Why Georgia Needs Gooder: Health Effects of O3 and PM2.5 Stefanie E. Sarnat, Sc.D. Emory University Georgia Air Quality and Climate Summit Atlanta, GA, May 7th, 2008

Background U.S. EPA recently revised NAAQS standards O3 standard: Including “primary” standards – designed to protect human health O3 standard: Revised March 12, 2008 0.08 ppm 8-hour standard lowered to 0.075 ppm http://www.epa.gov/groundlevelozone/pdfs/2008_03_factsheet.pdf PM2.5 standard: Revised September 21, 2006 65 µg/m3 24-hour standard lowered to 35 µg/m3 15 µg/m3 annual standard retained http://www.epa.gov/particles/pdfs/20060921_factsheet.pdf Revisions were made to short-term standards Should protect against acute O3- and PM2.5-related health effects

Respiratory System Morphology Naso-oro Alveolar Tracheal Bronchial, Bronchiolar

Mechanisms of Ozone Toxicity Common denominator of all ozone-related health effects: Inflammatory response mechanism Ozone inhaled… Not likely to penetrate deeper than epithelial lining fluid May react with cellular components E.g., polyunsaturated fatty acids, amino acids, and low-molecular-weight compounds (glutathione, urate, vitamins C and E) Linked to release of pro-inflammatory mediators Thickening of air-blood barrier Impeded oxygen diffusion to blood U.S. EPA, O3 Air Quality Criteria Document, 2006

Example of Lung Tissue Damage Upper slide = exposure to filtered air Cilia clear lungs of mucus Cilia appear in neat and regular rows Lower slide = exposure to 200 ppb of O3 for four hours while exercising Missing, misshapen cilia Neutrophil release (arrows) indicates inflammation Figure 1. Microscopic views of human lung tissue (epithelium, or lining) show damage resulting from exposure to relatively low levels of ozone. In the control image (upper) from the lung of a person exposed only to air, the tiny cilia that clear the lungs of mucus appear along the top of the image in a neat and regular row. In the lung exposed to 0.20 ppm of ozone added to the air for four hours during moderate exercise, many cilia appear missing and others appear misshapen. Arrows point to tiny bodies called neutrophils in the ozone-exposed subject. The presence of neutrophils indicates inflammation. Magnification: x400. (American Review of Respiratory Diseases, Vol. 148, 1993, Robert Aris et al., pp. 1363-1372.) Aris et al. American Review of Respiratory Diseases, 1993

Mechanisms of PM Toxicity Pope and Dockery. Journal of the Air and Waste Management Association, 2006

Health Impacts of O3 and PM2.5 Premature death in people with heart and lung disease Increased hospital visits for respiratory diseases (and for CVD for PM2.5) Reduced lung function Increased symptoms (coughing, wheezing) Aggravation of chronic lung diseases Increased susceptibility to respiratory infection (O3) Heart rate variability, arrhythmias (PM2.5) Severity Proportion of Population Affected U.S. EPA, http://www.epa.gov/groundlevelozone/pdfs/2008_03_factsheet.pdf, 2008

Study of Particles & Health in Atlanta SOPHIA Study of Particles and Health in Atlanta

SOPHIA - Ambient O3 & ED Visits Exposure: Daily 8-hr max O3 8-hr standard Outcome: Daily respiratory ED visits

SOPHIA - Ambient O3 & ED Visits IQR=29.75 ppb Unpublished SOPHIA results using 1993-2004 data

SOPHIA - Multi-Pollutant Modeling Modified figure from Tolbert et al. Journal of Exposure Science and Environmental Epidemiology, 2007

Health Benefits of Reduced Standards* Reduced cases of… O3^ PM2.5 Premature death ~260 to 2,300 1,200 to 13,000 in people with heart or lung disease Chronic bronchitis 380 2,600 Nonfatal heart attacks 890 5,000 Hospital admissions & emergency department visits 1,900 1,630 CV and resp HAs 1,200 asthma ED visits Acute bronchitis 1,000 7,300 Upper and lower respiratory symptoms 11,600 97,000 Aggravated asthma 6,100 51,000 Missed work or school days 243,000 350,000 Restricted activity days 750,000 2 million *By year 2020, according to EPA Regulatory Impact Analyses; summaries found at http://www.epa.gov/groundlevelozone/pdfs/2008_03_factsheet.pdf http://www.epa.gov/particles/fs20061006.html ^Reflect both O3 and PM pollution reductions resulting from revised O3 standard