Presentation Transcript
The Impact of Changes in Transportation and Commuting Behaviors During The 1996 Summer Olympic Games in Atlanta on Air quality and Childhood Asthma: The Impact of Changes in Transportation and Commuting Behaviors During The 1996 Summer Olympic Games in Atlanta on Air quality and Childhood Asthma Michael Friedman, M.D.
Air Pollution and Respiratory Health Branch
National Center for Environmental Health
Centers for Disease Control and Prevention (CDC)
Presented/abridged by Leanne West
Georgia Tech Research Institute
Health Effects of Air Pollution: An Overview of Scientific Evidence to Date: Health Effects of Air Pollution: An Overview of Scientific Evidence to Date Strong Evidence of Pollution Exposure linked to:
Excess Mortality in elderly
(most heart and lung related deaths)
Hospital admissions for heart and lung problems
Asthma exacerbations
Bronchitis symptoms
Health Effects of Air Pollution: The Role of Individual Pollutants: Health Effects of Air Pollution: The Role of Individual Pollutants PM10 Elderly and infant mortality, asthma flares
hospitalization for heart/lung problems
PM2.5 Elderly mortality, asthma flares, ??
Ozone (O3) asthma and bronchitis symptoms, CHD?, ??
Carbon Monoxide (CO) Heart attacks ?, CHD ?
Sulfur Dioxide (SO2) Bronchitis, cough symptoms
Nitrogen Oxides (NOx) Breathing problems, lung function decrease
VOCs (i.e., benzene) childhood leukemia ?
Heavy Metal Oxides ??
Mixture of Pollutants asthma flares, ??
Link Between Air Quality and Asthma: Link Between Air Quality and Asthma Epidemiological Time Series Studies:
Association between high ozone and/or particulate levels (PM10) and acute asthma exacerbations (or changes in daily asthma symptom scores or PFTs)
Laboratory Studies
Using human lung washings/cells or animal models
Experimental Studies
Expose volunteers to various concentrations of pollutants and measure lung function changes
Air Quality and Asthma:Unanswered Questions: Air Quality and Asthma: Unanswered Questions No study to date had examined the impact of improved city-wide automobile congestion on asthma rates
Need for alternatives to time-series methodology
study cumulative effect over time
measure potential synergy of exposure to multiple pollutants
de-couple pollutant levels and weather change
specifically examine impact of emission-lowering interventions
The 1996 Summer Olympic Games in Atlanta provided such an opportunity
Preparations in Atlanta for The 1996 Summer Olympic Games: Preparations in Atlanta for The 1996 Summer Olympic Games “All eyes to be on Atlanta”
1 million plus visitors ….
severe traffic congestion….
problems getting to Olympic venues
Plan developed to alleviate traffic worries
Atlanta’s Plan to Control Automobile Traffic Congestion during the 1996 Summer Olympic Games: Atlanta’s Plan to Control Automobile Traffic Congestion during the 1996 Summer Olympic Games Expand and encourage use of public transportation
24-hour a day bus and rail service
1000 additional buses for park-and-ride services
free use for Olympic event ticket holders
Promote alternative commuting practices that emphasize shifting travel demand out of the rush hour periods
i.e., telecommuting, flextime, staggered work hours, altered delivery and pick-up schedules, carpooling
Atlanta’s Plan to Control Automobile Traffic Congestion during the 1996 Summer Olympic Games: Atlanta’s Plan to Control Automobile Traffic Congestion during the 1996 Summer Olympic Games Media warnings of potentially-severe traffic congestion
Highway improvements
road widenings
creation of high-occupancy lanes
Traffic restrictions within Olympic ring/downtown area
Our Basic Study Questions: Our Basic Study Questions Did Atlanta’s traffic strategy really work?
What impact did this have on air quality?
What impact did this have on asthma exacerbation rates?
