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AIR POLLUTANTS

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AIR POLLUTANTS
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Page 1: AIR POLLUTANTS

AIR POLLUTANTS

Page 2: AIR POLLUTANTS

Air Pollutants An air pollutant is a substance in

the air that can have adverse effects on humans and the ecosystem. The substance can be solid particles, liquid droplets, or gases. A pollutant can be of natural origin or man-made.

Page 3: AIR POLLUTANTS

Types Of Air Pollutants Criteria Pollutants Non- Criteria Pollutants

Page 4: AIR POLLUTANTS

Criteria Air PollutantsIt is a term used to describe air pollutants that have been regulated and are used as indicators of general air quality. The regulations or standards are based on criteria that relate to health and/or environmental effects. Sources of criteria pollutants can either be of natural or man-made.

Page 5: AIR POLLUTANTS

Criteria Pollutants 1:TOTAL SUSPENDED PARTICULATES Small solid or liquid particulates suspended in

the air primarily dust, smoke, metallic and mineral particulates, soot, mist, and acid fumes.

The smaller the particulate, the more deeply it can be inhaled into the lungs, and therefore the greater its potential to affect health

Separate air quality standards are often set for coarse particulates (PM10) and for fine particulates (2.5 microns and lesser in diameter or PM2.5).

Page 6: AIR POLLUTANTS
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Criteria Pollutants 2:SULFUR DIOXIDE

Sulfur dioxide (SO2) is a colorless, toxic, reactive gas emitted from the burning of coal and oil in electrical energy generation or heating or from internal combustion engines.

It is also release in the industrial production of sulfuric acid.

The greatest threat is when combines with water vapor in the air and form sulfuric acid and sulfates.

It is irritating to the respiratory system and when released in massive amounts may increase the atmospheric acidity

Page 8: AIR POLLUTANTS

Criteria Pollutants 3:NITROGEN DIOXIDE When air is heated to high temperature, such as

automobile cylinders or high temperature furnaces of power plants and industrial boilers nitrogen oxides (NOx) are produced..

Nitrogen + OXYGEN = Nitric Oxides -> Nitrogen dioxide

Nitrogen dioxide + RAIN= NITRIC ACID Nitrogen dioxide + HYDROCARBON = SMOG Nitrogen dioxide + SULFUR DIOXIDE = ACID

RAIN Nitrogen dioxide is a brownish, highly reactive

gas present in all urban atmosphere.

Page 9: AIR POLLUTANTS

Criteria Pollutants 4:CARBON MONOXIDE Carbon monoxide (CO) is a colorless, odorless,

and poisonous gas , which is slightly lighter than air.

CO forms when the carbon in fuels does not completely burn. Vehicle exhaust contributes roughly 60% of all CO emissions nationwide and up to 95% in cities.

National guideline values for (CO) are 35μg/Ncm (30 ppm) maximum for one-hour exposure and 10μg/Ncm (9ppm) maximum for 8-hour exposure

Having a role in formation of ground-level ozone.

Page 10: AIR POLLUTANTS

Criteria Pollutants 5:LEAD

Lead (Pb) is a metal found naturally in the environment as well as in manufactured products. Exposure to lead can occur through multiple pathways, including inhalation of air and ingestion of lead in food, water, soil, or dust and can cause various ailments.

Historically, the major sources of lead emissions were motor vehicles and industrial sources.

The major source of lead emissions today is metals processing and the highest levels of lead in air are generally found near lead smelters, waste incinerators, utilities, and lead-acid battery manufacturers.

National guidelines values for lead are 1.5μg/Ncm maximum for three-month exposure and 1.0μg/Ncm maximum for a one-year exposure.

Page 11: AIR POLLUTANTS

Criteria Pollutants 6:OZONE AND RELATED OXIDANTS

Ozone is a gas that forms in the atmosphere when three atoms of oxygen are combined. It is not emitted directly into the air but is created at ground level by a chemical reaction between oxides of nitrogen and volatile organic compounds in the presence of sunlight.

 Bad ozone is an air pollutant that damages human health, vegetation, and many common materials. It is a key ingredient of urban smog.

Page 12: AIR POLLUTANTS

NON CRITERIA POLLUTANTS These are other pollutants that are less

prevalent in the environment. However, these non-criteria pollutants include various hazardous substances that can be a danger to human health. Health risks include cancer, lung damage and damage to the nervous, reproductive and immune systems. Persistent Organic Pollutants (POPs) and heavy metals are two important categories of non-criteria pollutants.

Page 13: AIR POLLUTANTS

Non-Criteria Pollutants Solid and Metals Volatile Organic Compounds Ozone Depleting Substance Greenhouse Gases Radioactive Compounds Odors

Page 14: AIR POLLUTANTS

NON-CRITERIA POLLUTANTSSolid and Metals

It is an incombustible, chemical resistant, fibrous material used for fireproofing materials as well as insulation, building materials, and brake linings.

