Presentation on theme: "What Causes Air Pollution?"— Presentation transcript:
1What Causes Air Pollution? Chapter 12- AIRWhat Causes Air Pollution?
2What causes air pollution? Clean air: Mostly N & O, small amounts of argon, CO2 and H2O.Air pollution- harmful substances in the unhealthy levels.Most from human activitiesNatural sources: volcanoes, dust, pollen and spores
3Primary and Secondary Pollutants Primary pollutants are put directly into air by human activitySecondary pollutants form when primary pollutants come in contact with each other naturally occurring substances.Ex: Ground level ozone- Emissions from cars and natural sources mix with oxygen and react with UV rays.
6Sources of Primary Air Pollutants Particulate matter- Fine and coarse particlesFrom cement plants, mining, incinerators, wood-burning fireplaces, fields, and roadsVolatile Organic Compounds (VOCs)- Carbon monoxide, nitrogen oxide, sulfur dioxide, and chemicalsFrom household products, power plants, and motor vehicles
7The History of Air Pollution 2000 years ago, Roman philosopher, Seneca, complained of foul air.1273, King Edward I made burning sea-coal illegalWorse today due to burning of fossil fuels
8Motor Vehicle Emissions 1/3 of air pollutionClean Air Act, 1970 & 1990, gives EPA authority to regulate vehicle emissionsReduce lead in gasolineCatalytic converters35% more fuel efficient with 95% fewer emissions than 30 years ago
9Motor Vehicle Emissions California Zero-Emission Vehicle Program1990, CA Air Resources Board est. ZEV prgm.Vehicles w/ no tail pipe emissions and no emission control systems that deteriorate over timeBy 2016, 16% of vehicles sold in CA will be ZEVElectricAdvanced batteriesHydrogen fueledLow emission carsHybrid electric carsMethanol fueled cars
10Industrial Air Pollution Clean Air Act requires many industries to use scrubbers or other pollution-control devicesElectrostatic precipitators- Remove dust particles from smoke stacksRemove 20 million tons of ash from coal plants each yearScrubbers- Remove harmful chemicals from gases by spraying them with water.Ex: Removal of ammonia
11Industrial Air Pollution Temperature Inversions- The air above is warmer than the air below, trapping air pollution near the earth’s surfaceCities in valleys or surrounded by mountains (Ex: L.A.)Smog- Air pollution that hangs over urban areas and reduces visibilityMain cause: pollutants released by vehicles and industryL.A., Denver, and Phoenix
12Air, Noise, and Light Pollution Chapter 12-AIRAir, Noise, and Light Pollution
13Short-Term Effects of Air Pollution HeadacheNauseaIrritation to eyes, nose, and throatTightness in chestCoughingUpper respiratory infectionWorsen emphysema and asthma
14Long-Term Health Effects of Air Pollution EmphysemaLung cancerHeart diseaseWorsen various medical conditions
15Indoor Air PollutionAir quality in buildings can be worse than outside due to substances found in carpet, furniture, paint, etc.Ventilation is key to controllingSick-building syndrome- Buildings that are securely sealed and harbor mold, fungi, etc.Common in hot or cold areas
16Indoor Air Pollution Radon gas- Colorless, tasteless, and odorless Produced by decay of UraniumSeeps up through cracks and holes where it adheres to dustDestroys genetic material in lung cells2nd-leading cause of lung cancer
17Indoor Air PollutionAsbestos- Long, thin fibers valued for their strengthUsed as insulation and fire retardantBanned in early 1970sCut and scar lungs- AsbestosisTrouble breathingEventual heart failure
18Noise Pollution Sound measured in decibels (dB) Intensity-loudness120 dB causes pain with continuous exposure causing permanent deafnessUnneeded noise can cause health problemsLoss of hearingHigh blood pressureStress
19Light Pollution No direct hazard to human health Inefficient lighting diminishes view of night skyInefficient lighting is energy wasteLight directed upward is lost into spaceDownward light is bestEnergy efficient light includes:Not using when not neededLow pressure sodium sources
21Acid PrecipitationPrecipitation such as rain, sleet, or snow with a high concentration of acidsSulfur and nitrogen oxides released when fossil fuels are burnedSulfuric and nitric acid fall as acid rainPollutes water sourcesKills living things
22pH Scale Power of hydrogen From 0 to 14 Acidic from 0 to 6 (lower more acidic)Acid rain 5 and below; varies in different geographic areasNormal rain contains carbonic acid at pH of ~ 6Basic from 8 to 14 (higher more basic)7 is neutral (pure water)
23Affects Soils and Plants Acidification- Increase in amount of acid in soil and waterNutrients dissolved and washed awayToxic metals are releasedAluminum causes root damageSulfur dioxide clogs surface openings of plants
25Affects Aquatic Ecosystems pH changes kill aquatic plants, fish, and other aquatic animalsAluminum from soil leaches into water;clogs gills of fishAcidification worse in spring when snow meltsAcid Shock- Sudden increase in acid levelsFish die in large amountsDecreased egg production, hatches, and healthy offspring for amphibians and living fishPowdered limestone (calcium carbonate) neutralizes acid in water sources and soil
27Acid Precipitation and Humans Toxins enter human body through crops, water and fishRespiratory problems in childrenCommercial and sport fishing affected by decreasing number of fishCalcium carbonate dissolves, destroying monuments, etc.
28International Conflict and Cooperation Pollution is put out in a different area from where the acid precipitation may fallEx: S. East Canada gets acid precipitation from OH, IN, IL, PA, MO, WV, and TN pollutionCanada-U.S. Air Quality Agreement- 1991Reduce acidic emissions and acid precipitation