The Effect of Ventilation, Age, and Asthmatic Condition on Ultrafine Particle Deposition in Children

Ultrafine particles (UFPs) contribute to health risks associated with air pollution, especially respiratory disease in children. Nonetheless, experimental data on UFP deposition in asthmatic children has been minimal. In this study, the effect of ventilation, developing respiratory physiology, and asthmatic condition on the deposition efficiency of ultrafine particles in children was explored. Deposited fractions of UFP (10–200 nm) were determined in 9 asthmatic children, 8 nonasthmatic children, and 5 nonasthmatic adults. Deposition efficiencies in adults served as reference of fully developed respiratory physiologies. A validated deposition model was employed as an auxiliary tool to assess the independent effect of varying ventilation on deposition. Asthmatic conditions were confirmed via pre-and post-bronchodilator spirometry. Subjects were exposed to a hygroscopic aerosol with number geometric mean diameter of 27–31 nm, geometric standard deviation of 1.8–2.0, and concentration of1.2×106particles cm−3. Exposure was through a silicone mouthpiece. Total deposited fraction (TDF) and normalized deposition rate were 50% and 32% higher in children than in adults. Accounting for tidal volume and age variation, TDF was 21% higher in asthmatic than in non-asthmatic children. The higher health risks of air pollution exposure observed in children and asthmatics might be augmented by their susceptibility to higher dosages of UFP.

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Indoor air pollution exposures and cardiometabolic health across four diverse settings in Peru: a cross-sectional study

10.21203/rs.2.21075/v1 ◽

2020 ◽

Author(s):

Josiah L Kephart ◽

Magdalena Fandiño-Del-Rio ◽

Kirsten Koehler ◽

Antonio Bernabe-Ortiz ◽

J Jaime Miranda ◽

...

Keyword(s):

Air Pollution ◽

Carbon Monoxide ◽

Standard Deviation ◽

Indoor Air ◽

Indoor Air Pollution ◽

Geometric Mean ◽

Geometric Standard Deviation ◽

Pm 2.5 ◽

Daily Average ◽

Co Concentrations

Abstract Background Indoor air pollution is an important risk factor for health in low- and middle-income countries. Methods We measured indoor fine particulate matter (PM 2.5 ) and carbon monoxide (CO) concentrations in 617 houses across four settings with varying urbanisation, altitude, and biomass cookstove use in Peru, between 2010 and 2016. We assessed the associations between indoor pollutant concentrations and blood pressure (BP), exhaled carbon monoxide (eCO), C-reactive protein (CRP), and haemoglobin A1c (HbA1c) using multivariable linear regression. Results We found high concentrations of indoor PM 2.5 across all four settings (geometric mean ± geometric standard deviation of PM 2.5 daily average in µg/m 3 ): Lima 41.1 ± 1.3, Tumbes 35.8 ± 1.4, urban Puno 14.1 ± 1.7, and rural Puno 58.8 ± 3.1. High indoor CO concentrations were common in rural households (geometric mean ± geometric standard deviation of CO daily average in ppm): rural Puno 4.9 ± 4.3. Higher indoor PM 2.5 was associated with having a higher systolic BP (1.51 mmHg per interquartile range (IQR) increase, 95% CI 0.16 to 2.86), a higher diastolic BP (1.39 mmHg higher DBP per IQR increase, 95% CI 0.52 to 2.25), and a higher eCO (2.05 ppm higher per IQR increase, 95% CI 0.52 to 3.57). There was no evidence of associations between indoor air exposures and CRP or HbA1c outcomes. Conclusions Excessive indoor concentrations of PM 2.5 are widespread across varying levels of urbanisation, altitude, and biomass cookstove use in Peru and are associated with worse BP and higher eCO.

