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THE AIR AROUND US

1. TITLE

Air Pollution and The Effects of Air Pollution

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2. INTRODUCTION

What is Air Pollution?

Air is the ocean we breathe. Air supplies us with oxygen which is essential for our bodies to live. Air is 99.9% nitrogen, oxygen, water vapor and inert gases. Human activities can release substances into the air, some of which can cause problems for humans, plants, and animals.

There are several main types of pollution and well-known effects of pollution which are commonly discussed. These include smog, acid rain, the greenhouse effect, and "holes" in the ozone layer. Each of these problems has serious implications for our health and well-being as well as for the whole environment.

One type of air pollution is the release of particles into the air from burning fuel for energy. Diesel smoke is a good example of this particulate matter . The particles are very small pieces of matter measuring about 2.5 microns or about .0001 inches. This type of pollution is sometimes referred to as "black carbon" pollution. The exhaust from burning fuels in automobiles, homes, and industries is a major source of pollution in the air. Some authorities believe that even the burning of wood and charcoal in fireplaces and barbeques can release significant quanitites of soot into the air.

Another type of pollution is the release of noxious gases, such as sulfur dioxide, carbon monoxide, nitrogen oxides, and chemical vapors. These can take part in further chemical reactions once they are in the atmosphere, forming smog and acid rain.

Air pollution can be found both outdoors and indoors. Pollution also needs to be considered inside our homes, offices, and schools. Some of these pollutants can be created by indoor activities such as smoking and cooking. We spend about 80-90% of our time inside buildings, and so our exposure to harmful indoor pollutants can be serious. It is therefore important to consider both indoor and outdoor air pollution.

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3. FINDING

Air Pollution caused by industrial activities

Before flue gas desulfurization was installed, the emissions from this power plant in New Mexico contained excessive amounts of sulfur dioxide.

Smog in big cities

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Air Pollution caused by vehicles

Air Pollution ( Natural and Manufactured)

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Air Pollution (Indoor Pollution)

Air Pollution caused by fire

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Air pollution from World War II production.

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4. DISCUSSION

(a) Examples of air pollutants

Noise Pollution

Noise pollution or unwanted sounds that are carried by the air, have an irritating and detrimental effect on humans and other animals. Careful planning of streets and biuldings in towns and better control over noisy vechiles may add to the control of noise pollution.

Tobacco Smoke

Tobacco smoke is one of the major forms of pollution in buildings. It is not only the smoker who is infected, but everyone who inhales the polluted air. There is a very strong connection between smoking and lung cancer. Bronchitis is common among smokers and unborn babies of mothers who smoke also suffer from the harmful effects of smoking.

Exhaust Gases of Vehicles

Pollution from exhaust gases of vehicles is reponsible for 60% of all air pollution and in cities up to 80%. There is a large variety of harmful chemicals present in these gases, with lead being one of the most dangerous.

Combustion of Coal

The combustion of caol without special precautions can have serious consequences. If winds do not blow away the poisonous gases, they can have fatal effects and may lead to death.

Acid rain

Acid rain is the term for pollution caused when sulfur and nitrogen dioxides combine with atmospheric moisture to produce highly acidic rain, snow, hail, or fog. The acid eats into the stone, brick and metal articles and pollutes water sources. Coal in South Africa is rich in sulphur and the power stations in the Mpumalanga Province could be reponsible for acid rain over other areas of our country.

(b) The sources of air pollutants

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Sources of Air Pollution There are many natural sources of air pollution such as eruption of volcanoes, biological decay and lightning-caused forest fire. Naturally, the Earth already has its own air pollution loading. However, industrialization or just everyday routines has become added burden to the existing air pollution loading. Sources of air pollution are as explained below :-

Industrial and development activities

Malaysia’s economic growth is mainly based on its manufacturing (especially electronics), chemical and rubber industries. But higher production rates also lead to higher emissions of organic and inorganic gases, chemicals and dust.

