• Air is the ocean we breathe.
• Air supplies us with oxygen which is
essential for our bodies to live. Air is
99.9% nitrogen, oxygen, water vapor
and inert gases.
• Human activities can release
substances into the air, some of which
can cause problems for humans,
plants, and animals.
Atmosphere structure and
A. What is the atmosphere?
1. Outermost layer of the Earth
2.Comprised of gas, turbulently flowing,
held in by gravity
3.Formed by out gassing of the Earth’s
interior, since modified by many
Earth system processes
4. Compared to the lithosphere and
hydrosphere, the atmosphere is more
rapidly changing and dynamic
5. Basic atmospheric variables
a. Solar energy – sunshine is the major energy
source for atmospheric and Earth surface
b. Humidity and precipitation (moisture)
c. Winds – governed by atmospheric pressure
Types of Pollution
• acid rain
• the greenhouse effect
• "holes" in the ozone layer
• Each of these problems has serious
implications for our health and well-
being as well as for the whole
Effects of Pollution
• Pollutants which have an immediate
effect are primary air pollutants
• Those that become a problem when
converted to other forms are
secondary air pollutants.
• Primary pollutants include carbon
monoxide, radioactive wastes and
highly toxic compounds such as
xylenes, cyantes, and atmospheric
• Secondary pollutants include low level
ozone which is produced by sunlight
reacting with the exhaust from
• Some pollutants are natural components
of the atmosphere and become pollutants
when they reach critical levels that
affect life. These natural pollutants
include such things as volcanic eruptions,
violent storms, forest fires, wind erosion,
natural gases from the decay of dead
organisms, and pollen and spores.
Threats to humans
• The Environmental Protection
Agency (EPA) has identified six
primary pollutants that present a
threat to human health: carbon
monoxide, low level ozone, lead,
the sulfur oxides, the nitrogen
oxides, and particulate matter.
• Carbon Monoxide: A colorless, odorless,
poisonous gas, produced by incomplete
burning of carbon-based fuels including
gasoline, oil and wood as well as
combustion of many natural and synthetic
products such as cigarettes.
• When carbon monoxide gets into the
body, it combines with chemicals in the
blood and prevents the blood from
transporting oxygen to the cells of the
Low Level Ozone
• Low Level Ozone: A variation of oxygen
which contains three atoms of oxygen
instead of two.
• Ozone occurs in nature; it is the cause of
the sharp smell you notice near a lightning
• Ozone is found in large concentrations in
the stratosphere where it protects the
earth from ultraviolet radiation.
• Ground level ozone is the main component
of smog, and is a product of reactions
during combustion of coal, gasoline and
other fuels, and also chemicals found in
products including solvents, paints and
• In humans, it can cause lung tissue damage,
and create high incidences of asthma and
• Plants exposed to high ozone
concentrations lose their chlorophyll and
their food manufacturing abilities.
• Lead: There has been a dramatic
decrease of lead in human blood
levels since the element has been
removed from gasoline and paints.
Sources for lead in our
environment, are large furnaces,
incinerators, and battery plants.
• Lead in the atmosphere can deposit
into lakes and streams where it may
be ingested by fish and eventually by
• The physical effects of lead poisoning
are mental impairment, central
nervous system damage and high
• Sulfur Dioxide: A gas produced by burning
coal, most notably in power plants, as well
as some industrial processes such as paper
production and the smelting of metals.
• Sulfur dioxide plays an important role in
the production of acid rain. Sulfur dioxide
can cause nose and throat irritation and
lung problems such as bronchitis.
• Nitrogen Oxide: Nitrogen Oxides
(NOx) are produced from burning
fuels including gasoline and coal.
• The major sources of NOx are power
plants and transportation--vehicles
that burn gasoline and diesel.
• Nitrogen Oxides react with organic
compounds to form smog, and are also
major components of acid rain.
• Particulate Matter: Particulate
Matter (PM) includes dust, soot and
other tiny bits of solid materials
that are released into and move
around in the air.
