted in different LDLIn values according to the change in concentration distribution by particle size. The LDLIn values also varied depending on the breathing conditions.

Dust Dispersion Modeling of the Urban Environment Air nearby the Potash Production

2018 ◽  
Vol 878 ◽  
pp. 263-268
Author(s):  
G.V. Seimova ◽  
I.V. Stefanenko ◽  
M.S. Kalashnikova
Keyword(s):  
Air Pollution ◽  
Particulate Matter ◽  
Respiratory Tract ◽  
Urban Environment ◽  
Human Body ◽  
Mass Concentration ◽  
Dispersion Modeling ◽  
Small Particles ◽  
Pm10 And Pm2.5 ◽  
Dust Dispersion

Air pollution is one of the most significant problem and threats to human health worldwide. The most common pollutant is particulate matter (PM). For characteristics of the PM and their health effects, commonly used indicator is the mass concentration of particles with diameters less than 10 microns (PM10) and small dispersed suspended particles with diameter less than 2.5 microns (PM2.5), as such small particles are able to penetrate deep into the respiratory tract of the human body. The concentration of particles PM10 and PM2.5 in the air is subjected of rationing. This problem has been explored in many countries with the aim of possible reducing concentrations of PM10 and PM2.5 in the air.

THE DEPOSITION OF AEROSOLS IN THE RESPIRATORY TRACT: II. DEPOSITION IN CIGARETTE SMOKING

1965 ◽  
Vol 43 (5) ◽  
pp. 707-714 ◽  
Author(s):  
J. M. Beeckmans
Keyword(s):  
Particle Size ◽  
Respiratory Tract ◽  
Computer Program ◽  
Program Analysis ◽  
Particle Deposition ◽  
Smoke Inhalation ◽  
Experimental Conditions ◽  
Mean Particle Size ◽  
Basic Equations ◽  
Improved Model

A computer program was developed which calculates the deposition of cigarette smoke particles in the respiratory tract of the smoker. The basic equations used to describe the particle deposition and the mixing of air in the respiratory tract have been described in a previous publication by the author on the deposition of aerosol particles during normal breathing. However, an improved model of the respiratory tract, similar to a model suggested by Weibel, was employed. Comparison of the computer results with experiments was difficult, because of the absence of complete data in the literature. However, when estimates were made regarding the true experimental conditions under which certain results on smoke retention were obtained, a partial correlation was made possible by assuming a much larger mean particle size than is known to exist in raw smoke. The increase in mean particle size was tentatively ascribed to water absorption in the respiratory tract. Even with this assumption, the correlation was extremely poor at very low smoke inhalation volumes.The computer program analysis indicated that it should be possible to substantially reduce smoke deposition, without reducing smoke inhalation, by puffing on the cigarette at some point in the breathing cycle other than at the end of expiration, as is customary. This method of smoking was found to be as pleasurable as the normal method by most of the smokers who have used it.

scholarly journals Physical Properties of Tobacco Smoke Particles Produced under Different Conditions

1984 ◽  
Vol 12 (3) ◽  
Author(s):  
Y. Ishizu ◽  
K. Ohta ◽  
H. Tomita
Keyword(s):  
Weight Loss ◽  
Particle Size ◽  
Size Distribution ◽  
Tobacco Smoke ◽  
Mass Concentration ◽  
Inert Gas ◽  
Small Samples ◽  
Size Distributions ◽  
Heating Rates ◽  
Smoke Particles

AbstractSmall samples of tobacco powder, prepared by grinding the dried tobacco leaves, were heated in a micro-thermo-balance in different atmospheres and at different heating rates. The size distribution and the mass concentration of the smoke particles produced were measured simultaneously with a laser particle counter and a piezo balance mass monitor. In addition, the change of weight loss with time was also measured during each experiment. It was found that a larger amount of smoke particles was produced when tobacco was heated in the atmosphere of inert gas and/or at higher heating rates. Furthermore, comparison of measured and calculated size distributions showed that the particle size distribution was governed mainly by coagulation.