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Potential pathophysiological mechanisms of ultrafine particle toxic effects in humans

Chemical Industry and Chemical Engineering Quarterly ◽

10.2298/ciceq0801047j ◽

2008 ◽

Vol 14 (1) ◽

pp. 47-49 ◽

Cited By ~ 1

Author(s):

Jasmina Jovic-Stosic ◽

Milena Jovasevic-Stojanovic

Keyword(s):

Air Pollution ◽

Cardiovascular Diseases ◽

Ultrafine Particles ◽

Biological Effects ◽

Ultrafine Particle ◽

Great Influence ◽

Ambient Air ◽

Biologically Active ◽

Ambient Air Pollution ◽

General Hypothesis

Epidemiological and clinical studies suggested the association of the particulate matter ambient air pollution and the increased morbidity and mortality, mainly from respiratory and cardiovascular diseases. The size of particles has great influence on their toxicity, because it determines the site in the respiratory tract where they deposit. The most well established theory explaining the mechanisms behind the increased toxicity of ultrafine particles (UFP, < 0.1 ?m) is that it has to do with the increased surface area and/or the combination with the increased number of particles. Biological effects of UFP are also determined by their shape and chemical composition, so it is not possible to estimate their toxicity in a general way. General hypothesis suggested that exposure to inhaled particles induces pulmonary alveolar inflammation as a basic pathophysiological event, triggering release of various proinflammatory cytokines. Chronic inflammation is a very important underlying mechanism in the genesis of atherosclerosis and cardiovascular diseases. UFP can freely move through the circulation, but their effects on the secondary organs are not known yet, so more studies on recognizing toxicological endpoints of UFP are needed. Determination of UFP toxicity and the estimation of their internal and biologically active dose are necessary for the evidence based conclusions connecting air pollution by UFP and human diseases. .

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Efficiency of cloud condensation nuclei formation from ultrafine particles

Atmospheric Chemistry and Physics ◽

10.5194/acp-7-1367-2007 ◽

2007 ◽

Vol 7 (5) ◽

pp. 1367-1379 ◽

Cited By ~ 143

Author(s):

J. R. Pierce ◽

P. J. Adams

Keyword(s):

Size Distribution ◽

Ultrafine Particles ◽

Particle Deposition ◽

Cloud Condensation Nuclei ◽

Large Fraction ◽

Ultrafine Particle ◽

Aerosol Size Distribution ◽

Condensation Nuclei ◽

Anthropogenic Aerosol ◽

Different Parts

Abstract. Atmospheric cloud condensation nuclei (CCN) concentrations are a key uncertainty in the assessment of the effect of anthropogenic aerosol on clouds and climate. The ability of new ultrafine particles to grow to become CCN varies throughout the atmosphere and must be understood in order to understand CCN formation. We have developed the Probability of Ultrafine particle Growth (PUG) model to answer questions regarding which growth and sink mechanisms control this growth, how the growth varies between different parts of the atmosphere and how uncertainties with respect to the magnitude and size distribution of ultrafine emissions translates into uncertainty in CCN generation. The inputs to the PUG model are the concentrations of condensable gases, the size distribution of ambient aerosol, particle deposition timescales and physical properties of the particles and condensable gases. It was found in most cases that condensation is the dominant growth mechanism and coagulation with larger particles is the dominant sink mechanism for ultrafine particles. In this work we found that the probability of a new ultrafine particle generating a CCN varies from <0.1% to ~90% in different parts of the atmosphere, though in the boundary layer a large fraction of ultrafine particles have a probability between 1% and 40%. Some regions, such as the tropical free troposphere, are areas with high probabilities; however, variability within regions makes it difficult to predict which regions of the atmosphere are most efficient for generating CCN from ultrafine particles. For a given mass of primary ultrafine aerosol, an uncertainty of a factor of two in the modal diameter can lead to an uncertainty in the number of CCN generated as high as a factor for eight. It was found that no single moment of the primary aerosol size distribution, such as total mass or number, is a robust predictor of the number of CCN ultimately generated. Therefore, a complete description of the emissions size distribution is generally required for global aerosol microphysics models.

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COVID-19 Immunopathology, Particle Pollution, and Iron Balance

Journal of Advances in Medicine and Medical Research ◽

10.9734/jammr/2020/v32i1830654 ◽

2020 ◽

pp. 43-60

Author(s):

Mark Whiteside ◽

J. Marvin Herndon

Keyword(s):

