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AIR POLLUTION
Project Guide: Dr. Tanuja Nautiyal
Presentation by:Subrat, Vishal, Ashley
WHAT IS POLLUTION?
Pollution is introduction of contamination into natural environment that cause adverse change. Pollutants are the substances causing pollution.
WHAT ARE DIFFERENT TYPES OF POLLUTION?
TYPES OF POLLUTION
AIR POLLUTION
RADIOACTIVE CONTAMINATION
SOIL CONTAMINATION
LIGHT POLLUTION
WATER POLLUTION
LITTERING
NOISE POLLUTION
THERMAL POLLUTION
WHAT IS AIR POLLUTION?
Air pollution is introduction of particles, biological molecules, or other harmful materials into earth's atmosphere, causing death to humans, disease, damage to other living organism such as food crops or natural or built environment.
WHAT ARE THE SOURCES OF AIR POLLUTION?
Sources of air pollution may be natural or man made.
Natural sources Volcanic eruption emitting
poisonous gases like H2S, SO2.
Decay of vegetation. Marsh gases pollen grains forest fires.
Manmade sources Increase in pollution. Deforestation. Industrialization. Explosives in wars. Vehicular emissions. Use of pesticides,
insecticides in agriculture.
WHAT ARE THE DIFFERENT TYPES OF AIR POLLUTANTS?
ON BASIS OF ORIGIN
ON BASIS OF PHYSICAL STATE
PRIMARY POLLUTANTS
SECONDARY POLLUTANTS PARTICULATE
GASEOUS
WHAT ARE THE EFFECTS OF AIR POLLUTION?
PARTICULATE MATTERACID RAIN
GREEN HOUSE EFFECT
EUTROPHICATION
OZONE LAYER & ITS DEPLETION
ACID RAINChemical reactions involving air pollutants can create acid compounds which can create acidic compounds which can cause harm to vegetation and buildings. Sometimes, when an air pollutant such as sulphuric acid combines with water droplets that makes up clouds, water droplets become acidic, forming acid rain. When acid rain falls over an area, it can kill trees and harm animals, fish and other wildlife. Acid rain destroys leaves of plants. When acid rain infiltrates into soils, it changes chemistry of soil making it unfit for many living things that rely on soil as a habitat or for nutrition. Acid rain also changes the chemistry of lakes and streams that rain water flows into, harming fish and other aquatic life. The buildings and materials made of marble, limestone etc. suffer extensive damage due to acid rains.Reaction: CaCO3 + H2SO4 --------> CaSO4 + CO2 +H2OPaints on car can react with acid rain causing fading.
GREENHOUSE EFFECTGreenhouse effect is rise in temperature that earth experiences because certain gases in atmosphere absorb energy from the sun. Without these gases, heat would escape back into space and earth average temperature would be about 60° colder.
EVERYDAY EXAMPLE OF GREEN HOUSE EFFECTIf you open the door of a car that has been parked in sun for couple of hours, you will notice that temperature inside the car is much warmer than temperature outside. This is an example of greenhouse effect.Green house effect is due to presence of green house gases: Carbon dioxide Methane Nitrous oxide Chlorofluoro Carbon
OZONE LAYER AND
ITS DEPLETIONMost ozone resides in upper part of the atmosphere called stratosphere extending from 16KM to 40KM. About 90% of ozone is in troposphere. The light concentration of ozone in stratosphere shields us from ultraviolet light from sun and hence is referred as earths protective umbrella. Ozone is formed in atmosphere in multistep chemical processes that require sunlight.
O2 + hv -------> O + O -----------(1)O + O2 + M -------> O3 + M -----------(2)O3 + hv -------> O2 + O -----------(3)
Effects of ozone depletion: UV radiations can cause sunburn, skin cancer, various damage to
plants and animals. Exposure to UV radiation damages cornea and lens causing
blindness. A 5% depletion in ozone produces 10%increase in radiations
reaching earth according to an estimate i.e. it would produce 5 times additional skin cancer per year worldwide.
The DNA has capacity to absorb UV radiations which may cause various descriptive effects.
Ozone depletion has a strong effect on climate.
