5 Pollution and its Factors part 3
Effect of Noise Pollution
1. Constant noise affects a man physically and mentally. Physical effects include
blood vessels to contract, skin to become pale, muscles to constrict and rise in blood
pressure leading to tension and nervousness.
2. High intensity sound emitted by industrial plants, bottling machines, supersonic
aircrafts, when continued for long periods of time not only disturbs but also
permanently damages hearing.
3. Offices, industries and crowded places where constant noise prevails can produce
temper tantrums, headaches, fatigue and nausea.
4. Loud and sudden noise affect the brain. Intermittent noise leads higher incidence
of psychiatric illness and also a danger to health of pregnant mothers and small
infants.
5. Noise has harmful effects on nonliving materials too, e.g. cracks develop under the
stress of explosive sound.
Control of Noise Pollution
Following methods can control noise pollution:
1. Limited use of loudspeakers and amplifiers.
2. Excursing control over noise producing vehicles.
3. Industrial workers should be provided with ear plugs.
4. Delocalisation of noisy industries far away from dwelling units.
5. Within a radius of 10 miles of airport, no buildings or factories should be allowed.
6. Plants and trees should be planted all around the hospitals, libraries and schools
and colleges.
7. Personal protection against noise can be taken by using, cotton plugs in the ear.
Radiation
The radiations from the atomic blasts cause several health hazards. The radiations
carry high energy and remove electrons from atoms and attach them to other atoms producing
positive and negative ion pairs. Hence, they are known as ionizing radiations. The ionization
property of these radiations proves to be highly injurious to the protoplasm. The ionizing
radiations of ecological concern are classified as follows:
Corpuscular Radiations
These consist of streams of atomic or subatomic particles, which transfer their energy
to the matter they strike.
(i) Alpha particles
These particles are large and travel few centimeters in the air. These cause large
amount of local ionization.
(ii) Beta particles
These are small particles characterized by having high velocities. They can travel a few
meters in space. These are capable of entering into the tissues for few centimeters.
Since alpha and beta particles have low penetration power they can produce harmful
effects only when absorbed, ingested or deposited in or near living tissues.
(iii) Electromagnetic radiations
Electromagnetic radiations include waves of shorter wavelengths. These are capable of
traveling long distances and can readily penetrate the living tissue. These include gamma
rays. These can penetrate and produce effect even without being taken inside.
Other Types of Radiations
Besides radioactive radiations, some other radiations are also present in the atmosphere
(i) Neutrons
These are large uncharged particles, which do not cause radiation by themselves, but
they produce radioactivity in non-radioactive materials through which they pass.
(ii) X-rays
These are electromagnetic waves very similar to gamma rays, but originate from the
outer electron shell of radioactive substances, which are not dispersed in nature.
(iii) Cosmic rays
These are radiations from the outer space, which contain alpha and beta particles
together with gamma rays.
Sources of Radiations
The radiations are produced from the radioactive elements, which are known as
radionuclides or radioactive isotopes, e.g. Uranium. Radium, Thorium, and Carbon-14. These
contribute to background radiation. But isotopes of certain metabolically important elements
like Carbon-14, Cobalt-60, Calcium 45, Iodine-131, Phosphorus-32, etc. are not ecologically
harmful but are used as tracers. The third category of radionuclides comprises of fission
products of uranium and certain other elements. These are cesium, strontium, and plutonium
etc.
Biological Effects of Radiation
The effects of radiation have revealed that acute doses are found to be deleterious and
may kill the organisms, whereas the increase in radiation in biological environment leads
to different kinds of mutations. The effects of Cobalt-60 or Cesium-137 gamma radiations
have now been studied on communities and on ecosystems at different places. The research
concludes that Irradiations eliminate varieties in species. The sensitivity of cells, tissues and
organisms to radiation varies. The cells with larger chromosomes are more sensitive.
Herbaceous communities and early stages of succession are resistant than the mature forest.
Nuclear Fall Outs or Radioactive Fall Outs
The atomic blasts not only produce the local ionizing radiations at that time but the
radioisotopes produced as a result of explosion enter the atmosphere and continue to fallout
gradually over broad geographic areas for a very long time. These are known as nuclear
fallout or radioactive fallout. These are dangerous for life as they also produce ionizing
radiations.
Biological Effects of Fall outs
The fallout of radionuclides combines with various metals and dust and from colloidal
suspension combines with organic compounds to form complexes. The smaller particles of
radionuclides adhere tightly to the leaves of plants and produce radiation damage to leaf
tissue besides entering the tissues also. Through grazing animals these enter the food chain
directly at the primary consumers level. Radionuclides, which combine with organic
substances, enter the food chain through producer tropic level. Therefore, the radionuclides
fall out manages to enter the body of all living organisms. Radioactive Strontium-90 poses
a health hazard in human beings and other higher vertebrates. It continues to deposit in
the bones and causes bone cancer and leukemia. Radioactive Cesium-137 is known to cause
irreversible genetic changes in different organisms. The fallout radiations do cause changes
in the genetic constitution of organisms, resulting in gene mutations and chromosomal
aberrations. Their considerable, doses may kill, cripple and alter the animals and plants in
the areas.