Climate Change ◽

Air Pollution ◽

Ultrafine Particles ◽

Coal Fly Ash ◽

Ultrafine Particle ◽

Noncommunicable Disease ◽

Noncommunicable Diseases ◽

Monitoring And Control ◽

Tropospheric Aerosol ◽

Iron Dysregulation

The coronavirus (COVID-19) pandemic exploded into a world already reeling from climate change, degradation of natural systems, and pandemics of air pollution and noncommunicable diseases. These pandemics are interrelated; air pollution, the world’s biggest killer, is a major contributor to noncommunicable disease. Air pollution is a probable cofactor in the spread and severity of COVID-19. There are shared mechanisms of injury by the emerging COVID-19 immunopathology, ultrafine air pollutants, and chronic degenerative disease. A key feature of each is oxidative stress, including that caused by iron dysregulation. Exogenous combustion-derived magnetite nanoparticles found in human brains and hearts are strongly implicated in the development of cardiometabolic and neurogenerative disease. Altered iron balance favoring excess reactive or misplaced iron is probably the most important predisposing condition for severe COVID-19 infection. Ultrafine-particle/nanoparticle toxicity and COVID-19 immunopathology on the subcellular level are both characterized by iron dysregulation, mitochondrial dysfunction, and endoplasmic reticulum stress. Primary sources of the most damaging ultrafine pollution particles are fossil fuel combustion, vehicle emissions, and coal fly ash utilized in undisclosed tropospheric aerosol geoengineering. The same ultrafine particles when emitted or placed into the troposphere alter the world’s cloud layers and reduce atmospheric convection, directly contributing to climate change and global warming. Pandemics can only be tackled by international cooperation. Immediate steps that must be taken include monitoring and control of ultrafine particulate air pollution, and prompt cessation of geoengineering operations.

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Indoor air pollution concentrations and cardiometabolic health across four diverse settings in Peru: a cross-sectional study

10.21203/rs.2.21075/v2 ◽

2020 ◽

Author(s):

Josiah L Kephart ◽

Magdalena Fandiño-Del-Rio ◽

Kirsten Koehler ◽

Antonio Bernabe-Ortiz ◽

J Jaime Miranda ◽

...

Keyword(s):

Air Pollution ◽

Carbon Monoxide ◽

Standard Deviation ◽

Indoor Air ◽

Indoor Air Pollution ◽

Geometric Mean ◽

Geometric Standard Deviation ◽

Pm 2.5 ◽

Daily Average ◽

Co Concentrations

Abstract Background: Indoor air pollution is an important risk factor for health in low- and middle-income countries. Methods: We measured indoor fine particulate matter (PM 2.5 ) and carbon monoxide (CO) concentrations in 617 houses across four settings with varying urbanisation, altitude, and biomass cookstove use in Peru, between 2010 and 2016. We assessed the associations between indoor pollutant concentrations and blood pressure (BP), exhaled carbon monoxide (eCO), C-reactive protein (CRP), and haemoglobin A1c (HbA1c) using multivariable linear regression among all participants and stratifying by use of biomass cookstoves. Results: We found high concentrations of indoor PM 2.5 across all four settings (geometric mean ± geometric standard deviation of PM 2.5 daily average in µg/m 3 ): Lima 41.1 ± 1.3, Tumbes 35.8 ± 1.4, urban Puno 14.1 ± 1.7, and rural Puno 58.8 ± 3.1. High indoor CO concentrations were common in rural households (geometric mean ± geometric standard deviation of CO daily average in ppm): rural Puno 4.9 ± 4.3. Higher indoor PM 2.5 was associated with having a higher systolic BP (1.51 mmHg per interquartile range (IQR) increase, 95% CI 0.16 to 2.86), a higher diastolic BP (1.39 mmHg higher DBP per IQR increase, 95% CI 0.52 to 2.25), and a higher eCO (2.05 ppm higher per IQR increase, 95% CI 0.52 to 3.57). When stratifying by biomass cookstove use, our results were consistent with effect measure modification in the association between PM 2.5 and eCO: among biomass users eCO was 0.20 ppm higher per IQR increase in PM 2.5 (95% CI -2.05 to 2.46), and among non-biomass users eCO was 5.00 ppm higher per IQR increase in PM 2.5 (95% CI 1.58 to 8.41). We did not find associations between indoor air concentrations and CRP or HbA1c outcomes. Conclusions: Excessive indoor concentrations of PM 2.5 are widespread in homes across varying levels of urbanisation, altitude, and biomass cookstove use in Peru and are associated with worse BP and higher eCO.

