“Any undesirable change in the physical, chemical and
biological characteristics of the environment (air, water, soil)
which can cause harmful effects on various life forms or
1. Air Pollution
2. Water Pollution
3. Noise Pollution
4. Soil Pollution
5. Marine Pollution
6. Thermal Pollution
7. Nuclear Pollution
Types of Pollution
Air pollution may be described as “the imbalance
in quality of air so as to cause adverse effects on
the living organisms existing on earth”.
Air pollution is generally disequilibrium condition of
air caused due to the introduction of foreign
elements from natural & man made sources to the
air so that it becomes injurious to biological
Air pollutants may occur in gaseous or particular form and
may be organic or inorganic in nature.
PRIMARY POLLUTANTS: These are emitted directly from the
point source Eg:-CO,NOX, SOx, Radioactive substances,
SECONDARY POLLUTANTS: These are formed by
interaction of primary pollutants with other primary pollutants
Eg:-O3, Peroxyacetyl nitrate (PAN), Photochemical smog
• Some primary air pollutants may react with one
another or with other chemicals in the air to form
secondary air pollutants.
Composition of unpolluted air
• Carbon dioxide
• Nitrous oxide
• Organic vapors
PARTS PER MILLION(VOL)
Major air pollutants are
• Carbon monoxide
• Carbon dioxide
• Nitrogen oxide
• Suspended particulate matter
Causes of Air Pollution
1. NATURAL SOURCES of air pollution are volcanic
eruptions, forest fires, sea and salt sprays etc
2. MAN MADE sources include thermal power plants,
industrial units, vehicular emissions, fossil fuel burning,
Agricultural activities etc
3. Automobile engines, incomplete combustion of fuels in
4. Lead particles from automobile exhaust, soot, fly ash from
power station from asbestos, fluorides, aluminium metallic
dusts, etc., and other natural sources. 12
Sources of air pollution
Domestic burning of fuel
Burning of fossil fuels
Waste treatment plants
• Forest fires
• Sulphur springs
• Spray from the oceans
• Natural geysers
• Deflation of sands and dust
• Natural organic & inorganic
• Marsh gases
• Extra terrestrial bodies
• Cosmic dust
• Pollen grains of flowers
• Soil debris
• Fungal spores
• Photochemical reactions
Indoor Air Pollution
•The most important indoor air pollutant is Radon gas.
•This is emitted from building materials like bricks, concrete,
tiles etc which are derived from soil containing radium.
•During cooking (in rural) coal, kerosene are using.
•The incomplete combustion produces CO and SO2.
•Along with these some other toxic agents are HCHO and BAP
(benzo-(a) pyrene). BAP is also found in Cigar smoke.
EFFECTS OF AIR POLLUTION
ON HUMAN HEALTH
Exposure to air pollutants causes lung cancer, asthma chronic
bronchitis and emphysema.
Particulate matter causes decreasing of visibility and lung diseases.
CO when reacts with blood forms carboxyheamoglobin and causes
suffocation, dizziness, unconsciousness and even death.
Many other pollutants like benzene (from unleaded petrol), HCHO and
particulates like Polychlorinated biphenyls (PCBs), toxic metals and
dioxins (from burning of polythene) can cause mutations, reproductive
The hazardous materials like Asbestos, Beryllium, Mercury, Arsenic and
radioactive substances cause cancer, lung diseases, kidney, liver,
spleen, brain problems.
• Burning sensation in
eyes & nose
• Throat irritation
• Severe asthma
• Hay fever
• Loss of coordination
• Decrease in lung
• Digestive problems
EFFECTS ON PLANTS
• Effects on plants:
Damage to leaf structure causes
• Necrosis (dead area of leaf),
• Chlorosis (loss of chlorophyll causing yellowing of leaf),
• Epinasty (downward curling of leaf) and
• Abscission (dropping of leaves).
6/29/2022 Source: Confidential 22
•Effect on aquatic life: Air pollutants mixing up with rain can cause high acidity
in fresh water lakes leads to death of fishes and other aquatic life forms.
•Effect on Materials: Corrosion of metallic surfaces, disfigurement of statues
made up of marble and limestone. SO2 causes damage to book bindings, paper,
leather, fabric and paint. O3 can cause cracking of rubber, nylon, damage to the
tyres and fading of cotton and rayon fibres
• Reduction of pollutant discharge at the source by the application of control
• Reduction at the source through raw material changes, operational changes
or modifications, or replacement of process equipment and controlling
devices like cyclones, bag house filters, Wet scrubbers and electrostatic
• Dilution of the source discharge by the use of tall stacks
• Dispersion of source locations through allocation of land usage i.e., proper
planning and zoning of industrial areas
• The hazardous chemicals should be converted into less-harmful substances.
