Lec-5
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Pollutants Responsible agents of pollution is called pollutants.
Pollutants • Primary pollutants: Chemicals or substances emitted directly into the air are primary pollutants. • Secondary pollutants: If these pollutants react with other substances in the air and form a new compound they are called secondary pollutants
Pollution
Pollution is the release of environmental contaminants. The U.S., Russia, Mexico, China and Japan are the world leaders in air pollution emissions; However, Canada is the number two country on a per capita basis. The major forms of pollution include:
Types of pollution • air pollution, the release of chemicals and particulates into the atmosphere. Common examples include carbon monoxide, sulfur dioxide, chlorofluorocarbons (CFCs), and nitrogen oxides produced by industry and motor vehicles. Ozone and smog are created as nitrogen oxides and hydrocarbons react to sunlight. • water pollution via surface runoff and leaching to groundwater. • Soil contamination occurs when chemicals are released by spill or underground storage tank leakage. Among the most significant soil contaminants are hydrocarbons, heavy metals, MTBE, herbicides, pesticides and chlorinated hydrocarbons.
Types of pollution • radioactive contamination, added in the wake of 20thcentury discoveries in atomic physics. (See alpha emitters and actinides in the environment.) • noise pollution, which encompasses roadway noise, aircraft noise, industrial noise as well as high-intensity sonar. • light pollution, includes light trespass, over-illumination and astronomical interference. • visual pollution, which can refer to the presence of overhead power lines, motorway billboards, scarred landforms (as from strip mining), open storage of junk or municipal solid waste.
Air pollution The air pollution may be defined as qualitative and quantitative changes in the atmospheric constituents due to addition or contamination of such substances as may be harmful to man and his environment. Fresh air composition: N2 79% O2 20.94% CO2 0.032% Others 0.028%
Air pollution may be categorized in to indoor and out door pollutions • In door Pollution: Pollution of atmosphere inside building, offices and residences is called indoor air pollution. eg. CO2 from metabolic activities of living organisms, and combustion of fuels. • Out door pollution: Atmospheric pollution in the open space is referred to as outdoor air pollution. eg Lead from Automobiles and industrial emission, Ozone from photochemical reactions in atmosphere etc.
Causes of Air Pollution: Atmospheric pollution is increasing due to the following major factors: • Over population and increasing urbanization. • Increasing traffic • Industrialization and energy consumption
1. Over population and Urbanization: According to current estimates, the world population is increasing at an average by two per cent annually which means the addition of about one million people every five days or five people every couple of seconds. Increases in population would demand more food, water and land, the three items that are limited on the earth. This has resulted in disturbance in ecological balance, disruption of natural biogeochemical cycles and fast depletion of natural resources
Growing population created problems of employment. This leads people to move from villages to urban areas in search of employment, comfort and facilities. As a result, the cities are expanding in area and are being thickly populated. Thickly populated areas face a variety of problems such as congestion, large number of vehicles and its dust and smoke, accumulation of solid and liquid wastes, poor sanitation and management problems.
2. Increasing Traffic: Rapid increase in the number of automobiles in one of the potential factors responsible for air pollution in urban areas. The vehicles on road are mobile sources of air pollution. Combustion of fuel in aircraft engines produces hydrocarbons, nitrogen oxides, carbon monoxide, small amount of particulate matter, and sulphur oxides. Amounts of pollutants depend upon the fuel used, type of aircraft engine.
3. Industrial Growth and Energy Consumption:
Sources Industries, oil refineries, break field, stone crushing
These are the important sectors which are major sources for air pollution.
Causes: • Industries are producing a variety of toxic substances. • Break field, stone crushing sector and oil refineries are releasing tremendous amount of fly ash and many toxic gases in to the atmosphere. • Domestic burning, agricultural refuse, • firewood and dry dung burning are also contributing considerable amounts of pollutants to atmosphere.
• The United States alone discharges roughtly125 million tones of junk into the atmosphere each year and a conservative estimate for the whole world would be about 520 million tones every year.
Effects of air pollution Human beings breathe 14 kg of air into their lungs each day. Although some of the symptoms of pollution that people suffer involve the moist surfaces of the eyes, nose, and throat, the major site of impact is the lungs. Three categories of impact can be distinguished: a) Chronic: Pollution cause the gradual deterioration of a variety of physiological functions over a period of years. b) Acute: Pollutants bring on life-threatening reactions within a period of hours or days. c) Carcinogenic: Pollutants initiate changes within cells that lead to uncontrolled growth and division (cancer).
Some effects of air pollution: -Long term exposure to sulphur dioxide, SO2 can lead to bronchitis. - Chronic inhalation of ozone and particulates can cause inflammation and ultimately fibrosis of the lungs -Carbon monoxide (CO) reduces the capacity of the blood to carry oxygen, and extended low levels of carbon monoxide can contribute to heart disease. -Chronic exposure to nitrogen oxides (NO) is known to impair the immunesystem, leaving the lungs open to attack by bacteria and viruses (Pfafflin & Ziegler 1992, Miller 1997).
