Particulate matter (PM) describes airborne materials that come from both natural and human-made sources. PM is regulated because it poses risks to human health, including premature death and cardiovascular and respiratory diseases. The risks depend on particle size, with smaller particles posing greater risks as they can penetrate deeper into the lungs. Early studies of severe air pollution episodes provided evidence of links between PM exposure and health impacts. Later epidemiological studies using more rigorous methods strengthened the evidence of causal relationships and helped identify susceptible populations. Ongoing research continues to improve understanding of health risks from PM exposure and inform regulatory standards.
A national study on long-term exposure to air pollution to human health and correlation to COVID-19 mortality - pollution kills and every 1ug/m3 PM 2.5 increases the death rate from COVID by 15%.
A national study on long-term exposure to air pollution to human health and correlation to COVID-19 mortality - pollution kills and every 1ug/m3 PM 2.5 increases the death rate from COVID by 15%.
Air pollution is a familiar environmental health hazard. We know what we’re looking at
when brown haze settles over a city, exhaust billows across a busy highway, or a plume
rises from a smokestack. Some air pollution is not seen, but its pungent smell alerts you.
It is a major threat to global health and prosperity. Air pollution, in all forms, is responsible
for more than 6.5 million deaths each year globally, a number that has increased over the
past two decades.
Air pollution is a mix of hazardous substances from both human-made and natural sources.
Vehicle emissions, fuel oils and natural gas to heat homes, by-products of manufacturing
and power generation, particularly coal-fueled power plants, and fumes from chemical
production are the primary sources of human-made air pollution.
Nature releases hazardous substances into the air, such as smoke from wildfires, which are
often caused by people; ash and gases from volcanic eruptions; and gases, like methane,
which are emitted from decomposing organic matter in soils.
Running head AIR POLLUTION BY HAZE 1AIR POLLUTION BY HAZE 1.docxtoddr4
Running head: AIR POLLUTION BY HAZE 1
AIR POLLUTION BY HAZE 1
Air Pollution by Haze
Student’s Name
Instructor’s Name
Date
Abstract
Air pollution is a critical problem of the modern world, which has posed dangerous toxicological effects to the environment and human health. Haze is among the most significant pollutants of the new civilized world. Haze originates from various emissions; however, industrial processes and vehicular emissions contribute to significant factors that lead to the formation of haze. As documented by the World Health Organization, six principal air contaminants include ground-level ozone, lead, nitrogen oxides, carbon monoxides, and Sulphur dioxide. Continuous exposure to factors that contribute to the formation of haze promote various toxicological effects on human life such as cardiovascular as well as respiratory ailments, irritation of the eyes, long term chronic ailments like cancer, and neuropsychiatric issues. Air pollution by haze is reported to be a major environmental threat in the progression and incidence of some health complications such as low birth weight, asthma, Alzheimer and Parkinson’ diseases, lung cancer, autism, fetal growth, psychological problems, and ventricular hypertrophy. In this research paper, major causes of pollution by haze are discussed, emission sources and subsequent effects on human wellbeing.
Air Pollution by Haze
The social and economic activities of densely populated areas release large volumes of fine particulate matters. While these fine particulate materials unendingly pile beyond the ability of atmospheric self-cleaning to eradicate it, the haze weather is created. Haze weather is usually a mixture of the effects of stable and static weather. Current scientific studies conducted mostly in western Europe and North America demonstrate that air pollution in urban areas as a result of haze is triggering numerous health issues from eye itching to death. Increase in the speed for urbanization and industrialization in major cities of the world has led to growth in the badness of urban air pollution. “Amounts of fine particles are usually in thousands of micrograms in cubic meter across many cities of the world that are going through modern industrialization” (Astrobum, Apr 30 2017). Grievous installments of air pollution have wrapped a better part of the world. By November 2015, for instance, in China, the cities located to the northern area of the country have recently experienced high levels of haze due to the rise in particulate matter. The particulate matter increased from 360 to 700 µg/m3 up to 28 times much above the levels recommended by the world health organization (WHO).