• Instead of using low grade and conventional fuels, environment-friendly fuels
such as GOBAR GAS, LPG,and natural gas should be generated and used.
• The vehicular pollution can be controlled by using good-quality fuel, by
keeping engine fully effective and minimizing the use of motored vechicles.
Stricter fuel standards should be set.
• For effective control of air pollution, raising of green belts must be promoted.
Around 1 a.m. on Monday, the 3rd of December, 1984, in a densely populated region in the
city of Bhopal, Central India, a poisonous vapor burst from the tall stacks of the Union
Carbide pesticide plant.
This vapor was a highly toxic cloud of methyl isocyanine.
Of the 800,000 people living in Bhopal at the time, 2,000 died immediately, and as many as
300,000 were injured.
In addition, about 7,000 animals were injured, of which about one thousand were killed. A
series of studies made five years later showed that many of the survivors were still
suffering from one or several of the following ailments: partial or complete blindness,
gastrointestinal disorders, impaired immune systems, post traumatic stress disorders,
and menstrual problems in women.
A rise in spontaneous abortions, stillbirths, and offspring with genetic defects was also
noted.” (The Bhopal Disaster) This incident we now refer to as the Bhopal Gas Tragedy,
which has also been called “Hiroshima of the Chemical Industry” one of the worst
commercial industrial disasters in history.(Cohen)
BHOPAL GAS TRAGEDY
CAUSES OF NOISE POLLUTION
1.The main sources of noise are various modes of transportation,
industrial operation, construction activities
2.Rocket engine, jet palne take off, thunder cap etc are some
sources of sound
3.Electronic devices such as radio, television,etc., also produce
considerable amount of noise leading to noise pollution inside
4.Bursting of crackers and playing loud music during social
gathering and festivals lead to lot of noise pollution and cause
great discomfort to old and sick people around the area.
5.Exessive use of domestic appliances, such as mixers, washing
EFFECTS OF NOISE POLLUTION
• 1.Interferes with mans communication: in a noisy area communication is
• 2.HEARING DAMAGE: noise can cause temporary or permanent hearing
• 3. Physiological disorders like anxiety, insomnia, high blood pressure,
fatigue etc., occur as a consequence of over exposure to noise.
• 4. Exessive noise leads to poor concentration and reduces the ability to
• 5.Regular exposure to loud noise may cause speech and reading disabilities
in young children.
• 6.Many animals become dull and inactive and their health deteriorates due
to continued exposure to high intensity noise.
1. Reduction in sources of noise
2. Noise making sound machines should be kept in containers
with sound absorbing media
3. Proper oiling will reduce the sound from the machinery
4.Public awareness regarding different modes of noise pollution
should be generated in people.
5.More and more trees should be planted since trees act as sound
absorbers and hence contribute to minimizing noise pollution.
6.Aircraft noise may be reduced by designing engines that makes
7.Industrial noise may be reduced by redesigning the machine
8.Playing music above certain permissible level during marriages
and other social and religious functions should be prohibited,etc.,
CONTROL MEASURES FOR NOISE POLLUTION
Water pollution can be defined as
alteration in physical and chemical,
biological characteristics of water making
it unsuitable for designated use in natural
Causes of water pollution
1. Major point sources of water pollution are industries, power
plants, underground coal mines, offshare oil wells etc..
2. Septic tanks, industries, deep well, injection, mining etc.. are
mainly responsible for underground water pollution
3. Sewage, industrial wastes, synthetic detergents, agro chemical
oil, waste heat are major source of natural pollution
4. Disposal of dead bodies and immersion of idles of gods and
goddesses degrade the quality of water.
5. Modern agriculture practices require the use of large amounts
of fertilizers, pesticides and other soil additives. These slowly
move to water bodies through irrigation rainfall etc and cause
EFFECTS OF WATER POLLUTION
• 1. TOXIC COMPOUNDS: pollutants such as heavy metals, pesticides,
cyanides and many other organic and inorganic compounds are harmful to
aquatic organisms. Toxic substances tend to accumulate in the organism’s
body this process is called “bioaccumulation”.