According to a results of a study in Switzerland the largest contribution to health cost relates to 2100 premature deaths in Switzerland due to exposure to fine particles (Wiederkehr 1998). -The most sensitive to air pollution are small children -Asthmatics, people with chronic pulmonary and heart disease, and the elderly. Asthma, an immune system disorder characterized by impaired breathing caused by constriction of air passageways, is usually brought on by contact with allergens.
Acid Rain an effect of air pollution When the pH of rain water or snow is less than 5.7 it is called Acid rain. Acid rain is man-made ecological event. It is mainly due to sulfuric acid and nitric acid.
Formation of acid rain: 1. Action of sulfur dioxide leading to acid rain: It is formed in two steps, • Conversion of sulfur dioxide in to sulfur trioxide by absorption of UV radiation • Reaction of secondary pollutant sulfur trioxide with moisture to form sulphuric acid. Sulphuric acid dissolved in rain drops falls on the earth surface as acid rains.
2. Action of nitrogen dioxide leading acid rain: Nitrogen dioxide acts to produce acid rain in two steps: • Formation of nitrogen dioxide and nitrogen peroxide by absorption of UV radiation from the sun. • Reaction of nitrogen dioxide and nitrogen peroxide with atmospheric moisture to form nitric acid which falls down as acid rain.
Effects of acid rain: • Acid rain causes irritation in the eyes and skin of human beings. • It may cause corrosion of many buildings, bridges and monuments, railings, fencings etc. • It affects on the enzymatic activities of living being. • Acid rains change the pH of soils and affect the plant growth in various ways. • It inhibits carbon dioxide fixation and photorespiration and adversely affects the productivity of crops.
Acid rain and a Monument The Taj Mahal of Agra is also facing danger from the acid rain because of oil refinery situated at Mathura very close to Agra. This refinery emits smoke and gaseous pollutants including sulfur dioxide. If the sulfur dioxide levels in air increases the resulting acidic precipitation may react with marbles and cause pitting in this wonderful monument that attracts people from all over the world.
Control of Air pollution
What can we DO ?
1. Automobiles must be either made to eliminate use of gasoline and diesel oil or complete combustion is obtained in the engine so that noxious compounds are not emitted. The automobiles, trucks and other transport systems must have an antismog device to minimize pollution. 2. Aforestation, Reforestation 3. Excessive and undesirable burning of vegetation should be stopped.
4. Smoking should be stopped (there is 5,00000 tones tobacco pollution annually). 5. Proper attention should be given by the government and general to make people realize the implications of environmental problem. 6. Legislation should be passed against pollution. 7. Environmental education is the best programme to deal with the environmental problems
Pollutants • Primary pollutants: Chemicals or substances emitted directly into the air are primary pollutants. • Secondary pollutants: If these pollutants react with other substances in the air and form a new compound they are called secondary pollutants
Pollution
Pollution is the release of environmental contaminants. The U.S., Russia, Mexico, China and Japan are the world leaders in air pollution emissions; However, Canada is the number two country on a per capita basis. The major forms of pollution include:
Types of pollution • air pollution, the release of chemicals and particulates into the atmosphere. Common examples include carbon monoxide, sulfur dioxide, chlorofluorocarbons (CFCs), and nitrogen oxides produced by industry and motor vehicles. Ozone and smog are created as nitrogen oxides and hydrocarbons react to sunlight. • water pollution via surface runoff and leaching to groundwater. • Soil contamination occurs when chemicals are released by spill or underground storage tank leakage. Among the most significant soil contaminants are hydrocarbons, heavy metals, MTBE, herbicides, pesticides and chlorinated hydrocarbons.
Types of pollution • radioactive contamination, added in the wake of 20thcentury discoveries in atomic physics. (See alpha emitters and actinides in the environment.) • noise pollution, which encompasses roadway noise, aircraft noise, industrial noise as well as high-intensity sonar. • light pollution, includes light trespass, over-illumination and astronomical interference. • visual pollution, which can refer to the presence of overhead power lines, motorway billboards, scarred landforms (as from strip mining), open storage of junk or municipal solid waste.
Air pollution The air pollution may be defined as qualitative and quantitative changes in the atmospheric constituents due to addition or contamination of such substances as may be harmful to man and his environment. Fresh air composition: N2 79% O2 20.94% CO2 0.032% Others 0.028%
Air pollution may be categorized in to indoor and out door pollutions • In door Pollution: Pollution of atmosphere inside building, offices and residences is called indoor air pollution. eg. CO2 from metabolic activities of living organisms, and combustion of fuels. • Out door pollution: Atmospheric pollution in the open space is referred to as outdoor air pollution. eg Lead from Automobiles and industrial emission, Ozone from photochemical reactions in atmosphere etc.