Exposure to particulate matter has often been linked with numerous health problems; however, issues related to mortality are undeniably the most important to address since they are also among the prevalently amenable issues to the assessment of the world. Most epidemiological da.
Assess and Forecast Air Pollution Using Environmental APIsAmbee
With the advancement of air pollution management and research since the 1960s, it has become more important for people to
understand the impact of pollen API and environmental API. The Ambee Pollen API makes it easy for customers to generate data
with just a few clicks.
Developing World and Occupational Health ImpactsAI Publications
The environment is an integral part of human life the quality of which plays a critical role in human health. Occupational environment presents potential health hazards to workers employed in a variety of positions. This review adds to a growing body of evidence that PM is really harmful to health increasing overall mortality mostly deaths from cardiovascular disease as well as deaths from respiratory diseases.
Environmental health Effect and Air Pollution from cigarette smokers in Cross...IOSR Journals
This study is aimed at assessing the cause of air pollution and Environmental health effect on people living in Cross River State using cigarette smokers as a case study. Data was gathered through a well designed and articulated oral and written questionnaires, direct and first-hand observation of the environment, and comprehensive interview sessions were carried out with community Heads (Royal Authorities where possible), patients and youths. A total of one hundred and seventeen thousand (117,000) questionnaires were randomly distributed evenly to men of about 20-75years old in all the Eighteen (18) Local Government Area in Cross River State. Eighty seven thousand, five hundred and thirty three (87,533) valid questionnaire were received back. Nine hundred (900) of the people reported that they do not smoke any cigarette. Table 1 shows the total number of people who smoke cigarette. Table 2a,b show the total number of patients with smoking related diseases. Most of these patients with smoking related diseases such as decrease in lung function, increase of heart attack, Respiratory diseases, cancer, asthma, and other health effects are having those disease conditions as a result of their smoking habits.
Case studies in improving urban air qualityngocjos
IGU study finds that the switch to natural gas helps mega-cities dramatically improve air quality and reduce emissions of GHG and air pollutants – enhancing and saving lives. On the sidelines of the COP21 negotiations in Paris the IGU has released a major study that highlights the interconnection that exists between reducing greenhouse gas emissions and reducing emissions of other air pollutants. It presents case studies of efforts in four cities — New York, Istanbul, Toronto, and Beijing — that have tackled or are tackling the issue of improving urban air quality and where gas has featured as the main contributor to their efforts. These cities can provide lessons for other cities seeking to reduce the potentially severe health consequences of urban air pollution.
Many forms of atmospheric pollution affect human health
and the environment at levels from local to global. These
contaminants are emitted from diverse sources, and some
of them react together to form new compounds in the air.
Industrialized nations have made important progress toward controlling some pollutants in recent decades, but air quality is much worse in many developing countries, and global circulation patterns can transport some types of pollution rapidly around the world. In this unit, discover the basic chemistry of atmospheric pollution and learn which human activities have the greatest impacts on air quality.
Why Do People Get Sick in Damp Buildings? The joint conference of the Wisconsin Environmental Health Association and the Bureau of Environmental and Occupational Health (Wisconsin Department of Health Services).
Epcon is One of the World's leading Manufacturing Companies.EpconLP
Epcon is One of the World's leading Manufacturing Companies. With over 4000 installations worldwide, EPCON has been pioneering new techniques since 1977 that have become industry standards now. Founded in 1977, Epcon has grown from a one-man operation to a global leader in developing and manufacturing innovative air pollution control technology and industrial heating equipment.
Climate Change All over the World .pptxsairaanwer024
Climate change refers to significant and lasting changes in the average weather patterns over periods ranging from decades to millions of years. It encompasses both global warming driven by human emissions of greenhouse gases and the resulting large-scale shifts in weather patterns. While climate change is a natural phenomenon, human activities, particularly since the Industrial Revolution, have accelerated its pace and intensity
Air pollution is a familiar environmental health hazard. We know what we’re looking at
when brown haze settles over a city, exhaust billows across a busy highway, or a plume
rises from a smokestack. Some air pollution is not seen, but its pungent smell alerts you.
