Transcript Document

AIR POLLUTION
COMPOSITON OF AIR
•
•
•
•
78% Nitrogen (N2)
21% Oxygen (O2)
0.9% Argon
0.035% (CO2)
POLLUTION
• Anything that
negatively
affects the
health,
survival, or
activities of
humans or
other living
organisms.
EFFECTS OF AIR
POLLUTION
• Human Health
– ACUTE: short duration
exposure and/or immediate
effects
Examples:
irritation of eyes, nose and
throat
upper respiratory infections
(bronchitis, pneumonia)
headaches
nausea
allergic reactions, etc.
EFFECTS OF AIR
POLLUTION
• Human Health
– CHRONIC: long
duration exposure
and/or long term effects
Examples:
lung cancer
heart disease
damage to brain,
nerves, liver,
kidneys,
etc.
EFFECTS
OF AIR
POLLUTION
• Aesthetic
EFFECTS
OF AIR
POLLUTION
• Damage to
organisms
Air pollution damage to
spruce and to red alder trees.
Air pollution damage to white pine.
MN. Dept. Nat. Res. Archive
Damage to pine due to S02
MN. Dept. Nat. Res. Archive
EFFECTS
OF AIR
POLLUTION
• Damage to
ecosystems
Spruce forest.
Decline of forests due to air pollution.
EFFECTS
OF AIR
POLLUTION
• Damage to
property
Effects of dry deposition of
sulfur dioxide, which
causes the formation of
gypsum. Gypsum traps
particulate matter to form
heavy, black incrustation.
FACTORS INFLUENCING
EFFECTS
• Chemical Nature
– How active and harmful
• Concentration
– See Temperature Inversions
• Persistence
– How long pollutant stays around
TEMPERATURE
INVERSION
• Normally air temp decreases with increasing
altitude.
– Ground heats up and heats air above it
which rises, expands, and cools.
– This rising air carries pollutants up and
away from where humans breathe and dilute
the pollutants in more air space.
TEMPERATURE
INVERSION
• Temperature Inversion: occurs at ground level when
cool air is created under or slips under relatively
warmer air just above it.
TEMPERATURE
INVERSION
• Temperature Inversion: occurs at ground level when
cool air is created under or slips under relatively
warmer air just above it.
TEMPERATURE
INVERSION
• Temperature Inversion: occurs at ground level when
cool air is created under or slips under relatively
warmer air just above it.
TEMPERATURE
INVERSION
• Temperature Inversions break when
– Sun comes out and heats ground which heats
air above ground to warmer than layer
above it.
– During cloudy weather, sun may not be
strong enough to break up inversion for
several hours or days.
TEMPERATURE
INVERSION
• Temperature Inversions are bad because
– Air pollution concentrates in this layer
that we breathe.
• In 1963, 300 people in NY City died
due to temp inversion.
TEMPERATURE
INVERSION
• Temperature Inversions
– Occur almost every night
– Occur more dramatically in cities near
mountains
• This is why we have smokestacks
SOURCES OF AIR
POLLUTION
• Natural sources include:
– Volcanoes, fires, dust
storms…
Greece 2007
SOURCES OF AIR
POLLUTION
• Human (Anthropogenic)
– Stationary vs. Mobile
• Stationary: e.g., power
plants
• Mobile: e.g.,
transportation
SOURCES OF AIR
POLLUTION
• Primary vs. Secondary
• Primary pollutants: enter air directly as
pollutants – direct products of combustion
and evaporation.
• Secondary pollutants: primary pollutants
that undergo further reactions in
atmosphere to produce additional
undesirable compounds.
PRIMARY VS SECONDARY
TYPES OF AIR
POLLUTANTS
• Criteria Pollutants
– Clean Air Act
mandates NAAQS-national ambient air
quality standards (max
concentrations that can
be in the air).
