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Air pollution is the introduction into the atmosphere of chemicals , particulates , or biological materials that cause discomfort, disease, or death to humans, damage other living organisms such as food crops, or damage the natural environment or built environment. The atmosphere is a complex dynamic natural gaseous system that is essential to support life on planet Earth. Stratospheric ozone depletion due to air pollution has long been recognized as a threat to human health as well as to the Earth's ecosystems. Indoor air pollution and urban air quality are listed as two of the Worlds Worst Toxic Pollution Problems in the 2008 Blacksmith Institute World's Worst Polluted Places report Air pollution may be described as contamination of the atmosphere by gaseous, liquid, or solid wastes or by-products that can endanger human health and welfare of plants and animals, attack materials, reduce visibility, or produce undesirable odors. Although some pollutants are released by natural sources like volcanoes, coniferous forests, and hot springs, the effect of this pollution is very small when compared to that caused by emissions from industrial sources, power and heat generation, waste disposal, and the operation of internal combustion engines. Fuel combustion is the largest contributor to air pollutant emissions, caused by man, with stationary and mobile sources equally responsible. The air pollution problem is encountered outdoor as well as indoor. The indoor air pollution came to our attention during 80's while outdoor air pollution has been around for some time. The major pollutants which contribute to indoor air pollution include radon, volatile organic compounds, formaldehyde, biological contaminants, and combustion by-products such as carbon monoxide, carbon dioxide, sulfur dioxide, hydrocarbons, nitrogen dioxides, and particulates. The major pollutants which contribute to outdoor air pollution are sulfur dioxide, carbon monoxide, nitrogen oxides, ozone, total suspended particulate matter, lead, carbon dioxide, and toxic pollutants.

Accidents Caused Due to Air Pollution The public concern is also based on news stories on air pollution accidents and episodes reported by the media. It is important for us to look at these pollution episodes. During a 3 day fog in 1930, 60 people died in Meuse Valley, Belgium, while 592 people died in Manchester, England in 1931 during a 9 day fog. The 1948 plant emissions and atmospheric conditions in Donora, Penn. USA caused a 4 day fog and 7000 people were reported sick and 20 people died. The 4 day fog of 1952 in London, England resulted in 4000 deaths and concentration levels were several times higher than the current air quality standards in the United States. To read the September, 1998, EPA announcement of the final rule to protect Eastern US from Smog. A four hour release of methyl isocyanate at a chemical plant owned by Union Carbide in 1984 killed 2800 people in Bhopal, India and opened the eyes of government agencies and public around the world. This Bhopal gas tragedy can be read in a nutshell in the following table:

Accident Location Year Pollutant Physical Properties of Methyl Isocyanate

Bhopal Gas Tragedy Bhopal, Madhya Pradesh, India 1984 Methyl isocyanate Methyl isocyanate is a colorless liquid that has a sharp odor. The odor threshold for methyl isocyanate is 2.1 ppm. The chemical formula for methyl isocyanate is C2H3NO, and the molecular weight is 57.05 g/mol.

The vapor pressure for methyl isocyanate is 348 mm Hg at 20 C. Pathway # of Deaths Cause of Death Inhalation 2000 Primarily: Pulmonary edema Secondary: Respiratory infections such as bronchitis and bronchial pneumonia. More than 170, 000 survivors Leucorrhea, pelvic inflammatory disease, excessive menstrual bleeding, and suppression of lactation and also stillbirths and spontaneous abortions

Adverse health effects on

Reproductive adverse effects

What is an Air Pollutant? In our daily life we come across many airborne chemicals. Are all these chemicals termed as air pollutants? This question leads one to define an air pollutant. A contaminant that affects human life, plant life, animal life and property or a contaminant which interferes with the enjoyment of life and property could be termed as an air pollutant. Different countries have different legal definitions for an air pollutant. However, the above definition gives us an idea. The Ohio EPA provides the definition of "Air pollutant" or "air contaminant" as particulate matter, dust, fumes, gas, mist, smoke, vapor or odorous substances, or any combination there of. An air pollutant can be defined based on the concentration of chemical present in environment. The composition of clean air (shown in the following figure) is used

as a bench mark. If the concentration of a chemical is above the concentration of chemical present in air, it is then termed as an air pollutant.

There are two basic physical forms of air pollutants. The first is gaseous form. For example, sulfur dioxide, ozone and hydro-carbon vapors exist in the form of a gas. The gases lack definite volume and shape and the molecules are widely separated. The second form of air pollution is particulate matter such as smoke, dust, fly ash and mists. The pollutants are also classified as primary pollutants and secondary pollutants. The primary pollutants remain in the same chemical form as they are released from a source directly into the atmosphere. For example: sulfur dioxide and hydrocarbons. The secondary pollutants are a result of chemical reaction among two or more pollutants. The production of PAN (Peroxyacetyl Nitrate) during photochemical reactions is an example of secondary pollutants.