Control of Radiation Pollution
Following measures can help in controlling the radioactive pollution:
(i) Workers in nuclear plants should be provided with nuclear gadgets and safety
measures against accidents.
(ii) Leakage of radioactive elements from nuclear reactors, laboratories, transport,
careless handling and use of radioactive fuels should be checked.
(iii) Level of radiation pollution should be monitored regularly in risk areas.
(iv) Disposal of radioactive wastes deserves special attention.
Case studies
Hiroshima and Nagasaki Episode
The tale of Hiroshima and Nagasaki is a painful experience. It is for the first time that
an atomic bomb has been exploded over human population. The incident took place on
August 6,1945 at 8:15 a.m. The bomb with an approximate temperature of around 100
million 0°C was exploded on a fine morning in Hiroshima (Japan). The temperature of the
city hiked like anything, almost like an oven. After three days, Nagasaki too suffered the
ravages of a nuclear attack. More than 1,00,000 people were reported to die just after the
event took place. Since radiations from nuclear elements remain active even after, the
generations to follow up also suffered from various diseases. Even the babies in the mother’s
womb were affected and a few perished. Blindness, deafness, skin diseases and cancers,
distortion of bones and other parts became the fortune of human civilization.
Chernobyl Accident
This incident took place in Ukraine on April 26, 1986. There was a Chernobyl nuclear
power plant in Ukraine after which the event has been named. Approximately four million
people had been reported to suffer from the accident. The accident contaminated neighboring
environment up to several kilometers. The sites were evacuated and resettlement was done
for the affected people. The radiations released affected ground water and surface waters,
affecting large areas of Europe. 131 Iodine and 137 Cesium are the most dangerous amongst
the 20-odd radioactive elements released during Chernobyl disaster. As per the Soviet Health
Ministry, 31-persons died shortly after the disaster. Of the 276,614 people who worked for
rehabilitation and cleaning operations, a total of 1065 died by the end of 1990.
Marine Pollution
All river drainages end up in the seas. On the way to sea, rivers carry large amounts
of sewage, garbage, and agricultural discharge, biocides, including heavy metals. Besides
this discharge of oils and petroleum products and dumping of radionuclides waste into sea
also cause marine pollution. Huge quantity of plastic is being added to sea and oceans. Over
50 million lb plastic packing material is being dumped in sea of commercial fleets. Many
marine birds ingest plastic that causes gastro-intestinal disorders. The chemical principle in
PCBs causes more damage as thinning of eggshell and tissue damage of egg. Radionuclide
waste in sea includes Sr-90, Cs-137, Pu-239, and And Pu-240.
The pollutants in sea may become dispersed by turbulence and ocean currents and
finally becomes a part of food chain. Bioaccumulation in food chain may result into loss of
species diversity. The pollution in Baltic sea along the coast of Finland, took place largely
from sewage and effluents from wood industries. This pollution effect brought changes. in
species diversity in the bottom fauna. In less polluted water there was rich species diversity,
which tended to decrease with increasing pollution load. In heavily polluted areas, macroscopic
benthic animals were absent, but chirognomy larvae occurred at the bottom. In marine
water the most serious pollutant is oil. Spill of oil or petroleum products due to accidents/
deliberate discharge of oil polluted waste brings about pollution. About 285 million gallons
of oil are spilled each year into ocean, mostly from transport tankers. Oil pollution causes
damage to marine fauna and flora including algae, fish, birds, and invertebrates. About
50,000 to 2,50,000 birds are killed every year by oil. The oil is soaked in feathers, displacing
the air and thus interferes with buoyancy and maintenance of body temperature.
Hydrocarbons and benzpyrene accumulate in food chain and consumption of fish by man
may cause cancer. Detergents used to clean up the spill are also harmful to marine life.
Thermal Pollution
The increase in water temperature by industrial units such as steel and iron factories,
electric powerhouses and atomic power plants may be called as thermal pollution. Some of
the industries generate their own power supply where water is used to cool the generators.
This hot water is released into the main stream, causing a warming trend of surface waters.
If the drainage is poorly flushed, a permanent increase in the temperature may result.
Many organisms are killed instantly by the hot water resulting into a high mortality.
It may bring other disturbance in the ecosystem. The eggs of fish may hatch early or fail
to hatch at all. It may change the diurnal and seasonal behaviour and metabolic responses
of organisms” It may lead to unplanned migration of aquatic animals. Macrophysics population
may also be changed. As temperature is an important limiting factor, serious changes may
be brought about even by a slight increase in temperature in a population. Heat stress
(5-1 one above the normal growing temperature of organism) induces expression of specific
gene families called heat shock genes, which lead to the synthesis of a new set of proteins
called heat shock proteins. Heat shock proteins have been found in every organism from
unicellular prokaryotes to multicultural organisms including Homo sapiens. Heat Shock
Proteins synthesis lead to acquired thermo tolerance, i.e. the ability of an organism to
withstand a normally lethal temperature. Thermo tolerant genotypes show adaptations at
various levels of organization besides showing qualitative and quantitative differences in
heat shock proteins as compared to the thermo sensitive genotypes.