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Exposure Characterization of Ultrafine Particles From the Blast Furnace Process in a Steelmaking Plant

10.21203/rs.3.rs-54690/v1 ◽

2020 ◽

Author(s):

Xiangjing Gao ◽

Hua Zou ◽

Qunli Wang ◽

Zanrong Zhou ◽

Weiming Yuan ◽

...

Keyword(s):

Blast Furnace ◽

Ultrafine Particles ◽

Geometric Mean ◽

Ultrafine Particle ◽

Correlation Coefficients ◽

Personal Exposure ◽

Temporal Variations ◽

Exposure Level ◽

Blast Furnace Process ◽

Furnace Process

Abstract Background: Information regarding the exposure characteristics of ultrafine particles generated by working activities in the steelmaking industry is very limited. This study aimed to investigate the exposure characteristics of ultrafine particles from the blast furnace process in a steelmaking industry. Methods: The morphology of particles, their elemental compositions, temporal variations in particle concentrations (e.g., total number concentration (NC), total respirable mass concentration (MC), surface area concentration (SAC)), personal exposure level, and the size distributions by number were measured. The relationships among total NC, total respirable MC, and SAC were determined by analyzing the concentration ratios (CR), correlation coefficients (CC), and the consistency of temporal variations in particle concentrations. Results: The particles collected from the blast furnace process presented as irregular agglomerates, and the predominant elements were O, Al, and Si. The total NC, total respirable MC, and SAC increased after working activity started and decreased gradually to background levels after the operation stopped. The median, mean, geometric mean, and modal sizes of particles remained relatively stable during working activities, ranging from 20 to 50 nm. Size distribution by number showed that the sizes of particles released from the slag releasing location were mainly gathered at 10.4 and 40 nm. The highest numbers appeared at 10.4 nm and 40 nm, which reached 3 × 106 pt/cm3. Particles ranging 100–469 nm were less than 8 × 105 pt/cm3, while particles with sizes larger than 374 nm were less than 2 × 104 pt/cm3. There was a good correlation between the total NC, SAC, and respirable MC. The order of CC for these three parameters was R total NC and SAC (r = 0.681) > R SAC and respirable MC (0.456) > R total NC and respirable MC (0.424).Conclusions: These findings indicate that working activities generated high levels of ultrafine particles. The ultrafine particle concentrations exhibited activity-related and periodic variations. The total NC and SAC were more appropriate metrics for characterizing ultrafine particles at the slag releasing location than total respirable MC. This study provides baseline data on the exposure characteristics of ultrafine particles during the blast furnace process.

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Impact on Ultrafine Particles Concentration and Turbulent Fluxes of SARS-CoV-2 Lockdown in a Suburban Area in Italy

Atmosphere ◽

10.3390/atmos12030407 ◽

2021 ◽

Vol 12 (3) ◽

pp. 407

Author(s):

Antonio Donateo ◽

Adelaide Dinoi ◽

Gianluca Pappaccogli

Keyword(s):

Ultrafine Particles ◽

Particle Number ◽

Ultrafine Particle ◽

Turbulent Fluxes ◽

Number Concentration ◽

Suburban Area ◽

Observation Site ◽

Meteorological Forcing ◽

Restrictive Measures ◽

Measurement Area

In order to slow the spread of SARS-CoV-2, governments have implemented several restrictive measures (lockdown, stay-in-place, and quarantine policies). These provisions have drastically changed the routines of residents, altering environmental conditions in the affected areas. In this context, our work analyzes the effects of the reduced emissions during the COVID-19 period on the ultrafine particles number concentration and their turbulent fluxes in a suburban area. COVID-19 restrictions did not significantly reduce anthropogenic related PM10 and PM2.5 levels, with an equal decrement of about 14%. The ultrafine particle number concentration during the lockdown period decreased by 64% in our measurement area, essentially due to the lower traffic activity. The effect of the restriction measures and the reduction of vehicles traffic was predominant in reducing concentration rather than meteorological forcing. During the lockdown in 2020, a decrease of 61% in ultrafine particle positive fluxes can be observed. At the same time, negative fluxes decreased by 59% and our observation site behaved, essentially, as a sink of ultrafine particles. Due to this behavior, we can conclude that the principal particle sources during the lockdown were far away from the measurement site.

