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Learn about air pollution, the different types of pollutants, their sources, and their impact on human health and the environment. Discover ways to reduce air pollution and improve air quality.
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What is Pollution? • Pollution: an unwanted change in an environment caused by the introduction of harmful conditions • Point source pollution: comes from definite source ex-smokestack • Non-point source pollution: source of pollution difficult to pinpoint ex- runoff from land
Primary Vs. Secondary • Primary pollutant: enters the environment as-is; already a pollutant ex: particulates from a smokestack • Secondary pollutant: reacts with other chemicals and becomes a pollutant ex: smog
Air Pollution Can be visible or invisible Anything that is in the air in quantities that are detrimental, whether from manmade or natural activities. Air pollution can travel a long distance and often affects areas where it wasn’t produced Ex- Alaska’s North Slope receives pollution from Europe and Asia due to air currents
Sulfur Oxides Sulfur Oxides ( SOx): • From burning fossil fuels: contributor to acid rain (combines with water to form sulfuric acid), generation of electricity (coal-fired plants), and industry • regulated by Clean Air Act; decreasing • respiratory irritant; also lowers pH of water and harms animal and plant life, structures
Acid Deposition • Sometimes called Acid Rain • Has a pH below 5.6 • It is a regional air pollution problem because cities and towns down wind of coal-burning powerplants often feel the worst affects. • Calcium Carbonate or limestone is often used to help change the pH of soils.
Nitrogen Oxides • Clean Air Act, also decreasing • same health issues as SOx Nitrogen Oxides (NOX): • fossil fuels; vehicle emissions, electricity plants, industry • acid rain contributor (forms nitric acid with water)
Electrostatic Precipitation SOx and NOx are controlled in industry by “scrubbers” : systems that inject a dry reagent or slurry into a dirty exhaust stream to "wash out" acid gases, and charged plates to attract particulate matter.
Carbon Monoxide Carbon Monoxide (CO): • vehicle emissions, construction and heavy equipment, fires, industry • poisonous, causes suffocation, aggravation of respiratory ailments • Regulated by the Clean Air Act
Lead Lead (Pb) • since removed from fuels and other products like paint, levels in air have dropped dramatically • still an issue in older buildings • toxic; accumulates and damages nervous system • regulated under CAA
Ground-level Ozone Ground-level ozone: • created by chem. Rxns b/t oxides of nitrogen (NOx) and volatile organic compounds (VOC) in presence of sunlight • respiratory irritant; can reduce lung function and inflame the linings of the lungs • primary component of smog • reg. by CAA
Smog/Ozone • Formed when volatile organic compounds (like paint fumes) and nitrogen oxides (car exhaust) react in the presence of sunlight . • Children in high-ozone communities developed asthma at a rate three times higher than those in the low-ozone communities. (California study). • Can make those with heart and lung disease more at risk; held near ground by thermal inversions • Crop damage
Particulate Matter ParticulateMatter: alsoknown as particle pollution or PM • mixture of small solid particles and liquid droplets • made up of acid, organic chemicals, metals, and soil or dust particles • effects: respiratory irritant, decreased lung function, lung disease (ex-cancer)
Dust or Particulate Matter • Comes from smokestacks, farmers’ fields, construction sites, quarries, wind erosion • Reduces visibility • Small particles (< 10 μm) can be inhaled • Studies show that over a long period of time, this can cause lung damage
Pollution from fuel burning – factories, power plants, lawn mowers, BBQ grills, forest fires • CO reduces the ability of the blood to carry oxygen, effects central nervous system, causes sluggishness. • NOx contributes to ozone formation, adds nutrients to Chesapeake Bay, acid rain component. • SO2 causes acid rain, may irritate lining of lungs.
Hazardous Air Pollutants • Approximately 188 chemicals on list, including mercury ( from coal plants) lead, formaldehyde • Causes birth defects • Cancer • Burning eyes, lungs, skin • Damage to the environment www.epa.gov/ttn/atw/allabout.html
Indoor Air Pollution Air quality in homes is also a concern- accumulations of dust, dander, mold spores, VOC’s released from furniture, carpets, paints, etc., • as our houses become more energy efficient their air quality can decrease!
Indoor Air Pollutants • Radon – 222 • Asbestos • Formaldahyde • Tobacco Smoke • Carbon monoxide
Radon-222 • Naturally occurring colorless and odorless radioactive gas. • Radon is found in soil and rock surrounding a house foundation. • Long term exposure can cause lung cancer. • If detected, should be vented to outside or source sealed off
Asbestos • A material often found in older house and buildings. Used to insulate pipes, ceiling tiles, and floor tiles. • When asbestos becomes old it is known as friable. • Friable asbestos is dangerous because it can be inhaled into ones lungs and scar the lung tissue causing lung cancer.
Formaldehyde • A colorless, extremely irritating chemical. • Found in many building materials such as plywood, particleboard, paneling, furniture, drapes, adhesives in carpeting.
Tobacco Smoke and Carbon Monoxide • Cigarettes • Cause lung cancer, respiratory ailments, heart disease. • Carbon Monoxide is caused by faulty furnaces, unvented gas stoves and kerosene heaters and wood stoves that don’t burn efficiently.
Regulations to Protect the Air • Industrial Revolution created soot, smoke and other pollutants which caused health problems and many deaths. • Local jurisdictions were responsible for regulating pollution. • 1970 the newly formed Environmental Protection Agency was tasked with the Clean Air Act.
Clean Air Act • Sets standards for air quality (NAAQS) • Based on health studies • Protects the most sensitive people • Requires new sources to use pollution controls • Older sources will eventually get phased out (in theory) • Major sources must show no impact or must reduce pollutants if modifying or expanding
What can you do to reduce air pollution? • Carpool or reduce trips • Do not let your car idle • Use water-based paints, low-VOC solvents • Consider hybrid cars • Conserve electricity • Recycle goods • No open burning • Maintain heaters/AC • Use hand tools for yard work • Buy low-energy appliances • Insulate your home