This document discusses various types of pollution including air, water, soil, noise, and radioactive pollution. It provides details on the classification and sources of different pollutants. The key points are:
1. Air pollution is defined as contamination of the air environment that can harm humans, plants and the environment. Major sources include vehicles, industry, and fires.
2. Primary air pollutants directly emitted include particulate matter, sulfur and nitrogen oxides, carbon monoxide, and volatile organic compounds. Secondary pollutants form from chemical reactions between primary pollutants.
3. Sulfur dioxide mainly comes from burning fossil fuels and causes respiratory issues. Carbon monoxide is odorless and produced by incomplete
2. MODULE I
INTRODUCTION: Classification of Pollution and
Pollutants,
AIR POLLUTION: Primary and Secondary Pollutants,
air pollutants-sulphur dioxide- nitrogen dioxide, carbon
monoxide, Impact of air pollutants on human, vegetation
and environment, Ambient Air Quality Standards
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3. WHAT IS POLLUTION ???
• Effect of undesirable changes in our surrounding that
have harmful effects on plants, animals and human
beings
• Pollution is thus direct or indirect change in any
component of the biosphere
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5. 1. AIR POLLUTION:
• contamination of the indoor or outdoor environment by any
chemical, physical or biological agent that modifies the natural
characteristics of the atmosphere.
• Sources of Air Pollution:
Household combustion devices.
Motor vehicles.
Industrial facilities.
Forest fires
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6. 2.WATER POLLUTION
• contamination of water bodies (e.g. lakes, rivers, oceans,
aquifers and groundwater).
• Water pollution occurs when pollutants are discharged directly
or indirectly into water bodies without adequate treatment to
remove harmful compounds.
• It affects plants and organisms living in these bodies of water.
• In almost all cases the effect is damaging not only to
individual species and populations, but also to the natural
biological communities.
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7. Sources of Water Pollution
Plastics
Pesticides
Heavy metals
Sewage
Radioactive waste
Thermal effluents
Detergents
Food processing waste (fats and grease)
Insecticides and herbicides.
Petroleum hydrocarbons, (gasoline, diesel fuel, jet
fuels, and fuel oil).
Lubricants (motor oil).
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8. 3. SOIL POLLUTION
• caused by the presence of human-made chemicals or other
alteration in the natural soil environment.
• It is typically caused by
Industrial activity.
Agricultural chemicals.
Improper disposal of waste.
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9. 4. NOISE POLLUTION
• Noise means disgust or discomfort hearing from environment.
• Noise pollution is displeasing or excessive noise that may
disrupt the activity or balance of human or animal life.
• Sources of Noise Pollution:
Machines.
Transportation systems.
Motor vehicles.
Aircrafts.
Trains.
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10. 5. RADIOACTIVE POLLUTION
• It occurs when radioactive metals disintegrate releasing
dangerous beta rays which can cause cancer and other
mutative diseases.
• This type of pollution can occurs by the dumping of
radioactive waste from nuclear power plants into water bodies
and soil.
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11. POLLUTANTS OF ENVIRONMENT
• Any substance which causes pollution is called a pollutant.
• A Pollutant may thus include any chemical or geochemical
(dust, sediment, grit etc.) substance, biotic component or its
product, or physical factor (heat) that is released intentionally by
man into the environment in such a concentration that may have
adverse harmful or unpleasant effects.
• Also defined as “any solid, liquid or gaseous substance present
in such concentration as may be or tend to be injurious to the
environment.”
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12. Types of Pollutants
The various principal pollutants which pollute air, water and land
are as follows:
1. Deposited matter: Smoke, tar, dust, etc.
2. Gases: Oxides of nitrogen (NO, NO2), sulphur (SO,), carbon
monoxide, halogens, (chlorine, bromine, iodine)
3. Acids droplets: Sulphuric acid, nitric acid etc.
4. Fluorides
5. Metals: Mercury, lead, iron, zinc, nickel, tin, cadmium,
chromium etc.
6. Agrochemicals: Biocides (like pesticides, herbicides,
fungicides, nematicides, bactericides, weedicides etc. and
fertilisers.
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14. Classification of pollutants
1. Classification of pollutants on the basis of nature
i. Pollution caused by gaseous wastes –
Eg. CO, CO2, SO2, NO2, O3, Smog gases, etc.
ii. Pollution caused by liquid wastes-
Eg. Acids, Alkalies, Poisonous substances,
Pesticides, Herbicides, etc.
iii. Pollution caused by solid wastes-
Eg. Garbage, Rubbish, Ashes, Construction
wastes, Dead animals Waste, Agricultural waste, etc.