Solid Waste Management
Environmental problems also include solid waste disposal. At all levels of development
human beings produce domestic wastes. These comprises of kitchen wastes, ashes from
fires, broken utensils and worn-out clothing. The industrial revolution leads to the
concentration of people in urban areas with very high population density. This resulted in
addition of new sources of wastes from shops, institutions and factories. In developed countries
services for the regular removal of domestic and trade wastes have been in operation for last
many years.
Many changes have taken place in our society. The character of the wastes has altered
with rising living standards, changes in retail distribution methods and fuel technology.
Grave environmental concerns have come up with rise in construction of new buildings,
supermarkets, and industrial wastes of many kinds. In the industrialized countries, therefore,
basic health and environmental problems have been solved in the storage and collection of
solid wastes, although major problems remain in regard to resource recovery and disposal.
The technology of wastes handling is now highly developed. The substantial sectors of
industry are engaged in the production of equipment with regard to removal of wastes.
Many institutions give technical training and support. However developing nations like
India are facing the problems of urbanization with high population densities. The developing
countries are aware of the importance of avoiding the environmental pollution. The quality
of urban environment is a matter of growing concern and the importance of solid wastes
management is increasingly being recognized
Sources and Characteristics
Solid wastes generally refer to describe non-liquid waste materials arising from domestic,
trade, commercial, industrial, agriculture and mining activities and from the public services.
Disposal of sludge’s (liquid waste) of some kind fall within the scope of solid waste
management. These arise primarily from industrial sources and from sewage treatment
plants. Solid wastes comprise countless different materials; dust, food wastes, packaging in
the form of paper, metals, plastics or glass, discarded clothing and furnishing, garden wastes
and hazardous and radioactive wastes. The method and capacity of storage, the correct type
of collection vehicle, the optimum size of crew and the frequency of collection depend mainly
on volume and density. Just as solid wastes comprise a vast number of materials, they arise
from a multitude of separate sources as well as many kilometers of streets upon which solid
wastes accumulate. Thus, the four main aspects of solid wastes management are: (i) storage
at or near the point of generation, (ii) collection, (iii) street cleansing, (iv) disposal.
The main constituents of solid wastes are similar throughout the world, but the
proportions vary widely. As personal income rises, paper increases, kitchen wastes decline,
metals and glass increase, total weight generated rises and the density of the wastes declines.
Clearly, the amount of work involved in refuse collection depends upon the weight and
volume of wastes generated and the number of collection points from which the wastes have
to be removed.
Health and environmental implications
Improper handling of solid wastes results in increased potential risks to health and to
the environment both. Direct health risks concern mainly the workers in this field, who
need to be protected, as far as possible, from skin contact with wastes. For the general
public, the main risks to health are indirect and arise from the breeding of disease vectors,
primarily flies and rats. More serious, however, and often unrecognized, is the transfer of
pollution to water, which occurs when the leach ate from a refuse dump enters surface water
or wastes, either in the open air, or in plants that lack effective treatment facilities for the
gaseous effluents. Traffic accidents can result from wastes accumulated and dispersed on to
streets and roads. They have caused death and injury to people in the surrounding areas.
There also persists the specific danger of the concentration of heavy metals in the food
chain. These metals can be taken up by the plants growing on land on which sludge has
been deposited, creating risks to the animals which graze and the humans who consume
these animals.
Economic implications
Labour and transport absorb the major part of the operating cost of solid wastes
management services. The level of mechanization that should be adopted for solid wastes
management systems relates directly to the cost of labour, as compared to that of plant and
energy. There is not much variation, worldwide, in energy or mechanical plant costs, but
there is wide variation in the range of labour costs. Thus, there are no universally applicable
solid wastes management systems. Every country must evolve indigenous technology based
on the quantity and character of the wastes, the level of national wealth, wage rates,
equipment, manufacturing capacity, energy costs etc. It is necessary to deploy a complete
set of technical skills, which derive from several professional disciplines. These include civil
and mechanical engineering, chemical engineering, transport organization, land use planning
and economics.
Refuse Collection
A refuse collection service requires vehicles and labour. For their efficient development,
three components are basic:
(1) Travel to and from the work area,
(2) The collection process, and
(3) The delivery process.
The use of large, widely spaced communal storage sites is usually a failure because the
demand placed on the householder goes beyond his willingness to cooperate. Communal
storage points should, therefore, be at frequent intervals, Madras and Bangalore provide
fixed concrete containers. They are fairly successful because they place reasonable and
acceptable duty on the residents, thus very little domestic waste is thrown in the street.
In another system of block collection, a collection vehicle travels a regular route at
prescribed intervals, usually every two days or every three days, and it stops at every street
intersection, where a bell is rung. At this signal the residents of all the streets leading from
that intersection bring their wastes containers to the vehicle and hand them to the crew to
be emptied. A crew of one or two men is adequate in number, as they do not need to leave
the vehicle.
