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Air Pollution Sources and Effects Dr. Wesam Al Madhoun

Air Pollution Sources and Effects Dr. Wesam Al Madhoun. What is air pollution?.

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Air Pollution Sources and Effects Dr. Wesam Al Madhoun

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  1. Air Pollution Sources and EffectsDr. Wesam Al Madhoun

  2. What is air pollution? • The presence of any substances in the atmosphere in quantities which are or may be harmful or injurious to human health, welfare, animal or plant life, or property or unreasonably interfere with the enjoyment of life or property.

  3. Outdoor Air Pollution

  4. Primary vs. Secondary Pollutants • Primary- put directly into air from polluting source. • Secondary- when primary combines with other substances in air and creates something more hazardous (acid rain, smog) • Sun often provides energy.

  5. Major Sources of Primary Pollutants Stationary Sources • Combustion of fuels for power and heat. • Other burning such as wood & crop burning or forest fires • Industrial/ commercial processes • Solvents and aerosols Mobile Sources • Highway: cars, trucks, buses and motorcycles • Off-highway: aircraft, boats, farm equipment, and construction machinery.

  6. Natural Sources • Forest fires- ash, particulates, carbon dioxide • Volcanoes- ash, acid mist, hydrogen sulfide • Decaying vegetation- sulfur cmpds • Trees - Volatile Organic Cmpds (VOC’s) • Dust- from storms in arid regions • Gut bacteria- methane gas

  7. Anthropogenic Sources of Air Pollution

  8. Criteria Air Pollutants EPA uses seven "criteria pollutants" as indicators of air quality • Sulfur Dioxide: SO2 • Nitrogen Dioxide: NO2 • Carbon monoxide: CO • Lead: Pb • Particulate Matter: PM10 (PM 2.5) • Volatile Organic Compounds: (VOCs) • Ozone: ground level O3

  9. Sulfur Dioxide (SO2) • Effects: produces acid rain (H2SO4), breathing difficulties, eutrophication due to sulfate formation. • Sources:burning high sulfur coal or oil in power plants, smelting or metals, paper manufacture. • EPA Standard: 0.3 ppm (annual mean) • 2nd largest cause of air pollution-related health damage. (1st is smoking). • Sulfate particles reduce visibility in the U.S. as much as 80%

  10. Sulfur Dioxide Emissions

  11. Nitrogen Dioxide (NO2) • Effects: acid rain, lung and heart problems, decreased visibility (yellow haze), suppresses plant growth • Sources: fossil fuels combustion, power plants, forest fires, volcanoes, bacteria in soil, fertilizers • EPAStandard: 0.053 ppm • Excess nitrogen is causing fertilization & eutrophication of inland waters & seas

  12. Mobile Source Emissions: Nitrogen Oxides

  13. Carbon Monoxide (CO) • Effects: binds tighter to Hemoglobin (Hb) than O2, so organs do not get O2 needed, makes you sleepy, impairs mental functions and visual acuity, even at low levels • Sources:incomplete combustion of fossil fuels 60 - 95% from auto exhaust • EPAStandard: 9 ppm • 1 billion tons enter atmosphere/year

  14. Mobile Source Emissions – CO

  15. Lead (Pb) • Effects: accumulates in tissue; affects kidneys, liver and nervous system (children most susceptible); mental retardation; possible carcinogen; 20% of inner city kids have high levels • Sources: particulates from fuel combustion, smelters, batteries • EPAStandard: 1.5 ug/m3 • Mercury- neurotoxin from coal power plants • Both mercury & lead travel on air currents and fall into aquatic ecosystems causing bioaccumulation & bio-magnification in food webs.

  16. Suspended Particulate Matter (PM10) • Effects: lung damage, carcinogenic. • Sources: burning coal or diesel, volcanoes, factories, unpaved roads, plowing, lint, pollen, spores, burning fields • EPA Standard: 50 ug/m3 (annual mean) • PM2.5 is worse because small enough to be inhaled more deeply • Asbestos fibers & cigarette smoke are most dangerous respirable particles because they are carcinogenic

  17. Mobile Source Emissions: Fine Particulate Matter (PM2.5)

  18. VOCs (Volatile Organic Compounds) • Effects: eye and respiratory irritants; carcinogenic; liver, CNS, or kidney damage; damages plants; lowered visibility due to brown haze; global warming • Sources: vehicles(largest source),evaporation of solvents or fossil fuels, aerosols, paint thinners, dry cleaning, wetlands, rice paddies, bacteria, plants. • Concentrations indoors up to 1000x outdoors

  19. Ozone (O3) • Effects: lung irritant, damages plants, rubber, fabric, eyes • Sources: Created by sunlight acting on NOx and VOC , photocopiers, cars, industry, gas vapors, chemical solvents, incomplete fuel combustion products • Good ozone vs. bad ozone- good is in stratosphere and bad is at ground level (from cars)

  20. Other Air Pollutants • Carbon dioxide- natural source from respiration; human caused from fossil fuels & deforestation • ChloroFluoroCarbons (CFC’s)- from refrigerants, aerosols, Styrofoam • Formaldehyde- building materials & household products • Benzene- paint • Asbestos- car brakes, building materials • Dioxins- pesticides • Cadmium- batteries.