Study on the Influence of Air Tightness of the Building Envelope on Indoor Particle Concentration

2020 ◽  
Vol 12 (5) ◽  
pp. 1708 ◽  
Author(s):  
Liang Yu ◽  
Ning Kang ◽  
Weikuan Wang ◽  
Huiyu Guo ◽  
Jia Ji
Keyword(s):  
Particle Size ◽  
Particulate Matter ◽  
Mass Concentration ◽  
Penetration Rate ◽  
Particle Mass ◽  
Office Building ◽  
Measuring Point ◽  
Ratio Measurement ◽  
Air Tightness ◽  
Particle Mass Concentration

In order to grasp the building palisade structure tightness of indoor particulate matter mass concentration based on the particle penetration mechanism and settlement characteristics, this article analyzes the measurements of two different types of building air tightness of a Shenyang university office building in terms of indoor and outdoor particulate matter mass concentration levels from 2016-1-09 to 1-22, 2016-7-18 to 8-03, and 2017-2-28 to 3-13. The building outside the closed window that had no indoor source condition, the indoor office building and outdoor particle mass concentration, and the aperture size and shape of the envelope were analyzed to carry on the numerical simulation research by Fluent software, which was then analyzed; the results reveal that the measuring point of the I/O ratio is less than point B of the I/O ratio, measurement points of A linear regression fitting degree is lower than the fit of the measuring point B, and the causes for the measuring point A tightness (level 8) is superior to the measuring point B (level 4). When the gap height h is greater than 0.5 mm, the penetration rate of particles within the range of 0.25–2.5 μm particle size is close to 1. In different gap depths, the penetration rate of particles within the range of 0.1–1 μm particle size was close to 1. In diverse pressure difference, the 0.25–2.5 μm particles within the scope of penetration rate P is close to 1, the gap on both sides of the differential value ΔP; the greater the particle, the higher penetration rate. The larger the right-angle number of gap n, the lower the penetration rate of particles. The L-shaped gap and U-shaped gap have significantly better barrier effects in larger and smaller particles than the rectangular gap. The research results in this paper can help people understand and effectively control the influence of outdoor particles on the indoor air quality and provide reference data for the prediction of indoor particle mass concentration in buildings, which has theoretical basis and practical significance.

scholarly journals A New Angular Light Scattering Measurement of Particulate Matter Mass Concentration for Homogeneous Spherical Particles

Sensors ◽  
2019 ◽  
Vol 19 (10) ◽  
pp. 2243
Author(s):  
Dong Chen ◽  
Xiaowei Liu ◽  
Jinke Han ◽  
Meng Jiang ◽  
Zhaofeng Wang ◽  
...  
Keyword(s):  
Particle Size ◽  
Particulate Matter ◽  
Real Time ◽  
Mass Concentration ◽  
Power Plants ◽  
The Real ◽  
Particulate Matter Concentration ◽  
Matter Concentration ◽  
Fixed Detector ◽  
Measured Particle

Under the condition of ultra-low emission for power plants, the particulate matter concentration is significantly lower than that of typical power plants a decade ago, which posed new challenges for the particulate matter monitoring of stationary emission. The monitoring of particulate matter mass concentration based on ensemble light scattering has been found affected by particle size. Thus, this study develops a method of using the scattering angular distribution to obtain the real-time particle size, and then correct the particulate matter concentration with the real-time measured particle size. In this study, a real-time aerosol concentration and particle size measurement setup is constructed with a fixed detector at the forward direction and a rotating detector. The mass concentration is measured by the fixed detector, and the particle size is measured from the intensity ratio of the two detectors. The simulations show that the particle size has power law functionality with the angular spacing of the ripple structure according to Mie theory. Four quartz aerosols with different particle size are tested during the experiment, and the particle size measured from the ripple width is compared with the mass median size measured by an electrical low pressure impactor (ELPI). Both techniques have the same measurement tendency, and the measurement deviation by the ripple width method compared with ELPI is less than 15%. Finally, the measurement error of the real-time mass concentration is reduced from 38% to 18% with correction of the simultaneously measured particle size when particle size has changed.

