Health Effects of Fine Particles. Bart Ostro, Ph.D., OEHHA Cal EPA

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1 Health Effects of Fine Particles Bart Ostro, Ph.D., OEHHA Cal EPA

2 PM10 and PM2.5: Size and Composition Fine Coarse Ultra Fine Sulfates Nitrates Ammonia Carbon Lead (HM) Organics Soil Dust Silica Salts Pollen Tire Rubber 0.1 µm 1 µm 2.5 µm 10 µm

3 HOW SMALL IS PM2.5? Hair cross section (60 µm) Human Hair (60 µm diameter) PM10 (10 µm) PM2.5 (2.5 µm)

4 Existing Epidemiologic Studies These studies examine association between real-world exposures and health outcomes Include a wide range of conditions (different age groups, health status, climates, co-pollutants). Monitoring of PM2.5 is relatively new -- far fewer studies versus PM10.

5 Recent Findings Regarding PM Short-term (daily) exposure to PM2.5 and daily counts of mortality (time-series studies) 2. Short-term exposure to PM2.5 and heart attacks, arrhythmias, heart rate variability, hospital admissions, asthma, respiratory symptoms, lung function

6 Recent Findings Regarding PM Traffic exposure during pregnancy may be related to low birth weight, pre-term births and birth defects and to bronchitis and asthma in exposed children 4. Long-term exposure to PM2.5 and mortality and life expectancy

7 Long-term exposure to PM2.5 Several studies report associations between mortality and long-term exposure to PM2.5. The largest involves the American Cancer Society (ACS) cohort of roughly 550,000 individuals in 151 cities, 8 years of follow-up. Analysis accounts for many other individuallevel mortality risk factors (e.g., smoking, weight, alcohol, occupational exposure, gender, age, diet and others).

8 Long-term exposure to PM2.5 Reanalysis funded by Health Effects Institute: confirmed findings and conducted additional analysis without change in results (Krewski et al., 2000) Recent study (Pope et al., 2002) used ACS cohort and 16 years of follow-up. Reported association between PM2.5 and mortality from both lung cancer and cardiopulmonary disease.

9 Long-term exposure to PM2.5 Specifically, these findings suggest that a 10 µg/m 3 change in PM2.5 is associated with a: 9% increase in mortality from heart/lung disease 14% increase in mortality from lung cancer The loss of life for each case is estimated to be 8 years.

10 What are the Implications of These Studies? WHO report on Global Burden of Disease suggests between 800,000 and 1.1 million deaths per year from heart/lung disease attributed to air pollution (2-3% of worldwide cardiopulmonary mortality) State of California study indicates 6,500 deaths per year averted if PM2.5 standard is attained. What about the U.S.?

11 Which of the Following Causes the Most Death in the U.S., in 2001? a) Homicides b) Alcohol c) Fine Particles d) Drugs e) Suicides f) Flu and pneumonia g) Malaria h) Motor vehicle accidents

12 Which of the Following Causes the Most Death in the U.S., in 2001? a) Homicides: 20,000 b) Alcohol: 19,800 c) Fine Particles: 64,000 (est.) d) Drugs: 21,700 e) Suicides: 30,600 f) Flu and pneumonia: 62,000 g) Malaria: 9 h) Motor Vehicles: 43,800 Source: CDC. National Vital Statistics Reports, 2003: U.S.EPA, NRDC

13 Mortality Estimates for PM2.5 NRDC: Difference between 1996 concentrations and 12 µg/m 3 standard = 41,000 9 µg/m 3 = 64,000. U.S. EPA: Section 812: Difference between Preand Post-CAA in year 2000 = ~200,000. OMB: Four air programs reducing PM (SO2 control, light duty engines and 2 on heavy duty engines) = ~ $110B in benefits and ~ $9B in costs per year.

14 PM-related Premature Mortality Estimates PM2.5 Concentration Pre-CAA Concentrations 184, ,000 41,000 Post-1970 CAA and 1990 CAAA Conc

15 These Recent Studies Have Implications for Ambient Air Quality Standards Annual Average 24-hour Average California, new U.S. current U.S. proposed

16 Unresolved Issues with PM 1. What subfraction (size/composition) is most important in health effects? 2. Do early-life exposures have a life-long impact? 3. What are the underlying mechanisms for the health impacts? 4. Are there other sensitive subgroups (by age, economic status, race/ethnicity)? 5. What are the effects of proximity to roadways?

17 Visibility < 15 km Visibility > 100 km

18 The citation for the estimates are: US Environmental Protection Agency,1997. The Benefits and Costs of the Clean Air Act, 1970 to Prepared for US Congress by US EPA, Office of Air and Radiation/Office of Policy Analysis and Review, Washington, DC, p. D-45 and US Environmental Protection Agency, The Benefits and Costs of the Clean Air Act, Prepared for US Congress by US EPA, Office of Air and Radiation/Office of Policy Analysis and Review, Washington, DC, November; EPA report no. EPA-410-R , p. D-87 - D-88.