It is a major threat to global health and prosperity. Air pollution, in all forms, is responsible
for more than 6.5 million deaths each year globally, a number that has increased over the
past two decades.
Air pollution is a mix of hazardous substances from both human-made and natural sources.
Vehicle emissions, fuel oils and natural gas to heat homes, by-products of manufacturing
and power generation, particularly coal-fueled power plants, and fumes from chemical
production are the primary sources of human-made air pollution.
Nature releases hazardous substances into the air, such as smoke from wildfires, which are
often caused by people; ash and gases from volcanic eruptions; and gases, like methane,
which are emitted from decomposing organic matter in soils.
Running head AIR POLLUTION BY HAZE 1AIR POLLUTION BY HAZE 1.docxtoddr4
Running head: AIR POLLUTION BY HAZE 1
AIR POLLUTION BY HAZE 1
Air Pollution by Haze
Student’s Name
Instructor’s Name
Date
Abstract
Air pollution is a critical problem of the modern world, which has posed dangerous toxicological effects to the environment and human health. Haze is among the most significant pollutants of the new civilized world. Haze originates from various emissions; however, industrial processes and vehicular emissions contribute to significant factors that lead to the formation of haze. As documented by the World Health Organization, six principal air contaminants include ground-level ozone, lead, nitrogen oxides, carbon monoxides, and Sulphur dioxide. Continuous exposure to factors that contribute to the formation of haze promote various toxicological effects on human life such as cardiovascular as well as respiratory ailments, irritation of the eyes, long term chronic ailments like cancer, and neuropsychiatric issues. Air pollution by haze is reported to be a major environmental threat in the progression and incidence of some health complications such as low birth weight, asthma, Alzheimer and Parkinson’ diseases, lung cancer, autism, fetal growth, psychological problems, and ventricular hypertrophy. In this research paper, major causes of pollution by haze are discussed, emission sources and subsequent effects on human wellbeing.
Air Pollution by Haze
The social and economic activities of densely populated areas release large volumes of fine particulate matters. While these fine particulate materials unendingly pile beyond the ability of atmospheric self-cleaning to eradicate it, the haze weather is created. Haze weather is usually a mixture of the effects of stable and static weather. Current scientific studies conducted mostly in western Europe and North America demonstrate that air pollution in urban areas as a result of haze is triggering numerous health issues from eye itching to death. Increase in the speed for urbanization and industrialization in major cities of the world has led to growth in the badness of urban air pollution. “Amounts of fine particles are usually in thousands of micrograms in cubic meter across many cities of the world that are going through modern industrialization” (Astrobum, Apr 30 2017). Grievous installments of air pollution have wrapped a better part of the world. By November 2015, for instance, in China, the cities located to the northern area of the country have recently experienced high levels of haze due to the rise in particulate matter. The particulate matter increased from 360 to 700 µg/m3 up to 28 times much above the levels recommended by the world health organization (WHO).
Exposure to particulate matter has often been linked with numerous health problems; however, issues related to mortality are undeniably the most important to address since they are also among the prevalently amenable issues to the assessment of the world. Most epidemiological da.
Assess and Forecast Air Pollution Using Environmental APIsAmbee
With the advancement of air pollution management and research since the 1960s, it has become more important for people to
understand the impact of pollen API and environmental API. The Ambee Pollen API makes it easy for customers to generate data
with just a few clicks.
Developing World and Occupational Health ImpactsAI Publications
The environment is an integral part of human life the quality of which plays a critical role in human health. Occupational environment presents potential health hazards to workers employed in a variety of positions. This review adds to a growing body of evidence that PM is really harmful to health increasing overall mortality mostly deaths from cardiovascular disease as well as deaths from respiratory diseases.
