SMK Bukit Jambul
Science Form 1
Class : 1 Dinamik
Teacher’s name :PuanSitiIndriati
1 . What is air pollution?
2. Examples of air pollution?
3. Sources of air pollution
4. The effects of air pollution to
human and environment
5. The steps needed to prevent
and control air pollution
6. Ways to keep the air clean
7. Practising habitats that keeps
the air clean
What is air pollution?
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.
There are several main types of pollution and well-known
effects of pollution which are commonly discussed. These
include smog, acid rain, the greenhouse effect, and
"holes" in the ozone layer. Each of these problems has
serious implications for our health and well-being as well
as for the whole environment.
One type of air 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. Some
authorities believe that even the burning of wood and charcoal in fireplaces
and barbeques can release significant quanitites of soot into the air.
Another type of 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 acid rain.
Pollution also needs to be considered inside our homes, offices, and
schools. Some of these pollutants can be created by indoor activities such
as smoking and cooking. 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. It is therefore important to consider both indoor and
Examples of air pollution
Noise pollution or unwanted sounds that are carried by the air, have
an irritating and detrimental effect on humans and other animals.
Careful planning of streets and biuldings in towns and better control
over noisy vechiles may add to the control of noise pollution.
Tobacco smoke is one of the major forms of pollution in buildings. It is
not only the smoker who is infected, but everyone who inhales the
polluted air. There is a very strong connection between smoking and
lung cancer. Bronchitis is common among smokers and unborn
babies of mothers who smoke also suffer from the harmful effects of
Exhaust Gases of Vehicles
Pollution from exhaust gases of vehicles is reponsible for 60% of all
air pollution and in cities up to 80%. There is a large variety of
harmful chemicals present in these gases, with lead being one of the
Combustion of Coal
The combustion of caol without special precautions can have serious
consequences. If winds do not blow away the poisonous gases, they
can have fatal effects and may lead to death.
Acid rain is the term for pollution caused when sulfur and nitrogen
dioxides combine with atmospheric moisture to produce highly acidic
rain, snow, hail, or fog. The acid eats into the stone, brick and metal
articles and pollutes water sources. Coal in South Africa is rich in
sulphur and the power stations in the Mpumalanga Province could be
reponsible for acid rain over other areas of our country.
Sources of air pollution
The combustion of gasoline and other hydrocarbon fuels in
automobiles, trucks, and jet airplanes produces several primary pollutants:
nitrogen oxides, gaseous hydrocarbons, and carbon monoxide, as well as
large quantities of particulates, chiefly lead. In the presence of sunlight,
nitrogen oxides combine with hydrocarbons to form a secondary class of
pollutants, the photochemical oxidants, among them ozone and the eyestinging peroxyacetylnitrate (PAN).
Nitrogen oxides also react with oxygen in the air to form nitrogen
dioxide, a foul-smelling brown gas. In urban areas like Los Angeles where
transportation is the main cause of air pollution, nitrogen dioxide tints the
air, blending with other contaminants and the atmospheric water vapor to
produce brown smog.
Although the use of catalytic converters has reduced smog-producing
compounds in motor vehicle exhaust emissions, recent studies have
shown that in so doing the converters produce nitrous oxide, which
contributes substantially to global warming.
In cities, air may be severely polluted not only by transportation but
also by the burning of fossil fuels (oil and coal) in generating stations,
factories, office buildings, and homes and by the incineration of garbage.
The massive combustion produces tons of ash, soot, and other
particulates responsible for the gray smog of cities like New York and
Chicago, along with enormous quantities of sulfur oxides (which also may
be result from burning coal and oil).
These oxides rust iron, damage building stone, decompose nylon,
tarnish silver, and kill plants. Air pollution from cities also affects rural
areas for many miles downwind.
Every industrial process exhibits its own pattern of air pollution.
Petroleum refineries are responsible for extensive hydrocarbon and
particulate pollution. Iron and steel mills, metal smelters, pulp and paper
mills, chemical plants, cement and asphalt plants—all discharge vast
amounts of various particulates. Uninsulated high-voltage power lines
ionize the adjacent air, forming ozone and other hazardous pollutants.
Airborne pollutants from other sources include insecticides,
herbicides, radioactive fallout, and dust from fertilizers, mining operations,
and livestock feedlots.
