Sources of Air Pollution

1. Sources of Air Pollution
Lecture II
28-01-2021
Dr. Misbah Sultan

2. Air pollution,
“presence of substances in the atmosphere that are harmful to the health of
humans and other living beings, or cause damage to the climate or to
materials”
“release of various gases, finely divided solids, or finely dispersed
liquid aerosols into the atmosphere at rates that exceed the natural
capacity of the environment to dissipate and dilute or absorb them. These
substances may reach concentrations in the air that cause undesirable health,
economic, or aesthetic effects”
Air pollution is not same anywhere

3. There are complex links between air pollutant emissions and air quality.
These include
 emission heights,
 chemical transformations,
 reactions to sunlight,
 additional natural and hemispheric contributions and
 the impact of weather and topography.
Significant cuts in emissions are essential for improving air quality.

4. Pollution On The Move
 Air Pollution is often created in one
place and transported.
 Sometimes chemical reactions in the
atmosphere change pollutants before
they are deposited.
 e.g. POPs in Antarctica

5. Types of Pollutants
 Primary Pollutants
- passed from the source
directly into the environment
- categorized into
aerosols, reduced, and
oxidized
- less toxic
- do not show synergism
 Secondary Pollutants
- made from reactions
between primary pollutants
and environmental
constituents
- usually oxidizing
- more toxic
- show synergism

6. Types of Sources
There are four main types of air pollution sources:
 mobile sources – such as cars, buses, planes, trucks, and trains
 stationary sources – such as power plants, oil refineries, industrial
facilities, and factories
 area sources – such as agricultural areas, cities, and wood burning
fireplaces
 natural sources – such as wind-blown dust, wildfires, and volcanoes

7. Criteria pollutants
 Clean, dry air consists primarily of nitrogen and oxygen—78 percent and
21 percent respectively, by volume. The remaining 1 percent is a mixture of
other gases, mostly argon (0.9 percent), along with trace (very small)
amounts of carbon dioxide, methane, hydrogen, helium, and more. Water
vapor is also a normal, though quite variable, component of the
atmosphere, normally ranging from 0.01 to 4 percent by volume.
 There are six major air pollutants that have been designated by the
U.S. Environmental Protection Agency (EPA) as
“criteria” pollutants—criteria meaning that the concentrations of these
pollutants in the atmosphere are useful as indicators of overall air

8. pollutant common sources
maximum
acceptable
concentration in
the atmosphere
environmental
risks
human health
risks
Source: U.S. Environmental Protection Agency
carbon monoxide
(CO)
automobile
emissions, fires,
industrial
processes
35 ppm (1-hour
period); 9 ppm
(8-hour period)
contributes to
smog formation
exacerbates
symptoms of
heart disease,
such as chest
pain; may cause
vision problems
and reduce
physical and
mental
capabilities in
healthy people
Criteria pollutants

9. pollutant common sources
maximum
acceptable
concentration in
the atmosphere
environmental
risks
human health
risks
Source: U.S. Environmental Protection Agency
nitrogen oxides
(NOx)
automobile
emissions,
electricity
generation,
industrial
processes
0.053 ppm (1-
year period)
damage to
foliage;
contributes to
smog formation
inflammation and
irritation of
breathing
passages
Criteria pollutants

10. Criteria pollutants
pollutant common sources
maximum
acceptable
concentration in
the atmosphere
environmental
risks
human health
risks
Source: U.S. Environmental Protection Agency
sulfur dioxide
electricity
generation, fossil-
fuel combustion,
industrial
automobile
emissions
0.03 ppm (1-year
period); 0.14 ppm
(24-hour period)
major cause of
haze; contributes
acid rain
which
damages foliage,
buildings, and
monuments; reacts
to form particulate
matter
breathing
difficulties,
particularly for
people with
and heart disease

11. Criteria pollutants
pollutant common sources
maximum
acceptable
concentration in
the atmosphere
environmental
risks
human health
risks
Source: U.S. Environmental Protection Agency
ozone (O3)
nitrogen oxides
(NOx) and volatile
organic
(VOCs) from
industrial and
automobile
emissions, gasoline
vapours, chemical
solvents, and
electrical utilities
0.075 ppm (8-hour
period)
interferes with the
ability of certain
plants to respire,
leading to
increased
susceptibility to
other
environmental
stressors (e.g.,
disease, harsh
weather)
reduced lung
function; irritation
and inflammation
of breathing
passages