– SPLONC = SO2,
Particulate Matter,
Lead, O3, NO2, CO
NAAQS
• these are primary
standards intended to
protect human health
SULFUR DIOXIDE: SO2
• Sources: mostly stationary fuel combustion
(esp. coal power plants)
• Main Effects:
– Acid Deposition
– Corrosive
• Damages lungs
• Damages structures
• Damages environment
PARTICULATE MATTER
• Examples: dust, soot, lead, arsenic
• Sources: industry (38%) and stationary
(25%) and mobile (21%) fuel combustion
• Main Effects: depends on pollutant
– Usually decreases lung function
LEAD
• Sources: paints and smelting plants
• Main Effects:
– Affects brain and nervous system
OZONE: O3
• Sources: secondary pollutant from
nitrogen dioxide, hydrocarbons, sunlight
– Mostly transportation; also stationary
fuel combustion
• Main Effects:
– Damages lungs; irritates eyes
– Damages plants
– Damages structures
NITROGEN DIOXIDE: NO2
• Sources: secondary pollutant from nitrogen
oxide
– Mostly fuel combustion (stationary and
transportation)
• Main Effects:
– Acid Deposition
– Forms ozone
– Damages lungs
– Produces brown haze in air
CARBON MONOXIDE: CO
• Sources: mostly transportation
• Main Effects:
– Reduces blood’s capacity to carry
oxygen (headaches and worse)
– Forms ozone
TYPES OF AIR
POLLUTANTS
• Noncriteria Pollutants
– Clean Air Act
mandates emission
standards (how
much can come out
of the smokestack)
– Examples: arsenic,
asbestos, mercury,
radioactive
isotopes.
PRINCIPAL
POLLUTANTS
PRINCIPAL POLLUTANTS
PANs = peroxyacetyl nitrates, highly reactive and damaging compounds.
THERE ARE TWO KINDS
OF SMOG
• Industrial smog (gray smog) occurs where
coal is burned and atmosphere is humid.
• Photochemical smog (brown smog) occurs
where sunlight acts on vehicle pollutants.
TRENDS IN AIR POLLUTION
Health Effects of Air Pollution
Introduction
• Methods of Exposure
• Criteria Air Pollutants:
–Review: NAAQS from CAA
•Primary standards
•Secondary standards
• Hazardous Air Pollutants:
–Regulated under 1990 CAA
Amendments
• Some other important health aspects
–Bioaerosols, medicinal purposes
Exposure
• Chronic
• Acute
– Air Pollution Episode
• Dependent on local conditions
• Epidemiological studies
– Statistical relationship between
environmental factors and human
disease
– Challenging
• Toxicological studies
• Pollutant interactions
Smog Episode in NYC, 1963
National Archives, photo by Chester Higgins
Respiratory System
• Via
inhalation/respiratory as
well as eye/skin
• Three parts of
respiratory system
– Naso-pharyngeal (HAR)
– Tracheo-bronchial (TBR)
– Pulmonary-Alveolar (GER)
• Lungs  portal of entry
– Purpose
– GER SA > 75 m2
Dr. Owens, UF ABE2062 Course
http://faculty.abe.ufl.edu/~chyn/age2062/lect/lect_20/lect_20.htm
Respiratory System
• Natural protection
mechanisms
• Naso-pharyngeal (HAR)
–
–
–
• Tracheo-bronchial (TBR)
– Mucociliary “escalator”
– Bronchial constriction
• Pulmonary-Alveolar (GER)
– Macrophages (phagocytosis)
– No ciliary action
Fisher and Paykel Health Care
http://www.fphcare.com/humidification/foradults2.asp
Criteria Air Pollutants:
Particulate Matter
• Very small solids/liquids that remain suspended
• Causes: materials handling, combustion
processes, gas conversion reactions
• Main sources:
Pollutant
Primary Stds.
Particulate
Matter (PM10)
Revoked(2)
3
150 µg/m
Particulate
Matter (PM2.5)
3
15.0 µg/m
3
35 µg/m
Averaging
Times
Secondary Stds.