PREDICTION OF AEROSOL PARTICLE SIZE DISTRIBUTION FROM THE MEAS-URED VALUES OF PM2.5 AND PM10

2021 ◽  
Author(s):  
A. Gilfanov ◽  
◽  
S. Zaripov ◽  
L. Fatkhutdinova ◽  
Keyword(s):  
Particle Size ◽  
Distribution Function ◽  
Particulate Matter ◽  
Respiratory Tract ◽  
Size Distribution ◽  
Aerosol Particles ◽  
Ambient Air ◽  
Size Distribution Function ◽  
Particle Dosimetry ◽  
Pm2.5 And Pm10

Abstract. Introduction. Ambient air pollution with particulate matter from various sources sig-nificantly increases the risk of human health disorders. The concentrations of the total suspended particles (TSP), as well as the PM2.5 and PM10 fractions, are mainly monitored. In fact, the ac-tual size distribution of aerosol particles differs significantly from the stepwise distribution formed only by the concentrations of PM2.5 and PM10. Aim of the study: development of a method for reconstructing the size distribution function of aerosol particles from the actual concentrations of PM2.5 and PM10 under the assumption of a lognormal size distribution for calculation of doses deposited in different lung regions. Methods. Long-term concentrations of various fractions of particles in the ambient air were ob-tained from the database of social and hygienic monitoring created by the "Center for Hygiene and Epidemiology in the Republic of Tatarstan (Tatarstan)". A reconstructed theoretical particle size distribution function f0(dp) was derived using the numerical solution, and the corresponding software was developed. The MPPD (Multiple-Path Particle Dosimetry) software was used to calculate the particle deposited doses in different areas of the human respiratory tract. Results. The measured values of the PM2.5 and PM10 concentrations were used to derive the lognormal aerosol size distribution. Based on the calculation of the mass doses of settled particles in the human respiratory system using MPPD (Multiple-Path Particle Dosimetry) code, it is shown that the calculation based only on the values of PM2.5 and PM10 leads to an underestimation of the mass fractions of particles in the lower respiratory tract and alveolar zone, the values of which are determinant for the estimation of the risk of lung disease. Conclusions. The proposed method for reconstructing the size distribution function of the con-centration of aerosol particles is important for a quantitatively reliable assessment of the risks of exposure to ambient air aerosols, making it possible to move from assessment of external expo-sures to the calculation of deposited fractions. The use of deposited fractions as an exposure pa-rameter increases the accuracy of health risk assessments associated with particulate matter ex-posure. This approach can be used both in the study of ambient aerosols and for the air of the working area.

scholarly journals FACTORS THAT AFFECT THE LUNG DEPOSITION

2013 ◽  
Vol 22 ◽  
pp. 729-732 ◽  
Author(s):  
SHWETA SANKHALA ◽  
H. S. SINGH ◽  
S. K. SINGH ◽  
GAUTAM LALWANI
Keyword(s):  
Particle Size ◽  
Respiratory Tract ◽  
Flow Rate ◽  
Lung Deposition ◽  
Inhaled Particles ◽  
Highly Effective

The lung is an external organ forming the site of unwanted material or particles. In order to protect it, the airways have to be highly effective filters and if the particle deposit they need to be cleared. Inhaled particles can cause a variety of diseases. There are various factors on which the prediction of depositing particles depends, such as age, particle size, flow rate gender, the physics of the particles, the anatomy of the respiratory tract etc.

Incorporation of micro/nanoparticles of PCL with essential oil of Cymbopogon nardus in bacterial cellulose

2018 ◽  
Vol 1 (2) ◽  
pp. 37
Author(s):  
Aline Krindges ◽  
Vanusca Dalosto Jahno ◽  
Fernando Morisso
Keyword(s):  
Particle Size ◽  
Particulate Matter ◽  
Essential Oil ◽  
Zeta Potential ◽  
Bacterial Cellulose ◽  
Culture Medium ◽  
Static Culture ◽  
Cymbopogon Nardus ◽  
Cellulose Membranes

Incorporation studies of particles in different substrates with herbal assets growing. The objective of this work was the preparation and characterization of micro/nanoparticles containing cymbopogon nardus essential oil; and the incorporation of them on bacterial cellulose. For the development of the membranes was used the static culture medium and for the preparation of micro/nanoparticles was used the nanoprecipitation methodology. The incorporation of micro/nanoparticles was performed on samples of bacterial cellulose in wet and dry form. For the characterization of micro/nanoparticles were carried out analysis of SEM, zeta potential and particle size. For the verification of the incorporation of particulate matter in cellulose, analyses were conducted of SEM and FTIR. The results showed that it is possible the production and incorporation of micro/nanoparticles containing essential oil in bacterial cellulose membranes in wet form with ethanol.

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