12. Criteria pollutants
pollutant common sources
maximum
acceptable
concentration in
the atmosphere
environmental
risks
human health
risks
Source: U.S. Environmental Protection Agency
particulate matter
sources of primary
particles include
fires, smokestacks,
construction sites,
and unpaved
sources of
secondary particles
include reactions
between gaseous
chemicals emitted
by power plants
and automobiles
150 μg/m3
(24-
period for particles
<10 μm); 35
μg/m3
(24-hour
period for particles
<2.5 μm)
contributes to
formation of haze
as well as acid rain,
which changes the
pH balance of
waterways and
damages foliage,
buildings, and
monuments
irritation of
breathing
aggravation of
asthma, irregular
heartbeat

13. Criteria pollutants
pollutant common sources
maximum
acceptable
concentration in
the atmosphere
environmental
risks
human health
risks
Source: U.S. Environmental Protection Agency
lead (Pb)
metal processing,
waste incineration,
fossil-fuel
combustion
0.15 μg/m3
(rolling
three-month
average); 1.5
μg/m3
(quarterly
average)
loss of
decreased
reproduction,
neurological
problems in
vertebrates
adverse effects
upon multiple
bodily systems;
contribute to
learning
when young
children are
exposed;
cardiovascular
effects in adults

14.  Hundreds of specific substances are considered hazardous when present in
trace amounts in the air. These pollutants are called air toxics.
 Many of them cause genetic mutations or cancer;
 some cause other types of health problems, such as adverse effects on
brain tissue or fetal development.
 Although the total emissions and the number of sources of air toxics are
small compared with those for criteria pollutants, these pollutants can
pose an immediate health risk to exposed individuals and can cause other
environmental problems.
 Examples: heavy metals like Ni, Hg, Cd, As, radionuclides, organic
compound like benzene etc.
Air Toxics

15. Pollutant Sources
arsenic
volcanoes, weathering of rocks and minerals containing arsenic,
industrial processes such as metal smelting, burning wood that has
been treated with arsenic compounds
asbestos natural deposits, building materials
benzene
burning coal and oil, vehicle exhaust, industrial solvents, tobacco
smoke
beryllium compounds burning coal and oil, tobacco smoke, natural occurrence in soil
cadmium compounds
burning fossil fuels, incineration of waste, smelting of zinc, lead, and
copper
chlorine papermaking, drinking water, swimming pools
coke oven emissions coke ovens
Air Toxics

16. Pollutant Sources
cyanide compounds automobile exhaust, chemical processing, waste incineration
formaldehyde
building materials and home furnishings, power plants, incineration of
waste, automobile exhaust, tobacco smoke
lead compounds battery manufacturing, paints and ceramic glazes, metal products
mercury compounds
paint manufactured prior to 1990–91, batteries, industrial processes,
dental amalgam fillings, fish products
nickel compounds nickel processing, fossil-fuel burning, sewage sludge incineration
radionucleides (radon,
radium, uranium)
ambient air (radon, uranium), drinking water (uranium), uranium mines
and processing facilities, phosphate fertilizers
selenium compounds
drinking water and ambient air, some plastics and paints,
pharmaceutical production
vinyl chloride
manufacture of polyvinyl chloride (PVC), which is used in pipes,
furniture, and automobiles
Air Toxics

17. Air Toxics……………. Effects on health
 headache,
 nausea,
 eye and skin irritation
 and death
 CNS disorders
 thyroid disorders
 respiratory tract issues
 inflammation of mouth,
esophagus, and stomach if
ingested
 lung and nasopharyngeal
cancer
 gastrointestinal disorders
 reduced fertility
 fetal effects including low birth
weight and mental
impairment
 blindness, and deafness
 kidney damage
 dermatitis and asthma
 bone cancer
 loss of consciousness,
 inhibition of blood clotting;
 liver cancer
 anemia

18. AQI (Air Quality Index)
AQI Color Levels of Concern Values of Index Description of Air Quality
Green Good 0 to 50 Air quality is satisfactory, and air pollution poses little or
no risk.
Yellow Moderate 51 to 100 Air quality is acceptable. However, there may be a risk for
some people, particularly those who are unusually
sensitive to air pollution.
Orange Unhealthy for Sensitive
Groups
101 to 150 Members of sensitive groups may experience health
effects. The general public is less likely to be affected.
Red Unhealthy 151 to 200 Some members of the general public may experience
health effects; members of sensitive groups may
experience more serious health effects.
Purple Very Unhealthy 201 to 300 Health alert: The risk of health effects is increased for
everyone.
Maroon Hazardous 301 and higher Health warning of emergency conditions
everyone is more likely to be affected.
ground-level ozone;
particle pollution (also known as particulate matter, including
PM2.5 and PM10)
carbon monoxide;
sulfur dioxide;
nitrogen dioxide