2. Pollution
The word pollution was derived from the latin word
‘pollutus’ meaning ‘to make unclean ‘.
Pollution is the introduction of contaminants into
the natural environment that cause adverse
change.[1] Pollution can take the form of chemical
substances or energy, such as noise, heat or
light. Pollutants, the components of pollution, can be
either foreign substances/energies or naturally
occurring contaminants. Pollution is often classed
as point source or nonpoint source pollution.
3. Air pollution : What is it ?
Air pollution is the introduction
of chemicals, particulates, biological materials, or
other harmful materials into the Earth's atmosphere,
possibly causing disease, death to humans, damage to
other living organisms such as food crops, or
the natural or built environment.
4. Air pollution : Causes
The conditions of air are made unclean
due to introduction of foreign elements
from :
1. Natural Sources
2. Man made sources
5. Natural Sources
Dust from natural sources, usually large areas of land
with few or no vegetation
Methane, emitted by the digestion of food by animals,
for example cattle
Smoke and carbon monoxide from wildfires
Volcanic activity, which produces sulfur, chlorine, and
ash particulates
6. Man made sources
Mobile Sources include motor vehicles, marine
vessels, and aircraft.
Fumes from paint, hair spray, varnish, aerosol
sprays and other solvents
Waste deposition in landfills, which
generate methane
tationary Sources include smoke stacks of power
plants, etc.
7. Pollutants
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
8. Different types of pollutants
and their sources
Pollutants
Natural Sources
Man made sources
Particulates :
Mist ,smoke ,fumes ,dust.
Disintegration of rocks
and soil.
Insecticides, oil and
tobacco smoke, chemical
processes etc.
Oxides of sulphur :
SO2 , SO3
Decay of plants and
animals
Volcanic eruptions
Burning of fossil fuels,
sulphuric acid plants ,
smelting plants etc.
Oxides of nitrgen :
NO , NO2 , N20
Lightening discharge
Microbes
Automobile exhausts
,fertilizer industry etc.
Oxides of carbon :
CO , CO2
Volcanic eruptions
Respiration
Incomplete combustion
of petrol ,fossil fuel
combustion.
Hydrogen sulphide :
H2S
Volcanic eruptions
By product in industrial
processes
9. Effects of air pollution
Air pollution is a significant risk factor for multiple health
conditions including respiratory infections, heart
disease, and lung cancer, according to the WHO. The
health effects caused by air pollution may include difficulty
in breathing, wheezing, coughing, asthma and aggravation
of existing respiratory and cardiac conditions. These effects
can result in increased medication use, increased doctor or
emergency room visits, more hospital admissions and
premature death. The human health effects of poor air
quality are far reaching, but principally affect the body's
respiratory system and the cardiovascular system.
10. Effects : Part 2
Air pollution also leads to :
Acid Rain :Acid rain is a rain or any other form
of precipitation that is unusually acidic, meaning
that it possesses elevated levels of hydrogen ions
(low pH).
II. Global warming :Global warming refers to an
unequivocal and continuing rise in the average
temperature of Earth's climate system.
III. Ozone depletion :Ozone depletion is depletion of
the amount of ozone in the atmosphere.
I.
11. How do we Prevent it ?
There are various air pollution control technologies
and land use planning strategies available to reduce air
pollution.[53][54] At its most basic level land use planning is
likely to involve zoning and transport infrastructure
planning. In most developed countries, land use planning
is an important part of social policy, ensuring that land is
used efficiently for the benefit of the wider economy and
population as well as to protect the environment.
Like :Control devices
Reduction of emissions and the environmental impact
assessment.