Human Impact on the Atmosphere Chapters 18 and 19 Living in the Environment, 11th Edition, Miller

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Human Impact on the AtmosphereChapters 18 and
19Living in the Environment, 11th Edition,
Miller

• Advanced Placement Environmental Science
• La Canada High School
• Dr. E

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Pollution Thorpe, Gary S., M.S., (2002).
Barrons How to prepare for the AP Environmental
Science Advanced Placement Exam

• The term Smog (smoke and fog) was first used in
  1905 to describe sulfur dioxide emission
• In 1952, severe pollution took the lives of 5000
  people in London
• It isnt pollution thats harming the
  environment. Its the impurities in our air and
  water that are doing it.
  
  Former U.S. Vice President Dan Quayle

www.aqmd.gov/pubinfo/ 97annual.html
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TheCleanAirAct

• Congress found
• Most people now live in urban areas
• Growth results in air pollution
• Air pollution endangers living things
• It decided
• Prevention and control at the source was
  appropriate
• Such efforts are the responsibility of states
  and local authorities
• Federal funds and leadership are essential for
  the development of effective programs

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Clean Air Act

• Originally signed 1963
• States controlled standards
• 1970 Uniform Standards by Federal Govt.
• Criteria Pollutants
• Primary Human health risk
• Secondary Protect materials, crops, climate,
  visibility, personal comfort

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Clean Air Act

• 1990 version
• Acid rain, urban smog, toxic air pollutants,
  ozone depletion, marketing pollution rights,
  VOCs
• 1997 version
• Reduced ambient ozone levels
• Cost 15 billion/year -gt save 15,000 lives
• Reduce bronchitis cases by 60,000 per year
• Reduce hospital respiratory admission 9000/year

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Outdoor Air Pollution
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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

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54 million metric tons from mobile sources in 1990
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Human Impact on Atmosphere

• Burning Fossil Fuels
• Using Nitrogen fertilizers and burning fossil
  fuels
• Refining petroleum and burning fossil fuels
• Manufacturing

• Adds CO2 and O3 to troposphere
• Global Warming
• Altering Climates
• Produces Acid Rain
• Releases NO, NO2, N2O, and NH3 into troposphere
• Produces acid rain
• Releases SO2 into troposphere
• Releases toxic heavy metals (Pb, Cd, and As) into
  troposphere

www.dr4.cnrs.fr/gif-2000/ air/products.html
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Criteria Air Pollutants

• EPA uses six "criteria pollutants" as indicators
  of air quality
• Nitrogen Dioxide NO2
• Ozone ground level O3
• Carbon monoxide CO
• Lead Pb
• Particulate Matter PM10 (PM 2.5)
• Sulfur Dioxide SO2
• Volatile Organic Compounds (VOCs)
• EPA established for each concentrations above
  which adverse effects on health may occur

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Nitrogen Dioxide (NO2)

• Properties reddish brown gas, formed as fuel
  burnt in car, strong oxidizing agent, forms
  Nitric acid in air
• Effects acid rain, lung and heart problems,
  decreased visibility (yellow haze), suppresses
  plant growth
• Sources fossil fuels combustion _at_ higher
  temperatures, power plants, forest fires,
  volcanoes, bacteria in soil
• Class Nitrogen oxides (NOx)
• EPA Standard 0.053 ppm

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Mobile Source Emissions Nitrogen Oxides
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Ozone (O3)

• Properties colorless, unpleasant odor, major
  part of photochemical smog
• Effects lung irritant, damages plants, rubber,
  fabric, eyes, 0.1 ppm can lower PSN by 50,
• Sources Created by sunlight acting on NOx and
  VOC , photocopiers, cars, industry, gas vapors,
  chemical solvents, incomplete fuel combustion
  products
• Class photochemical oxidants

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Ozone (O3)

• 10,000 to 15,000 people in US admitted to
  hospitals each year due to ozone-related illness
• Children more susceptible
• Airways narrower
• More time spent outdoors

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Mobile Source Emissions Hydrocarbons
Precursors to Ozone
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Carbon Monoxide (CO)

• Properties colorless, odorless, heavier than
  air, 0.0036 of atmosphere
• Effects binds tighter to Hb than O2, 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
• 5.5 billion tons enter atmosphere/year

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Mobile Source Emissions - CO
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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
• Sources particulates, smelters, batteries
• Class toxic or heavy metals
• EPA Standard 1.5 ug/m3
• 2 million tons enter atmosphere/year

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Suspended Particulate Matter (PM10)

• Properties particles suspended in air (lt10 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)

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Mobile Source Emissions Fine Particulate Matter
(PM2.5)
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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,
  smelting or metals, paper manufacture
• Class sulfur oxides
• EPA Standard 0.3 ppm (annual mean)
• Combines with water and NH4 to increase soil
  fertility