What causes air pollution? Air pollution can result from both human and natural actions. Natural events that pollute the air include forest fires, volcanic eruptions, wind erosion, pollen dispersal, evaporation of organic compounds and natural radioactivity. Pollution from natural occurrences are not very often. Human activities that result in air pollution include:

1. Emissions from industries and manufacturing activities Have you seen a manufacturing company before? You will notice that there are long tubes (called chimneys) erected high into the air, with lots of smoke and fumes coming out of it. Waste incinerators, manufacturing industries and power plants emit high levels of carbon monoxide, organic compounds, and chemicals into the air. This happens almost everywhere that people live. Petroleum refineries also release lots of hydrocarbons into the air.


Fumes from car exhausts contain dangerous gases such as carbon monoxide, oxides of nitrogen, hydrocarbons and particulates. On their own, they cause great harm to people who breath them. Additionally, they react with environmental gases to create further toxic gases.

3. Household and Farming Chemicals Crop dusting, fumigating homes, household cleaning products or painting supplies, over the counter insect/pest killers, fertilizer dust emit harmful chemicals into the air and cause pollution. In many case, when we use these chemicals at home or offices with no or little ventilation, we may fall ill if we breathe them. What are the common air pollutants around? Carbon Monoxide (CO) Fuel combustion from vehicles and engines. Reduces the amount of oxygen reaching the bodys organs and tissues; aggravates heart disease, resulting in chest pain and other symptoms. Ground-level Ozone (O3) Secondary pollutant formed by chemical reaction of volatile organic compounds (VOCs) and NOx in the presence of sunlight. Decreases lung function and causes respiratory symptoms, such as coughing and shortness of breath, and also makes asthma and other lung diseases get worse. Lead (Pb) Smelters (metal refineries) and other metal industries; combustion of leaded gasoline in piston engine aircraft; waste incinerators (waste burners), and battery manufacturing. Damages the developing nervous system, resulting in IQ loss and impacts on learning, memory, and behavior in children. Cardiovascular and renal effects in adults and early effects related to anaemia.

Nitrogen Dioxide (NO2) Fuel combustion (electric utilities, big industrial boilers, vehicles) and wood burning. Worsens lung diseases leading to respiratory symptoms, increased susceptibility to respiratory infection. Particulate Matter (PM) This is formed through chemical reactions, fuel combustion (e.g., burning coal, wood, diesel), industrial processes, farming (plowing, field burning), and unpaved roads or during road constructions. Short-term exposures can worsen heart or lung diseases and cause respiratory problems. Long-term exposures can cause heart or lung disease and sometimes premature deaths. Sulfur Dioxide (SO2) SO2 come from fuel combustion (especially high-sulfur coal); electric utilities and industrial processes as well as and natural occurances like volcanoes. Aggravates asthma and makes breathing difficult. It also contributes to particle formation with associated health effects

Effects of air pollution on health and environment


This can increase the amount of ultraviolet radiation reaching the earth, where it damages crops and plants and can lead to skin cancer andcataracts. 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. Several more meetings were held from 1990 to 1997 to adopt agreements to accelerate the phasing out of ozone-depleting substances. What are the effects of air pollution? Acidification: Chemical reactions involving air pollutants can create acidic compounds which can cause harm to vegetation and buildings. Sometimes, when an air pollutant, such as sulfuric acid combines with the water droplets that make up clouds, the 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 the leaves of plants. When acid rain infiltrates into soils, it changes the chemistry of the 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 the lakes and streams that the rainwater flows into, harming fish and other aquatic life. Eutrophication: Rain can carry and deposit the Nitrogen in some pollutants on rivers and soils. This will adversely affect the nutrients in the soil and water bodies. This can result in algae growth in lakes and water bodies, and make conditions for other living organism harmful. Ground-level ozone: Chemical reactions involving air pollutants create a poisonous gas ozone (O3). Gas Ozone can affect peoples health and can damage vegetation types and some animal life too. Particulate matter: Air pollutants can be in the form of particulate matter which can be very harmful to our health. The level of effect usually depends on the length of time of exposure, as well the kind and concentration of chemicals and particles exposed to. Short-term effects include irritation to the eyes, nose and throat, and upper respiratory infections such as bronchitis and pneumonia. Others include headaches, nausea, and allergic reactions. Short-term air pollution can aggravate the medical conditions of individuals with asthma and emphysema. Long-term health effects can include chronic respiratory disease, lung cancer, heart disease, and even damage to the brain, nerves, liver, or kidneys. Continual exposure to air pollution affects the lungs of growing children and may aggravate or complicate medical conditions in the elderly. .