Annual(2)
(Arith. Mean)
24-hour(3)
Annual(4)
(Arith. Mean)
24-hour(5)
Same as Primary
Criteria Air Pollutants:
Particulate Matter
• Two possible fates
• Factors affecting fate
– Aerodynamic properties
– Physiological behavior
Adapted from Universite Laval
http://www.theses.ulaval.ca/
2004/21789/ch01.html
Methods of Deposition
Impaction*
Interception*
Diffusion*
Electrostatic Attraction
Gravitational Settling
Criteria Air Pollutants:
Particulate Matter
• Major contributors
– Gravitational Settling
• Predominant for dp  3 m
• 3-5 m (VTS  dar2)
• Distal/horizontal
regions of bronchial
airways
• Primarily in HAR or TBR
• Visual example:
http://aerosol.ees.ufl.edu/respirat
ory/section04-2.html
– Impaction
 PM2.5 regulations
• Visual example:
http://aerosol.ees.ufl.edu/respiratory/se
ction04-1.html
– Brownian diffusion
• Predominant for dp 0.5 m
• Visual example:
http://aerosol.ees.ufl.edu/respiratory/se
ction04-3.html
• Minimal effect
– Electrostatic Attraction
– Interception
• Elongate particles
• Visual example:
http://aerosol.ees.ufl.edu/respirat
ory/section04-4.html
Criteria Air Pollutants:
Particulate Matter
dp<0.1
0.1<dp<1
dp>PM2.5
DF=Total
DFHA=Head Airways
DFTB=Tracheobronchial
DFAL=Alveolar region
• Assume this is for nasal breathing. How might this graph
change for mouth breathing?
Criteria Air Pollutants:
Particulate Matter
• Health effects
– Wheezing and coughing
– Heart attacks and death
Wide Range
• TSP (Total Suspended Particles)
– In presence of SO2, direct correlation between TSP and
hospital visits for bronchitis, asthma, emphysema,
pneumonia, and cardiac disease
– ~60,000 deaths from PM (AHA)
– 1% increase in mortality for every 10 mg/m3 increase in
PM (AHA)
• Respiratory mortality up 3.4% for the same (AHA)
• Cardiovascular mortality up 1.4% for the same (AHA)
Criteria Air Pollutants:
Particulate Matter
• PM10 (<10 m, coarse (2.5-10 m) and fine particles)
– Anything larger deposited in the HAR (nasalpharangycal)
• PM2.5 (<2.5 m, fine particles)
– Most serious health effects in alveolar/gas exchange
region
 shift in regulation focus
– May adsorb chemicals & intensify their effects
– Toxic or carcinogenic – pesticides, lead, arsenic,
radioactive material
• 8% increase in lung cancer for each 10 g/m3 increase of PM2.5
Criteria Air Pollutants:
Particulate Matter
• Asthma
– 14 Americans die/day of asthma
• 3x greater than 20 yrs ago
– Increased health care costs
• Particulate episodes
–
–
–
–
–
Inversions (covered officially later)
In presence of SO2
1930: Meuse Valley in Belgium- 60 deaths
1948: Donora, PA- 20 deaths
1952: “Lethal London Smog”- 12,000 deaths
Criteria Air Pollutants: Carbon
Monoxide
• Colorless, odorless, tasteless gas
 “Silent Killer”
• Review…
– Cause: incomplete combustion
– Source: transportation sector, energy production, residential heating
units, some industrial processes
• Ambient concerns addressed by NAAQS
• OSHA (50 ppm avg over 8-hour period)
Pollutant
Primary Stds.
Averaging
Times
Secondary Stds.
Carbon
Monoxide
9 ppm
8-hour(1)
None
1-hour(1)
None
3
(10 mg/m )
35 ppm
3
(40 mg/m )
Criteria Air Pollutants: Carbon
Monoxide
• Reacts with hemoglobin in blood
– Forms carboxyhemoglobin (HbCO)
rather than oxyhemoglobin (HbO2)
– Prevents oxygen transfer
• Toxic effects on humans
– Low-level: cardiovascular and
neurobehavior
– High-level: headaches/nausea/fatigue
to possible death
– Oxygen deficient people esp. vulnerable
(anemia, chronic heart or lung disease,
high altitude residents, smokers)
• Cigarette smoke: 400-450 ppm; smoker’s
blood 5-10% HbCO vs 2% for non-smoker
CDC CO Poisoning
http://www.cdc.gov/co/faqs.htm
Criteria Air Pollutants: Carbon
Monoxide
• Concern in homes especially - Install
CO monitor!
