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Health Effects of Air Pollution. Wednesday, February 6, 2006 ENV 4101/5105 Godish Chapter 5 and Online Respiratory Health Module (http://aerosol.ees.ufl.edu/default.htm) For extra reference: EPA http://www.epa.gov/air/urbanair/. Introduction. Methods of Exposure Criteria Air Pollutants:
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Health Effects of Air Pollution Wednesday, February 6, 2006 ENV 4101/5105 Godish Chapter 5 and Online Respiratory Health Module(http://aerosol.ees.ufl.edu/default.htm) For extra reference: EPA http://www.epa.gov/air/urbanair/
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 Question: Why doesn’t the pulmonary-alveolar region have more natural protection mechanisms? 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:
Criteria Air Pollutants: Particulate Matter • Two possible fates • Factors affecting fate • Aerodynamic properties • Physiological behavior • Methods of Deposition • Impaction* • Interception* • Diffusion* • Electrostatic Attraction • Gravitational Settling Which mechanisms will work better for large particles? For small particles? Adapted from Universite Laval http://www.theses.ulaval.ca/ 2004/21789/ch01.html
Major contributors Impaction Predominant for dp 3 m PM2.5 regulations Primarily in HAR or TBR Visual example: http://aerosol.ees.ufl.edu/respiratory/section04-1.html Brownian diffusion Predominant for dp 0.5 m Visual example: http://aerosol.ees.ufl.edu/respiratory/section04-3.html Gravitational Settling 3-5 m (VTS dar2) Distal/horizontal regions of bronchial airways Visual example: http://aerosol.ees.ufl.edu/respiratory/section04-2.html Minimal effect Electrostatic Attraction Interception Elongate particles Visual example: http://aerosol.ees.ufl.edu/respiratory/section04-4.html Criteria Air Pollutants: Particulate Matter
Criteria Air Pollutants: Particulate Matter dp<0.1 0.1<dp<1 DF=Total DFHA=Head Airways DFTB=Tracheobronchial DFAL=Alveolar region dp>PM2.5 • Why is there a dip in deposition fraction between 0.1 and 1 m? • 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 • 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) Wide Range
Criteria Air Pollutants: Particulate Matter • PM10 (<10 m, coarse (2.5-10 m) and fine particles) • Anything larger deposited in the HAR (nasal-pharangycal) • 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)
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? • Treatment: fresh air, oxygen therapy, hyperbaric chamber Parrish Medical Center http://www.parrishmed.com/programs_ services/wound_hyperbaric.cfm
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 • Why do we use ozone as disinfectant for WW? • 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_management/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)
Criteria Air Pollutants: Air Quality Index (AQI) • Begin by calculating individual subindex for each pollutant • Subindex is defined as segmented linear function • What is the index value if 8-hr CO is 9 mg/m^3? • Overall API is the MAXIMUM of all the sub-index values
Criteria Air Pollutants: Air Quality Index (AQI) • Group Work: Calculate the PSI and give a verbal description of air that contains 7 mg/m3 CO (8-hour average), 300 g/m3 TSP (24-hour average), and 300 g/m3 SO2 (24-hour average)? • Reminder: Good (0-50); Moderate (51-100); Unhealthful (100-199); Very Unhealthful (200-299); Hazardous (>300) http://www.dep.state.fl.us/air/flaqs/forecast.htm
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 • 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 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)
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) • Pathogenic – Minimum Infectious Dose Mechanical aeration in oxidation ditch at UF WWTP
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
Respiratory System and methods of deposition _____________________ _____________________ _____________________ Particulate Matter _____________________ Carbon Monoxide _____________________ Ozone _____________________ NOx _____________________ SOx _____________________ Lead _____________________ HAPs Mercury _______________________ Dioxins _______________________ Bioaerosols _____________________ Review of Lecture