The effects of air
pollution to human and
Effects on human
Air pollution can affect our health in many ways with both short-term and
long-term effects. Different groups of individuals are affected by air
pollution in different ways. Some individuals are much more sensitive to
pollutants than are others. Young children and elderly people often suffer
more from the effects of air pollution. People with health problems such as
asthma, heart and lung disease may also suffer more when the air is
polluted. The extent to which an individual is harmed by air pollution usually
depends on the total exposure to the damaging chemicals, i.e., the
duration of exposure and the concentration of the chemicals must be taken
Examples of 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 allergic reactions.
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 pollution.
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 elderly.
It is estimated that half a million people die prematurely every year in the
United States as a result of smoking cigarettes.
Research into the health effects of air pollution is ongoing. Medical
conditions arising from air pollution can be very expensive. Healthcare
costs, lost productivity in the workplace, and human welfare impacts cost
billions of dollars each year.
Acid rain is precipitation containing harmful amounts of nitric and
sulfuric acids. These acids are formed primarily by nitrogen oxides and
sulfur oxides released into the atmosphere when fossil fuels are burned.
These acids fall to the Earth either as wet precipitation (rain, snow, or fog)
or dry precipitation (gas and particulates). Some are carried by the wind,
sometimes hundreds of miles. In the environment, acid rain damages trees
and causes soils and water bodies to acidify, making the water unsuitable
for some fish and other wildlife. It also speeds the decay of buildings,
statues, and sculptures that are part of our national heritage. Acid rain has
damaged Massachusetts lakes, ponds, rivers, and soils, leading to
damaged wildlife and forests.
Eutrophication is a condition in a water body where high
concentrations of nutrients (such as nitrogen) stimulate blooms of algae,
which in turn can cause fish kills and loss of plant and animal diversity.
Although eutrophication is a natural process in the aging of lakes and some
estuaries, human activities can greatly accelerate eutrophication by
increasing the rate at which nutrients enter aquatic ecosystems. Air
emissions of nitrogen oxides from power plants, cars, trucks, and other
sources contribute to the amount of nitrogen entering aquatic ecosystems.
Haze is caused when sunlight encounters tiny pollution particles in
the air. Haze obscures the clarity, color, texture, and form of what we see.
Some haze-causing pollutants (mostly fine particles) are directly emitted to
the atmosphere by sources such as power plants, industrial facilities, trucks
and automobiles, and construction activities. Others are formed when
gases emitted to the air (such as sulfur dioxide and nitrogen oxides) form
particles as they are carried downwind.
Effects on wildlife. Toxic pollutants in the air, or deposited on soils
or surface waters, can impact wildlife in a number of ways. Like humans,
animals can experience health problems if they are exposed to sufficient
concentrations of air toxics over time. Studies show that air toxics are
contributing to birth defects, reproductive failure, and disease in animals.
Persistent toxic air pollutants (those that break down slowly in the
environment) are of particular concern in aquatic ecosystems. These
pollutants accumulate in sediments and may biomagnify in tissues of
animals at the top of the food chain to concentrations many times higher
than in the water or air.
Ozone depletion. Ozone is a gas that occurs both at ground-level
and in the Earth's upper atmosphere, known as the stratosphere. At ground
level, ozone is a pollutant that can harm human health. In the stratosphere,
however, ozone forms a layer that protects life on earth from the sun's
harmful ultraviolet (UV) rays. But this "good" ozone is gradually being
destroyed by man-made chemicals referred to as ozone-depleting
substances, including chlorofluorocarbons, hydrochlorofluorocarbons, and
These substances were formerly used and sometimes still are used
in coolants, foaming agents, fire extinguishers, solvents, pesticides, and
aerosol propellants. Thinning of the protective ozone layer can cause
increased amounts of UV radiation to reach the Earth, which can lead to
more cases of skin cancer, cataracts, and impaired immune systems. UV
can also damage sensitive crops, such as soybeans, and reduce crop
Crop and forest damage.Air pollution can damage crops and trees
in a variety of ways.Ground-level ozone can lead to reductions in
agricultural crop and commercial forest yields, reduced growth and
survivability of tree seedlings, and increased plant susceptibility to disease,
pests and other environmental stresses (such as harsh weather). As
described above, crop and forest damage can also result from acid rain
and from increased UV radiation caused by ozone depletion.