Sanitary Landfill Disposal
Land disposal (burying of wastes) is the only approved method of disposal, which is
performed at a single site. Incineration, composting, and salvage are either a form of refuse
handling or processing. They are not complete methods of disposal, and they require disposal
of residue. Sanitary landfill can be defined as the use of solid wastes for land-reclamation,
a typical example being the restoration, by filling to the original level of man made surface
dereliction such as a disused surface, mineral excavation. Solid wastes may also be used to
improve natural features by raising the level of low-lying land to enable it to be used or
cultivation or industrial development. Thus, sanitary land filling has two essential features,
which differentiate it from crude dumping:
(i) Only sites that will be improved not degraded, by a change of level are selected.
(ii) Simple engineering techniques are used to control the manner in which the wastes
are deposited, so that dangers to public health and the environment are avoided.
Unfortunately most of the world’s wastes are disposed off by uncontrolled dumping
which blights the land for any future use and causes serious risks of water pollution and
vector breeding. Very few cities operate sanitary land filling to standards, which totally
control health and environmental dangers; most of those that do are in the industrialized
countries.
Control of Hazards
(i) Control over pathogens is dependent upon a rigorous policy of covering the wastes
soon after deposit. This serves both to isolate the wastes and to retain the heat,
which is quickly generated during aerobic decomposition.
(ii) The main source of insects will be the eggs of flies. Which have been deposited in
the wastes before they arrive at the site. Most of these will be buried deep in the
wastes and will succumb to the temperature increase.
(iii) Fire at a sanitary landfill can arise from innumerable causes, hot ashes in a vehicle
delivering wastes: a cigarette thrown by a worker; the sun’s ray though a fragment
of glass on the surface. With some kinds of wastes the consequence of fire may be
very serious and underground fires have been known that ultimately caused the
collapse of the surface into voids caused by the fire.
(iv) The pollution of static water, ditches, river or the sea occurs when a sanitary
landfill adjoins a body of water. The normal source of the leach ate causing this
pollution is rain falling on the surface.
Incineration
Open burning, barrel burning, and other related uncontrolled forms of burning have a
long history of use. Many liquid wastes and pathological wastes are best disposed of by
incineration. Originally, solid waste incineration was practiced to reduce the quantity of
refuse or disposal. After it was proven that heat could destroy most pathogens, incinerators
were used in hospitals for destruction of pathological wastes. With few exceptions, incinerators
are not “good neighbors,” and the environmental nuisances of dust. Noise and air pollution
have provoked communities to an anti-incinerator philosophy. To overcome this negative
community feeling is going to require that incineration prove its worth and that imagination
be used in the design of future units. Incineration of solid wastes yields the highest percent
of volume reduction except for Pyrolysis. Unlike a sanitary landfill, incineration of solid
wastes can be performed on the premises of apartments, supermarkets, departments’ stores,
and similar establishments.
Composting
Composting involves the biological stabilization of solid matter either under aerobic or
anaerobic conditions. The end product of composing is an organic material, which could have
beneficial value as a soil conditioner or plant mulch. In addition to producing a modified
solid waste material, which can be useful in land reclamation, composting does yield a
volume reduction of solid waste by about 40-60% of the compost able fraction pyrolysis
Pyrolysis is a thermal process where oxidation of the organic fraction is not allowed to
occur. Instead, the organic matter is evolved from the refuse with heat, leaving an ash
consisting mostly of carbon and any inorganic matter, e.g. metal and glass are not removed
before Pyrolysis. Some of the gases, which have been volatized, are condensed while the
remainder is burned to supply the heat (energy) needed to pyrolyze the material. Since
oxidation is prevented, the Pyrolysis process must be performed in an atmosphere of argon,
helium or nitrogen.
Role of an Individual in Prevention of Pollution
Which are the most viable, efficient and economical ways to eliminate pollution problems?
We very often see people blaming public and government sectors to control pollution through
controlling market mechanisms and government blaming people to avoid and check pollution.
Who would control whom? Many ecologists and environmental scientists believe in that
pollution problems can be overcome by using market mechanisms to reduce pollution rather
than rigid rules and regulations. However, on the other hand man should identify and gear
up his own potential to curb down pollution. Man could achieve this by identifying his own
role at individual level in prevention of pollution. This is possible through environmental
awareness, education and enlightenment.
Ways and means by which pollution problems can be greatly reduced at individual level
are:
1. Masses at personal level should determine to consume optimum level of resources,
which would lead a comfortable life. Because excessive resource consumption is in
someway related to pollution problems and hazards (natural and anthropogenic
both).
2. Waste disposal at personal level should be optimally reduced as waste destruction
by any means causes pollution.
3. Maintenance of vehicles should remain proper as to avoid introduction of harmful
gases and other pollutants in to the atmosphere.
4. Generators and other household gadgets that add to pollution of environment should
be kept well maintained.
5. Use of chemical fertilizers should be limited as to avoid water pollution e.g. DDT
6. Timely disposal of waste to prevent decomposition of household refuge as to check
foul odours and spread of disease by insects, flies and other pathogenic bacteria.
7. Industrialists should check for proper disposal of treated water from factory units
as to avoid thermal pollution of water bodies. They should also deploy a water
treatment plant to prevent the flow of hazardous material.
8. Service centres of vehicles should minimize the disposal of organic solvents into the
main drains.
