Download v-environmental-pollution

Unit -5
Environmental Pollution
Definition:Environmental pollution is defined as “unfavorable alteration of our surrounding such as large
byproducts released by human things to the environment i.e., large particle harmful for human
and living organisms.
The introduction of substances by man into the environment liable to cause,
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Harm to living resource and ecological system.
Hazards to humans.
Damage to structure.
Interference with legitimate uses of the environment.
Pollution:It is a material which is present in excess of the natural concentration as a result of human
activity and process a bad effect upon the environment when assessing the problem a pollutant
mean posed. It is desirable to evaluate.
a.
b.
c.
d.
Tendency for bio accumulation.
Short and long term toxicity.
Dispersion properties.
Reaction (chemical) and break down or interaction product.
Source:It is the material or activity which releases the pollutants.
Receptor:It is something that is affected by the pollutants.
Sink:It is the store where the pollutant is received and stored for a long time.
Different types of pollution:There are different kinds of pollution that affect the environment is:
1. Air pollution
2. Water pollution
3. Soil pollution
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Marine pollution
Noise pollution
Thermal pollution
Nuclear pollution
Air pollution:It is defined as the presence of one or more pollutants in outdoor atmosphere in such quantities
and of such duration which might be injurious to human, plant or animal life. These pollutants
mean unreasonably interfere with comfort life or the conduct of business.
Every individual person breathe approximately 20000 times per a day, inhaling above 15-22
KGs of air daily, so air pollution is most crucial from the public health point of view.
Case of air pollution:i.
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Population increase.
Industrialization
Urbanization
Automobiles
Natural phenomenon like volcanic eruption, radioactivity etc.
This type of air pollution is due to outdoor sources but there is indoor air pollution also arising
from burning of coal, wood, animal dung and crop resides used for cooking and heating
purposes.
CO(carbon monoxide):This is colorless gas is released by automobiles due to inefficient combustion of carbon fuels.
This is a poisonous gas also released during mining operations.
CO2(carbon dioxide):This is also released during combustion of fossil fuels by automobiles and industries. This is
predominant greenhouse gas whose concentration is in atmosphere has been increasing with the
rapid industrial growth. The annual growth rate of 0.8 ppm during 1960’s has increased to 1.5
ppm during 1990’s.
Industrial countries contribute nearly 60% of total emission of CO2. It is life time, in the
atmosphere is around 100 years.
NO(nitrogen oxide):There are six known nitrogen oxides; nitric oxide and nitrogen dioxide are known pollutants.
These are released during burning of fossil fuels.by industries and automobilesthough
automobiles are the main contributor of these gases. They are also released during acid
manufacturing, the decay of agricultural waste and burning of wood.
SO2(sulphurdioxide):This is produced during the combustion of coal and fuel. It is a suffocating gas and poisonous.
The thermal power plants use coil as fuel release most of sulphurdioxide into the atmosphere.
Particulate matter:This is absorbed as suspension in air mostly consisting of dust, ash and smoke which are
chemically stable. These pollutants are dispersed in the atmosphere and diffused by air current,
but their composition remains unaltered. Burning of coal, in the power and steel plants are the
main sources of particulates, through automobiles and smelters also contribute.
Hydrocarbons:These are organic gases composed of carbon and hydrogen, insufficient conversion of fuels,
produce these gases. They react with nitrogen and oxygen through photochemical reaction. In the
presence of sunlight and produce small ‘smog’. Smog is noticed in mostly in cities as a brown
cloud hanging in air.
Ozone (O3):Smog contains ozone.in the lower atmosphere i.e., troposphere it act like a poison and pollute air.
But in stratosphere ozone exists in mining place and filters, ultraviolent radiation coming from
the sun which is harmful to life and earth. Ozone is produced as follows SO2 and NO2 in the
atmosphere break in the presence of sunlight and the atomic oxygen is released. This atomic
oxygen combines with an oxygen molecule to form ozone.
Effects of air pollution:CO and H2s which are suffocating pollutants effect hemoglobin and respiratory system.
SO2 and NO2 irritate lungs and affect the lining of respiratory track.
Ozone irritates eyes and nose.
Smog causes sight and respiratory problems.
Particulates depending on the type and concentration may cough and difficulty to breath
and long term may develop brown chit ties and lung cancer.
