OUTDOOR & INDOOR AIR POLLUTION

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Presentation transcript:

OUTDOOR & INDOOR AIR POLLUTION

Outdoor Air Pollution

Primary Pollutants Secondary Pollutants Sources Natural Stationary CO CO2 SO2 NO NO2 Most hydrocarbons Most suspended particles SO3 HNO3 H2SO4 H2O2 O3 PANs Most and salts NO3 – Mobile SO4 2

1.All of the following are primary pollutants except iRespond Question Multiple Choice F 184C6DB3-1E6F-2349-B05B-DBBEA516CBCF A.) sulfur dioxide B.) carbon dioxide C.) tropospheric ozone D.) nitrogen oxide E.) particulate matter

2.All of the following countries have ratified the Kyoto Protocol except iRespond Question Multiple Choice F 1403F8AF-4E92-2843-A289-BCF801ECFA3E A.) United States B.) Japan C.) England D.) Canada E.) France

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 for these rxns.

Major Sources of Primary Pollutants Stationary Sources Combustion of fuels for power and heat – Power Plants 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, locomotives, farm equipment, RVs, construction machinery, and lawn mowers

Natural Sources Forest fires- ash, particulates, carbon dioxide Volcanoes- ash, acid mist, hydrogen sulfide Decaying vegetation- sulfur cmpds Trees & bushes- Volatile Organic Cmpds (VOC’s) give Blue Ridge Mtns. their blue hue Pollen Spores Viruses Bacteria Dust- from storms in arid regions Gut bacteria- methane gas

3.Volcanoes, fossil fuel combustion, and fires contribute to pollution in the form of iRespond Question Multiple Choice F 9F6B4AEA-B62E-B647-9A5E-B999FD31C0A0 A.) synthetic compounds B.) DDT C.) EMFs D.) sodium chloride E.) particulates

Anthropogenic Sources of Air Pollution

Criteria Air Pollutants EPA uses six "criteria pollutants" as indicators of air quality Sulfur Dioxide: SO2 Nitrogen Dioxide: NO2 Carbon monoxide: CO Lead: Pb Particulate Matter: PM10 (PM 2.5) Ozone: ground level O3

Sulfur Dioxide (SO2) Properties: colorless gas with irritating odor Effects: produces acid rain (H2SO4), breathing difficulties, eutrophication due to sulfate formation, lichen and moss are indicators Sources: burning high sulfur coal or oil in power plants, smelting or metals, paper manufacture Class: sulfur oxides 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% Reflects sunlight so may have cooling effect

Sulfur Dioxide Emissions See figure 18.5 on page 400

4.The greatest amount of sulfur dioxide emission comes from iRespond Question Multiple Choice F E7D52245-98E6-7C48-A7E3-E496423D3B8C A.) on road vehicles B.) biofuels C.) industrial processes D.) electricity generation E.) fires

Nitrogen Dioxide (NO2) Properties: reddish brown gas, formed as fuel burned in car, strong oxidizing agent, forms Nitric acid (HNO3) in air 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 Class: Nitrogen oxides (NOx) EPA Standard: 0.053 ppm Excess nitrogen is causing fertilization & eutrophication of inland waters & seas

Mobile Source Emissions: Nitrogen Oxides

Carbon Monoxide (CO) Properties: colorless, odorless, heavier than air, 0.0036% of atmosphere 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 Class: carbon oxides (CO2, CO) EPA Standard: 9 ppm 1 billion tons enter atmosphere/year

Mobile Source Emissions – CO

5.The largest source of nitrogen oxide emissions is from iRespond Question Multiple Choice F 60C6015B-F193-5346-9B92-DF8C7E741FFF A.) on road vehicles B.) industry C.) electricity generation D.) biofuels E.) fires

Lead (Pb) Properties: grayish metal 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 Class: toxic or heavy metals EPA Standard: 1.5 ug/m3 2 million tons enter atmosphere/year Mercury- neurotoxin from coal power plants Both mercury & lead travel on air currents and fall into aquatic ecosystems causing bioaccumulation & biomagnification in food webs.