9. Music lovers should listen and operate their music systems at optimum levels as
to avoid noise pollution
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1. Constant noise affects a man physically and mentally. Physical effects include
blood vessels to contract, skin to become pale, muscles to constrict and rise in blood
pressure leading to tension and nervousness.
2. High intensity sound emitted by industrial plants, bottling machines, supersonic
aircrafts, when continued for long periods of time not only disturbs but also
permanently damages hearing.
3. Offices, industries and crowded places where constant noise prevails can produce
temper tantrums, headaches, fatigue and nausea.
4. Loud and sudden noise affect the brain. Intermittent noise leads higher incidence
of psychiatric illness and also a danger to health of pregnant mothers and small
infants.
5. Noise has harmful effects on nonliving materials too, e.g. cracks develop under the
stress of explosive sound.
Control of Noise Pollution
Following methods can control noise pollution:
1. Limited use of loudspeakers and amplifiers.
2. Excursing control over noise producing vehicles.
3. Industrial workers should be provided with ear plugs.
4. Delocalisation of noisy industries far away from dwelling units.
5. Within a radius of 10 miles of airport, no buildings or factories should be allowed.
6. Plants and trees should be planted all around the hospitals, libraries and schools
and colleges.
7. Personal protection against noise can be taken by using, cotton plugs in the ear.
Radiation
The radiations from the atomic blasts cause several health hazards. The radiations
carry high energy and remove electrons from atoms and attach them to other atoms producing
positive and negative ion pairs. Hence, they are known as ionizing radiations. The ionization
property of these radiations proves to be highly injurious to the protoplasm. The ionizing
radiations of ecological concern are classified as follows:
Corpuscular Radiations
These consist of streams of atomic or subatomic particles, which transfer their energy
to the matter they strike.
(i) Alpha particles
These particles are large and travel few centimeters in the air. These cause large
amount of local ionization.
(ii) Beta particles
These are small particles characterized by having high velocities. They can travel a few
meters in space. These are capable of entering into the tissues for few centimeters.
Since alpha and beta particles have low penetration power they can produce harmful
effects only when absorbed, ingested or deposited in or near living tissues.
(iii) Electromagnetic radiations
Electromagnetic radiations include waves of shorter wavelengths. These are capable of
traveling long distances and can readily penetrate the living tissue. These include gamma
rays. These can penetrate and produce effect even without being taken inside.
Other Types of Radiations
Besides radioactive radiations, some other radiations are also present in the atmosphere
(i) Neutrons
These are large uncharged particles, which do not cause radiation by themselves, but
they produce radioactivity in non-radioactive materials through which they pass.
(ii) X-rays
These are electromagnetic waves very similar to gamma rays, but originate from the
outer electron shell of radioactive substances, which are not dispersed in nature.
(iii) Cosmic rays
These are radiations from the outer space, which contain alpha and beta particles
together with gamma rays.
Sources of Radiations
The radiations are produced from the radioactive elements, which are known as
radionuclides or radioactive isotopes, e.g. Uranium. Radium, Thorium, and Carbon-14. These
contribute to background radiation. But isotopes of certain metabolically important elements
like Carbon-14, Cobalt-60, Calcium 45, Iodine-131, Phosphorus-32, etc. are not ecologically
harmful but are used as tracers. The third category of radionuclides comprises of fission
products of uranium and certain other elements. These are cesium, strontium, and plutonium
etc.
Biological Effects of Radiation
The effects of radiation have revealed that acute doses are found to be deleterious and
may kill the organisms, whereas the increase in radiation in biological environment leads
to different kinds of mutations. The effects of Cobalt-60 or Cesium-137 gamma radiations
have now been studied on communities and on ecosystems at different places. The research
concludes that Irradiations eliminate varieties in species. The sensitivity of cells, tissues and
organisms to radiation varies. The cells with larger chromosomes are more sensitive.
Herbaceous communities and early stages of succession are resistant than the mature forest.
Nuclear Fall Outs or Radioactive Fall Outs
The atomic blasts not only produce the local ionizing radiations at that time but the
radioisotopes produced as a result of explosion enter the atmosphere and continue to fallout
gradually over broad geographic areas for a very long time. These are known as nuclear
fallout or radioactive fallout. These are dangerous for life as they also produce ionizing
radiations.
Biological Effects of Fall outs
The fallout of radionuclides combines with various metals and dust and from colloidal
suspension combines with organic compounds to form complexes. The smaller particles of
radionuclides adhere tightly to the leaves of plants and produce radiation damage to leaf
tissue besides entering the tissues also. Through grazing animals these enter the food chain
directly at the primary consumers level. Radionuclides, which combine with organic
substances, enter the food chain through producer tropic level. Therefore, the radionuclides
fall out manages to enter the body of all living organisms. Radioactive Strontium-90 poses
a health hazard in human beings and other higher vertebrates. It continues to deposit in
the bones and causes bone cancer and leukemia. Radioactive Cesium-137 is known to cause
irreversible genetic changes in different organisms. The fallout radiations do cause changes
in the genetic constitution of organisms, resulting in gene mutations and chromosomal
aberrations. Their considerable, doses may kill, cripple and alter the animals and plants in
the areas.