Different industries emit different pollutants. For example, the chemical industry releases emissions that contain many nitrogen and sulphur compounds while refineries discharge sulphur dioxide and hydrocarbons. The metal working industry is partially responsible for the emissions of sulphur dioxide and large amounts of toxic dust. Human activities have resulted in harmful substances and polluting emissions being released into the air. They endanger our health and our natural ecosystem, and lead to an additional greenhouse effect. (Text : 'Clean Air For Our Cities, 2006, by DOE Malaysia & German Technical Co-operation)

Besides emissions of toxic dust, unplanned and uncontrolled development of industrial premises or zones leads to noise pollution and vibration disturbance. The use of conventional piling methods and the sound of exhaust fans in factories are some of the common activities that generate high sound level.

Motor vehicles

Modern society is highly dependent on motorized transportation such as cars, trucks, and railways. Movement of people and goods requires energy which relies mostly on the burning of fossil fuels, thus causing emissions and noise with adverse local effects.The air quality of the different transport modes depends on the kind of energy, engine technology and the amount of energy consumed. Within the transport sector motorized road traffic is the main emission source while public transport is environmentally friendlier than passenger cars.

In 2004, nearly 14 million vehicles were registered in Malaysia, almost double the number from a decade ago.The number will increase in the next few years, with higher disposable incomes, rural-urban migration and the lack of efficient public transport systems. (Text : 'Clean Air For Our Cities, 2006, by DOE Malaysia & German Technical Co-operation)

Power Generation

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Most of the energy is produced in conventional power plants burning fossil fuels like natural gas, oil or coal. The effectiveness of these power plants is about 35 to 40 per cent with the remaining chemical energy converted into heat.At the moment, Malaysia produces 86% of its electricity in conventional power plants and 14% in hydroelectric power plants.(Text : 'Clean Air For Our Cities, 2006, by DOE Malaysia & German Technical Co-operation)

Everyday Routine

Household contribute to air pollution mainly through the use of energy that is required to run machines and electrical appliances such as refrigerators. Refrigerators and air conditioners not only consume energy but they pollute the environment when their coolant fluids release Chlorofluorocarbon (CFC) into the atmosphere. Chemicals used in houses and gardens are also sources of pollution as well as toxic waste. (Text : 'Clean Air For Our Cities, 2006, by DOE Malaysia & German Technical Co-operation)

Open Burning

Burning of older existing plantations for re-planting creates large amounts of soot particles. These soot particles can be blown over long distances and are mainly responsible for the haze that often covers the sky above Malaysia. These fires not only pollute the air but also destroy the rich habitat of the flora and fauna.

(c) The effects of air pollutions

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Effects on Health and the Environment

Like photochemical pollutants, sulfur oxides contribute to the incidence of respiratory diseases. Acid rain, a form of precipitation that contains high levels of sulfuric or nitric acids, can contaminate drinking water and vegetation, damage aquatic life, and erode buildings. When a weather condition known as a temperature inversion prevents dispersal of smog, inhabitants of the area, especially children and the elderly and chronically ill, are warned to stay indoors and avoid physical stress. The dramatic and debilitating effects of severe air pollution episodes in cities throughout the world—such as the London smog of 1952 that resulted in 4,000 deaths—have alerted governments to the necessity for crisis procedures. Even everyday levels of air pollution may insidiously affect health and behavior. Indoor air pollution is a problem in developed countries, where efficient insulation keeps pollutants inside the structure. In less developed nations, the lack of running water and indoor sanitation can encourage respiratory infections. Carbon monoxide, for example, by driving oxygen out of the bloodstream, causes apathy, fatigue, headache, disorientation, and decreased muscular coordination and visual acuity.

Air pollution may possibly harm populations in ways so subtle or slow that they have not yet been detected. For that reason research is now under way to assess the long-term effects of chronic exposure to low levels of air pollution—what most people experience—as well as to determine how air pollutants interact with one another in the body and with physical factors such as nutrition, stress, alcohol, cigarette smoking, and common medicines. Another subject of investigation is the relation of air pollution to cancer, birth defects, and genetic mutations.