Environmental health Effect and Air Pollution from cigarette smokers in Cross...IOSR Journals
This study is aimed at assessing the cause of air pollution and Environmental health effect on people living in Cross River State using cigarette smokers as a case study. Data was gathered through a well designed and articulated oral and written questionnaires, direct and first-hand observation of the environment, and comprehensive interview sessions were carried out with community Heads (Royal Authorities where possible), patients and youths. A total of one hundred and seventeen thousand (117,000) questionnaires were randomly distributed evenly to men of about 20-75years old in all the Eighteen (18) Local Government Area in Cross River State. Eighty seven thousand, five hundred and thirty three (87,533) valid questionnaire were received back. Nine hundred (900) of the people reported that they do not smoke any cigarette. Table 1 shows the total number of people who smoke cigarette. Table 2a,b show the total number of patients with smoking related diseases. Most of these patients with smoking related diseases such as decrease in lung function, increase of heart attack, Respiratory diseases, cancer, asthma, and other health effects are having those disease conditions as a result of their smoking habits.
Case studies in improving urban air qualityngocjos
IGU study finds that the switch to natural gas helps mega-cities dramatically improve air quality and reduce emissions of GHG and air pollutants – enhancing and saving lives. On the sidelines of the COP21 negotiations in Paris the IGU has released a major study that highlights the interconnection that exists between reducing greenhouse gas emissions and reducing emissions of other air pollutants. It presents case studies of efforts in four cities — New York, Istanbul, Toronto, and Beijing — that have tackled or are tackling the issue of improving urban air quality and where gas has featured as the main contributor to their efforts. These cities can provide lessons for other cities seeking to reduce the potentially severe health consequences of urban air pollution.
Many forms of atmospheric pollution affect human health
and the environment at levels from local to global. These
contaminants are emitted from diverse sources, and some
of them react together to form new compounds in the air.
Industrialized nations have made important progress toward controlling some pollutants in recent decades, but air quality is much worse in many developing countries, and global circulation patterns can transport some types of pollution rapidly around the world. In this unit, discover the basic chemistry of atmospheric pollution and learn which human activities have the greatest impacts on air quality.
Why Do People Get Sick in Damp Buildings? The joint conference of the Wisconsin Environmental Health Association and the Bureau of Environmental and Occupational Health (Wisconsin Department of Health Services).
Epcon is One of the World's leading Manufacturing Companies.EpconLP
Epcon is One of the World's leading Manufacturing Companies. With over 4000 installations worldwide, EPCON has been pioneering new techniques since 1977 that have become industry standards now. Founded in 1977, Epcon has grown from a one-man operation to a global leader in developing and manufacturing innovative air pollution control technology and industrial heating equipment.
Climate Change All over the World .pptxsairaanwer024
Climate change refers to significant and lasting changes in the average weather patterns over periods ranging from decades to millions of years. It encompasses both global warming driven by human emissions of greenhouse gases and the resulting large-scale shifts in weather patterns. While climate change is a natural phenomenon, human activities, particularly since the Industrial Revolution, have accelerated its pace and intensity
Willie Nelson Net Worth: A Journey Through Music, Movies, and Business Venturesgreendigital
Willie Nelson is a name that resonates within the world of music and entertainment. Known for his unique voice, and masterful guitar skills. and an extraordinary career spanning several decades. Nelson has become a legend in the country music scene. But, his influence extends far beyond the realm of music. with ventures in acting, writing, activism, and business. This comprehensive article delves into Willie Nelson net worth. exploring the various facets of his career that have contributed to his large fortune.
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Introduction
Willie Nelson net worth is a testament to his enduring influence and success in many fields. Born on April 29, 1933, in Abbott, Texas. Nelson's journey from a humble beginning to becoming one of the most iconic figures in American music is nothing short of inspirational. His net worth, which estimated to be around $25 million as of 2024. reflects a career that is as diverse as it is prolific.
