Environmental Pollution Definition- Causes, effects and control measures of:- a. Air pollution b. Water pollution c. Soil pollution d. marine pollution e. Noise pollution f. Thermal pollution
g. Nuclear hazards. Solid waste management: Causes, effect and control measures of urban and industrial wastes; Role of an individual in prevention of pollution; Pollution case studies; Disaster management: floods, earthquake, cyclone and land slides.( 04 Lectures)
What is a pollutant?
A pollutant is one which is harmful to the environment.
What are the various effects of pollution?
The effect of pollution is undesirable change in ecology which results in harmful effect on human beings, animals & plants.
Who contributes most to pollution?
Human beings
How much air do you think a human being needs per day?
Approximately 12 Kgs!
How can we classify pollutants?
Pollutants can be classified into (i) Degradable (ii) Slowly-degradable pollutants & (iii) Non-degradable
Can you give examples for (i) Degradable (ii) Slowly-degradable &(iii) Non-degradable pollutants?
(i) Degradable - Domestic sewage, Discarded vegetables etc.
(ii) Slowly-degradable pollutants – Plastics, DDT(Pesticide)
5.1 Air Pollution - Some History.
Can you guess who might have first expressed concern over air pollution?
Hippocrates in 400B.C
When was the first anti-pollution law passed?
King Edward-I passed the first anti-pollution law in the year 1273 which prevented people from using coal for domestic heating.
Which was the earliest recorded major disaster in the history?
“London Smog” in 1952 that resulted in 4000 deaths.
When was the first anti-pollution law passed in
The Air Pollution Control Act in
Can you list some of the major disasters leading to serious air pollution?
(i) “London Smog” in 1952 that resulted in 4000 deaths.
(ii) Leakage of Methyl iso-cyanide gas from Union carbide’s pesticide plant in 1984 which affected thousands of people in
What are the components of atmosphere?
Atmosphere consists of 79% Nitrogen, 20% Oxygen,1% as mixture of Carbondioxide, water vapour and trace amounts of several other gases such as neon, helium, methane, krypton, hydrogen and xenon.
Can you list the various layers of atmosphere?
The inner most layer - Troposphere
The next layer – Stratosphere
Further next layer – Mesosphere.
Do you know the layer in which airplanes fly?
Stratosphere
Do you know the layer in which Ozone is available?
Stratosphere
What is the significance of Ozone layer?
The ozone layer effectively screens the UV light.
Why the Ozone layer is given so much importance?
The Ozone layer as such consists of not only ozone but a mixture of other gas molecules. In the densest ozone layer there is only one ozone molecule in one lakh gas molecules.(1/100000).Therefore even a small change in ozone concentration can produce dramatic effects on the life on earth.
How is the presence of ozone expressed/measured technically?
The total amount of ozone in a ‘Column’ of air from the earths surface up to an altitude of 50Kms is the Total column ozone and is recorded in Dobson Units(DU), a measure of thickness of ozone layer by an equivalent layer of pure ozone gas at normal temperature and pressure at sea level. This means that 100DU = 1 mm of pure ozone gas at normal temperature and pressure at sea level.
What a pollutant does to ozone layer?
Pollutants accelerate the breakdown of ozone which may lead to large scale destruction of ozone also called ‘Ozone Hole’.
Can you name some pollutants that are harmful to Ozone layer?
CFCs, Halons etc – these are known as ozone depleting substances.
What are the adverse effects of ozone depletion?
Increased exposure to UV radiation may result in Sunburn, cataract, aging of skin and skin cancer. Food production will get affected. Marine food chain will get affected.
Air Pollution scenario in
Which Indian cities are found to emit more pollutants?
Ahmedabad’s air is found to be the most noxious, followed by
Water Pollution:
Can you guess the quantity of water that is available as fresh water for potable purpose?
Although 71% of the earth’s surface is covered by water, only a tiny fraction of this water is available to us as fresh water. About 97% of the total water is found in the oceans and remaining 3% is fresh water. Of this 2.997% is locked in ice caps or glaciers. Thus only 0.003% of the earth’s total volume is available as fresh water.