A recently discovered result of air pollution are seasonal “holes” in the ozone layer in the atmosphere above Antarctica and the Arctic, coupled with growing evidence of global ozone depletion. This can increase the amount of ultraviolet radiation reaching the earth, where it damages crops and plants and can lead to skin cancer and cataracts. This depletion has been caused largely by the emission of chlorofluorocarbons (CFCs) from refrigerators, air conditioners, and aerosols. The Montreal Protocol of 1987 required that developed nations signing the accord not exceed 1986 CFC levels.

What are the main environmental effects of air pollution?

Acid deposition

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Acid deposition is not merely characterized as acid rain; it can also be snow and fog or gas and dust. Acid deposition mainly forms during fossil fuel combustion. When emissions of sulphur dioxide and nitrogen oxides come in contact with water, they will become sulphuric acid and nitric acid.

When acidifying agents, such as sulphur dioxide, nitrogen oxides and ammonia, end up in plants, surface water and soils, this has a number of consequences:

- Availability of nutrients and metal spores is likely to decrease.

- When acidity is high more metals will dissolve in water. This can cause surface water to become polluted, which has serious health effects on aquatic plants and animals. For example, high aluminum (Al) concentrations can complicate nutrients uptake by plants. This makes aluminum one of the prior causes of forest decay. Mercury can be dispersed by transport through surface water, causing it to accumulate in fish. Mercury can bio magnify up the food chain, to be taken up by humans eventually.

- Buildings and monuments may be damaged through erosion. Sulphur dioxide breaks down limestone by reacting with calcium carbonate, causing limestone to absorb water during rainfall. Limestone will than fragment.

Eutrophication

Eutrophication is caused by an increase in plant nutrients in water. The higher availability of nutrients causes certain water plants, such as algae and duckweed, to grow so extensively. This blocks sunlight supplies to water. The plants also use all available oxygen supplies, which will not be renewed because heterotrophic plants and bacteria need light to perform photosynthesis. Eutrophication causes ecosystem disruption. Nitrogen pollutants such as nitrogen oxides and ammonia contribute to this problem.

Smog

Smog is a combination of the words smoke and fog. We can distinguish two separate types of smog, summer smog and winter smog. Photochemical smog, or summer smog, mainly consists of ozone. It is a brown, oxidising fog. The causes of photochemical smog are nitrogen oxides and VOC, which stem from traffic and industries.

 Sources, Health and Welfare Effects for Criteria Pollutants.

Pollutant Description Sources Health Effects Welfare Effects

Carbon Monoxide

Colorless, odorless gas

Motor vehicle exhaust, indoor

Headaches, reduced mental alertness, heart

Contribute to the formation of smog.

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(CO) sources include kerosene or wood burning stoves.

attack, cardiovascular diseases, impaired fetal development, death.

Sulfur Dioxide (SO2)

Colorless gas that dissolves in water vapor to form acid, and interact with other gases and particles in the air.

Coal-fired power plants, petroleum refineries, manufacture of sulfuric acid and smelting of ores containing sulfur.

Eye irritation, wheezing, chest tightness, shortness of breath, lung damage.

Contribute to the formation of acid rain, visibility impairment, plant and water damage, aesthetic damage.

Nitrogen Dioxide (NO2)

Reddish brown, highly reactive gas.

Motor vehicles, electric utilities, and other industrial, commercial, and residential sources that burn fuels.

Susceptibility to respiratory infections, irritation of the lung and respiratory symptoms (e.g., cough, chest pain, difficulty breathing).

Contribute to the formation of smog, acid rain, water quality deterioration, global warming, and visibility impairment.

Ozone (O3)

Gaseous pollutant when it is formed in the troposphere.

Vehicle exhaust and certain other fumes.  Formed from other air pollutants in the presence of sunlight.

Eye and throat irritation, coughing, respiratory tract problems, asthma, lung damage.

Plant and ecosystem damage.

Lead (Pb) Metallic element Metal refineries, lead smelters, battery manufacturers, iron and steel producers.

Anemia, high blood pressure, brain and kidney damage, neurological disorders, cancer, lowered IQ.

Affects animals and plants, affects aquatic ecosystems.

Particulate Matter (PM)

Very small particles of soot, dust, or other matter, including tiny droplets of liquids.