2. Classification of pollutants on the basis of decomposition
i. Non degradable pollutants
ii. Degradable pollutants
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15. AIR POLLUTION
• It may be defined as any atmospheric condition in which
certain substances are present in such concentrations that they
can produce undesirable effects on man and his environment.
• Air Pollutant is any solid, liquid or gaseous substance present
in the atmosphere in such concentration, as may be or tend to
be injurious to human beings or other living creatures or plants
or property or environment.
• These substances include gases (sulphur oxides, nitrogen
oxides, carbon monoxide, hydrocarbons etc.), particulate
matter (smoke, dust, fumes, and aerosols), radioactive
materials and many others.
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16. • Most of these substances are naturally present in the
atmosphere in low (background) concentrations and are usually
considered to be harmless.
• Thus, a particular substance can be considered an air pollutant
only when its concentration is relatively high compared with
the background value and causes adverse effects.
• These pollutants are dispersed throughout the world's
atmosphere in concentrations high enough to gradually cause
serious health problems. Serious health problems can occur
quickly when air pollutants are concentrated.
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17. SOURCES OF AIR POLLUTION
• Sources of air pollution are natural as well as anthropogenic
source
1. Natural source:
i. Volcanoes: Volcanic activity produces smoke, ash, CO2, SO2
etc.
ii. Dust: Windblown from areas with little or no vegetation
iii. Forest fires: forest fire created by natural causes result in the
formation of smoke, ash, dust, CO2, oxides of nitrogen etc.
iv. Wetland: Microbial action in wetlands result in significant
amounts of methane being formed and released into
atmosphere.
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18. 2. Anthropogenic sources
• include pollution resulted due to emission of substances into
the atmosphere by human activity.
• Some of the anthropogenic sources include:
i. Stationary point source: it is a single identifiable source of air
pollutant emissions.
Eg:- smoke stacks of furnaces, incinerators, fossil fuel
power stations
ii. Mobile sources: it includes emissions from motor vehicles,
marine vessels and aircraft
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19. iii. Evaporative sources: these are volatile liquids that, when not
completely contained in a tank or other container evaporate
and release vapour over time.
Eg: Fumes from paint, hair spray, varnish, aerosol sprays
and other solvents
iv. Controlled burn practices in agriculture and forest
management.
v. Waste deposition in landfills, which generate methane.
vi. Military resources, such as nuclear weapons, toxic gases,
germ warfare and rocketry.
vii. Fertilized farmland may be a major source of nitrogen oxides.
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20. CAUSES OF POLLUTION
• Huge increase in population
• Rapid industrialisation
• Rapid urbanisation
• Uncontrolled exploitation of resources
• Radioactivity
• Volcanic eruptions, forest fires etc.
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21. TYPES OF AIR POLLUTANTS
1) Classification based on type
a) Deposited matter- dust, smoke, fog, mists, fumes etc
b) Gases –oxides of sulphur, nitrogen, CO, Ozone etc
2) Classification based on position
a) Point source- large stationary source as powerplants
b) Area source- small stationary source like residential
building
c) Line source- mobile source with definite routes like
vehicles
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22. 3. Primary & secondary pollutants
• Primary pollutants, which are emitted directly from identifiable
sources
eg: a)Ash from a volcanic eruption
b)Carbon monoxide gas from motor vehicles
• Secondary pollutants, which are produced in the atmosphere
when certain chemical reactions take place among primary
pollutants
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23. The major primary pollutants include:
• Suspended particulate matter (SPM), such as smoke, dust,
fumes, mist and spray, traces of metals, like lead, cadmium,
copper, nickel, mercury and iron.
• Sulphur oxides (SOx) [SO2, SO3]
• Nitrogen oxides (NOx) [NO, NO2, N2O] Carbon monoxide
(CO)
• Carbon dioxide (CO2), a greenhouse gas
• Volatile organic compounds (VOC), such as CFC
• Allergic agents like pollens and spores and Radioactive
substances
• Certain less important primary pollutants are H2S and HF and
other fluorides, methyl and ethyl mercaptains etc., which are
usually rarely found in our atmosphere, although if present, may
prove quite harmful.
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25. Secondary pollutants
• Secondary pollutants are not directly emitted.
• they form in the atmosphere by chemical interactions among
primary pollutants and normal atmospheric constituents.
• The primary pollutants often react with one another or with
water vapour, aided by sunlight to form secondary pollutants.