Air pollution prevention, monitoring and solution. Solution efforts on pollution is always a big problem This is why prevention interventions are always a better way of controlling air pollution. These prevention methods can either come from government (laws) or by individual actions. In many big cities, monitoring equipment have been installed at many points in the city. Authorities read them regularly to check the quality of air. Let's see more below: Government (or community) level prevention Governments throughout the world have already taken action against air pollution by introducing green energy. Some governments are investing in wind energy and solar energy, as well as other renewable energy, to minimize burning of fossil fuels, which cause heavy air pollution. Governments are also forcing companies to be more responsible with their manufacturing activities, so that even though they still cause pollution, they are a lot controlled. Companies are also building more energy efficient cars, which pollute less than before. Individual Level Prevention Encourage your family to use the bus, train or bike when commuting. If we all do this, there will be less cars on road and less fumes.



Solutions to reduce 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. 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. Simple steps There are simple steps you can take in your everyday life to help improve air quality. Every time you drive to work or school, use your heater or air conditioner, clean your windows or even style your hair, you make choices that can reduce or increase air pollution. On the road In California, about half the air pollution comes from cars and trucks. Fewer trips in your car or truck can help improve air quality. Even how you drive can reduce your cars footprint.Take these into consideration when your are traveling on California roads: 1. Walk or ride a bike when possible. 2. Take public transportation. 3. Organize and condense errands into one trip. 4. When driving, accelerate gradually and obey the speed limit. 5. Drive less, particularly on days with unhealthy air. 6. Maintain your vehicle and keep your tires properly infated. 7. Support the Smog Check Program.

8. Report smoking vehicles to 1-800-END-SMOG. 9. Travel lightly and remove any unnecessary items that may weigh down your vehicle. 10. Limit idling your vehicle to no more than 30 seconds. 11. When in the market for a new car, look for the most effcient, lowest-polluting vehicle or even a zero-emission electric car. At home There are many ways air quality can be improved in the home. By reducing energy consumption, choosing sustainable products and eliminating your exposure to chemicals, we can all contribute to a cleaner California. Reducing energy consumption helps reduce air pollution. If less gasoline, natural gas and electricity (power plants burn fossil fuels to generate electricity) are used, not only do your bills decrease but less pollutants are emitted. There are also many products in the home, garden and garage that emit smogforming chemicals that pollute the air when used. Volatile organic compounds (VOCs) and particulate matter (PM) contained in these products penetrate deep into the lungs and can trigger asthma attacks or worsen respiratory illnesses.The suggestions below will help reduce exposure in your home: 12. Turn the lights off when you leave a room. 13. Replace energy-hungry incandescent lights with compact forescent light bulbs. 14. Ask your energy supplier for a home audit and inquire about alternative energy solutions like solar or wind. 15. Opt for a fan instead of air conditioning. 16. Use a programmable thermostat and set it to 78F in the summer and 68F in the winter. 17. Install low-fow shower heads. 18. Recycle paper, plastic, metals and organic materials.

19. Use an EPA-approved wood burning stove or freplace insert. 20. Dont use your wood stove or freplace on days with unhealthy air. 21. Dont heat your home with a gas stove. 22. Use a surge protector for multiple appliances and turn it off when products are not in use 23. Add insulation to your home. 24. Wash laundry in cold water and line dry. 25. When ready to replace, look for energy star appliances. 26. Use a propane or natural gas barbecue rather than a charcoal one. 27. Microwave or use a toaster oven for small meals. 28. Have your gas appliances and heater regularly inspected and maintained. 29. Use washable dishes, utensils and fabric napkins rather than disposable dinnerware. 30. Choose products that use recycled materials. 31. Eat locally, shop at farmers markets and buy organic products. 32. Buy products from sustainable sources such as bamboo and hemp. 33. Use durable reusable grocery bags and keep them in your car so youre never caught off guard. 34. Paint with a brush instead of a sprayer. 35. Store all solvents in airtight containers. 36. Use an electric or push lawn mower. 37. Use a rake or broom instead of a leaf blower. 38. Use water-based cleaning products that are labeled zero VOC.

39. Insulate your water heater and any accessible hot water pipes. 40. Eliminate use of toxic chemicals at home; opt for natural substitutes. 41. Plant a tree!They flter the air and provide shade. 42. Let your elected representatives know you support action for cleaner air. At Work There are multiple ways of reducing consumption at the workplace. Considering we spend a good portion of every week at the offce, use the suggestions below to keep your workplace environmentally friendly: 43. Carpool. 44. Telecommute. 45. Start a recycling program. 46. Print and photocopy on both sides of paper. 47. Bring your lunch to work to avoid mid-day outings. 48. Turn off offce equipment, computers, printers, and fax machines, after hours. 49. Harness the power of the sun: open the blinds and turn off the lights. 50. Dress for the weather and adjust layers before adjusting the thermostat.