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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
• Class HAPs (Hazardous Air Pollutants)
• Methane
• Benzene
• Chlorofluorocarbons (CFCs), etc.
• Concentrations indoors up to 1000x outdoors
• 600 million tons of CFCs

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Other Air Pollutants

• Carbon dioxide
• ChloroFluoroCarbons
• Formaldehyde
• Benzene
• Asbestos
• Manganese
• Dioxins
• Cadmium
• Others not yet fully characterized

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Formation Intensity

• Factors
• 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
• Economics

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Smog Forms
...when polluted air is stagnant (weather
conditions, geographic location)
Los Angeles, CA
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Primary Pollutants
CO
CO2
Secondary Pollutants
SO2
NO
NO2
SO3
Most hydrocarbons
HNO3
H2SO4
Most suspended particles
H2O2
O3
PANs
and
salts
Most
Natural
Sources
Stationary
Mobile
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Photochemical Smog
UV radiation H2O O2
Primary Pollutants NO2 Hydrocarbons
Auto Emissions
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Air Pollution Results
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Indoor Air Pollution
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Why is indoor air quality important?

• 70 to 90 of time spent indoors, mostly at home
• Many significant pollution sources in the home
  (e.g. gas cookers, paints and glues)
• Personal exposure to many common pollutants is
  driven by indoor exposure
• Especially important for susceptible groups
  e.g. the sick, old and very young

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Exposure

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

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House of Commons Select Committee Enquiry on
Indoor Air Pollution (1991)

• There is evidence that 3 million people have
  asthma in the UK and this is increasing by 5
  per annum.
• Overall there appears to be a worryingly large
  number of health problems which could be
  connected with indoor pollution and which affect
  very large numbers of the population.
• The Committee recommends that the Government
  develop guidelines and codes of practice for
  indoor air quality in buildings which
  specifically identify exposure limits for an
  extended list of pollutants

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Sources of Indoor Air Pollutants

• Building materials
• Furniture
• Furnishings and fabrics
• Glues
• Cleaning products
• Other consumer products
• Combustion appliances (cookers and heaters)
• Open fires
• Tobacco smoking
• Cooking
• House dust mites, bacteria and moulds
• Outdoor air

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Important Indoor Air pollutants

• Nitrogen dioxide
• Carbon monoxide
• Formaldehyde
• Volatile Organic Compounds (VOCs)
• House dust mites (and other allergens, e.g. from
  pets)
• Environmental tobacco smoke
• Fine particles
• Chlorinated organic compounds (e.g. pesticides)
• Asbestos and man-made mineral fibres
• Radon

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Health Effects

• Nitrogen dioxide
• Respiratory irritant
• Elevated risk of respiratory illness in children,
  perhaps resulting from increased susceptibility
  to respiratory infection inconsistent evidence
  for effects in adults
• Concentrations in kitchens can readily exceed WHO
  and EPA standards

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Health Effects

• Carbon monoxide
• An asphyxiant and toxicant
• Hazard of acute intoxication, mostly from
  malfunctioning fuel-burning appliances and
  inadequate or blocked flues
• Possibility of chronic effects of long-term
  exposure to non- lethal concentrations,
  particularly amongst susceptible groups

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Health Effects

• Formaldehyde
• Sensory and respiratory irritant and sensitizer
• Possible increased risk of asthma and chronic
  bronchitis in children at higher exposure levels
• Individual differences in sensory and other
  transient responses
• Caution over rising indoor concentrations

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Health Effects

• Volatile Organic Compounds (VOCs)
• Occur in complex and variable mixtures
• Main health effects relate to comfort and
  well-being, but benzene (and other VOCs) are
  carcinogenic
• Concern about possible role of VOCs in the
  aetiology of multiple chemical sensitivity also
  implicated in sick building syndrome

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Health Effects

• House dust mites
• House dust mites produce Der p1 allergen, a
  potent sensitizer
• Good evidence of increased risk of sensitization
  with increasing allergen exposure, but this does
  not necessarily lead to asthma
• Small reductions in exposure will not necessarily
  lead to reduced incidence and/or symptoms
• Indoor humidity is important

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Health Effects

• Fungi and bacteria
• Dampness and mould-growth linked to self-reported
  respiratory conditions, but little convincing
  evidence for association between measured
  airborne fungi and respiratory disease
• Insufficient data to relate exposure to
  (non-pathogenic) bacteria to health effects in
  the indoor environment

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Health Effects

• Environmental tobacco smoke (ETS)
• Sudden infant death syndrome
• Lower respiratory tract illness
• Middle ear disease
• Asthma
• 12 million children exposed to secondhand smoke
  in homes

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Health Effects

• Fine particles
• Consistent evidence that exposure to small
  airborne particles (e.g. PM10) in ambient air can
  impact on human health mechanisms uncertain
• Chronic Obstructive Pulmonary Disease and
  Cardiovascular Disease patients and asthmatics
  probably at extra risk
• Relative importance of indoor sources is unknown

