AIR POLLUTION
AIR POLLUTION
I. Air Pollution and Health A. Define air pollution: •When concentrations of normal components of air plus new components reach levels that cause damage. B. How much air do we inhale daily? 20,000 liters or 21,200 quarts Or 708 cubic feet (equivalent to a 10 ft. x 10ft. Room with an 8 ft. ceiling.)
AIR POLLUTION
I. Air Pollution and Health C. How much lung surface do we expose with each breath? • Surface area equal to a tennis court
AIR POLLUTION
I. Air Pollution and Health D. What is the normal composition of air? • 78% Nitrogen (N2) • 21% Oxygen (O2) • 1% Carbon dioxide (CO2), and others. E. Repeated exposure to even trace amounts of air pollutants can result in damage to: • Lung tissue • Plants • Buildings • Metals F. How many premature human deaths are associated with air pollution? 1. Worldwide 2.4 million per year (1.5 mm from indoor) 500,000 per year 2. USA
AIR POLLUTION
I. Air Pollution and Health G. Effects of air pollution on human health. 1. Chronic bronchitis: a persistent inflammation of the mucous membranes of the trachea and bronchi. • Loss of cilia • Affects cigarette smokers most • 20% of American males 40-60 years affected most
AIR POLLUTION
I. Air Pollution and Health G. Effects of air pollution on human health. 1. Emphysema: damage to the lung tissue so the air can’t be expelled. Individual may die from suffocation or heart failure. • Cigarette smokers have a 4x – 25x greater risk • Kills more people annually than lung cancer
AIR POLLUTION
I. Air Pollution and Health G. Effects of air pollution on human health. 1. Lung cancer: abnormal, runaway growth of cells in the mucous membranes of the bronchial passages. • Fibrous tumors block passageways causing sections of the lungs to collapse – leading to infection. • Black lung – coal mining • Brown lung – farmers
AIR POLLUTION
II. Major Classes of Outdoor Air Pollutants A. Carbon oxides (COx) 1. CO2 – Carbon dioxide 2. CO – Carbon monoxide
Linked to greenhouse effect & global warming: cars, industry, farming.
B. Sulfur oxides (SOx) 1. SO2 – sulfur dioxide 2. SO3 – sulfur trioxide
Linked to acid rain – fossil fuels.
C. Nitrogen oxides (NOx) 1. NO – nitric oxide 2. NO2 – nitrogen dioxide 3. NO3 – nitrous oxide
Linked to acid rain – liquid fossil fuels.
AIR POLLUTION
II. Major Classes of Outdoor Air Pollutants D. VOC’s • Methane – benzene – chloroform • Butane – benzopyrene – carbon tetrachloride • Ethylene – formaldehyde
Chloroform Trichloroethane Benzene Styrene Xylene
Carbon Tetrachloride Dichlorobenzene Ethyl Benzene Trichloroethylene Tetrachloroethylene
Analysis of Exhaled Breath of 355 Urban Residents
AIR POLLUTION
II. Major Classes of Outdoor Air Pollutants E. Suspended particulate matter (SPM) • Solid particles: dust, soot (carbon), asbestos, lead, cadmium, chromium, arsenic, beryllium, nitrate salts. • Liquid droplets: sulfuric acid, nitric acid, oil, pesticides.
AIR POLLUTION
II. Major Classes of Outdoor Air Pollutants F. Photochemical oxidants: these are formed in the air by the reaction of oxygen, nitrogen oxides and VOC’s under the influence of sunlight.
AIR POLLUTION
III. Primary and Secondary Air Pollutants A. Primary air pollutants 1. Define: Harmful chemicals that enter the air directly from natural and/or human activities. 2. Examples: • CO, CO2, SO2, methane, etc. • From volcanoes, forest fires, industry, farming, cars.
AIR POLLUTION
III. Primary and Secondary Air Pollutants A. Secondary air pollutants 1. Define: Harmful chemicals FORMED IN the air through chemical reactions.
AIR POLLUTION
III. Primary and Secondary Air Pollutants A. Secondary air pollutants 1. Define: Harmful chemicals FORMED IN the air through chemical reactions. 2. Examples: (Acid rain) • SO2 + O2 SO3 + H2O H2SO4 (sulfuric acid)
AIR POLLUTION
III. Primary and Secondary Air Pollutants A. Secondary air pollutants 1. Define: Harmful chemicals FORMED IN the air through chemical reactions. 2. Examples: (Acid rain) • SO2 + O2 SO3 + H2O H2SO4 (sulfuric acid)
III. Primary and Secondary Air Pollutants
AIR POLLUTION
Acid Rain Damage in Washington, D.C.
AIR POLLUTION
IV. Indoor Air Pollution A. B. C. D.
Tobacco smoke Formaldehyde – from furniture, stuffing, paneling, insulation. Asbestos Methylene chloride – paint stripper and thinner.
IV. Indoor Air Pollution
AIR POLLUTION
E. Radon 1. 2. 3. 4. 5. 6.
Odorless, colorless radioactive gas that causes 5000 – 20,000 lung cancer deaths per year. Occurs naturally. The radioactive gas seeps into homes around faulty pipe seals or cracks in the foundation and walls. picocurie is the common unit of radioactivity measurement. The ___________ 4 Exposures to radon levels above ________ picocuries /liter will result in a lung cancer risk equivalent to smoking one package of cigarettes a day. Homes Exceeding Safe Levels of Radon (1988 EPA report) a. North Dakota _______ 63% 46% b. Minnesota ________ 26% c. Indiana ________ 7% (Prescott was highest in state.) d. Arizona ________
AIR POLLUTION
V. Air pollution and the Ozone Layer A. What is Ozone? • A form of oxygen (O3 instead of O2) that forms a layer about 11 miles thick 15 miles above the earth’s surface. • Acts as a filter, absorbing harmful ___________ ultraviolet (UV) radiation from the sun.
AIR POLLUTION
V. Air pollution and the Ozone Layer B. What destroys Ozone? CFC’s (chlorofluorocarbons) . • The main culprit are __________________________ • CFC’s are released into the air during manufacture of foam products, from certain refrigerant compounds & from various other sources. • Globally the major sources of CFC’s are: _________ freon , styrofoam , & ___________________ ____________ . aerosol sprays
AIR POLLUTION
V. Air pollution and the Ozone Layer B. What destroys Ozone? • A single chlorine molecule from a CFC molecule can destroy ______________ ozone molecules. 100,000 • CFC molecules can continue to deplete ozone molecules 50 years for more than ___________ after they are released.
V. Air pollution and Greenhouse Effect
AIR POLLUTION
C. Greenhouse Effect • •
Caused by excessive amounts of greenhouse gasses (CO2, CO, methane, etc.) released into the atmosphere from human activities. These gases trap heat from the sun in the atmosphere slowing their release into space.
What are YOU Breathing?