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Health Impacts of Urban Bicycling in Mexico

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18052300 ◽

2021 ◽

Vol 18 (5) ◽

pp. 2300

Author(s):

David Rojas-Rueda

Keyword(s):

Public Health ◽

Physical Activity ◽

Air Pollution ◽

Health Risks ◽

Health Benefits ◽

Health Impacts ◽

Traffic Fatalities ◽

Premature Deaths ◽

Air Pollution Exposure ◽

Pollution Exposure

Background: Bicycling has been associated with health benefits. Local and national authorities have been promoting bicycling as a tool to improve public health and the environment. Mexico is one of the largest Latin American countries, with high levels of sedentarism and non-communicable diseases. No previous studies have estimated the health impacts of Mexico’s national bicycling scenarios. Aim: Quantify the health impacts of Mexico urban bicycling scenarios. Methodology: Quantitative Health Impact Assessment, estimating health risks and benefits of bicycling scenarios in 51,718,756 adult urban inhabitants in Mexico (between 20 and 64 years old). Five bike scenarios were created based on current bike trends in Mexico. The number of premature deaths (increased or reduced) was estimated in relation to physical activity, road traffic fatalities, and air pollution. Input data were collected from national publicly available data sources from transport, environment, health and population reports, and surveys, in addition to scientific literature. Results: We estimated that nine premature deaths are prevented each year among urban populations in Mexico on the current car-bike substitution and trip levels (1% of bike trips), with an annual health economic benefit of US $1,897,920. If Mexico achieves similar trip levels to those reported in The Netherlands (27% of bike trips), 217 premature deaths could be saved annually, with an economic impact of US $45,760,960. In all bicycling scenarios assessed in Mexico, physical activity’s health benefits outweighed the health risks related to traffic fatalities and air pollution exposure. Conclusion: The study found that bicycling promotion in Mexico would provide important health benefits. The benefits of physical activity outweigh the risk from traffic fatalities and air pollution exposure in bicyclists. At the national level, Mexico could consider using sustainable transport policies as a tool to promote public health. Specifically, the support of active transportation through bicycling and urban design improvements could encourage physical activity and its health co-benefits.

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Introduction to Special Issue on Air Pollution Health Risks

Risk Analysis ◽

10.1111/risa.12707 ◽

2016 ◽

Vol 36 (9) ◽

pp. 1688-1692 ◽

Cited By ~ 6

Author(s):

D. Warner North

Keyword(s):

Air Pollution ◽

Health Risks ◽

Special Issue

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The Variation of Riverbed Material due to Tropical Storms in Shi-Wen River, Taiwan

The Scientific World JOURNAL ◽

10.1155/2014/580936 ◽

2014 ◽

Vol 2014 ◽

pp. 1-12

Author(s):

Chin-Ping Lin ◽

Yu-Min Wang ◽

Samkele S. Tfwala ◽

Ching-Nuo Chen

Keyword(s):

Grain Size ◽

Geometric Mean ◽

Size Variation ◽

Annual Rainfall ◽

Geometric Standard Deviation ◽

Roughness Coefficient ◽

Bed Form ◽

Subsurface Material ◽

Typhoon Season ◽

Bed Material

Taiwan, because of its location, is a flood prone region and is characterised by typhoons which brings about two-thirds to three quarters of the annual rainfall amount. Consequently, enormous flows result in rivers and entrain some fractions of the grains that constitute the riverbed. Hence, the purpose of the study is to quantify the impacts of these enormous flows on the distribution of grain size in riverbeds. The characteristics of riverbed material prior to and after the typhoon season are compared in Shi-Wen River located at southern Taiwan. These include grain size variation, bimodality, and roughness coefficient. A decrease (65%) and increase (50%) in geometric mean size of grains were observed for subsurface and surface bed material, respectively. Geometric standard deviation decreased in all sites after typhoon. Subsurface material was bimodal prior to typhoons and polymodal after. For surface material, modal class is in the gravel class, while after typhoons it shifts towards cobble class. The reduction in geometric mean resulted to a decrease in roughness coefficient by up to 30%. Finally, the relationship of Shields and Froude numbers are studied and a change in the bed form to antidunes and transition form is observed, respectively.

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