CFCs has been banned worldwide and HCFC (Hydro-chloro-fluoro Carbons ) are substituted for CFCs in air conditioners and refrigerators.
EUTROPHICATIONRain can carry and deposit nitrogen in some pollutants on rivers and soils. This will adversely affect nutrients in soil and water bodies. This can result in algae growth in lakes and water bodies, and make conditions for other living organisms harmful.
PARTICUALTE MATTERAir pollutants can be in form of particulate matter which can be very harmful to our health. Short term effects include irritation to eyes, nose and throat and upper respiratory infections such as bronchitis and pneumonia. Others include headaches, nausea and allergic reactions . Long term health effects are chronic respiratory disease, lung cancer, heart disease and even damage to brain, nerves, liver or kidneys. Continual exposure to air pollution affects lungs of growing children and may aggravate or complicate medical condition in elderly.
HOW TO PREVENT POLLUTION?Government (Or Community) Level Prevention Governments throughout the world have already taken action by
introducing green energy. Some are investing in wind, solar energy as well as other renewable energy, to minimize burning of fossil fuels, which cause heavy air pollution.
Government are also forcing companies to be more responsible with their manufacturing activities, so though they cause pollution, they are a lot controlled.
Car manufacturing companies are also building more energy efficient cars, which pollute less than before.
Individual Level Prevention Encourage your family to use bus, train or bike when commuting. If we all
do this, there will be less cars on road and less fumes. Use energy wisely. This is because lots of fossil fuels are burned to generate
electricity and so if we cut down the use, we will also cut down the amount of pollution we create.
Recycle and reuse things. Remember manufacturing industries create a lot of things, thus reusing thing can be of great help.
BHOPAL GAS TRAGEDY
In the early morning hours of December 3,1984, a poisonous grey cloud (40 tones of toxic gases) from Union Carbide India Limited Pesticide Plant at Bhopal spread throughout the city. Water carrying catalytic material had entered Methyl isocyanate (MIC) storage tank no. 610. The killer gas entered the city and spread throughout sending residents scurrying through dark streets. Estimates suggested that as many as 10,000 may have died immediately and 30,000 to 50,000 were too ill to ever return to their jobs. The catastrophe raised some serious ethical issues. The pesticide factory was built in midst of densely populated settlements. UCIL chose to store and produce MIC, one of the most deadly chemicals in an area where nearly 12,000 people lived. MIC in the tank was filled to 87% of its capacity while the maximum permissible was 50% MIC was not stored at zero degree centigrade as prescribed and refrigeration and cooling systems had been shut down five months before disaster. Vital gauges and indicators in MIC tank were defective. The flare tower meant to burn off MIC emission was under repair at the time of disaster and scrubber contained no caustic soda. The work force in
factory was brought down to half from 1980 to 1984. This had serious consequences on safety and maintenance. There was no maintenance supervisor. This incident had long term effects: Eyes (Scars on cornea, early cataracts, corneal opacities) Respiratory tracts (pulmonary fibrosis, chronic bronchitis) Neurological system (numbness, finer motor skills, impairment of
memory) Psychological problems (Post traumatic stress disorder) Children’s health
Factory was closed in 1986.
DISCOLOURATION OF TAJ MAHALOver the past 2 decades, India's most famous tourist attraction. Taj Mahal located in Agra has become a matter of concern. Experts have warned that pollutants in air are discoloring its white marble. So it is not only living organisms that get affected by polluted air but non living things like buildings, monuments and statues also get affected. The industries located in and around Agra like rubber processing, automobiles, chemicals and especially the Mathura oil refinery have been responsible for producing pollutants like sulphur dioxide and nitrogen dioxide. These gases react with water vapour present in atmosphere to form sulphuric and nitric acid. This acid drops down with rain causing acid rain. Acid rain corrodes the marble of the monument. Supreme court has taken several steps to save Taj. It has ordered industries to switch to cleaner fuels like CNG and LPG. moreover the automobiles should switch over to unleaded petrol near Taj zone. The Archaeological Survey of India said that it might have to do mud pack therapy on Taj Mahal yearly, when it was only previously done once every 5 to 6 years.
THANK YOU