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Health Effects

• Radon
• Can cause lung cancer
• Estimated that 7,000 to 30,000 Americans die each
  year from radon-induced lung cancer
• Only smoking causes more lung cancer deaths
• Smokers more at risk than non-smokers

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Radon Risk Non-Smoker
Radon Level (pCI/L) If 1000 people who did not smoke were exposed to this level over a lifetime.. About X would get lung cancer This risk of cancer from radon exposure compares to What to do
20 8 Being killed in a violent crime Fix your home
10 4 Fix your home
8 3 10x risk of dying in a plane crash Fix your home
4 2 Risk of drowning Fix your home
2 lt1 Risk of dying in a home fire Fix your home
1.3 lt1 Average indoor radon level Fix your home
0.4 lt1 Average indoor radon level Fix your home
If you are a former smoker, your risk may be
higher
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Radon Risk Smoker
Radon Level (pCI/L) If 1000 people who smoke were exposed to this level over a lifetime.. About X would get lung cancer This risk of cancer from radon exposure compares to What to do Stop smoking and
20 135 100x risk of drowning Fix your home
10 71 100x risk of dying in a home fire Fix your home
8 57 Fix your home
4 29 100x risk of dying in a plane crash Fix your home
2 15 2x the risk of dying in a car crash Fix your home
1.3 9 Average indoor radon level Fix your home
0.4 3 Average indoor radon level Fix your home
If you are a former smoker, your risk may be lower
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Radon

• 55 of our exposure to radiation comes from radon
• colorless, tasteless, odorless gas
• formed from the decay of uranium
• found in nearly all soils
• levels vary

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(From http//www.epa.gov/iaq/radon/zonemap.html)
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Radon How it Enters Buildings

• Cracks in solid floors
• Construction joints
• Cracks in walls
• Gaps in suspended floors
• Gaps around service pipes
• Cavities inside walls
• The water supply

http//www.epa.gov/iaq/radon/pubs/citguide.htmlho
wdoes
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Radon Reducing the Risks

• Sealing cracks in floors and walls
• Simple systems using pipes and fans
• More information http//www.epa.gov/iaq/radon/pub
  s/consguid.htmlreductiontech

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• Sick Building Syndrome (SBS)
• vs
• Building Related Illness (BRI)

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Sick Building Syndrome

• A persistent set of symptoms in gt 20 population
• Causes(s) not known or recognizable
• Complaints/Symptoms relieved after exiting
  building

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Complaints/Symptoms

• Headaches
• Fatigue
• Reduced Mentation
• Irritability
• Eye, nose or throat irritation

• Dry Skin
• Nasal Congestion
• Difficulty Breathing
• Nose Bleeds
• Nausea

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Building Related Illness

• Clinically Recognized Disease
• Exposure to indoor air pollutants
• Recognizable Causes

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Clinically Recognized Diseases

• Pontiac Fever Legionella spp.
• Legionnaire's Disease
• Hypersensitivity Pneumonitis
• Humidifier Fever
• Asthma
• Allergy
• Respiratory Disease
• Chronic Obstructive Pulmonary Disease

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Ventilation
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Movement of Air Into / Out of Homes

• Amount of air available to dilute pollutants
• important indicator of the likely contaminant
  concentration
• Indoor air can mix with outside air by three
  mechanisms
• infiltration
• natural ventilation
• forced ventilation

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Movement of Air Into / Out of Homes

• Infiltration
• natural air exchange that occurs between a
  building and its environment when the doors and
  windows are closed
• leakage through holes or openings in the building
  envelope
• pressure induced
• due to pressure differentials inside and outside
  of the building
• especially important with cracks and other
  openings in wall

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Movement of Air Into / Out of Homes

• Natural ventilation
• air exchange that occurs when windows or doors
  are opened to increase air circulation
• Forced ventilation
• mechanical air handling systems used to induce
  air exchange using fans and blowers
• Trade-offs
• cut infiltration to decrease heating and cooling
  costs vs. indoor air quality problems

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Movement of Air Into / Out of Homes

• Infiltration rates
• Influenced by
• how fast wind is blowing, pressure differentials
• temperature differential between inside and
  outside of house
• location of leaks in building envelope

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Air Pollution Prevention
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Specific Air Pollution Treatment Technology

• Traditional
• Move factory to remote location
• Build taller smokestack so wind blows pollution
  elsewhere
• New
• Biofiltration vapors pumped through soil where
  microbes degrade
• High-energy destruction high-voltage electricity
  
• Membrane separation diffusion of organic vapors
  through membrane
• Oxidation High temperature combustor

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Absorption
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Adsorption
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Combustion
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Cyclone
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Filtration
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Electrostatic Precipitator
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Liquid Scrubber
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Sulfur Dioxide Control
http//www.apt.lanl.gov/projects/cctc/factsheets/p
uair/adflugasdemo.html