Control of Radiation Pollution
Following measures can help in controlling the radioactive pollution:
(i) Workers in nuclear plants should be provided with nuclear gadgets and safety
measures against accidents.
(ii) Leakage of radioactive elements from nuclear reactors, laboratories, transport,
careless handling and use of radioactive fuels should be checked.
(iii) Level of radiation pollution should be monitored regularly in risk areas.
(iv) Disposal of radioactive wastes deserves special attention.
Case studies
Hiroshima and Nagasaki Episode
The tale of Hiroshima and Nagasaki is a painful experience. It is for the first time that
an atomic bomb has been exploded over human population. The incident took place on
August 6,1945 at 8:15 a.m. The bomb with an approximate temperature of around 100
million 0°C was exploded on a fine morning in Hiroshima (Japan). The temperature of the
city hiked like anything, almost like an oven. After three days, Nagasaki too suffered the
ravages of a nuclear attack. More than 1,00,000 people were reported to die just after the
event took place. Since radiations from nuclear elements remain active even after, the
generations to follow up also suffered from various diseases. Even the babies in the mother’s
womb were affected and a few perished. Blindness, deafness, skin diseases and cancers,
distortion of bones and other parts became the fortune of human civilization.
Chernobyl Accident
This incident took place in Ukraine on April 26, 1986. There was a Chernobyl nuclear
power plant in Ukraine after which the event has been named. Approximately four million
people had been reported to suffer from the accident. The accident contaminated neighboring
environment up to several kilometers. The sites were evacuated and resettlement was done
for the affected people. The radiations released affected ground water and surface waters,
affecting large areas of Europe. 131 Iodine and 137 Cesium are the most dangerous amongst
the 20-odd radioactive elements released during Chernobyl disaster. As per the Soviet Health
Ministry, 31-persons died shortly after the disaster. Of the 276,614 people who worked for
rehabilitation and cleaning operations, a total of 1065 died by the end of 1990.
Marine Pollution
All river drainages end up in the seas. On the way to sea, rivers carry large amounts
of sewage, garbage, and agricultural discharge, biocides, including heavy metals. Besides
this discharge of oils and petroleum products and dumping of radionuclides waste into sea
also cause marine pollution. Huge quantity of plastic is being added to sea and oceans. Over
50 million lb plastic packing material is being dumped in sea of commercial fleets. Many
marine birds ingest plastic that causes gastro-intestinal disorders. The chemical principle in
PCBs causes more damage as thinning of eggshell and tissue damage of egg. Radionuclide
waste in sea includes Sr-90, Cs-137, Pu-239, and And Pu-240.
The pollutants in sea may become dispersed by turbulence and ocean currents and
finally becomes a part of food chain. Bioaccumulation in food chain may result into loss of
species diversity. The pollution in Baltic sea along the coast of Finland, took place largely
from sewage and effluents from wood industries. This pollution effect brought changes. in
species diversity in the bottom fauna. In less polluted water there was rich species diversity,
which tended to decrease with increasing pollution load. In heavily polluted areas, macroscopic
benthic animals were absent, but chirognomy larvae occurred at the bottom. In marine
water the most serious pollutant is oil. Spill of oil or petroleum products due to accidents/
deliberate discharge of oil polluted waste brings about pollution. About 285 million gallons
of oil are spilled each year into ocean, mostly from transport tankers. Oil pollution causes
damage to marine fauna and flora including algae, fish, birds, and invertebrates. About
50,000 to 2,50,000 birds are killed every year by oil. The oil is soaked in feathers, displacing
the air and thus interferes with buoyancy and maintenance of body temperature.
Hydrocarbons and benzpyrene accumulate in food chain and consumption of fish by man
may cause cancer. Detergents used to clean up the spill are also harmful to marine life.
Thermal Pollution
The increase in water temperature by industrial units such as steel and iron factories,
electric powerhouses and atomic power plants may be called as thermal pollution. Some of
the industries generate their own power supply where water is used to cool the generators.
This hot water is released into the main stream, causing a warming trend of surface waters.
If the drainage is poorly flushed, a permanent increase in the temperature may result.
Many organisms are killed instantly by the hot water resulting into a high mortality.
It may bring other disturbance in the ecosystem. The eggs of fish may hatch early or fail
to hatch at all. It may change the diurnal and seasonal behaviour and metabolic responses
of organisms” It may lead to unplanned migration of aquatic animals. Macrophysics population
may also be changed. As temperature is an important limiting factor, serious changes may
be brought about even by a slight increase in temperature in a population. Heat stress
(5-1 one above the normal growing temperature of organism) induces expression of specific
gene families called heat shock genes, which lead to the synthesis of a new set of proteins
called heat shock proteins. Heat shock proteins have been found in every organism from
unicellular prokaryotes to multicultural organisms including Homo sapiens. Heat Shock
Proteins synthesis lead to acquired thermo tolerance, i.e. the ability of an organism to
withstand a normally lethal temperature. Thermo tolerant genotypes show adaptations at
various levels of organization besides showing qualitative and quantitative differences in
heat shock proteins as compared to the thermo sensitive genotypes.
