The document discusses environmental pollution and the components of the environment. It focuses on the ozone layer, how CFCs and other gases cause its depletion, and the effects of this depletion. Specifically, it explains that CFCs released into the atmosphere rise up and break down in the stratosphere, releasing chlorine atoms that destroy ozone molecules. This causes the ozone layer to thin out, leading to increased UV radiation reaching the Earth's surface and negative impacts on human health, ecosystems, climate change and more.

1. BY KANGKAN LIGIRA
E N V I R O N M E T A L E N G I N E E R
ENVIRONMENTAL
POLLUTION

2. What is environment ?
 Environment is the sum total of chemical ,
physical , biological , social or environmental
factor which constitutes the surrounding of
living beings.

3. Types of Environment
Natural Man-Made
Air
Water
Soil
Forest
House
Agriculture
Transportation
etc

4. COMPONENTS OF ENVIRONMENT
 Biotic Components – Flora And Fauna
 Abiotic Components – Lithosphere , Hydrosphere ,
Atmosphere
 Energy Components – Solar Energy , Hydro Energy ,
Geo-chemical Energy , Nuclear Energy etc.

5. Biotic Components
It comprises the living part of the environment,
which includes the association of a number of
interrelated populations belonging to different
species in a common environment.

6. Abiotic Components
It comprises the non-living part of the environment.

7. Atmosphere –
 Layer of air that surrounds the earth.
Its is thick near the ground and gets thinner as we
go up.
Components –
 Troposphere
 Stratosphere
 Mesosphere
 Thermosphere

8.  Troposphere
Lowermost layer of the atmosphere where life exists and
weather changes occur like cloud formation , rainfall , snowfall etc.
 Stratosphere
• Layer above troposphere.
• Extends upto 35 kms from troposphere.
• Aeroplanes fly in this region.
 Mesosphere
• Layer above stratosphere.
• Here temperature is very cold.
 Thermosphere
 Here lightening and thunderstrom occurs.

10. Ozone
• Gas with 3 – Atoms of O2 (Oxygen).
• Protects from U-V rays of the Sun.
• Acts as an protective Umbrella .
 Formation of Ozone Layer :-
Begins with photo-dissociation of Oxygen molecules by solar
radiation at wavelength less than 240 nm.
UV < 240 nm
O2 ------------------ O + O (Oxygen Atoms)
O + O2 + M ------------------ O3 + M
M= Some inert substance
This process is known as Chapman Cycle.

11. Physical Properties of Ozone –
• Blue gas with irritating / unpleasant smell.
• Causes irritation to eyes , skin cancer , coughing and chest
troubles.
• More soluble than oxygen in water.
• Boils at 161 k and solidifies to violet – black crystals , which
melts at 81 k.

12. Ozone Layer Depletion –
• Gases like CFC , HCFC , Halons and Halogens.
• Released to Atmosphere (Stratosphere).
• U-V Radiation between 1760 and 22000 A present in
stratosphere decomposes them.
• The Cholorine , Flourine or Bromine molecules of CFC’s and
Halons are converted into their reactive free radical form by
photochemical reaction.

13. Ozone Layer Depletion –
Sunlight
CFCL3 ------------------ CFCL2 + CL
Sunlight
CFCL2 ------------------ CFCL + CL
Sunlight
CF2CL2 ------------------ CF2CL + CL
Sunlight
CCLF2 ------------------ CCLF + F

14. Ozone Layer Depletion –
• For this reason Ozone layer is becoming thinner. This is
called Ozone layer depletion
• Concentration of Ozone in the stratosphere is about 10 ppm
compared to 0.05 ppm in the troposhere.
• Rise of Concentration of Ozone in troposhere cause injuries
to human and vegetation. But stratospheric Ozone layer is
essential for life to sustain on the earth.
• This layer absorbs the U-V radiation from the sun and
convert it into heat and chemical energy.

15. Ozone Layer Depletion Effects–
 Ozone hole Formation :-
• Ozone hole formation over Antartica. This Ozone hole leads
to melting of ice of Antartica , increase sea level and other
harmful effects on it’s environment.
 Effect on Aquatic System:-
• Affects phytoplanktons , fish , larval crabs. Decrease in
phytoplankton increase the CO2 in the atmosphere which
contribute the GLOBAL WARMING.

16. Ozone Layer Depletion Effects–
 Effect on Materials:-
• Degradation of paints and plastics.
 Effect on Climate :-
• GLOBAL WARMING – increasing the average
temperature of the earth’s surface.
 Effect on Human Health :-
• Damage genetic materials in the cells which leads to more
people suffering from Cataract, Causes Skin cancer , allergies
and some other infectious diseases.
• 10% depletion in Ozone layer results in 30% increase in skin
cancer infection.

17. Ozone Layer Depletion Effects–
 Effect on Vegetation:-
• Crop fields especially tea , cabbage and soya-bean will be
reduced.
• Reduction in leaf size , poor seed quality , increase
susceptibility to weeds and diseases.
• Plant proteins are excellent absorbers of U-V rays and hence
susceptible to injury.