• 2. PATHOGENS: water born diseases like cholera, dysentery, typhoid,
• 3. EUTROPHICATION: The presence of excess amounts of nitrates and
phosphates in water increases the growth of certain plants on the surface of
water body. This phenomena is called “eutrophication”. This reduces the
oxygen supply to aquatic plants and other living organisms.
chamber Settling tank Aeration tankSettling tank
To river, lak
Sludge drying bed
Disposed of in landfill or
ocean or applied to cropland,
pasture, or rangeland
Odors may cause illness or indicate
presence of harmful gases
Particles of dried sludge carry
viruses and harmful bacteria that
can be inhaled, infect cuts or enter
Children may walk or
play in fertilized fields.
Cows may die after grazing
on sludge-treated fields.
Harmful chemicals and
pathogens may pollute
nearby streams, lakes,
ponds, and wetlands.
Harmful chemicals and
pathogens may leach
into groundwater and
1. Use of nitrogen fixing plants to supplement use of fertilizers
2. Planting trees would reduce pollution by sediments and will
also prevent soil erosion.
3. Non biodegradable waste materials such as plastics should
not be dumped into water bodies.
4. Industrial wastes and affluent should be treated in order to
reduce their toxicity.
5. Human activities such as bathing and washing in rivers,
ponds and lakes, washing animals, throwing half burnt dead
bodies and idols made of plaster of paris must be completely
6. Rural people should be aware of the effects caused due to
CONTROL MEASURES FOR WATER POLLUTION
Soil pollution can be defined as
alteration in physical and chemical,
biological characteristics of soil making
it unsuitable for designated use in
Causes of soil pollution
1.Thermal power plants generate a large quantity of fly ash, huge
quantities of these wastes are dumped on the soils and pollute the
2.Agrochemicals released with the wastes of pesticide and
fertilizers factories or during agricultural practices also reach the
soil and pollute it
3.Soil also receive excreta from animals and humans. the sewage
sludge contains many pathogenic organisms, bacteria causes
4. Mining leads to change in structure and composition of soil and
hence causes soil pollution.
5. Construction of dams, houses, factories etc leaves the land in
the adjacent areas unfit for agriculture hence contribute into water
EFFECTS OF SOIL POLLUTION
• 1. Sewage and industrial effluents which pollute the soil ultimately effect human
• 2. Some of the persistent toxic chemicals inhibit the non-target organisms, flora and
fauna and reduce soil productivity
• 3. Nitrogen and phosphorous from the fertilizers in soil reach hear by water bodies
with agricultural run-off and cause eutrophication.
• 4. The disposal of industrial wastes on fertile lands degrade the quality of soil and
renders the land unfit for use in the long-run.
• 5. Radio-active elements that are present in the pollutant soil enter the food chain
through plants. They cause a number of adverse health effects such as cancer,
deformities in bones, etc in humans and animals.
1. Solid wastes should be properly collected and disposed off by
2. Effluents should be properly treated before discharging them on
3. The disposal of hazardous radio-active wastes into the soil
should be prohibited as it is almost impossible to completely
cleans the soil of radio-active elements.
4. The use of chemical fertilizers and pesticides should be
minimized as far as possible.
5.Planting of trees must be encouraged. Trees bind the soil and
prevent the loss of fertile top soil during heavy rains and floods
CONTROL MEASURES FOR SOIL POLLUTION
Causes of Thermal pollution
1.Heat producing industries .i.e..thermal power plants, nuclear power plants,
refineries, steel mills, etc are major sources.
2. Power plants utilize only 1/3 of the energy provided by fossil fuel for their
operations. Remaining 2/3 is generally lost in the form of heat to the water
used for cooling .They reach water bodies which causes thermal pollution of
3. Soil erosion and contamination of water also cause retention of heat hence
contributing to thermal pollution.
EFFECTS OF THERMAL POLLUTION
• 1.Toxicity of pesticides ,detergents and chemicals in the effluents increase
with increase in pollution.
• 2.Fish migration is affected due to formation of various thermal zones.
• 3.The increase in water temperature may cause the activities of certain
pathogenic micro-organisms to accelerate.
• 4.The heated industrial effluents may contain toxic pollutants such as
cadmium, copper and arsenic that may make the water unsuitable for any
Water from condencers is stored in ponds where natural evaporation cools the
Here water from condensers is received in spray ponds and water is sprayed
through nozzles where fine droplets are formed and dissipated to atmosphere.
a).Wet cooling towers,dry cooling towers are used.
b).The excess heat energy that is produced in the generation of electricity may
be utilized in another industry where this energy may be required.This process
is called co-generation.