Suspended Particulate Matter (PM10) Properties: particles suspended in air (<10 um) Effects: lung damage, mutagenic, carcinogenic, teratogenic Sources: burning coal or diesel, volcanoes, factories, unpaved roads, plowing, lint, pollen, spores, burning fields Class: SPM: dust, soot, asbestos, lead, PCBs, dioxins, pesticides EPA Standard: 50 ug/m3 (annual mean) PM2.5 is worse b/c small enuf to be inhaled more deeply Asbestos fibers & cigarette smoke are most dangerous respirable particles b/c they are carcinogenic

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

VOCs (Volatile Organic Compounds) Properties: organic compounds (hydrocarbons) that evaporate easily, usually aromatic 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 (Figure 18.8) Class: HAPs (Hazardous Air Pollutants- cause cancer, birth defects, mutation, neutroxins) Methane Benzene Chlorofluorocarbons (CFCs), etc. Concentrations indoors up to 1000x outdoors 600 million tons of CFCs

Ozone (O3) Properties: colorless, unpleasant odor, major part of photochemical smog 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 Class: photochemical oxidants Good ozone vs. bad ozone- good is in stratosphere and bad is at ground level (from cars) Figure 18.10 shows secondary production of urban smog by photochemical rxns in atmosphere

Other Air Pollutants Carbon dioxide- natural source from photosynthesis & 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- smelting, batteries, plastics industry

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

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

Smog Forms ...when polluted air is stagnant (weather conditions, geographic location) Los Angeles, CA

Ultraviolet radiation Solar radiation Photochemical Smog Ultraviolet radiation NO Nitric oxide O Atomic oxygen O2 Molecular oxygen NO2 Nitrogen dioxide H2O Water Hydrocarbons PANs Peroxyacyl nitrates Aldehydes (e.g., formaldehyde) O3 Ozone HNO3 Nitric acid P h o t o c h e m i c a l S m o g

6. A chemical that causes respiratory problems as well as damage to the environment and is a part of photochemical smog is iRespond Question Multiple Choice F 570F2DF6-42F2-8B40-8921-E2D355F61C5A A.) ozone B.) arsenic C.) chlorine D.) asbestos E.) methane

7793A756-7FDF-DF4A-A41C-DCFA772BCED8 7. Which organisms are most affected by air pollution because they obtain their nutrients from the air? iRespond Question Multiple Choice F 7793A756-7FDF-DF4A-A41C-DCFA772BCED8 A.) frogs B.) trees C.) lichens D.) birds E.) bacteria

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

INDOOR AIR POLLUTION

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

What are some sources of indoor air pollution? Mold Moisture in vents, carpets Allergy symptoms, breathing problems, headache, fatigue

What are some sources of indoor air pollution? Carbon monoxide Malfunctioning furnace, gas appliances, cars Blood cannot carry oxygen Feel sleepy, nausea, dizzy, cause death.

What are some sources of indoor air pollution? Radon Colorless, odorless, radioactive gas Comes from soil under basements Long term exposure can cause lung cancer Fix cracks in floor or walls to prevent influx of radon Install ventilation fan in basement to blow radon out. Zone 1 (purple) high levels of radon Zone 3 (yellow) low levels of radon

What are some sources of indoor air pollution? Asbestos Roofing, flooring, insulation, brakes OK… unless disturbed or deteriorates Can cause asbestosis (scarring of lungs) and mesothelioma (type of lung cancer) Plaque build up (scarring) in lung w/asbestosis

What are some sources of indoor air pollution? Lead Old homes, toys, lead crystal dishes Causes behavior & learning problems, slow growth, hearing problems, headaches

What are some sources of indoor air pollution? Formaldehyde Pressed wood, paneling, particle board, glue, deodorizers Respiratory irritation, fatigue, skin rash, known to cause cancer

What are some sources of indoor air pollution? 8. VOC’s Paradichlorobenzene- mothballs, insecticides PERC- dry cleaned clothes Benzene- paints, cigarettes Causes respiratory problems, headaches, loss of coordination, nausea, organ damage, cancer

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

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- LDC use smoky fires for cooking & heating

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

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

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

How does air pollution affect people? 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

2. Plant Health Two Methods of Damage Directly toxic Irritate cell membranes First few days- discoloration due to chlorosis (bleaching) of leaf Later- necrotic (dead) lesions develop leading to death Disruption of plant hormones Ethylene from fossil fuels, chemical plants is a major culprit Synergistic effects (when combined two are worse than each individually) unpredictable White pine seedlings exposed to low levels of O3 & SO2 individually are fine. When combined cause death In alfalfa, O3 and SO2 together are less harmful than individually. Air pollutant effects on plants are sometimes confused with insect damage or other diseases.

Chlorosis and necrosis of white pine needles Necrotic lesions on lower surface of potato leaves Necrosis of watermelon leaf

3. Acid Deposition

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 As of the year 2000, the most acidic rain falling in the US has a pH of about 4.3.

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

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.