• U.S. health standards for air quality
are based on the concentration of
particles small enough to be inhaled
deep into the lungs.
• These are particles with a diameter
of less than 10 microns. Particulates
are produced by many sources,
including burning of diesel fuels,
incineration of garbage, mixing and
application of fertilizers and
pesticides, road construction and
industrial processes such as
steelmaking, mining operations or
• Particulate pollution can cause eye,
nose and throat irritation and other
• Fine-particulate air pollution
(particles with a diameter of 2.5
microns or less) tend to deposit in
the alveoli of the lungs where they
remain for a long time.
• Fine-particle pollution typically
contains soot, acid condensates, and
sulfate and nitrate particles. This
type of pollution is thought to pose
greater health risks not only because
the particles can be breathed more
deeply into the lungs, but also
because they are more likely to be
more toxic than larger particles.
• One type of particulate pollution is the
release of particles into the air from
burning fuel for energy. Diesel smoke
is a good example of this particulate
matter . The particles are very small
pieces of matter measuring about 2.5
microns or about .0001 inches.
• This type of pollution is sometimes
referred to as "black carbon" pollution.
• The exhaust from burning fuels in
automobiles, homes, and industries is a
major source of pollution in the air.
• Another type of particulate pollution
is the release of noxious gases, such
as sulfur dioxide, carbon monoxide,
nitrogen oxides, and chemical vapors.
These can take part in further
chemical reactions once they are in
the atmosphere, forming smog and
• Smog is a type of large-scale outdoor
• It is caused by chemical reactions
between pollutants derived from
different sources, primarily automobile
exhaust and industrial emissions.
• Cities are often centers of these types
of activities, and many suffer from the
effects of smog, especially during the
warm months of the year.
• The exact causes of pollution may be
different. Depending on the
geographical location, temperature,
wind and weather factors, pollution is
dispersed differently. However,
sometimes this does not happen and
the pollution can build up to
• A temperature inversion occurs when
air close to the earth is cooler than
the air above it. Under these
conditions the pollution cannot rise
and be dispersed.
• Cities surrounded by mountains also
experience trapping of pollution.
• Inversion can happen in any season.
Winter inversions are likely to cause
particulate and or inversions are more
likely to create smog.
• Another consequence of outdoor air
pollution is acid rain. When a
pollutant, such as sulfuric acid
combines with droplets of water in
the air, the water (or snow) can
become acidified . The effects of acid
rain on the environment can be very
Acid Rain damage
• Acid rain damages plants by
destroying their leaves
• it poisons the soil
• it changes the chemistry of lakes
• Damage due to acid rain kills
trees and harms animals, fish,
and other wildlife.
The Greenhouse effect
• The Greenhouse Effect, also
referred to as global warming, is
generally believed to come from
the build up of carbon dioxide gas
in the atmosphere.
• Carbon dioxide is produced when
fuels are burned.
• Plants convert carbon dioxide back to
oxygen, but the release of carbon
dioxide from human activities is
higher than the world's plants can
• The situation is made worse since
many of the earth's forests are being
removed, and plant life is being
damaged by acid rain.
• Thus, the amount of carbon dioxide in
the air is continuing to increase. This
buildup acts like a blanket and traps
heat close to the surface of our
• Changes of even a few degrees will
affect us all through changes in the
climate and even the possibility that
the polar ice caps may melt.
• Chemicals released by our activities
affect the stratosphere , one of the
atmospheric layers surrounding earth.
The ozone layer in the stratosphere
protects the earth from harmful
ultraviolet radiation from the sun.
• Release of chlorofluorocarbons
(CFC's) from aerosol cans, cooling
systems and refrigerator equipment
removes some of the ozone, causing
"holes"; to open up in this layer and
allowing the radiation to reach the
• Ultraviolet radiation is known to
cause skin cancer and has damaging
effects on plants and wildlife.
Indoor Air pollution
• Pollution also needs to be considered
inside our homes, offices, and
• In the United States, we spend about
80-90% of our time inside buildings,
and so our exposure to harmful indoor
pollutants can be serious.