6. The toxic pollutant lead released by vehicles which use lead petrol affects gastroindicial
track and weaken the functioning of kidneys and liver.
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7. 2.5 billion People suffering from high levels of indoor pollution, more than 1. 1 billon
people suffer from outdoor pollutionannually.
8. Air pollution reduce food production because photosynthesis mechanism is weekend by
high level of air pollution.
9. Pumpkins, cotton, wheat and apples are very sensitive to slphr dioxide.
10. Tomato’s, potato’s, beans and tobacco are sensitive to ozone.
11. Apricots, tulips, pine to fluorides and so on.
12. According to W.H.O about 7 lakh deaths to be avoided in developing countries, these 3
major air pollutants Co, Suspended particles and lead were brought down to safe level.
Control of air pollution:The minimum standards of environmental quality and the permissible levels of pollutants in the
atmosphere should be made known by displaying in industrial areas and at important public
place in cities.
In general, dilution is the solution particulates remove of poisonous gas and clean air legislation
may help in the control of air pollution.
The following measures are needed to control air pollution in industrial center.
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The emission rate should be restricted to permissible level by each and every industry.
Incorporation of air pollution control equipliant in the design of plant layout must be
made monitory.
Continuous monitoring of the atmosphere for the pollutants should be carried out to
know the emission levels.
Water pollution:Water is a vital resource of life. Pollution of water is altering of its quality so that it becomes
unfit for the purpose it is used.
It occurs when chemicals (or) nutrients (or) waste enter faster than they can be removed by
natural process.
The pollutants includes sewage, industrial chemicals and effultants, slit, oil and other
wastage. Besides chemicals from the air dissolve in rain water and fertilizers, pesticides and
herbicides soaking from the land also pollute water.
Causes of water pollution:Water pollution is due to two reasons.
a. Point source:
Ex:-drainage pipes, ditches, sewer out fall
b. Non-point source:
Ex:- runoff, atmosphere deposition
a. It may be caused by biotic and abiotic contamination.
b. It results from either natural resources or artificial resources.
c. The natural phenomenon for example drought blender’s water level to
decline in allowing salt water.
d. Population growth and unplanned urbanization also contribute to
pollution of water. Factories and mines release large quantities of toxic
chemicals, organic wastage, heavy metals, heated effluents, inert waste
and radioactive waste causing water pollution.
e. Toxic chemicals are not easily degradable by biochemical DDT and
mercury poisonous and if contacted by plants (or) animals may prove
fatal.
f. Organic waste is referred to rotting organic matter which generatesfoul
smell.
g. The pollution level is indicated by a parameter, BOD ( biochemical
oxidant demand).
Effect of water pollution:i.
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The immediate effect is scarcity of safe water for drinking purpose. Nearly 1 billion
people world wide lack access to safe drinking water. In many large cities, in the
developing countries, the drinking water supply is polluted. In south eastAsia, only 550
million people have accessed to safe drinking water.
Water borne disease, also known as dirty water disease result from consuming
contaminated water. Around 2.3 billion people globally suffer from the disease.
The polluted water contains, water borne disease producing organism which can be virus
(or) bacteria (or) protozoa. Most of the diseases are diarrhea disease, but typhoid,
infections hepatitis, and Para typhoid are also caused.
An estimated 12 million deaths occur every year, 5 million of them due to diarrhea
disease. Most of these victims are children from developing countries. Around 60 to 70
working days are lost in a year an averagede to water borne disease.
Water pollution affects the food production also. Agriculture itself pollutes water due to
positive uses of fertilizers, pesticides and herbivorous.
The effect of water pollution on fisheries is very severe because the depletion of in
oxygen in the water due to the presence of toxic and organic waste.
The chemical, plastic and paper industries release wastage contain mercury levels in
these waste are more than normal, some type of fish in coastal waters contain more
mercury in their bodies. When people consume this fish they become seriously ill (or)
die.
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Even industries have problem with polluted water. A generally use soft water most of the
applications and treating contaminated water to make it fit for use become coasty.
The waste heat in the water enables for industrial cooling purpose.