Early Life and Musical Beginnings
Humble Origins
Willie Hugh Nelson was born during the Great Depression. a time of significant economic hardship in the United States. Raised by his grandparents. Nelson found solace and inspiration in music from an early age. His grandmother taught him to play the guitar. setting the stage for what would become an illustrious career.
First Steps in Music
Nelson's initial foray into the music industry was fraught with challenges. He moved to Nashville, Tennessee, to pursue his dreams, but success did not come . Working as a songwriter, Nelson penned hits for other artists. which helped him gain a foothold in the competitive music scene. His songwriting skills contributed to his early earnings. laying the foundation for his net worth.
Rise to Stardom
Breakthrough Albums
The 1970s marked a turning point in Willie Nelson's career. His albums "Shotgun Willie" (1973), "Red Headed Stranger" (1975). and "Stardust" (1978) received critical acclaim and commercial success. These albums not only solidified his position in the country music genre. but also introduced his music to a broader audience. The success of these albums played a crucial role in boosting Willie Nelson net worth.
Iconic Songs
Willie Nelson net worth is also attributed to his extensive catalog of hit songs. Tracks like "Blue Eyes Crying in the Rain," "On the Road Again," and "Always on My Mind" have become timeless classics. These songs have not only earned Nelson large royalties but have also ensured his continued relevance in the music industry.
Acting and Film Career
Hollywood Ventures
In addition to his music career, Willie Nelson has also made a mark in Hollywood. His distinctive personality and on-screen presence have landed him roles in several films and television shows. Notable appearances include roles in "The Electric Horseman" (1979), "Honeysuckle Rose" (1980), and "Barbarosa" (1982). These acting gigs have added a significant amount to Willie Nelson net worth.
Television Appearances
Nelson's char
WRI’s brand new “Food Service Playbook for Promoting Sustainable Food Choices” gives food service operators the very latest strategies for creating dining environments that empower consumers to choose sustainable, plant-rich dishes. This research builds off our first guide for food service, now with industry experience and insights from nearly 350 academic trials.
"Understanding the Carbon Cycle: Processes, Human Impacts, and Strategies for...MMariSelvam4
The carbon cycle is a critical component of Earth's environmental system, governing the movement and transformation of carbon through various reservoirs, including the atmosphere, oceans, soil, and living organisms. This complex cycle involves several key processes such as photosynthesis, respiration, decomposition, and carbon sequestration, each contributing to the regulation of carbon levels on the planet.
Human activities, particularly fossil fuel combustion and deforestation, have significantly altered the natural carbon cycle, leading to increased atmospheric carbon dioxide concentrations and driving climate change. Understanding the intricacies of the carbon cycle is essential for assessing the impacts of these changes and developing effective mitigation strategies.
By studying the carbon cycle, scientists can identify carbon sources and sinks, measure carbon fluxes, and predict future trends. This knowledge is crucial for crafting policies aimed at reducing carbon emissions, enhancing carbon storage, and promoting sustainable practices. The carbon cycle's interplay with climate systems, ecosystems, and human activities underscores its importance in maintaining a stable and healthy planet.
In-depth exploration of the carbon cycle reveals the delicate balance required to sustain life and the urgent need to address anthropogenic influences. Through research, education, and policy, we can work towards restoring equilibrium in the carbon cycle and ensuring a sustainable future for generations to come.
Characterization and the Kinetics of drying at the drying oven and with micro...Open Access Research Paper
The objective of this work is to contribute to valorization de Nephelium lappaceum by the characterization of kinetics of drying of seeds of Nephelium lappaceum. The seeds were dehydrated until a constant mass respectively in a drying oven and a microwawe oven. The temperatures and the powers of drying are respectively: 50, 60 and 70°C and 140, 280 and 420 W. The results show that the curves of drying of seeds of Nephelium lappaceum do not present a phase of constant kinetics. The coefficients of diffusion vary between 2.09.10-8 to 2.98. 10-8m-2/s in the interval of 50°C at 70°C and between 4.83×10-07 at 9.04×10-07 m-8/s for the powers going of 140 W with 420 W the relation between Arrhenius and a value of energy of activation of 16.49 kJ. mol-1 expressed the effect of the temperature on effective diffusivity.