Global climate change.The Earth's atmosphere contains a delicate
balance of naturally occurring gases that trap some of the sun's heat near
the Earth's surface. This "greenhouse effect" keeps the Earth's temperature
stable. Unfortunately, evidence is mounting that humans have disturbed
this natural balance by producing large amounts of some of these
greenhouse gases, including carbon dioxide and methane. As a result, the
Earth's atmosphere appears to be trapping more of the sun's heat, causing
the Earth's average temperature to rise - a phenomenon known as global
warming. Many scientists believe that global warming could have significant
impacts on human health, agriculture, water resources, forests, wildlife, and
Steps needed to
prevent and control air
Save energy around the house. According to the U.S. Environmental
Protection Agency, saving energy can reduce carbon emissions. Because
most energy sources require burning fossil fuels, the less energy you use,
the greener you are. Set your appliances and lights on a timer to turn off
after a certain period of inactivity. Use compact fluorescent bulbs instead of
standard lightbulbs, and use your microwave instead of the oven to heat
small items. (See References 3)
Manage your heating and cooling. Turn your thermostat down in the winter
and up in the summer whenever you are at work, sleeping or on vacation.
You can also turn your water heater down to 120 degrees to save power.
Make sure your insulation is up to the recommended level for your area,
and insulate pipes that pass through unheated spaces. Check to see that
your windows and doors are not leaking warm or cool air. To make sure
your furnace and air conditioners are running efficiently, perform regular
maintenance. (See References 3)
Cut back on the amount of packaging you purchase and the amount of
household waste you produce. The process of manufacturing packaging
releases harmful emissions into the atmosphere, so patronize brands that
use as little packaging as possible. Recycle everything you can: aluminum,
paper, glass, plastic and cardboard are usually easy to recycle. When you
are disposing of chemical-based substances like paint, batteries, pesticides
or solvents, check with your local waste management office for a safe, ecofriendly method. (See References 3)
Reduce the amount of time you spend in the car. Carpool or use public
transportation whenever you can. For shorter distances, walk or ride your
bike to do errands. According to the U.S. Department of Transportation,
changing to carpooling can save a person over $1,000 per year. If you
avoid driving alone only one day every week for a year, you can save
hundreds of dollars in expenses, not to mention the wear and tear on your
car. When you must drive, refill your gas tank during colder times of the day
and avoid spilling gas to prevent evaporation into the atmosphere.
Improve your fuel economy. According to the EPA, a 1 percent increase in
fuel economy equals a 1 percent decrease in carbon dioxide emissions
(see References 1). Avoid accelerating quickly, braking hard and driving at
high speeds, particularly when in heavy traffic. Remove excess weight from
your car and remove unused roof racks or bike carriers, which cause drag.
Ways to keep the air
Walk or Bike
Instead of automatically grabbing your car keys for every errand, walk or
ride your bike whenever you can. Increase your opportunities to get there
under your own steam by switching to neighborhood shops, restaurants
and service providers. Leaving your car at home the equivalent of just one
day each week reduces your yearly greenhouse gas emissions up by to
800 pounds, according to the Environmental Protection Agency. You'll keep
the air cleaner, save money and get fit.
The term "eCycling" means recycling used electronics, by refurbishing
them for new users or reusing their metal, glass and plastic. Recycling
electronics reduces the need for mining and processing new materials. It
also keeps hazardous parts made of chromium and lead from polluting the
air, reports the Environmental Protection Agency.
Take your old computers, televisions, cell phones and other gadgetry to an
electronics recycling center instead of putting them in the trash. Many
retailers and manufacturers offer electronic recycling options, as do some
Refuel Without Vapors
Avoid letting vapors escape when you put gas in your car. Gasoline vapors
contribute to ozone problems, and they're toxic if you breathe them. Don't
top off your tank after the pumps clicks. Continuing to pump causes vapors
to escape from the pump nozzle and increases your chances of a spill.
Overfilling can also damage your car's vapor collection system, since gas
expands in your tank.
Take extra care refueling during hot weather, when vapor production
increases, suggests the Environmental Protection Agency. Fill the tank
early in the morning or at night, especially on ozone action days, and make
sure you tighten your gas cap afterward.
Protect and Plant Trees
Encourage community preservation and planting, and plant trees around
your own home. Trees remove carbon dioxide from the air, up to 25 pounds
per tree each year, according to Power Scorecard. They also produce
clean, new oxygen and help cool the air.