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Air becomes polluted with the release of harmful gases
and particles.
Air Pollution
Air pollution refers to the discharge of harmful gases
and dust into the atmosphere. When these harmful substances enter
the air around us, they may cause irreversible damage to humans and
to our environment.
Some of the main air
pollutants are:
- Sulphur
dioxide (SO2)
- Carbon
monoxide (CO)
- Ozone
(O3)
- Nitrogen
dioxide (NO2)
So,
what about those gases?
- SULPHUR DIOXIDE
- Responsible
for acid rain.
CARBON MONOXIDE
- Enters the
blood stream and reduces the delivery of oxygen to the body's
organs and tissues.
Elevated levels of CO may result in impairment of visual
perception, work capacity, manual dexterity, learning ability and
performance of complex tasks.
OZONE
- Damage to
lung tissues and reduces lung functioning.
Reduces agricultural crop yield; causes foliar damage in many crops
and trees.
NITROGEN DIOXIDE
- Contributes
to acid rain.
Irritates lungs and lowers resistance to respiratory infections
e.g. influenza
Scientists also have found
that some of these air pollutants are responsible for the following
phenomena:
What causes air pollution?
Air pollution can be
caused by two main components, natural and human
factors.
Natural factors such as
volcano eruptions and natural forest fires often cause tons of ash
and tiny air pollutants to be released to our earth's
atmosphere.
Did You Know?
According to the World's Health Organization, each year about tens
of thousands of people die in the world's major cities due to the
breathing in of poor quality air. As many as one billion people
around the world are regularly exposed to pollution levels up to
100 times more than WHO guidelines. |
However, the human factors
are much more devastating.
- IN INDUSTRIES
- The most
serious cause of air pollution is heavy industrial activity.
Many heavy
industries produce a large amount of air pollutants. This often causes air
pollution.
IN POWER PLANTS
- When fossil
fuels such as coal and oil are burnt to produce electricity, large
quantities of sulphur dioxide and nitrogen dioxide ( gases that are
responsible for acid rain) are released into the air. These
substances are damaging to the environment and all
things.
IN VEHICLES
- Vehicles
use either diesel or petrol to generate power and, as a result,
produce fumes that contain lead and carbon monoxide which pollute
the environment and harm living things.
IN DEVELOPING COUNTRIES
- In these
countries, the burning of wood and animal waste for cooking and
heating also adds pollutants into the air.
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