Sources of indoor pollution
• There are many sources of indoor air
pollution. Tobacco smoke, cooking and
heating appliances, and vapors from
building materials, paints, furniture,
etc. cause pollution inside buildings.
• Radon is a natural radioactive gas
released from the earth, and it can
be found concentrated in basements
in some parts of the United States.
• Pollution exposure at home and work
is often greater than outdoors.
• The California Air Resources Board
estimates that indoor air pollutant
levels are 25-62% greater than
outside levels and can pose serious
• Radon-222 is a radioactive gas released during
the natural decay of thorium and uranium, which
are common, naturally occurring elements found
in varying amounts in rock and soil. Odorless,
invisible, and without taste, radon cannot be
detected with the human senses.
• Radon-222 decays into radioactive elements, two
of which -- polonium-218 and polonium-214 -- emit
alpha particles, which are highly effective in
damaging lung tissues. These alpha-emitting radon
decay products have been implicated in a causal
relationship with lung cancer in humans.
Characteristics and Sources
• Outdoors, where it is diluted radon poses
significantly less risk than indoors.
• In the indoor air environment, the
magnitude of radon concentration indoors
depends primarily on a building's
construction and the amount of radon in
the underlying soil.
• The soil composition under and around a
house affects radon levels and the ease
with which radon migrates toward a
• Normal pressure differences between the
house and the soil can create a slight
vacuum in the home that can draw radon
gas from the soil into the building.
• Radon gas can enter a home from the soil
through cracks in concrete floors and
walls, floor drains, sump pumps,
construction joints, and tiny cracks or
pores in hollow-block walls.
• Radon levels are generally highest in
basements and ground floor rooms that
are in contact with the soil.
• Factors such as the design, construction,
and ventilation of the home affect the
pathways and sources that can draw
• Another source of radon indoors may be
air released by well water during
showering and other household activities.
• Molds produce tiny spores to reproduce.
Mold spores waft through the indoor and
outdoor air continually.
• When mold spores land on a damp spot
indoors, they may begin growing and
digesting whatever they are growing on in
order to survive.
• There are molds that can grow on wood,
paper, carpet, and foods.
• The key to mold control is moisture
control. It is important to dry water
damaged areas and items within 24-48
hours to prevent mold growth.
• Clean up the mold and get rid of the
excess water or moisture. Fix leaky
plumbing or other sources of water.
Wash mold off hard surfaces with
detergent and water, and dry
completely. Absorbent materials (such
as ceiling tiles & carpet) that become
moldy may have to be replaced.
• Although noise is a significant environmental
problem, it is often difficult to quantify associated
costs. An OECD report on the social costs of land
transport identified four categories of impact from
• productivity losses due to poor concentration,
communication difficulties or fatigue due to
• health care costs to rectify loss of sleep, hearing
problems or stress
• lowered property values
• loss of psychological well-being.
Healthaffect our health in
• Air pollution can
many ways with both short-term and
• Different groups of individuals are
affected by air pollution in different
• Some individuals are much more
sensitive to pollutants than are others.
Young children and elderly people often
suffer more from the effects of air
• People with health problems such as
asthma, heart and lung disease may
also suffer more when the air is
• The extent to which an individual is
harmed by air pollution usually
depends on the total exposure to the
• Short-term effects include
irritation to the eyes, nose and
throat, and upper respiratory
infections such as bronchitis and
pneumonia. Other symptoms can
include headaches, nausea, and
• Short-term air pollution can
aggravate the medical conditions of
individuals with asthma and
emphysema. In the great "Smog
Disaster" in London in 1952, four
thousand people died in a few days
due to the high concentrations of
• Long-term health effects can include
chronic respiratory disease, lung
cancer, heart disease, and even
damage to the brain, nerves, liver, or
kidneys. Continual exposure to air
pollution affects the lungs of growing
children and may aggravate or
complicate medical conditions in the