Diesel engines, power plants, industries, windblown dust, wood stoves.

Eye irritation, asthma, bronchitis, lung damage, cancer, heavy metal poisoning, cardiovascular effects.

Visibility impairment, atmospheric deposition, aesthetic damage.

(d) The steps needed to prevent and control air pollution

Air pollution has many disastrous effects that need to be curbed.  In order to accomplish this, governments, scientists and environmentalists are using or testing a variety of methods aimed at reducing pollution.

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In many countries in the world, steps are being taken to stop the damage to our environment from air pollution. Scientific groups study the damaging effects on plant, animal and human life. Legislative bodies write laws to control emissions. Educators in schools and universities teach students, beginning at very young ages, about the effects of air pollution.

The first step to solving air pollution is assessment . Researchers have investigated outdoor air pollution and have developed standards for measuring the type and amount of some serious air pollutants.

Scientists must then determine how much exposure to pollutants is harmful.

Once exposure levels have been set, steps can be undertaken to reduce exposure to air pollution. These can be accomplished by regulation of man-made pollution through legislation. Many countries have set controls on pollution emissions for transportation vehicles and industry. This is usually done to through a variety of coordinating agencies which monitor the air and the environment

There are two main types of pollution control.

Input control involves preventing a problem before it occurs, or at least limiting the effects the process will produce.

Five major input control methods exist.  People may try to restrict population growth, use less energy, improve energy efficiency, reduce waste, and move to non-polluting renewable forms of energy production.  Also, automobile-produced pollution can be decreased with highly beneficial results. Output control, the opposite method, seeks to fix the problems caused by air pollution.  This usually means cleaning up an area that has been damaged by pollution. Input controls are usually more effective than output controls.  Output controls are also more expensive, making them less desirable to tax payers and polluting industries.

Current air pollution control efforts are not all highly effective.  In wealthier countries, industries are often able to shift to methods that decrease air pollution.  In the United States, for example, air pollution control laws have been successful in stopping air pollution levels from rising.  However, in developing countries and even in countries where pollution is strictly regulated, much more needs to be done.

5. CONCLUSION

One of the biggest reasons that we can have poor air quality is from fuel burning cars and factories. If we want to have cleaner air then we can pass laws that will demand that the factories have to pass certain quality test or they can not operate. Also we need to have better emissions with our cars and it is possible within a short period of time to get cars to emit zero emissions. By doing this we will be able to improve air quality and it will make our ozone layer better as well.

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You cannot say enough about having clean air and we can go a period of time without food but if we do not have clean air then we are going to have big problem fast. We have heard how the poor quality has created a problem with our ozone layer. It is important that we always keep quality of our air at the fore front of our fight on global warming. If we make small changes then we can improve it to a point were we would not have any ozone issues at all. It is very possible that the car companies produce cars that have no air pollution at all.

Remember that we need to have good air quality to survive and if we make some changes with our vehicles and our factories then we can create an environment where we can have clean air and reverse global warming. Help to make these changes possible and live in a world that we can be proud of. We can do some everyday things that will help the environment. Make sure that you only have lights on in the room you are in. Another easy way to help is to plant a tree in your yard or to get involved in a tree planting program. Buy pump bottles instead of aerosol cans or you can car pool to school or work. There is no reason why you should have to drive alone when you know about 10 people who are going to the same place you are every single day. Drive slower, this may seem like an odd one but the faster you go the faster your engine works, the more fuel it uses and the more gases that are being put into the air. Just by driving the speed limit or five under you can help to save the environment.

6. REFERENCES

BOOK:

Air and Breathing by Stephen Gislason MD

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ARTICLE:

See R. G. Bond et al., Air Pollution (1972); U.S. Council on Environmental Quality, Environmental Quality (22d Annual Report, 1991); World Bank, World Development Report (1992).

INTERNET:

http://www.articlesbase.com/environment-articles/help-clean-up-air-pollution-can-we- improve-air-quality-by-reducing-pollution-994121.html#ixzz0uDJze0K6

http://www.lenntech.com/faq-air-pollution.htm#ixzz0uDCyCmgF

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