The Olympic Asthma Study: Methods: The Olympic Asthma Study: Methods Ecological study design
comparing the 17 days of the Olympics to the 4 weeks before/after (baseline)
Data Collection:
Acute care visits for asthma* (first ICD9 = 493)
All non-asthma acute care visits*
Levels of individual air pollutants
Meteorological conditions
Vehicular traffic counts
Monthly gasoline sales via statewide gas tax records
Public transportation usage
*note: study population included all 1-16 year old residents of the 5 most central counties of Atlanta
Results: Acute Care Visits for Asthma1-16 year old residents of Atlanta: Results: Acute Care Visits for Asthma 1-16 year old residents of Atlanta Mean Daily Number of Events * p = 0.01
Results: Total Non-Asthma Related Acute Care Visits1-16 year old residents of Atlanta: Results: Total Non-Asthma Related Acute Care Visits 1-16 year old residents of Atlanta Mean Daily Number of Events
Mean levels of major pollutants before, during, and after the Olympic Games as a percentage of the EPA’s National Ambient Air Quality Standard (NAAQS) for that pollutant1: Mean levels of major pollutants before, during, and after the Olympic Games as a percentage of the EPA’s National Ambient Air Quality Standard (NAAQS) for that pollutant1 Pre-Olympics (baseline period) Olympic Period Post-Olympics (baseline period) 1NAAQS at time of study: ozone = 120 ppb; particulate matter < 10um (PM10) = 150 ug/m3; carbon monoxide (CO) = 9 ppm; nitrogen dioxide (NO2) = 600 ppb; sulfur dioxide (SO2) = 140 ppb 0 10 20 30 40 50 60 70 80 Ozone PM10 CO NO2 SO2 % of EPA Air Quality Standard
The relationship between acute asthma events and ozone concentrations averaged over the 3 days preceding the event: The relationship between acute asthma events and ozone concentrations averaged over the 3 days preceding the event * p < 0.01 Average Number of Asthma Visits Per Day
Results: Morning Rush-hour Traffic Countsdaily average for all roads: Results: Morning Rush-hour Traffic Counts daily average for all roads * p < 0.0001 for all 4 roads
Results: 24-hour Total Traffic Countsdaily average for all 4 roads combined: Results: 24-hour Total Traffic Counts daily average for all 4 roads combined * p < 0.05 for 2 of the 4 roads
Results: Morning Rush Hour and Ozone Formation: Results: Morning Rush Hour and Ozone Formation Dangerously High Peak Ozone Levels
almost always between 12-4 PM Rapid Increase in Ozone Formation
especially in early afternoon
when temperature and sunlight
is at maximal intensity Build Up of Ozone Precursors
in Atmosphere by late morning Stop-and-Go Traffic Jams High Morning Rush Hour Traffic Volumes
Mean Daytime Meteorological Measures During The Olympics Relative To The Baseline Period: Mean Daytime Meteorological Measures During The Olympics Relative To The Baseline Period
Other Evidence Favoring Traffic Changes as the Cause of Improved Air Quality: Other Evidence Favoring Traffic Changes as the Cause of Improved Air Quality Ozone concentrations decreased more in Atlanta than 3 other Georgia sites with similar weather patterns (28% vs. 11%, 17%, 18%)
Carbon Monoxide concentrations decreased 18% during the Olympics
levels much more dependent on automobile emissions than weather
Sulfur Dioxide concentrations increased 22%
consistent with increased use of diesel powered buses and generators
should not have increased if weather conditions favored good air quality
Positive correlation between weekday morning rush hour traffic counts and that day’s peak ozone concentration
( r using roads 1 - 4 = + 0.29, 0.42, 0.34, 0.39 respectively)
Olympic Asthma Study: Conclusions: Olympic Asthma Study: Conclusions Measurable short-term changes in transportation and commuting occurred, leading to improved air quality, and fewer asthma exacerbations in Atlanta’s children
Limitations of study: Retrospective nature of the study
Lack of critical data
No modeling, only correlations
Implications: innovative urban transportation and commuting strategies aimed at decreasing peak hour automobile use and increasing traffic flow may substantially improve the respiratory health of its citizens
The Next Step: Reasking the 3 Basic Study Questions: The Next Step: Reasking the 3 Basic Study Questions Can traffic reduction and/or emission reduction strategies work, and if so, how?
What impact will this have on air quality?
What impact will this have on health?
i.e., asthma development or exacerbations, death rates among the very young and old, etc.
Acknowledgements: Acknowledgements Rafael Balagas Georgia Environmental Protection Division
Bill Murphy
Darren Palmer U.S. Environmental Protection Agency
Dennis Tolsma Kaiser-Permanente
Deborah Griffin
Gene McDowell Scottish-Rite Medical Center
W. Gerald Teague Egleston Children’s Hospital
Phil Harris Georgia Department of Medical Assistance
Dale Shuirman Georgia Department of Revenue
Chris Porter Cambridge Systematics
The Georgia Department of Transportation
The Atlanta Allergy and Asthma Clinic
Metropolitan Atlanta Rapid Transit Authority (MARTA)