Solid Waste Management
Environmental problems also include solid waste disposal. At all levels of development
human beings produce domestic wastes. These comprises of kitchen wastes, ashes from
fires, broken utensils and worn-out clothing. The industrial revolution leads to the
concentration of people in urban areas with very high population density. This resulted in
addition of new sources of wastes from shops, institutions and factories. In developed countries
services for the regular removal of domestic and trade wastes have been in operation for last
many years.
Many changes have taken place in our society. The character of the wastes has altered
with rising living standards, changes in retail distribution methods and fuel technology.
Grave environmental concerns have come up with rise in construction of new buildings,
supermarkets, and industrial wastes of many kinds. In the industrialized countries, therefore,
basic health and environmental problems have been solved in the storage and collection of
solid wastes, although major problems remain in regard to resource recovery and disposal.
The technology of wastes handling is now highly developed. The substantial sectors of
industry are engaged in the production of equipment with regard to removal of wastes.
Many institutions give technical training and support. However developing nations like
India are facing the problems of urbanization with high population densities. The developing
countries are aware of the importance of avoiding the environmental pollution. The quality
of urban environment is a matter of growing concern and the importance of solid wastes
management is increasingly being recognized
Sources and Characteristics
Solid wastes generally refer to describe non-liquid waste materials arising from domestic,
trade, commercial, industrial, agriculture and mining activities and from the public services.
Disposal of sludge’s (liquid waste) of some kind fall within the scope of solid waste
management. These arise primarily from industrial sources and from sewage treatment
plants. Solid wastes comprise countless different materials; dust, food wastes, packaging in
the form of paper, metals, plastics or glass, discarded clothing and furnishing, garden wastes
and hazardous and radioactive wastes. The method and capacity of storage, the correct type
of collection vehicle, the optimum size of crew and the frequency of collection depend mainly
on volume and density. Just as solid wastes comprise a vast number of materials, they arise
from a multitude of separate sources as well as many kilometers of streets upon which solid
wastes accumulate. Thus, the four main aspects of solid wastes management are: (i) storage
at or near the point of generation, (ii) collection, (iii) street cleansing, (iv) disposal.
The main constituents of solid wastes are similar throughout the world, but the
proportions vary widely. As personal income rises, paper increases, kitchen wastes decline,
metals and glass increase, total weight generated rises and the density of the wastes declines.
Clearly, the amount of work involved in refuse collection depends upon the weight and
volume of wastes generated and the number of collection points from which the wastes have
to be removed.
Health and environmental implications
Improper handling of solid wastes results in increased potential risks to health and to
the environment both. Direct health risks concern mainly the workers in this field, who
need to be protected, as far as possible, from skin contact with wastes. For the general
public, the main risks to health are indirect and arise from the breeding of disease vectors,
primarily flies and rats. More serious, however, and often unrecognized, is the transfer of
pollution to water, which occurs when the leach ate from a refuse dump enters surface water
or wastes, either in the open air, or in plants that lack effective treatment facilities for the
gaseous effluents. Traffic accidents can result from wastes accumulated and dispersed on to
streets and roads. They have caused death and injury to people in the surrounding areas.
There also persists the specific danger of the concentration of heavy metals in the food
chain. These metals can be taken up by the plants growing on land on which sludge has
been deposited, creating risks to the animals which graze and the humans who consume
these animals.
Economic implications
Labour and transport absorb the major part of the operating cost of solid wastes
management services. The level of mechanization that should be adopted for solid wastes
management systems relates directly to the cost of labour, as compared to that of plant and
energy. There is not much variation, worldwide, in energy or mechanical plant costs, but
there is wide variation in the range of labour costs. Thus, there are no universally applicable
solid wastes management systems. Every country must evolve indigenous technology based
on the quantity and character of the wastes, the level of national wealth, wage rates,
equipment, manufacturing capacity, energy costs etc. It is necessary to deploy a complete
set of technical skills, which derive from several professional disciplines. These include civil
and mechanical engineering, chemical engineering, transport organization, land use planning
and economics.
Refuse Collection
A refuse collection service requires vehicles and labour. For their efficient development,
three components are basic:
(1) Travel to and from the work area,
(2) The collection process, and
(3) The delivery process.
The use of large, widely spaced communal storage sites is usually a failure because the
demand placed on the householder goes beyond his willingness to cooperate. Communal
storage points should, therefore, be at frequent intervals, Madras and Bangalore provide
fixed concrete containers. They are fairly successful because they place reasonable and
acceptable duty on the residents, thus very little domestic waste is thrown in the street.
In another system of block collection, a collection vehicle travels a regular route at
prescribed intervals, usually every two days or every three days, and it stops at every street
intersection, where a bell is rung. At this signal the residents of all the streets leading from
that intersection bring their wastes containers to the vehicle and hand them to the crew to
be emptied. A crew of one or two men is adequate in number, as they do not need to leave
the vehicle.