• Major Secondary pollutants include:
Sulphuric acid (H2SO4)
Particulate matter formed from gaseous primary
pollutants
Peroxyacetyl nitrate (PAN) Formaldehydes etc.
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27. PHOTOCHEMICAL REACTIONS TAKING
PLACE IN ATMOSPHERE
• Molecules in the atmosphere are continually moving and
colliding with one another, (kinetic-molecular theory).
• The atmosphere is also continually illuminated during daylight
hours.
• As a result, absorption of light energy by atmospheric
molecules can cause photochemical reactions, reactions that
would not occur at normal atmospheric temperatures in the
absence of light.
• Such reactions play an important role in determining the
composition of the atmosphere itself and the fate of many
chemical species that contribute to air pollution.
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28. FORMATION OF GROUND LEVEL OZONE (𝑶𝟑) VOC –
VOC: Volatile Organic Compounds(eg. CFCs)
RO2 represents any of a number of chains of organics with an O2
attached (replacing H in the original chain)
hv: sunlight
M- foreg. CO + 2O2 -> CO2 + O3
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29. PRIMARY AIR POLLUTANTS
1. OXIDES OF SULPHUR
• Sulphur dioxide (𝑆𝑂2) is the basic air pollutant among all the
oxides of sulphur
• 𝑆𝑂2 mainly originates in atmospheric air from the refineries,
chemical plants, smelting operations and burning of fossils
• Open burning of garbage as well as municipal incineration
plants may also emit 𝑆𝑂2 in the air
• 𝑆𝑂2 is an irritant gas and when inhaled affects mucous
membranes
• It increases the breathing rate and causes oxygen deficits in the
body leading to bronchial spasms in some affected persons
• Patients of asthma are very badly affected by this pollutant
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30. • Some quantity of atmospheric 𝑆𝑂2 may oxidize to form Sulphur
trioxide (𝑆𝑂3), which when inhaled, may dissolve in the body
fluids to form sulphuric acid (𝐻2 𝑆𝑂4), which is a very strong
corrosive acid.
• 𝑆𝑂3 thus causes high and worse irritation even at lower
concentrations, leading to severe broncho-spasm
• 𝑆𝑂2 is also responsible for acidity in fogs, smokes and in rains
and hence is the major source of corrosion of buildings and
metallic objects
• The new revised Indian ambient air quality standards prescribes
the permissible maximum annual average concentration of 𝑆𝑂2
for residential areas as equal to 50 µg/𝑚3(approx. 0.019 ppm at
200 C)
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32. 2. CARBON MONOXIDE (CO)
• CO is a colourless, odourless and toxic gas produced due to
incomplete combustion of organic materials like coal, natural
gas or wood
• Vehicular exhausts are the single largest source of CO as the
number of vehicles are increasing day by day
• Poorly maintained vehicles and those having inefficient engines
without pollution control devices emits the greatest amounts of
CO
• CO possesses about 200 times affinity for blood-haemoglobin
than oxygen
• Hence when inhaled CO replaces 𝑂2 from the haemoglobin and
forms carboxy-haemoglobin which is of no use for respiratory
purposes.
• CO inhalation impairs normal oxygen transport carried out by
blood 32
33. • low levels of CO inhalations may produce symptoms like
headache, dizziness, reduction in reaction time etc.
• Higher levels of CO inhalations may cause nausea, heart
palpitations, difficulty in breathing etc.
• In extreme cases it causes death
• Presence of CO in pregnant woman’s blood causes still births
and deformed offspring
• The new revised Indian ambient air quality standards prescribes
the maximum permissible concentration of CO, on hourly
weighted average basis as 4mg/ 𝑚3(3.6 ppm) for residential
areas
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35. 3. OXIDES OF NITROGEN(𝑵𝑶𝑿 )
• Oxides of nitrogen are produced either in the production of
nitric acid or in the automobile exhausts and as the effluent of
power plants.
• Out of the seven oxides of Nitrogen (𝑁2𝑂, NO, 𝑁𝑂2, 𝑁𝑂3
𝑁2𝑂3 , 𝑁2𝑂4, 𝑁2𝑂5) only nitric oxide and nitrogen dioxide are
classified as the main pollutants.
• All the oxides of nitrogen are collectively known as 𝑁𝑂𝑋
• Atmospheric nitrogen may combine with oxygen at high
temperature to form nitric oxide(NO) which is harmless at low
concentrations
• high concentrations NO may cause asphyxiation and
respiratory discomfort, because it combines at about 3 lakh
time faster with haemoglobin than oxygen.
• Larger concentrations may cause quick deaths.
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