Asbestos fibers in ambient air pose risk to human health in the form of cancer and other diseases

Page 15: AIR POLLUTANTS

NON-CRITERIA POLLUTANTSSolid and Metals

Some of the deposited mercury ends up in swamps, lake, and streams where bacteria turn in to methyl mercury

Mercury can be absorbed through the skin and mucous membranes and mercury vapors can be inhaled

Heating of mercury, or of compounds of mercury that may decompose when heated, should be carried out with adequate ventilation in order to minimize exposure to mercury vapor.

Page 16: AIR POLLUTANTS

NON-CRITERIA POLLUTANTSSolid and Metals

3.COPPER It is a reddish-colored metal, with a

high electrical and thermal conductivity.

It is insoluble in water. Copper can be released from copper

smelters, are essential to organisms as trace elements, but they are toxic if they are overabundant.

Exposure to slightly higher environmental levels of copper is unlikely to have adverse effects on health. High level exposure might however cause chest pains, vomiting and irritation of the eyes and nose.

Page 17: AIR POLLUTANTS

NON-CRITERIA POLLUTANTSSolid and Metals

A moderately reactive metal that will combine with the oxygen and other non metals and will react with dilute acids to release hydrogen

It is the 4th most common metal in use

In the work place environment zinc contagion can lead to a flu-like condition known as metal fever. This condition will pass after two days and is caused by over sensitivity.

Page 18: AIR POLLUTANTS

NON-CRITERIA POLLUTANTSSolid and Metals

5.CADMIUM A soft, malleable, ductile

bluish-white bivalent which can be easily cut by knife.

Cadmium is not an element that is used by the body, and it is toxic. It mainly affects kidneys and bones. It is also a carcinogen by inhalation. 

Page 19: AIR POLLUTANTS

NON-CRITERIA POLLUTANTSSolid and Metals

It is a silvery white, brittle, fusible, crystalline solid that exhibits poor electrical and heat conductivity properties and vaporizes at low temparture.

Antimony can enter the body by inhalation,by ingestion of food or water containing antimony, or by dermal contact with antimony.

Inhalation of air containing antimony may cause eye and lung irritation, heart and lung damage, stomach pains, diarrhea, vomiting and stomach ulcers.

Page 20: AIR POLLUTANTS

NON-CRITERIA POLLUTANTSSolid and Metals

Arsenic and its compound are used as pesticides, herbicides, insecticides and various alloy.

Naturally occurring sources of human exposure include volcanic ash, weathering of minerals and ores, and mineralized groundwater.

When heated it rapidly oxidizes to arsenic trioxide, which has garlic odor.

Page 21: AIR POLLUTANTS

VOLATILE ORGANIC COMPOUND

are organic chemicals that have a high vapor pressure at ordinary room temperature. Their high vapor pressure results from a low boiling point, which causes large numbers of molecules to evaporate or sublimate from the liquid or solid form of the compound and enter the surrounding air.

Harmful VOCs typically are not acutely toxic, but have compounding long-term health effects. Because the concentrations are usually low and the symptoms slow to develop, research into VOCs and their effects is difficult.

Page 22: AIR POLLUTANTS

VOLATILE ORGANIC COMPOUND

1. Total Hydrocarbons(HCS)-are usually unburned fumes that evaporate from gas tanks and are emitted from exhaust of vehicles.- Can also be the evaporating solvents of asphalts, gaseous emissions of rotting vegetation or the product of any reaction that involves an organic material

Page 23: AIR POLLUTANTS

VOLATILE ORGANIC COMPOUND

2. Aromatic like benzene-emitted by internal combustion engines and is carcinogenic.-It is results from processing of oil to gasoline

Page 24: AIR POLLUTANTS

OZONE-DEPLETING SUBSTANCES

Ozone-depleting substances (ODS) generally contain chlorine, fluorine, bromine, carbon, and hydrogen in varying proportions and are often described by the general term halocarbons

These substances are effective ozone-depleters for two reasons: The first is that they do not break down in the

lower atmosphere - they can remain in the atmosphere from 20 to 120 years or more. 

The second is that they contain either/both chlorine and/or bromine and thus help the natural reactions that destroy ozone. 

Page 25: AIR POLLUTANTS

OZONE-DEPLETING SUBSTANCES

CHLOROFLUOROCARBONS(CFCs)- It is various compounds used as aerosol propellants, solvents, and refrigerants.-when released into the atmosphere contribute to the breakdown of stratosphere ozone layer.

Page 26: AIR POLLUTANTS

GREENHOUSE GASES-a gas that contributes to the greenhouse effect by absorbing infrared radiation

1.CARBON DIOXIDE (CO2)2. METHANE (CH4)3. NITROUS OXIDE (N2O)4. HYDROFUOROCARBON(HFCs),

PERFLUOROCARBON(PCFs), SULFUR HEXAFLUORID(SF6)

Page 27: AIR POLLUTANTS

RADIOACTIVE COMPOUNDS Naturally made

- cosmic radiation from outer space-terrestrial radiation from earth’s crust

Man-made-by the use of radio active materials.

Page 28: AIR POLLUTANTS

ODORS Odors are usually gases from anaerobic,

decomposition of putrescible materials. The problem is most common around dumpsites and landfills, but may also occur around certain chemical plants.


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