– No indoor home regulations
• >70 ppm  flu-like symptoms (w/out fever)
• 150-200 ppm  disorientation,
drowsiness, vomiting
• >300 ppm  unconsciousness,
brain damage, death
– 500 Americans die/year from
unintentional CO poisoning
– What are some potential sources
of CO poisoning?
Parrish Medical Center
http://www.parrishmed.com/programs_
services/wound_hyperbaric.cfm
• Treatment: fresh air, oxygen therapy,
hyperbaric chamber
Criteria Air Pollutants: Ozone
• Cause: product of photochemical rxns
• Source: cars, power plants, combustion,
chemical industries
• Acute Health effects
– Severe E/N/T (ear/nose/throat) irritation
– Eye irritation at 100 ppb
– Interferes with lung functions
• Coughing at 2 ppm
• Chronic Health Effects
– Irreversible, accelerated lung damage
Criteria Air Pollutants: NOx
• Cause: Fuel combustion at high temps
• Source: mobile and stationary combustion sources
• Prolonged exposure  pulmonary fibrosis, emphysema,
and higher LRI (lower respiratory tract illness) in children
• Toxic effects at 10-30 ppm
– Nose and eye irritation
– Lung tissue damage
• Pulmonary edema (swelling)
• Bronchitis
• Defense mechanisms
– Pneumonia
– Aggravate existing heart disease
Criteria Air Pollutants: SOx
•
•
•
•
•
Cause: Burning fuel that contains sulfur
Source: Electric power generation, diesel trucks
Gas and particulate phase
Soluble and absorbed by respiratory system
Short-term intermittent exposures
– Bronchoconstriction (temporary breathing difficulty)
– E/N/T irritation
– Mucus secretion
• Long-term exposures
– Respiratory illness
– Aggravates existing heart disease
• Intensified in presence of PM
– London issues were combination of the two
Criteria Air Pollutants: Lead
(Pb)
• Source: burning fuels that contain lead
(phased out), metal processing, waste
incinerators
• Absorbed into blood; similar to calcium
• Accumulates in blood, bones, muscles,
fat
– Damages organs – kidneys, liver, brain,
reproductive system, bones (osteoporosis)
– Brain and nervous system – seizures, mental
retardation, behavioral disorders, memory
problems, mood changes,
• Young children - lower IQ, learning disabilities
– Heart and blood – high blood pressure and
increased heart disease
– Chronic poisoning possible
Queensland Government Environmental Protection
Agency
http://www.epa.qld.gov.au/environmental_managem
ent/air/air_quality_monitoring/air_pollutants/airborne
_lead/
Criteria Air Pollutants: Air
Quality Index (AQI)
• Do we have a way to determine local air
quality? AQI/PSI (formerly Pollutants Std
Index)
• Assigns numerical rating to air quality of six
criteria pollutants (TSP, SO2, CO, O3, NO2,
and TSP*SO2)
API Value
Air Quality Descriptor
0-50
Good
51-100
Moderate
101-199
Unhealthful
200-299
Very unhealthful
300
Hazardous
Criteria Air Pollutants: Air
Quality Index (AQI)
• Begin by calculating individual subindex for each pollutant
• Subindex is defined as segmented linear function
• Overall API is the MAXIMUM of all the sub-index values
Index
Value
24 hr
TSP
g/m3
24 hr
SO2
g/m3
TSPxSO2
(g/m3)2
8 hr CO
mg/m3
8 hr O3
g/m3
1 hr NO2
g/m3
0
0
0
N/A
0
0
N/A
50
75
80
N/A
5
118
N/A
100
260
365
N/A
10
235
N/A
200
375
800
65,000
17
400
1130
300
625
1600
261,000
34
800
2260
400
875
2100
393,000
46
1000
3000
500
1000
2620
490,000
57.5
1200
3750
HAPs: Mercury
• Elemental Hg inhaled as a vapor,
absorbed by lungs
• Cause: vaporized mercury
• Sources: coal combustion, accidental
spill, mining
• Effects: Nervous system (acute, high),
respiratory system (chronic, low),
