AIR POLLUTION
WHAT IS AIR POLLUTION?
Air pollution is the contamination
of air due to the presence of substances in the atmosphere
that are harmful to the health of humans and other living
beings, or cause damage to the climate or to materials. There
are many different types of air pollutants, such as gases,
particulates, and
biological molecules.
DO YOU KNOW?
Air pollution is the greatest
environmental threat to public health globally and
accounts for an estimated 7 million premature deaths
every year. Air pollution and climate change are closely
linked as all major pollutants have an impact on the
climate and most share common sources with greenhouse
gases. Improving our air quality will bring health,
development, and environmental benefits.
TYPES OF AIR POLLTION?
There are two basic types of pollutants in the air. They are known as primary
pollutants and secondary pollutants.
Primary pollutants enter the air directly. Some are released by natural processes, like ash from
volcanoes . Most are released by human activities.
Carbon oxides are released when fossil fuels burn.
Nitrogen oxides form when nitrogen and oxygen combine at high temperatures. This occurs in hot
exhausts from vehicles, factories, and power plants.
Sulfur oxides are produced when sulfur and oxygen combine. This happens when coal that contains
sulfur burns.
Particulates are solid particles. These particles may be ash, dust, or even animal wastes. Many are
released when fossil fuels burn.
as a brown haze in the air. Photochemical smog forms when certain pollutants have a chemical
reaction in the presence of sunlight. Photochemical smog consists mainly of ozone (O3). Ozone
near the ground is a pollutant. This ozone is harmful to humans and other living things.
However, ozone in the stratosphere protects Earth from the Sun's harmful ultraviolet radiation.
OUTDOOR AIR
POLLUTION
Outdoor air pollution is a
complex mixture of pollutants originating from natural and
anthropogenic sources, including transportation, power generation,
industrial activity, biomass burning, and domestic heating and
cooking. The mix of pollutants in outdoor air varies widely in space
and time, reflecting the diversity of sources and the influence of
atmospheric processes. Commonly measured air pollutants include
particulate matter (PM2.5, PM10), nitrogen dioxide, and sulfur
dioxide; the concentration of particulate matter is often used as an
indicator of pollution levels. Millions of people worldwide are
exposed to outdoor air pollution at levels that substantially exceed
existing health-based guidelines.
INDOOR AIR POLLUTION
Household air pollution is generated by the use of inefficient and polluting
fuels and technologies in and around the home that contains a range of
health-damaging pollutants, including small particles that penetrate deep
into the lungs and enter the bloodstream.
ACID RAIN
When acid rain and dry acidic particles fall to earth, the nitric and sulfuric acid
that make the particles acidic can land on statues, buildings, and other
manmade structures, and damage their surfaces. The acidic particles corrode
metal and cause paint and stone to deteriorate more quickly.