CONTROL MEASURES FOR THERMAL
Causes of Marine pollution
1.Rivers,which bring pollutants from their drainage
2.Catchment area i.e..coastline where human
settlements in the form of hotels, industry, agricultural
3.Oil drilling and shipment.
4.Discarded nuclear sub-marine and military waste also
causes marine pollution.
5.Water that is used as coolant in power plants and
industrial sites is also responsible for marine pollution.
EFFECTS OF MARINE POLLUTION
• 1.Oil in seawater effects sensitive flora and fauna.
• 2.Death occurs due to loss of buoyancy and subsequent drawing of birds.
• 3.Phytoplankton, zooplankton, algal species ,various species of
invertebrates, coal reefs, birds, fish are affected by oil pollution.
• 4.Consumption of marine food obtained from such polluted water cause a
number of fatal diseases such as viral hepatitis, cholera, typhoid and
• 5.Toxicity of the water is increased due to the addition of heavy metals which
adversely effects the marine life.
1.Development activities on coastal areas should be minimized.
2.Oil ballast should not be dumped into sea.
3.Dumping of toxic, hazardous wastes and sewage sludge should be banned.
4.Oil and grease from service stations should be proceed for reuse.
5.Sewage and industrial waste should be treated before releasing into sea
6.Solid wastes such as plastic, glass, metal, papers etc. should be recycled for
different purposes instead of being discarded as wastes.
CONTROL MEASURES FOR MARINE POLLUTION
Causes of Nuclear pollution
Causes of Nuclear pollution
NATURAL SOURCES: Like cosmic rays from outer
space, radioactive radon-222,soil, rocks, air, water and
1.Anthropogenic Sources:- like nuclear power plant,
nuclear accidents, X-rays, test laboratories etc.
EFFECTS OF NUCLEAR POLLUTION
• 1.Genetic damages: This damages is caused by radiations which effects
genes chromosomes and often seen in the off springs and may be
transmitted upto several generations.
• 2.Somatic damage:-Includes burns, miscarriages, eye cataract and cancer
of bone, thyroid, breast cancer etc…
• 3.Radio nuclides enter the water bodies coming in contact with the
contaminated soil or rock.
1. Setting of nuclear power plant should be carefully
done after studying long term and shot term effects
2. Proper disposal of water from laboratory involving the
use of radio isotopes should be done
CONTROL MEASURES FOR NUCLEAR POLLUTION
At a height between 15-60 Kms, there is a layer of
ozone in the upper atmosphere. This layer is very
important for the existence of life on earth.
The depletion of ozone layer is due to the use of
chemicals called aerosol spry pollutants like
fluorocarbons and chlorofluorocarbons.
The aerosols released form jet planes remove the
ozone layer. Freon gas is used in refrigerators and air
conditioners release fluorocarbons-CFCs are mainly
used as refrigerants, solvents, forming agents and as
aerosol propellants for such products as deodorants,
hairspray, and spray paint.
Depletion of Ozone Layer
The Stratospheric Ozone Layer: a
Giant Umbrella for Earth
Ozone in the stratosphere protects the
biosphere of the Earth by absorbing
harmful ultraviolet radiation in the range
of ~200-310 nm.
OZONE Is An oxygen molecule consists of two oxygen
molecules. When an oxygen molecule (O2) is struck by
UV radiation, it splits into two separate oxygen atoms
Free oxygen molecules can then combine with oxygen
molecules to create ozone, or O3.
•Ozone is a triatomic form of oxygen
(O3) found in Earth’s upper and lower
•The ozone layer, situated in the
stratosphere about 15 to 30 km above
the earth's surface.
•Ozone protects living organisms by
absorbing harmful ultraviolet
radiation (UVB) from the sun.
•The ozone layer is being destroyed
by CFCs and other substances.
• Ozone depletion progressing
globally except in the tropical zone.
The ozone layer
Lesson 9: Stratospheric Ozone and the
The Thickness of the Ozone Layer
If you compressed the total
amount of ozone throughout
the height of the atmosphere
to a pressure of 1 atmosphere
and measured its height in
millimeters then …
• 1 mm = 100 Dobson Units
• 3 mm = 300 Dobson Units
• 5 mm = 500 Dobson Units
• Different chemicals are responsible for the destruction of the ozone
• Topping the list :
– chlorofluorocarbons (CFC’s)
– man-made, non-toxic and inert in the troposphere
– In the stratosphere are photolysed, releasing reactive chlorine
atoms that catalytically destroy ozone
The depletion of ozone layer is due to the use of chemicals pollutants
like fluorocarbons and chlorofluorocarbons.