Causes of Air Pollution: Atmospheric pollution is increasing due to the following major factors: • Over population and increasing urbanization. • Increasing traffic • Industrialization and energy consumption
1. Over population and Urbanization: According to current estimates, the world population is increasing at an average by two per cent annually which means the addition of about one million people every five days or five people every couple of seconds. Increases in population would demand more food, water and land, the three items that are limited on the earth. This has resulted in disturbance in ecological balance, disruption of natural biogeochemical cycles and fast depletion of natural resources
Growing population created problems of employment. This leads people to move from villages to urban areas in search of employment, comfort and facilities. As a result, the cities are expanding in area and are being thickly populated. Thickly populated areas face a variety of problems such as congestion, large number of vehicles and its dust and smoke, accumulation of solid and liquid wastes, poor sanitation and management problems.
2. Increasing Traffic: Rapid increase in the number of automobiles in one of the potential factors responsible for air pollution in urban areas. The vehicles on road are mobile sources of air pollution. Combustion of fuel in aircraft engines produces hydrocarbons, nitrogen oxides, carbon monoxide, small amount of particulate matter, and sulphur oxides. Amounts of pollutants depend upon the fuel used, type of aircraft engine.
3. Industrial Growth and Energy Consumption:
Sources Industries, oil refineries, break field, stone crushing
These are the important sectors which are major sources for air pollution.
Causes: • Industries are producing a variety of toxic substances. • Break field, stone crushing sector and oil refineries are releasing tremendous amount of fly ash and many toxic gases in to the atmosphere. • Domestic burning, agricultural refuse, • firewood and dry dung burning are also contributing considerable amounts of pollutants to atmosphere.
• The United States alone discharges roughtly125 million tones of junk into the atmosphere each year and a conservative estimate for the whole world would be about 520 million tones every year.
Effects of air pollution Human beings breathe 14 kg of air into their lungs each day. Although some of the symptoms of pollution that people suffer involve the moist surfaces of the eyes, nose, and throat, the major site of impact is the lungs. Three categories of impact can be distinguished: a) Chronic: Pollution cause the gradual deterioration of a variety of physiological functions over a period of years. b) Acute: Pollutants bring on life-threatening reactions within a period of hours or days. c) Carcinogenic: Pollutants initiate changes within cells that lead to uncontrolled growth and division (cancer).
Some effects of air pollution: -Long term exposure to sulphur dioxide, SO2 can lead to bronchitis. - Chronic inhalation of ozone and particulates can cause inflammation and ultimately fibrosis of the lungs -Carbon monoxide (CO) reduces the capacity of the blood to carry oxygen, and extended low levels of carbon monoxide can contribute to heart disease. -Chronic exposure to nitrogen oxides (NO) is known to impair the immunesystem, leaving the lungs open to attack by bacteria and viruses (Pfafflin & Ziegler 1992, Miller 1997).
According to a results of a study in Switzerland the largest contribution to health cost relates to 2100 premature deaths in Switzerland due to exposure to fine particles (Wiederkehr 1998). -The most sensitive to air pollution are small children -Asthmatics, people with chronic pulmonary and heart disease, and the elderly. Asthma, an immune system disorder characterized by impaired breathing caused by constriction of air passageways, is usually brought on by contact with allergens.
Acid Rain an effect of air pollution When the pH of rain water or snow is less than 5.7 it is called Acid rain. Acid rain is man-made ecological event. It is mainly due to sulfuric acid and nitric acid.
Formation of acid rain: 1. Action of sulfur dioxide leading to acid rain: It is formed in two steps, • Conversion of sulfur dioxide in to sulfur trioxide by absorption of UV radiation • Reaction of secondary pollutant sulfur trioxide with moisture to form sulphuric acid. Sulphuric acid dissolved in rain drops falls on the earth surface as acid rains.
2. Action of nitrogen dioxide leading acid rain: Nitrogen dioxide acts to produce acid rain in two steps: • Formation of nitrogen dioxide and nitrogen peroxide by absorption of UV radiation from the sun. • Reaction of nitrogen dioxide and nitrogen peroxide with atmospheric moisture to form nitric acid which falls down as acid rain.
Effects of acid rain: • Acid rain causes irritation in the eyes and skin of human beings. • It may cause corrosion of many buildings, bridges and monuments, railings, fencings etc. • It affects on the enzymatic activities of living being. • Acid rains change the pH of soils and affect the plant growth in various ways. • It inhibits carbon dioxide fixation and photorespiration and adversely affects the productivity of crops.
Acid rain and a Monument The Taj Mahal of Agra is also facing danger from the acid rain because of oil refinery situated at Mathura very close to Agra. This refinery emits smoke and gaseous pollutants including sulfur dioxide. If the sulfur dioxide levels in air increases the resulting acidic precipitation may react with marbles and cause pitting in this wonderful monument that attracts people from all over the world.
Control of Air pollution
What can we DO ?
1. Automobiles must be either made to eliminate use of gasoline and diesel oil or complete combustion is obtained in the engine so that noxious compounds are not emitted. The automobiles, trucks and other transport systems must have an antismog device to minimize pollution. 2. Aforestation, Reforestation 3. Excessive and undesirable burning of vegetation should be stopped.
4. Smoking should be stopped (there is 5,00000 tones tobacco pollution annually). 5. Proper attention should be given by the government and general to make people realize the implications of environmental problem. 6. Legislation should be passed against pollution. 7. Environmental education is the best programme to deal with the environmental problems
