1. OUTDOOR & INDOOR AIR POLLUTION

2. Outdoor Air Pollution

3. 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.

4. 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

5. Major Sources of Primary Pollutants
1. 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
2. Mobile Sources
Highway: cars, trucks, buses and motorcycles
Off-highway: aircraft, boats, locomotives, farm equipment, RVs, construction machinery, and lawn mowers

6. 3. Natural Sources Forest fires- ash, particulates, carbon dioxide
Volcanoes- ash, acid mist, hydrogen sulfide, sulfur dioxide
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

7. Anthropogenic Sources of Air Pollution

9. 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

10. 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: 0.14ppm per 24 hours
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

11. Sulfur Dioxide Emissions

12. Nitrogen Dioxide (NO2)
Properties: reddish brown gas (gives smog its brown color), 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 fuel combustion- cars & power plants, forest fires, volcanoes, bacteria in soil, fertilizers
Class: Nitrogen oxides (NOx)
EPA Standard: ppm per 24 hours
Excess nitrogen is causing fertilization & eutrophication of inland waters & seas

13. Mobile Source Emissions: Nitrogen Oxides

14. Carbon Monoxide (CO)
Properties: colorless, odorless, heavier than air, % 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, dizziness, nausea, can lead to death.
Sources: incomplete combustion of fossil fuels % from auto exhaust, cigarettes
Class: carbon oxides (CO2, CO)
EPA Standard: 9 ppm per 8 hours
1 billion tons enter atmosphere/year

15. Mobile Source Emissions – CO

16. 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.
US has unleaded gas now- many other countries don’t

17. 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

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

19. 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
Class: HAPs (Hazardous Air Pollutants- cause cancer, birth defects, mutation, neutroxins)
Methane
Benzene
Chlorofluorocarbons (CFCs), etc.
EPA standards: no standards have been set
Concentrations indoors up to 1000x outdoors
600 million tons of CFCs

20. 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
EPA standard: ppm per 8 hour
Good ozone vs. bad ozone- good is in stratosphere and bad is at ground level (from cars)

22. 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 (industrial glues)
Benzene- paint
Asbestos- car brakes, building materials
Dioxins- pesticides
Cadmium- smelting, batteries, plastics industry

23. 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

24. Thermal Inversion - occur in areas where city is surrounded on 3 sides by mountains or hills, usually ocean or body of water on one side -pollutant effects are intensified when air cannot move upward due to cold upper air layer (Los Angeles, CA)
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

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

26. 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

27. Chemical Rxns in Photochemical Smog
In car engines & power plants:
N2 + O2 → 2NO
NO goes to troposphere:
2NO + O2 → 2NO2 (gives brown color)
NO2 reacts with water vapor in air
3NO2 + H2O → 2HNO3 (nitric acid vapor) + NO
Leftover NO2 reacts with UV radiation
NO2 + UV → NO + O
Highly reactive O combines with O2 to make ozone (O3)
O + O2 → O3

28. 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

29. Effects of Air Pollution on…
1. Human Health
2. Plant Health
What's the Air Pollution Like at Your School?

30. 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

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

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

33. 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

34. 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

35. 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.

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

37. Acid Deposition

38. Measuring Acid Rain
Normal rain is slightly acidic and has a pH of about
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.

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

40. 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.

41. 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

42. 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)

43. 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

44. 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).

45. 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

46. BIOL 349
Atmosphere
Fig , p. 428

47. 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)

48. 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

49. 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.

50. 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, gills secrete excess mucus, causing suffocation
Can release from soil particles & enter solutions taken up by plants causing death

51. 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.

52. 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.

53. 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

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

55. 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.

56. 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

57. INDOOR AIR POLLUTION

58. 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.

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

60. 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.

61. 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

62. What are some sources of indoor air pollution?
Asbestos
Roofing, flooring, insulation, older 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

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

64. 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

65. 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