The aerosols released form jet planes remove the ozone layer. Freon
gas is used in refrigerators and air conditioners release fluorocarbons-
CFCs are mainly used as refrigerants, solvents, forming agents and
as aerosol propellants for such products as deodorants, hairspray, and
CFC’s and ozone depletion
• Chlorofluorocarbons are created
and used in refrigerators and air
• These chlorofluorocarbons are not
harmful to humans and have been
a benefit to us.
• Once released into the
are bombarded and destroyed by
• In the process chlorine is released
to destroy the ozone molecules
1.UV radiation breaks off a chlorine atom from a CFC molecule.
2.The chlorine atom attacks an ozone molecule (O3), breaking it apart and
destroying the ozone.
3.The result is an ordinary oxygen molecule (O2) and a chlorine monoxide
4.The chlorine monoxide molecule (ClO) is attacked by a free oxygen atom
releasing the chlorine atom and forming an ordinary oxygen molecule (O2).
5.The chlorine atom is now free to attack and destroy another ozone
molecule (O3). One chlorine atom can repeat this destructive cycle
thousands of times.
Destruction of Ozone:
Impacts of Ozone Depletion
• Skin cancer
• Immune system function
• Increased incidence,
severity and duration of
• Reduced efficacy of
• Pathogen locally up &
• Biodiversity locally up &
• Aquatic organisms
• Decreased biomass
• Polar systems especially
• Limiting the use of CFC’s is difficult
• Ban the production and use of CFC’s
• Use CFC substitutes such as HCFC’s and HFC’s
• Recycling refrigerants
• Alternatives to gas-blown plastics
• Alternative propellants
• Alternatives to methyl bromide, a fungicide
What can we do?
• Make sure that technicians working on your car air conditioner,
home air conditioner, or refrigerator are certified by an EPA
approved program to recover the refrigerant (this is required by
• Have your car and home air conditioner units and refrigerator
checked for leaks. When possible, repair leaky air conditioning
units before refilling them.
• Contact local authorities to properly dispose of refrigeration or
air conditioning equipment.
• Protect yourself against sunburn. Minimize sun exposure during
midday hours (10 am to 4 pm). Wear sunglasses, a hat with a
wide brim, and protective clothing with a tight weave. Use a
broad spectrum sunscreen with a sun protection factor (SPF) of
at least 15 and 30 is better.
An increase in the earth's average atmospheric
temperature that causes corresponding changes in
climate and that may result from the greenhouse
• Global warming is the rise in temperate concerning the earth
resulting in climate change
•Heat being trapped in the earth’s atmosphere
•Lead to changes in rainfall pattern, rise in sea level, range of impact
on wildlife, plants and humans
What causes climate change
or global warming?
Carbon dioxide is released into the
- natural processes
(e.g. breathing, decomposition)
- man-made processes
(e.g. car exhaust,
factories, brush fires)
The carbon dioxide builds up in the
atmosphere and absorbs and re-
radiates heat which increases
surface and atmospheric
The buildup of carbon dioxide has
increased exponentially due to human
Causes of Global Warming
One cause is the release of carbon dioxide from everything such as air
planes, buildings, power plants
Another cause like the Greenhouse effect is water vapor increasing in
the air and deforestation
Atmospheric Pollution is the contamination of the
atmosphere with harmful by product of human activity.
Refrigerators releasing chlorofluorocarbons
Green house effect
• The green house effect is the rise in temperature that the earth
experiences because certain gases in the atmosphere trap energy
from the sun.
•What are the Greenhouse gases? Water vapor, CO2, nitrous oxide
(N2O), and methane (CH4).
•These gases are essential for keeping the earth’s temperature in an
ideal range i.e. not too hot and too cold.
• Due to greenhouse gases, the atmosphere absorbs
more infrared energy than it re-radiates to space,
resulting in a net warming of the Earth-atmosphere
system and of surface temperature
• Without the Greenhouse effect our temperature would
drop and we would freeze
• Extreme Weather
• Increase Evaporation
• Sea Level Rise
• Temperature to Rise
• Economy such as, Agriculture, Insurance, Transportation
• Ecosystems such as, Forests, Mountains, and Ecological
• Health by increasing the risk of spreading disease