Air Pollution

What Is Air Pollution?

Air pollution refers to the release of
pollutants into the air—pollutants
that are detrimental to human health
and the planet as a whole. According
to the World Health Organization
(WHO), each year, indoor and
outdoor air pollution is responsible
for nearly seven million deaths
around the globe. Ninety-nine
percent of human beings currently breathe air that exceeds the
WHO’s guideline limits for pollutants, with those living in low- and
middle-income countries suffering the most. In the United States,
the Clean Air Act, established in 1970, authorizes the U.S.
Environmental Protection Agency (EPA) to safeguard public health by
regulating the emissions of these harmful air pollutants.
Sources of Air Pollution
Pollution enters the
Earth's atmosphere in many
different ways. Most air pollution is
created by people, taking the form
of emissions from factories, cars,
planes, or aerosol cans. Second-
hand cigarette smoke is also considered air pollution. These man-
made sources of pollution are called anthropogenic sources.
Some types of air pollution, such as smoke from wildfires or ash
from volcanoes, occur naturally. These are called natural sources.
Air pollution is most common in large cities where emissions from
many different sources are concentrated. Sometimes, mountains or
tall buildings prevent air pollution from spreading out. This air
pollution often appears as a cloud making the air murky. It is
called smog. The word "smog" comes from combining the words
"smoke" and "fog."
Large cities in poor and developing nations tend to have more air
pollution than cities in developed nations. According to the World
Health Organization (WHO), some of the worlds most polluted cities
are Karachi, Pakistan; New Delhi, India; Beijing, China; Lima, Peru;
and Cairo, Egypt. However, many developed nations also have air
pollution problems. Los Angeles, California, is nicknamed Smog City.
Effects On Humans
People experience a wide range of
health effects from being exposed to
air pollution. Effects can be broken
down into short-term effects and long-
term effects.
Short-term effects, which are temporary, include illnesses such as
pneumonia or bronchitis. They also include discomfort such as
irritation to the nose, throat, eyes, or skin. Air pollution can also
cause headaches, dizziness, and nausea. Bad smells made by
factories, garbage, or sewer systems are considered air pollution,
too. These odors are less serious but still unpleasant.
Long-term effects of air pollution can last for years or for an entire
lifetime. They can even lead to a person's death. Long-term health
effects from air pollution include heart disease, lung cancer, and
respiratory diseases such as emphysema. Air pollution can also cause
long-term damage to people's nerves, brain, kidneys, liver, and other
organs. Some scientists suspect air pollutants cause birth defects.
Nearly 2.5 million people die worldwide each year from the effects
of outdoor or indoor air pollution.
People react differently to different types of air pollution. Young
children and older adults, whose immune systems tend to be
weaker, are often more sensitive to pollution. Conditions such as
asthma, heart disease, and lung disease can be made worse by
exposure to air pollution. The length of exposure and amount and
type of pollutants are also factors.
Effects On The Environment
Like people, animals, and plants, entire ecosystems can suffer effects
from air pollution. Haze, like smog, is
a visible type of air
pollution that obscures shapes and
colors. Hazy air pollution can even
muffle sounds.
Air pollution particles eventually fall
back to Earth. Air pollution can
directly contaminate the surface of bodies of water and soil. This can
kill crops or reduce their yield. Sulfur dioxide and nitrogen
oxide particles in the air, can create acid rain when they mix with
water and oxygen in the atmosphere. These air pollutants come
mostly from coal-fired power plants and motor vehicles. When acid
rain falls to Earth, it damages plants by changing soil
composition; degrades water quality in rivers, lakes and streams;
damages crops; and can cause buildings and monuments to decay.
Like humans, animals can suffer health effects from exposure to air
pollution.
Regulation
In addition to the international Kyoto Protocol, most developed
nations have adopted laws to regulate emissions and reduce air
pollution. In the United States, debate is under way about a system
called cap and trade to
limit emissions. This system would
cap, or place a limit, on the amount of
pollution a company is allowed.
Companies that exceeded their cap
would have to pay. Companies that
polluted less than their cap could
trade or sell their remaining pollution
allowance to other companies. In 2006
the World Health Organization issued
new Air Quality Guidelines. The WHOs
guidelines are tougher than most
individual countries existing guidelines.
The WHO guidelines aim to reduce air
pollution-related deaths by 15 percent
a year.
Reduction of air pollution
Anybody can take steps to reduce air
pollution. Millions of people every day make simple changes in their
lives to do this. Taking public transportation instead of driving a car,
or riding a bike instead of traveling in carbon dioxide-
emitting vehicles are a couple of ways to reduce air pollution.
Avoiding aerosol cans, recycling yard trimmings instead of burning
them, and not smoking cigarettes are others.