How do you decide water is polluted?
When the quality of water or composition of water changes directly or indirectly which makes water unfit for any purpose.
Soil Pollution:
Which place in
Severe cases of arsenic poisoning from contaminated ground water have been reported from west
Do you know the classification of soil in terms of horizon terminology?
Top layer of soil is called A-Horizon.
The sub soil called B-Horizon & the area below sub soil known as C-Horizon.
What is the major drawback of pesticides that we use?
Persistent pesticides once applied are effective for a long time. However they do not breakdown easily and tend to accumulate in the soil and in the bodies of animals in the food chain.
What are the meaning of the terms ‘Bioaccumulation’ & ‘Biomagnification’?
Persistent pesticides once applied are effective for a long time. However they do not breakdown easily and tend to accumulate in the soil and in the bodies of animals in the food chain. If the animal is unable to flush them out of its system it may lead to bioaccumulation. When an affected animal is eaten by another carnivore, these pesticides are further concentrated in the body of the carnivore. This Phenomenon of acquiring increased levels of a substance in the bodies of higher tropic level organisms is known as ‘Bio magnification’.
What is the role of IPM in reducing the impact of pesticides?
Integrated Pest Management (IPM) is a technique that studies ecological aspects of a crop and suggests control strategies that uses no or few peticides. IPM also promotes the use of Biopesticides.
Marine Pollution:
What do you think are the various source of marine water pollution?
- Waste water that is directly discharged into the sea.
- Chemicals, fertilizers and pesticides that are washed off the land by rain
- Petroleum and oil washed off the roads enter sea during storm water overflows.
- Ship accidents and resulting slippage of oil
- Offshore oil exploration
How do you control marine water pollution with the help of sewage treatment plants?
Sewage treatment plants can reduce BOD (Biological Oxygen Demand) of the final product before it is discharged into the sea and thereby help in controlling pollution.
What are the various stages of treatment in sewage treatment plants?
Primary treatment- Screening, Sedimentation.
Secondary treatment – Trickling filters
Can you name some of the common sources which are responsible for sea pollution?
Tanker operations
Dry Docking
Bilge and fuel oils
Tanker accidents
Offshore oil production.
Can we control oil polluting the sea?
Yes. Use of chemical dispersants can accelerate the process of natural emulsification of oil. A variety of slick-lickers are available in the market. High pressure steam can be used in cleaning the walls.
Noise Pollution:
Do you think noise pollution is a serious problem?
Yes. The sound levels beyond specific limits can harm the eardrum and person may loose his hearing ability. Noise can also cause emotional and psychological effects such as irritability, anxiety and stress.
Can you name some common sources of noise pollution?
Construction activities, drilling activities, traffic horns, Fire crackers & Drums etc.
How to control noise pollution?
- Reduce the noise at source.
- Block the path of noise.
- Increase the path length.
- Protect the recipient.
Thermal Pollution:
What is the main source of thermal pollution?
Industries that throw heated water directly into the river without treating or cooling it.
Can you guess the temperature difference of heated water?
The heated water is at least 150 C higher than the normal water temperature.
Nuclear Pollution:
Do you think nuclear pollution is a serious threat like water or land pollution?
The degree and kind of damage from nuclear accidents vary with the kind of radiation. Therefore I would say nuclear pollution can cause very serious damage if not handled carefully & hence is a great threat to environment.
Have you ever heard of any nuclear accident?
On 25th apri’1986, in Ukraine improper handling of reactor resulted in an explosion which blew the 1000 metric tones of concrete roof from the reactor and the reactor caught fire.1,16,000 people were evacuated and 26,000 of them received serious doses of radiation.
Descriptive Questions:
- What is air pollution?
- Discuss briefly about types of particulates with examples.
- Explain control measures for air pollution.
- Explain the cause of water pollution and the control mechanisms to prevent the same.
- List factors that pollute the land and explain control mechanisms to prevent the same.
- What are the activities that result in marine pollution?
- Do you know the significance of a treatment plant and what are the various stages of sewage treatment?
- Explain the control measures that are to be taken while disposing municipal solid waste.
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