Air
pollution is the introduction of particulates,
biological
molecules, or other harmful materials into Earth's atmosphere, causing diseases, death to
humans, damage to other living organisms such as animals and food crops, or the
natural or built
environment. Air pollution may come from natural sources. The atmosphere is a complex natural gaseous system that is
essential to support life on planet Earth. Stratospheric
ozone
depletion due to air pollution has been recognized as a threat to
human health as well as to the Earth's ecosystems.
Indoor air pollution and urban air quality are listed as two of the world's
worst toxic pollution problems in the 2008 Blacksmith Institute World's Worst
Polluted Places report. According to the 2014 WHO report, air pollution
in 2012 caused the deaths of around 7 million people worldwide. To learn about
air quality click here… http://www.airnow.gov/
An air pollutant is a substance in the air that can
have adverse effects on humans and the ecosystem. The substance can be solid
particles, liquid droplets, or gases. A pollutant can be of natural origin or
man-made. Pollutants are classified as primary or secondary. Primary pollutants
are usually produced from a process, such as ash from a volcanic eruption.
Other examples include carbon monoxide gas from motor vehicle exhaust,
or the sulfur dioxide released from factories.
Secondary pollutants are not emitted directly. Rather, they form in the air
when primary pollutants react or interact. Ground level ozone is a prominent example of a
secondary pollutant. Some pollutants may be both primary and secondary: they
are both emitted directly and formed from other primary pollutants.
A lack of
ventilation indoors concentrates air pollution where people often spend the
majority of their time. Radon (Rn) gas, a carcinogen,
is exuded from the Earth in certain locations and trapped inside houses.
Building materials including carpeting and plywood emit formaldehyde
(H2CO) gas. Paint and solvents give off volatile organic compounds (VOCs) as they
dry. Lead
paint can degenerate into dust and be inhaled. Intentional air pollution is introduced
with the use of air fresheners, incense,
and other scented items. Controlled wood fires in stoves and fireplaces
can add significant amounts of smoke particulates into the air, inside and out.
Indoor pollution fatalities may be caused by using pesticides
and other chemical sprays indoors without proper ventilation. To learn more
about indoor air quality click here…http://www.epa.gov/indoor-air-quality-iaq