kidneys, skin, eyes, immune system;
Mutagenic properties
• Symptoms
– Acute: chills, nausea, chest pains/tightness,
cough, gingivitis, general malaise
– Chronic: weakness, fatigue, weight loss,
tremor, behavioral changes
istockphoto.com
http://www.istockphoto.com/imageindex/728/1/728179/Mercury_drops_Hg.html
HAPs: Dioxins
• Generic term for several
chemicals that are highly
persistent in the environment
– chlorinated dibenzo-p-dioxins (CDDs)
– chlorinated dibenzofurans (CDFs)
– certain polychlorinated biphenyls
(PCBs)
• Cause: burning chlorine-based
compounds with hydrocarbons
• Sources: waste incinerator
2,3,7,8-Tetrachlorodibenzo-p-dioxin
2,3,7,8-Tetrachlorodibenzofuran
3,3',4,4',5,5'-Hexachlorobiphenyl
HAPs: Dioxins
• Varying toxicity
– Generally problems with high
exposures
– Exact effects of low exposures
not really known
• Health Effects
– Carcinogenic
Comparative Photos Showing Yuschenko Immediately Prior
To And Immediately Following Dioxin Poisoning
http://en.wikipedia.org/wiki/Viktor_Yushchenko
(Note: this is an extreme case of dioxin poisoning)
• Some are “known human
carcinogen” (2,3,7,8
tetrachlordibenzo-p-dioxin,
TCDD)
• Others are “reasonably
anticipated to be a Human
Carcinogen”
– Reproductive and
developmental effects
– Chloracne
Other Aerosols: Bioaerosols
• Aerosols with organic origin
– Non-viable: pollen, dander,
insect excreta, sea salt
– Viable: microorganisms
• Cause: aerosolization of
organic material
• Sources:
– Human: sneezing, coughing
– Non-human: wind, waves,
WWTP
• Health Effects: allergies
(pollen) to death
(pathogenic organisms)
Mechanical aeration in
–
idation ditch at UF WWTP
Pathogenic – Minimum
Infectious Dose
Other Aerosols: Bioaerosols
• Allergies
– Pollen, dander, fungi (spores)
• Airborne transmission of
disease
– Bird flu, SARS, Legionnella
(pneumonia)
– Indoor Air Quality
• Ventilation Systems – moist
ductwork, protection, recycled
air
• Office Buildings – Sick Building
Syndrome
– Hospital (nosocomial)
• Biological Warfare
– Anthrax, Ebola virus
Morning Glory Pollen SEM
University of West GA Microscopy Center
http://www.westga.edu/~geosci/wgmc/plants_pics.htm
Other Aerosols: Medicinal
Applications
• Purposely applied medicine
• Take advantage of lung’s portal of
entry (GER – thin membrane of
alveolar)
• Asthma
–Inhaler
• Diabetes
–Pfizer uses Insulin
http://aerosol_beta.ees.ufl.edu/Healthaerosol/section03-2.html
WAYS TO REDUCE AIR POLLUTION
• DRIVE LESS  carpool, walk or ride a bike,
shop by phone or mail, ride public transit,
telecommute.
• DRIVE SMART  obey the speed limit,
combine all errands in one trip, use cruise
control, keep car tuned, don’t top off at the pump,
replace car’s air filter, keep tires properly
inflated, buy clean cars.
• BUY AIR-FRIENDLY PRODUCTS  buy
products that are water-based or are low in
VOCs, buy water-based paints, paint with a brush
instead of a sprayer, use a push or electric lawn
mower, use propane or gas barbecue.
WAYS TO REDUCE AIR POLLUTION
•SAVE ENERGY  turn off lights when you
leave a room, use fluorescent lighting, use a
programmable thermostat, insulate your
home, use a fan instead of an air-conditioner,
install low-flow shower heads.
• WASTE NOT  choose recycled products,
choose products with recycled packaging,
print or xerox on both sides of the paper, reuse
paper bags, recycle papers, plastics and
metals.
• DON’T CREATE DUST  don’t use
fireplace on days with unhealthy air, use rake
instead of leaf blower, drive slowly on dirt
roads.