Sanitary Landfill Disposal
Land disposal (burying of wastes) is the only approved method of disposal, which is
performed at a single site. Incineration, composting, and salvage are either a form of refuse
handling or processing. They are not complete methods of disposal, and they require disposal
of residue. Sanitary landfill can be defined as the use of solid wastes for land-reclamation,
a typical example being the restoration, by filling to the original level of man made surface
dereliction such as a disused surface, mineral excavation. Solid wastes may also be used to
improve natural features by raising the level of low-lying land to enable it to be used or
cultivation or industrial development. Thus, sanitary land filling has two essential features,
which differentiate it from crude dumping:
(i) Only sites that will be improved not degraded, by a change of level are selected.
(ii) Simple engineering techniques are used to control the manner in which the wastes
are deposited, so that dangers to public health and the environment are avoided.
Unfortunately most of the world’s wastes are disposed off by uncontrolled dumping
which blights the land for any future use and causes serious risks of water pollution and
vector breeding. Very few cities operate sanitary land filling to standards, which totally
control health and environmental dangers; most of those that do are in the industrialized
countries.
Control of Hazards
(i) Control over pathogens is dependent upon a rigorous policy of covering the wastes
soon after deposit. This serves both to isolate the wastes and to retain the heat,
which is quickly generated during aerobic decomposition.
(ii) The main source of insects will be the eggs of flies. Which have been deposited in
the wastes before they arrive at the site. Most of these will be buried deep in the
wastes and will succumb to the temperature increase.
(iii) Fire at a sanitary landfill can arise from innumerable causes, hot ashes in a vehicle
delivering wastes: a cigarette thrown by a worker; the sun’s ray though a fragment
of glass on the surface. With some kinds of wastes the consequence of fire may be
very serious and underground fires have been known that ultimately caused the
collapse of the surface into voids caused by the fire.
(iv) The pollution of static water, ditches, river or the sea occurs when a sanitary
landfill adjoins a body of water. The normal source of the leach ate causing this
pollution is rain falling on the surface.
Incineration
Open burning, barrel burning, and other related uncontrolled forms of burning have a
long history of use. Many liquid wastes and pathological wastes are best disposed of by
incineration. Originally, solid waste incineration was practiced to reduce the quantity of
refuse or disposal. After it was proven that heat could destroy most pathogens, incinerators
were used in hospitals for destruction of pathological wastes. With few exceptions, incinerators
are not “good neighbors,” and the environmental nuisances of dust. Noise and air pollution
have provoked communities to an anti-incinerator philosophy. To overcome this negative
community feeling is going to require that incineration prove its worth and that imagination
be used in the design of future units. Incineration of solid wastes yields the highest percent
of volume reduction except for Pyrolysis. Unlike a sanitary landfill, incineration of solid
wastes can be performed on the premises of apartments, supermarkets, departments’ stores,
and similar establishments.
Composting
Composting involves the biological stabilization of solid matter either under aerobic or
anaerobic conditions. The end product of composing is an organic material, which could have
beneficial value as a soil conditioner or plant mulch. In addition to producing a modified
solid waste material, which can be useful in land reclamation, composting does yield a
volume reduction of solid waste by about 40-60% of the compost able fraction pyrolysis
Pyrolysis is a thermal process where oxidation of the organic fraction is not allowed to
occur. Instead, the organic matter is evolved from the refuse with heat, leaving an ash
consisting mostly of carbon and any inorganic matter, e.g. metal and glass are not removed
before Pyrolysis. Some of the gases, which have been volatized, are condensed while the
remainder is burned to supply the heat (energy) needed to pyrolyze the material. Since
oxidation is prevented, the Pyrolysis process must be performed in an atmosphere of argon,
helium or nitrogen.
Role of an Individual in Prevention of Pollution
Which are the most viable, efficient and economical ways to eliminate pollution problems?
We very often see people blaming public and government sectors to control pollution through
controlling market mechanisms and government blaming people to avoid and check pollution.
Who would control whom? Many ecologists and environmental scientists believe in that
pollution problems can be overcome by using market mechanisms to reduce pollution rather
than rigid rules and regulations. However, on the other hand man should identify and gear
up his own potential to curb down pollution. Man could achieve this by identifying his own
role at individual level in prevention of pollution. This is possible through environmental
awareness, education and enlightenment.
Ways and means by which pollution problems can be greatly reduced at individual level
are:
1. Masses at personal level should determine to consume optimum level of resources,
which would lead a comfortable life. Because excessive resource consumption is in
someway related to pollution problems and hazards (natural and anthropogenic
both).
2. Waste disposal at personal level should be optimally reduced as waste destruction
by any means causes pollution.
3. Maintenance of vehicles should remain proper as to avoid introduction of harmful
gases and other pollutants in to the atmosphere.
4. Generators and other household gadgets that add to pollution of environment should
be kept well maintained.
5. Use of chemical fertilizers should be limited as to avoid water pollution e.g. DDT
6. Timely disposal of waste to prevent decomposition of household refuge as to check
foul odours and spread of disease by insects, flies and other pathogenic bacteria.
7. Industrialists should check for proper disposal of treated water from factory units
as to avoid thermal pollution of water bodies. They should also deploy a water
treatment plant to prevent the flow of hazardous material.
8. Service centres of vehicles should minimize the disposal of organic solvents into the
main drains.
9. Music lovers should listen and operate their music systems at optimum levels as
to avoid noise pollution
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