  21. Formation & Intensity of Pollutant is influenced by… • Local climate (inversions, air pressure, temperature, humidity) • Topography (hills and mountains) • Population density • Amount of industry • Fuels used by population and industry for heating, manufacturing, transportation, power • Weather: rain, snow, wind • Buildings (slow wind speed) • Mass transit used

  22. cool air Pollutants cool air warm air (inversion layer) warm air • surface heated by sun • warm air rises (incl. pollutants) • cools off, mixes with air of equal density & disperses • surface cools rapidly (night) • a layer of warm air overlays surface • polluted surface air rises but cannot disperse  remains trapped Thermal Inversion- occur in valleys-pollutant effects are intensified when air cannot move upward due to cold upper air layer

  23. Smog Forms ...when polluted air is stagnant (weather conditions, geographic location)

  24. Urban Heat Islands • Cities are generally 3-5ºC warmer than rural areas • Caused by: • Lack of vegetation to absorb heat • Dark buildings & roads trap heat • Buildings create windbreaks • Dust Dome- trapping of dirt & particulates over city

  25. INDOOR AIR POLLUTION

  26. What are some sources of indoor air pollution? • Cigarette smoke • Deadliest indoor air pollutant • Contain formaldehyde, carbon monoxide • Causes lung cancer. • Second hand smoke may be worse due to particulates that come from tip.

  27. Mold • Moisture in carpets • Allergy symptoms, breathing problems, headache, fatigue

  28. Carbon monoxide • Malfunctioning furnace, gas appliances, cars • Blood cannot carry oxygen • Feel sleepy, nausea, dizzy, cause death.

  29. Asbestos • Roofing, flooring, insulation, brakes • OK… unless disturbed or deteriorates • Can cause asbestosis (scarring of lungs) and meso-thelioma (type of lung cancer) Plaque build up (scarring) in lung w/asbestosis

  30. Lead • Old homes, toys, lead crystal dishes • Causes behavior & learning problems, slow growth, hearing problems, headaches

  31. Formaldehyde • Pressed wood, paneling, particle board, glue. • Respiratory irritation, fatigue, skin rash, known to cause cancer

  32. 8. VOC’s • Paradichlorobenzene- mothballs, insecticides • (perchloroethylene))- dry cleaned clothes • Benzene- paints, cigarettes • Causes respiratory problems, headaches, loss of coordination, nausea, organ damage, cancer

  33. Effects of Air Pollution on… 1. Human Health 2. Plant Health 3. Acid Deposition

  34. 1. Human Health • Depends on intensity & duration of exposure, age & prior health status. • At-risk groups: young, old, or already suffering from respiratory/cardiovascular disease. • Also, more active & outside vs. sedentary inside lifestyle. • Most susceptible- less-developed countries use smoky fires for cooking & heating

  35. Exposure • Time spent in various environments in US and less-developed countries

  36. How is it introduced to body? • Inhalation • Absorption thru skin • Contamination of food & water

  37. How does air pollution affect people? • Chronic bronchitis- coughing, trouble breathing • Asthma- not caused by air pollution, but aggravated by it. • Emphysema- lungs lose elasticity, hard to breathe • Lung Cancer- caused by cigarettes, car exhaust, particulates, asbestos, arsenic, radon

  38. Sick building syndrome- • Buildings closed up to save energy- no circulation • Effects of fumes intensified • Symptoms: headache, eye or throat irritation, cough, itchy skin, dizziness, nausea, fatigue • Feel better when you get fresh air outside. • ≥20% of workers must be afflicted to be classified as SBS

  39. 2. Plant Health • Two Methods of Damage • Directly toxic • Irritate cell membranes • Disruption of plant hormones • Synergistic effects (when combined two are worse than each individually) unpredictable • Air pollutant effects on plants are sometimes confused with insect damage or other diseases.

  40. 3. Acid Deposition

  41. Measuring Acid Rain • Normal rain is slightly acidic and has a pH of about 5.0-5.6 • Any rainfall with a pH value less than 5.0 is defined as acid rain

  42. Two Forms… • Wet Refers to acid rain, fog, sleet, cloud vapor and snow. • Dry Refers to acidic gases and particles.

  43. Increased Acidity • Dry deposited gases and particles can also be washed from trees and other surfaces by rainstorms. • The runoff water adds those acids to the acid rain, making the combination more acidic than the falling rain alone.

  44. Compounds Two main contributors to acid deposition: • Sulfur Dioxide (SO2) • Nitrogen Oxides (NOx) • NO- nitric oxide (or nitrogen monoxide) • NO2- nitrogen dioxide • N2O- nitrous oxide • 66% of all sulfur dioxides and 25% of all nitrogen oxides comes from coal or oil electric power plants. • Most nitrogen oxides come from cars

  45. Effects of Acid Rain • The strength of the effects depend on many factors • How acidic the water is • The types of fish, trees, and other living things that rely on the water • The chemistry and buffering capacity of the soils involved • limestone & basalt have high buffering capacity • have high ANC (Acid Neutralizing Capacity)

  46. Effects of Acid Rain • Has a variety of effects, including damage to forests and soils, fish and other living things, materials, and human health. • Also reduces how far and how clearly we can see through the air, an effect called visibility reduction. • Effects of acid rain are most clearly seen in the aquatic environments • Most lakes and streams have a pH between 6 and 8 http://cica.indiana.edu/projects/Biology/movies.html

  47. Buffering Capacity • Acid rain primarily affects sensitive bodies of water, which are located in watersheds whose soils have a limited “buffering capacity” (places that have granite bedrock or soil for example) • Lakes and streams become acidic when the water itself and its surrounding soil cannot buffer the acid rain enough to neutralize it.

  48. In areas where buffering capacity is low, acid rain also releases aluminum from soils into lakes and streams • aluminum is highly toxic to many species of aquatic organisms. • Can attach to fish gills causing suffocation • Can release from soil particles & enter solutions taken up by plants causing death

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