Chapter 12 - Air

Air Pollution Primary Pollutant Secondary Pollutant Not a new problem for humans Native Americans named Los Angeles Basin “Valley of the Smokes” Two Types of Air Pollutants: Primary Pollutant Secondary Pollutant

Primary Pollutants 5 Major Primary Pollutants These pollutants are released directly into the atmosphere by the activities of humans (and sometimes from nature. Can sometimes be released in sufficient amounts as to cause health concerns . 5 Major Primary Pollutants CO – Carbon Monoxide NOx – Nitrogen Oxides SO2 _- Sulfur Dioxide VOC’s – Volatile Organic Compounds PM – Particulate Matter - Particulates

Carbon Monoxide (CO) Released by the burning of fossil fuels. Transportation is the greatest producer of primary pollutants. Over 70,000 tons per day in US alone just from auto emissions. Poses a health threat in high levels because it lowers the amount of oxygen in your blood.

Man-made Sources of NOx Nitrous Oxides Released from fuel burning in cars, power plants, and industrial boilers. Primarily Nitrogen Monoxide Can cause respiratory diseases (asthma) and cancer. Man-made Sources of NOx

Sulfur Dioxide Is released primarily by burning fossil fuels to produce electricity. Contributes to acid precipitation formation. Contributes to the formation of secondary Pollutants.

Volatile Organic Compounds Released in auto emissions (hydrocarbons), they vaporize and become toxic fumes. Contribute to smog formation and can cause health problems, cancer.

Particulate Matter Are particles of solid or liquid that are smaller than 10 microns (1 millionth of a meter). Agriculture and construction play huge role in formation of particulate matter.

Secondary Pollutants Are formed when primary pollutants interact with naturally occurring substances like sunlight and oxygen. For Example: Ground Level Ozone forms when auto emissions react with sunlight and O2 .

Secondary Pollutants Smog is formed when pollutants from vehicles and industry react with ozone, oxygen, and sunlight CO

Secondary Pollutants Effects of smog can be made far worse by the phenomenon known as Temperature (Thermal) Inversion. occurs when cold air is trapped near the Earth’s surface by warm air above.

Legislation To Improve Air Quality To Reduce Emissions from automobiles: The Clean Air Act of 1970 (strengthened in 1990) gave the EPA (Env. Protection Agency) the authority to regulate emissions from automobiles. Catalytic Converter Banned the use of leaded gasoline lowering the amount of lead in the atmosphere by 90%. Made catalytic converters mandatory on vehicles leading to 35% better fuel efficiency and 95% fewer emissions of pollutants.

Legislation To Improve Air Quality Regulation of Industry Also began with the Clean Air Act of 1970 Resulted in: 1. Scrubbers – use a spray of water to dissolve air pollutants (such as poisonous gas) from industry emissions.

Legislation To Improve Air Quality 2. Electrostatic precipitators - used to remove dust/ash (particulates) from emissions. 22 million metric tons per year removed from coal-fired power plants in the US

Indoor Pollutants Can come from many different sources such as paint, carpet, solvents, and cigarette smoke. Can cause Sick-Building Syndrome in a tightly sealed building with poor air circulation. Pollutants and fungi can cause sicknesses in humans. Causes of Sick-Building Syndrome

Indoor Pollutants Radon Gas Produced by the decay of Uranium in underground bedrock. Gas seeps into the home. Is the 2nd leading cause of lung cancer.

Indoor Pollutants Asbestos A fire resistant fiber-like material used in many buildings. If inhaled, could cause lung tissue scarring and many other problems. US government has spent $40 billion dollars to remove asbestos from schools and government buildings.

Health Problems Associated With Air Pollution Short Term Headache Nausea Bronchitis Pneumonia Long Term Emphysema Lung Cancer Heart Disease

Noise/Light Pollution Noise pollution is considered to be an abundance of unnecessary noise. 120 dB can cause pain Continuous levels above 120dB and one could go deaf Light Pollution an excessive amount of light (usually generated in urban areas) that will obscure our vision. Excessive amounts of light energy is wasted.

Acid Precipitation Is formed when Nitric/Sulfuric Acid is released into the atmosphere through the burning of fossil fuels or excessive amounts of wood. measured by the pH (power of hydrogen) scale which measures acidity Normal pH of rain is 5.6- Considered acid rain if less than 5.6 11= Ammonia (basic) 7= Neutral 2= Lemon Juice (Acidic) Causes $5 billion per year in damages.

Acid Precipitation Can be harmful to soils, aquatic ecosystems, and all organisms. Terrestrial Ecosystems struggle because the producers are facing heavy metals leached from the soil by acid rain. Aquatic Ecosystems can experience acid shock, but can be countered with basic substance. US and Canada signed the US Air Quality Agreement 1991 – pledged to reduce emissions

The End