Artificial Reefs by Kuddle Life Foundation - May 2024punit537210
Situated in Pondicherry, India, Kuddle Life Foundation is a charitable, non-profit and non-governmental organization (NGO) dedicated to improving the living standards of coastal communities and simultaneously placing a strong emphasis on the protection of marine ecosystems.
One of the key areas we work in is Artificial Reefs. This presentation captures our journey so far and our learnings. We hope you get as excited about marine conservation and artificial reefs as we are.
Please visit our website: https://kuddlelife.org
Our Instagram channel:
@kuddlelifefoundation
Our Linkedin Page:
https://www.linkedin.com/company/kuddlelifefoundation/
and write to us if you have any questions:
info@kuddlelife.org
UNDERSTANDING WHAT GREEN WASHING IS!.pdfJulietMogola
Many companies today use green washing to lure the public into thinking they are conserving the environment but in real sense they are doing more harm. There have been such several cases from very big companies here in Kenya and also globally. This ranges from various sectors from manufacturing and goes to consumer products. Educating people on greenwashing will enable people to make better choices based on their analysis and not on what they see on marketing sites.
2. What is Particulate Matter?
Particulate matter (PM)
describes a wide variety of
airborne material. PM pollution
consists of materials (including
dust, smoke, and soot), that are
directly emitted into the air or
result from the transformation of
gaseous pollutants. Particles
come from natural sources (e.g.,
volcanic eruptions) and human
activities such as burning fossil
fuels, incinerating wastes, and
smelting metals.
Image from http://www.epa.gov/eogapti1/
module3/distribu/distribu.htm
3. How is PM Regulated?
PM is one of the six EPA “criteria pollutants” that have been
determined to be harmful to public health and the environment.
(The other five are ozone, sulfur dioxide, nitrogen dioxide,
carbon monoxide, and lead.)
EPA is required under the Clean Air Act to set national ambient
air quality standards (NAAQS) to protect public health from
exposure to these pollutants. Areas that exceed the NAAQS are
designated as nonattainment, and must institute air pollution
control programs to reduce air pollution to levels that meet the
NAAQS.
4. PM
Where Does PM Originate?
VOCs
NO2
SO2
Sources may emit PM directly into the environment or emit precursors
such as sulfur dioxide (SO2), nitrogen dioxide (NO2), and volatile
organic compounds (VOCs), which are transformed through
atmospheric chemistry to form PM.
Ammonia (NH3)
Ammonia (NH3)
5. Sources of PM and PM Precursors
Mobile Sources
(vehicles)
VOCs, NO2, PM
Stationary Sources
(power plants, factories)
NO2, SO2, PM
Area Sources
(drycleaners, gas stations)
VOCs
Natural Sources
(forest fires, volcanoes)
PM
6. Determinants of PM Concentration
• Weather patterns
• Wind
• Stability (vertical movement of air)
• Turbulence
• Precipitation
• Topography
• Smokestack height and temperature of gases
Nearby natural and built structures may lead to downward moving
currents causing aerodynamic or building downwash of
smokestack emissions.
7. The Role of Inversions
An inversion is an extremely
stable layer of the atmosphere
that forms over areas.
Temperature inversions trap
pollutants close to the ground.
These inversions involve layers
of hot air sitting above cooler air
near ground level. When
particles accumulate in the air
layer, they are unable to rise
into the atmosphere where
winds will disperse them.