Control of water pollution:a. The industries which have tried to reduce waste by recycling and redesigning production
process and products have found that such measures actually save money.
b. Providing sanitation and waste treatment facilities is the second approach. Sanitation is
one of the environmental quality issues linked with population growth and urbanization.
c. The sanitation facilities are imperative as the cities grow, practically in developing
countries. Industrial and community sanitation along with control and treatment of human
waste and industrial waste necessary to reduce water pollution.
d. More sewage water treatment plants should be installed in cities and industrial belts.
e. In India, most of the cities and industrial units discharge sewage into nearby rivers (or)
surface water bodies. More than 70% of water bodies in the country are polluted.
f. River Ganga is the most polluted river. Nearly 130 industries and around 100 towns and
cities located on the bank of the river keep discharging effluents and sewage into the
river.
g. Other rivers are also contaminated due to the release of effluents from fertilizers and steel
milk, sugar factories, paper and pulp industries.
h. The “national environmental engineering institute”, Nagpur has developed innovative
methods to that treat sewage and industrial effluents using filtration techniques chemical
based.
i. The ministry of environment and forest, government of India, has developed industry
oriented standards called minimum national standards(MINAS) and enacted water
(prevention and control of pollution) act.
Soil pollution:Soil pollution can be define as the introduction of the substance biological organisms (or)
energy into the soil that will lead to a change in quality of the soil, so that plant growth and
animal health is adversely effected.
Causes of soil pollution:It is caused due to direct and indirect sources.
The main reasons of soil pollution are briefly discussed below:
1. pesticides:These are the chemicals which are used by farmers to protect their crops. Thus, the
soil becomes infertile. They accumulate and magnify to the food chain and interfere
with the calcium metabolism of birds. As a consequence, birds lay fragile, thin
shelled eggs. High concentration of pesticides gets accumulated in fatty tissues of
free organisms. When predators eat these prey organisms, they also get killed.
2.Fault agricultural practices:
a) Unskilled irrigation:- water logging may occur when the drainage system of the
agricultural system is not maintained scientifically water logging closes the
passage of air in the soil, stops the growth of soil organisms and makes the soil
barren.
b) Shifting cultivation:- the forest burned to use the land for cultivation. However,
this practice exposes the soil for erosion.
c) Injudicious use of chemical fertilizers:- use of inorganicfertilizers increases the
nutrient contamination. The microbes of the soil reduce the nitrogen to nitrite
ions, which entered the animal body through food or water. The lateral cannot
carry oxygen any more so ultimately animal dies.
3.Solid waste from homes and industries:chemical, petroleum and metal related industries, dry cleaners and gas stations
produce hazards waste such as oil, battery me organic solvents. This hazards waste
contaminates soil and water resource.
4.Acid rain:It converts neutral soil to acidic one.
Effects of soil pollution:Harmful effects of soil pollution are briefly described below.
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Production in the fertility of soil.
Objection in the public passengers (road, railway lines etc.,) by solid wastage.
Contamination of underground and surface drinking water.
Fluorosis occurs as a result of contamination of fluoride containing maize
crops. The fluoride is observed by the crops from the fluoride contaminated
soil.
Emission of toxic gases is determenental to health.
The unpleasant smell and spread of insects cause inconvenience to people.
Poisoning of ecosystem take place by soil pollution.
Soil erosion occurs due to shifting cultivation.
Control of soil pollution:The land pollution can be controlled by following methods.
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Planned a forest station helps in prevailing soil erosion.
Use of bio fertilizers and natural pesticides help in minimizing uses of chemical
fertilizers and pesticides.
The principles of three R’s namely recycle, reuse and reduce help in minimizing
generation of solid waste.
Formulation and effective implementation of stringent pollution control legislation also
help in controlling soil pollution.
Proper disposal methods must be employed. For example, compositing of biodegradable
solids and incineration of non biodegradable solids and incineration of non biodegrable
solid should be done.
Proper treatment of liquid waste from industries and mines must be done.
Fault sanitation practices must be improved.
Polluted soil can be treated by bio remediation. It uses micro organisms to break down, or
degrades hazards substances into less toxic or nontoxic substance.
Marine pollution:This is also known as ocean pollution. Direct or indirect by man the substance into marine
environment resulting in such deleterious effects as harm to living resources, hazards to human
health (or) hindrance to marine activities and reduction of amenities is the definition given to
marine pollution by ICO (International Oceanography Commission).
Causes of marine pollution:1.Half of the world population live near to coastal lines and derive many benefits from the
coastal zones and oceans.