Compounds Two main contributers 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

When gas pollutants e.g. sulfur dioxide, nitrogen dioxide dissolve in rain water, various acids are formed. CO2 + H2O  H2CO3 (carbonic acid) SO2 + H2O  H2SO3 (sulfuric acid) NO2 + H2O  HNO2 (nitrous acid) + HNO3 (nitric acid)

sulfuric acid nitric acid indirect health effects Acidic Precipitation Primary Pollutants SO2 NO2 Secondary Pollutants H2SO4 HNO2 sulfuric acid nitric acid acidic precipitation vegetation direct toxicity indirect health effects Fossil fuels Power plants Industrial emissions Auto emissions soils leaching of minerals sediments leaching aluminum

Several processes can result in the formation of acid deposition Several processes can result in the formation of acid deposition. Nitrogen oxides (NOx) and sulfur dioxide (SO2) released into the atmosphere from a variety of sources call fall to the ground simply as dry deposition. This dry deposition can then be converted into acids when these deposited chemicals meet water. Most wet acid deposition forms when nitrogen oxides (NOx) and sulfur dioxide (SO2) are converted to nitric acid (HNO3) and sulfuric acid (H2SO4) through oxidation and dissolution. Wet deposition can also form when ammonia gas (NH3) from natural sources is converted into ammonium (NH4).

Acidic Precipitation Wind Transformation to sulfuric acid (H2SO4) and nitric acid (HNO3) Windborne ammonia gas and particles of cultivated soil partially neutralize acids and form dry sulfate and nitrate salts Wet acid deposition (droplets of H2SO4 and HNO3 dissolved in rain and snow) Dry acid deposition (sulfur dioxide gas and particles of sulfate and nitrate salts) Sulfur dioxide (SO2) and NO Nitric oxide (NO) Acid fog Farm Lakes in deep soil high in limestone are buffered Ocean Lakes in shallow soil low in limestone become acidic

BIOL 349 Atmosphere Fig. 17.10, p. 428

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)

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

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.

aluminum is highly toxic to many species of aquatic organisms. 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 http://home.earthlink.net/~photofish/fish_photos/sw10_thumb.jpg

Effects on Wildlife Loons no longer nesting in Adirondack Mtn lakes- too acidic for fish which they eat Some birds have left areas- no fish, forests destroyed- less nesting space Young of most species are more sensitive to environmental conditions than adults. At pH 5, most fish eggs cannot hatch. At lower pH levels, some adult fish die. Both low pH and increased aluminum levels are directly toxic to fish. Can also stress fish resulting in low body weight, small size, less able to compete for food, habitats, reduced reproduction, increased susceptibility to disease Salmon populations have decreased in Norway since 1950 due to acid rain. Red areas show where populations have declined.

Acid Rain and Forests Acid rain does not usually kill trees directly. Instead, it is more likely to weaken trees by damaging their leaves limit the nutrients available to them expose them to toxic substances slowly released from the soil.

Acid Rain & Forests Trees at higher elevations can be more effected because of increased exposure to acid fog or acid cloud vapor As water evaporates from leaf, acid becomes more concentrated, burning the leaf tissue. Adirondack Mtns

Great Smoky Mountains, NC Effects of Acid Rain Great Smoky Mountains, NC

Effects on Plant Nutrients Acidic water dissolves the nutrients and helpful minerals in the soil and then washes them away before trees and other plants can use them to grow. Acid rain also causes the release of substances that are toxic to trees and plants, such as aluminum, into the soil.

Effects on Property Many statues, monuments, etc. made from limestone (CaCO3), marble or metal Acid rain can dissolve rock or tarnish metal Expensive to restore, refurbish, maintain Car manufacturers now use acid-resistant paint at a cost of $5.00 per new vehicle

8. What heavy metal is produced by the burning of coal? iRespond Question Multiple Choice F 755B73A7-5237-9945-AF15-D313AAF63040 A.) lead B.) mercury C.) arsenic D.) iron E.) titanium

9. Which season will the level of ozone in the Northern Hemisphere be at its lowest? iRespond Question Multiple Choice F F4AAA3EF-7939-4949-9B04-206126F836F0 A.) January B.) March C.) July D.) September E.) December

10. All of the following are responsible for climate change EXCEPT iRespond Question Multiple Choice F A72E3DE4-0239-0440-BEB3-1CBB0E1FD735 A.) CO2 B.) CH4 C.) CFCs D.) SO2 E.) H2O

11. As CFCs enter the stratosphere, they break down ozone molecules 11. As CFCs enter the stratosphere, they break down ozone molecules. Why is this a concern? iRespond Question Multiple Choice F 278CCF46-6913-A04F-A84E-42D961D4CF16 A.) O3 is an important component in oxygen. B.) O3 helps to keep our planet at a stable temperature. C.) O3 is a respiratory irritant in the stratosphere. D.) O3 protects us from damaging UV light. E.) O3 helps to get rid of all the CO2 in the atmosphere.

12. A coal fired power plant produces about the same amount of energy as a nuclear power plant but the nuclear power plant produces more iRespond Question Multiple Choice F EF89EAA0-B9B2-E748-92B7-0154169F47CA A.) CO2 B.) SO2 C.) fly ash D.) particulates E.) thermal pollution