Source: http://www.epa.gov/apti/ course422/
ce1.html
8. 1930: Meuse River Valley, Belgium
• An inversion led to a high concentration of
pollutants during a period of cold, damp
weather
• Main sources: zinc smelter, sulfuric acid
factory, glass manufacturers
• 60 deaths recorded
1948: Donora, Pennsylvania
• Similar inversion to Meuse River Valley
• Main sources: iron and steel factories, zinc
smelting, and an acid plant
• 20 deaths observed
1952: London
• Killer fog (right)
• Primary source: domestic coal burning
• 4,500 excess deaths recorded during week-
long period in December
The Great London Smog
(1952)
Major Episodes of Severe Air Pollution
due to Inversions
9. Establishing a particle size
definition for irregularly shaped
particles necessitates the use of a
standardized measure referred to
as the aerodynamic diameter,
measured in microns or
micrometers (μm), a unit equal to
one millionth of a meter. The graph
at the right shows the distribution of
the 4 main particle size categories,
with the categories historically and
currently regulated by EPA
indicated below. By comparison, a
human hair is approximately 70
microns in diameter.
Top: Modified from Online Reference Module by JR
Richards et al. http://registrar.ies. ncsu.edu/ol_2000.
Bottom: U.S. EPA. Office of Research and Development.
Particulate Matter:
Aerodynamic Diameter
10. Size is important to the behavior
of PM in the atmosphere and
human body and determines the
entry and absorption potential
for particles in the lungs.
Particles larger than 10 mm are
trapped in the nose and throat
and never reach the lungs.
Therefore, particles 10 mm in
diameter or less are of most
concern for their effects on
human health. Particles between
5 and 10 mm are removed by
physical processes in the throat.
Particles smaller than 5 mm
reach the bronchial tubes, while
particles 2.5 mm in diameter or
smaller are breathed into the
deepest portions of the lungs.
Image: PM2.5. By D. Hershey. From New York
State Department of Environmental Conservation.
http://www.dec.state.ny.us/website/dar/baqs/micro
/two.html
Particulate Matter:
Size Matters
11. • Premature death
• Lung cancer
• Exacerbation of COPD
• Development of chronic lung disease
• Heart attacks
• Hospital admissions and ER visits for heart and lung disease
• Respiratory symptoms and medication use in people with
chronic lung disease and asthma
• Decreased lung function
• Pre-term birth
• Low birth weight
What Adverse Health Effects
Have Been Linked to PM?
12. Increasing Evidence of
Cardiovascular Effects
Until the mid 1990s, most
research focused on the
association of PM exposure with
respiratory disease. Since then,
there has been growing evidence
of cardiovascular health effects
from PM.
Source: Pope and Dockery, JAWMA, 2006
13. Toxicological, clinical and
epidemiological studies have
increased understanding of the
mechanism of action by which
PM leads to mortality and lung and
heart disease.
For example, at right are stained
photomicrographs of abdominal
arteries from mice exposed to
filtered air and air polluted with fine
particulate matter, with the
increased arterial blockage in the
PM-exposed mice providing
scientific support for the link
between PM and atherosclerosis
found in a study of human subjects
(Kunzli et al., 2005). Sun et al. JAMA, 2005
Integrating Toxicology, Epidemiology
and Clinical Studies
14. Several theories have been advanced as to the mechanism of
action. It is likely that more than one mechanism is involved in
causing PM-related health effects. Theories include the following:
4. PM causes inflammation
of lung tissue, resulting in
the release of chemicals
that impact heart function;
5. PM causes changes in
blood chemistry that
results in clots that can
cause heart attacks.
1. PM leads to lung irritation
which leads to increase
permeability in lung tissue;
2. PM increases susceptibility to
viral and bacterial pathogens
leading to pneumonia in
vulnerable persons who are
unable to clear these infections;
3. PM aggravates the severity
of chronic lung diseases
causing rapid loss of airway
function;
How Does PM Cause Health Effects?
15. Types of Air Pollution and Health
Studies
• Ecologic study – Examines the association between exposure rates
and disease rates in a group over time. In ecologic studies, the
exposure and disease status of individuals in the group are unknown.
Therefore, one limitation of this study design is that those exposed and
those with the disease may not be the same individuals.