2.The coral reefs which are the most productive ecosystem offer many benefits to people, for
example
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Reefs support more than one million species.
They provide feeding, breeding and nursery areas to fish
They offer medicine.
They act as buffer to ocean waves and protect coastal lines from storms and so on.
3.The coral reefs have been valued at 47000 US $ per square meter of shore lines for their
protection function alone. The coastal wet lands provide habitats for over 2000 species of fish
and plants.
4.The coral reefs are threatened by
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The sediment from deforestation carried by the runoff.
The agricultural and industrial chemicals rich in through river discharge.
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The boat anchor’s and careless drivers.
Rising ocean temperature.
5. the wet land have been destroyed or degraded by conversion to agricultural lands (or) fish
farms (or) the urban expansion (or) for industrial development. The sea grass beds are also
victims of various kinds of coastal development activities.
6.oil spills from ships and oil refiners normally situated on coastal areas are another source of
pollution. When the floating of oil slicks extend over very large areas, detergents are used to
cover them, which become another source of pollution.
7.mention an example, river ganga is estimated to carry 1.5 billion tons of sediment due
todeforestation and intensive farming in India, Bangladesh and Nepal through whichit flows in
bay of Bengal. India is estimated to see 55000 metric tons of pesticides annually above 25% of it
is carried to ocean.
Effects of marine pollution:1.the coastal eco system which serve as hatcheries for fish , are being exposed to heavy pollution
resulting in destruction of 90% of world’s fish catch.
2.the rapid population growth has boosted the demand for fish while the fish catch has decreased
due to the decline of marine habitats.
3. due to presence of ocean currents and the pollutants are not localized but transported to all
corners of the world.
4.the role of ocean in circulating cold and warm water which help to regulate climate and to
protect against extreme temperature luxation is also affected due to pollution.
5.the oil slacks kill sea birds and other species and the detergents affected the sea plants and the
organic life.
Control of marine pollution:Controlling marine resources and marine pollution are difficult jobs. 177 nations in the world are
endowed with coastal lines, but only 92 nations have coastal management plans. The world wide
fund for nature and wild conservation union suggested a plan for sustainable management
involving 6 principles.
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Plants for conserving marine biodiversity must take account of human needs.
People should be educated about marine ecosystem and benefits offered by them.
Local communities must be involved in protecting and managing their coastal resources.
Source and economic incentives must be offered for conserving and sustainable use of
marine resources.
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The fact that all the oceans in the world are connected must be reflected in the policies.
Government must manage their own water by extending cooperation to the neighboring.
Noise pollution:This is known as sound pollution. It is the uneasy, unwanted and desire sound produced by
traffic, industrial units, aero planes and similar sources.
Causes of noise pollution:i.
It exists mostly in densely polluted areas like cities and industrial complexes, railway
stations, bus station, air ports, shopping complexes and other commercial zones are
the sources of noise generation. Television, radio, kitchen, gadgets produce noise in
the house. Even music can be a noise when it is loud and harsh.
In industries huge machines running at high speed produce sounds of difficult nature
with different intensities. This sound contribute to noise pollution.
In public places such as temple, mosque, church and commercial centers and
functions such as meetings and marriages, loudspeakers are used indiscriminately
creating noise of high intensity.
The missionary used at construction sites create noise of irritating nature.
Automobile tracks and buses produce noise from engine, blowing horns and
deflecting defective silencer pipe.
Sound levels are measured in nits of decibels.
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Effects of noise pollution:i.
Effect of noise pollution on the health of people is equally disastrous. The
cytological effects are losses of hearing and noise induced diseases.
Hypertension, stress diseases are also cased by noise pollution. Increase of noise
potion cases faint, burning of skin and omitting.
It also affects the behavior aspects irritation, nervousness, headache are some of
the affects notices in people working in factories that produce a lot of noise.
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Control of noise pollution:i.
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Noise pollution can be reduced through source reduction and usage of silence
besides increasing vegetation.
The provinces listed in the environmental protection and should be strictly
implemented.
The use of loud speakers in public places should be regulated. The buses and
trucks should be subjected to periodic al servicing like pollution test to
eliminate the generation of sounds from engines etc.,
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The factories should equip all the big machines with noise reduction gadgets.
The walls, doors and sailing should be covered with sound proof materials and
the work must be provided with ear protection in industrial unit.