• Time-series study – Analyzes a series of data points that results from
repeated measurements over time. Adjustments are made for cyclical
or seasonal trends such as daily peaks in PM levels or annual influenza
trends in order to identify larger trends that demonstrate the association
between exposure and disease.
• Cohort study – The health status of individuals in a cohort (i.e., group
of study participants) whose exposure status is known at the start of the
study is monitored over time to see if there is an association between
their exposure and particular health outcomes.
16. Donora, PA at noon on Oct. 29, 1948. Photo source:
Pittsburgh Post-Gazette
The Evolution of Air Pollution
Research Methods - Early Studies
Early studies of air pollution
concentrated on the severe
episodes described earlier.
These episodes demonstrated a
clear link between increased
levels of ambient pollution and
adverse health outcomes.
Methods used to describe these
events included population
surveys, ecological studies,
and, later, time-series analyses.
17. The London Fog event of
1952 provides a clear
example of an early time-
series analysis. The figure
to the right shows the
estimates of weekly
mortality and average sulfur
dioxide concentrations for
London during the winter of
1952-53. Deaths in
December increased
approximately 2.5 times
over comparable periods in
1947 to 1951, and remained
elevated through February
1953. Source: http://www.portfolio.mvm.ed.ac.uk/
studentwebs/session4/27/greatsmog52.htm
The Evolution of Air Pollution
Research Methods - The London Fog
18. The modern era of air pollution
research involved using laboratory
sampling equipment and
epidemiologic methods to
determine personal exposures and
to monitor health effects. These
efforts were used in the Harvard
Six Cities Study, a prospective
study pioneered in 1973, in which
mortality data from a cohort of
adults in six cities with different
levels of air pollution were
analyzed, controlling for behavioral
risk factors such as smoking. This
study led to more complex
techniques for both measuring
exposure and modeling the
exposure-response relationship
between PM and health endpoints.
Source: Dockery D, et al. An Association between
Air Pollution and Mortality in Six U.S. Cities, NEJM
1993; 329 (24):1753-1759.
P=Portage, WI H=Harriman, TN
T=Topeka, KS L=St. Louis, MO
W=Watertown, MA
S=Steubenville, OH
The Evolution of Air Pollution
Research Methods - Modern Studies
19. More recent studies have
introduced sophisticated statistical
approaches to the time-series
relationship. The National
Morbidity, Mortality, and Air
Pollution Study (NMMAPS) has
made substantial contributions
towards understanding the
association of PM with mortality by
applying a consistent approach to
data collected at 90 different sites
across the nation.
The graph at the right shows the
relative rates of mortality per 10 μg
increase in PM10 levels for the 90
individual study sites.
The Evolution of Air Pollution
Research Methods - Multiple Sites
Source: Samet JM, Zeger SL, Dominici FD et al. 2000. The
National Morbidity, Mortality, and Air Pollution Study. Part
II: Morbidity and Mortality from Air Pollution in the United
States. Cambridge, MA: Health Effects Institute.
20. Air Pollution Research:
Setting the Future Agenda
The Committee on Research Priorities for Airborne Particulate
Matter was established by the National Research Council in January
1998 in response to a request from Congress and the EPA. The
Committee produced 4 reports over the period 1998 – 2004.
I. Immediate Priorities
and a Long-Range
Research Portfolio
II. Evaluating Research
Progress and Updating
the Portfolio
III. Early Research
Progress
IV. Continuing Research
Progress
21. Research Priorities
The Committee identified ten research areas of priority in
establishing the relation between PM exposure and public health:
1. Outdoor measures vs. actual
human exposure
2. Exposures of susceptible
subpopulations to toxic PM
components
3. Characterization of emission
sources
4. Air-Quality-Model development
and testing
5. Assessment of hazardous
particulate matter components
6. Dosimetry: Deposition and
fate of particles in the
respiratory tract
7. Combined effects of PM and
gaseous co-pollutants
8. Susceptible subpopulations
9. Mechanisms of injury
10. Analysis and measurement