Residential complexes should be avoided nearer to airport, railway stations
and bus stations and busy industrial areas.
Plantation also help to absorb and screen noise in areas where excessive noise
is generated.
Thermal pollution:Thermal pollution is the pollution created, when the waste heat a byproduct in many industrial
process is released into water bodies such as lakes and rivers.
Causes of thermal pollution:i.
ii.
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Many heavy industries se water cooling purpose during manufacturing process. Cold
water is run through the cooling cycle and discharge at a higher temperature.
For example, metallurgical plants, chemical and pharmaceutical industries, paper and
pulp industries, petroleum products and plastic industries are sum of the major industries
that utilize fresh cool water and release as waste hot water. Thermal power plants are the
major consumers of fresh water and probably major contributor to thermal pollution.
It is estimated that a thermal power plant requires about 40 gallons of water for producing
1KW hour power, and a nuclear plants require around 55 gallons for KW hour. All this
waste water is released into near by water bodies.
Effects of thermal pollution:i.
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The hot water released into water bodies rises the temperature and increase the biological
growth rate and oxygen demand while for the same time reducing oxygen diffusion.
The dissolved oxygen levels drop drastically affecting the aquatic life, particularly fish
population. The water quality also gets changed. If the water bodies are already
contaminated with chemical pollutants, the addition of thermal pollution enhance the
toxicity because the presence of chemical pollutants also affects the dissolved oxygen in
water.
The decrease in the oxygen content in the water bodies de to thermal pollution depends
on the temperature of the released water. The survival of fish and other aquatic life
depending on the dissolved oxygen levels in water.
Control of thermal pollution:i.
Technological improvement in thermal power plants reduce the generation of waste heat.
Cooling towers are set to transfer heat from the water to atmosphere by evaporation,
preventing thermal pollution.
ii.
The ponds are so designed that the heat water is released for the shallow end above 1 to 2
mts depth which gets cooled by natural cooling and the cooled water is drawn from the
bottom of the pond at the other end above 15 mts deep for cooling purpose.
Thermal pollution could be significantly reduced if the heat is directly converted into
energy.
Certain commercially available fish cultures are grown in hot water. Hence aqua culture
could be developed.
Desalination of sea water is also attempted using the heat available in the waste water.
Some of these measures have to fully developed to utilize waste heat, a useful byproduct
of industrial activity.
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Nuclear hazards (or) radioactive pollution:Risk and danger to human health (or) the environment pose by radiation emanating from the
atomic nuclei of given substance, or the possibility of an uncontrolled explosion originating
from a fission or fission reaction of atomic nuclei.
Causes of nuclear hazards:i.
ii.
iii.
Radioactive substance are present in a nature, they undergo natural radioactive decay
in which unstable isotopes spontaneously give out fast moving particles, high energy
radiation (or) both at a fixed rate until a new stable isotope is formed.
Α particle can be interrupted by a sheet of paper β particle can be blocked by piece of
wood or a few mm of aluminum sheet. Γ rays can pass through paper and wood but
can be stopped by concrete wall, leads slabs (or) water sources of radioactivity natural
sources.
Sources of radioactivity natural sources cosmic rays from outer space radioactive
random-222 soil, rocks, air, water and food. Anthropogenic sources, nuclear power
plants, nuclear oxidants, x-rays, diagnostic kits, test laboratory’s.
Effects of nuclear hazards:i.
ii.
Genetic damage is caused by radiation, this induce mutation in DNA there by affecting
genes and chromosomes, the damage is often seem in the offspring and may be
transmitted up to several generations. Somatic damage is includes burns, breast, lungs,
skin.
Many scientists are of the view that due to body’s ability to repair some of the damages,
the adverse effects of radiations are observed only beyond a threshold level. Other group
believes even a small dose of radiations over a period of time may cause adverse affects
damage caused by different types of radiations depends on the penetration power and the
presence of source inside or outside the body.
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Thus, they are more dangerous and cannot penetrate the skin to reach internal organs,
greater treat is posed by radio active isotopes, with intermediate of lives as they have long
time to find entry inside.
Control of nuclear hazards:Control of nuclear pollution setting of nuclear power plants should be carefully done after
studying long term and short term effects proper disposal of waste from laboratory involving
the use se of radio isotopes should be done.