Human Health and Environmental Effects of the Clear Skies Initiative

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Human Health and Environmental Effects of the Clear Skies Initiative Clear Skies Workshop June 19, 2002 Clear Skies

Presentation Overview The importance of PM 2.5 - a multiple pollutant What s new on health effects and statistics We are moving to implement the new NAAQS Most cost-effective approaches first What we know best This means regional strategies first A clear alternative approach A new regulatory baseline for power generation Overview of expected reductions and air quality benefits

New PM 2.5 AQI Health Messages: A pollutant for all seasons Ozone PM 2.5

What's new in PM science? New PM Criteria Document will include a comprehensive evaluationof hundreds of new health studies Some exceptions, but generally appear to be consistent with studies from previous PM NAAQS review 3rd draft in May 2002, (www.epa.gov/ncea/partmatt.htm), review schedule extended Selected examples of important emerging studies that will be included in this ongoing evaluation of the evidence: HEI's NMMAPS reported association between premature death and PM10 across 90 largest U.S. cities (Samet et al., 2000) Results can t be explained by other pollutants, weather, or statistics Some variability in PM effects estimates with region BUT: very recent findings on statistical problems with the effects estimates (more later) HEI reanalysis of Harvard Six City and American Cancer Society studies confirmed findings of link between long-term PM 2.5 /sulfate exposure and premature mortality from heart and lung diseases (Krewski et al., 2000) Major new Journal of American Medical Association study of ACS data expands and supports previous link between PM 2.5 /sulfate exposure and cardiopulmonary deaths; new evidence of link with lung cancer deaths (Pope et al., 2002) Several new studies have reported links between ambient PM and specific cardiac effects, e.g., risk of heart attacks (Peters et al., 2001)

Potential PM 2.5 Non-Attainment -- Current Data* Concentration (ug/m 3 ) (the new standard is 15ug/m 3 ) 0-10 10-15 15-18 > 18 Nationwide: 173 counties (82 million people) > PM 2.5 NAAQS East: 157 counties (59 million people) >PM 2.5 NAAQS *Based on 1999-2000 incomplete data, 3 years data required for attainment determination

Urban v. Rural (Annual Average Concentrations)

Esther (1995-99) 4.6 ug m -3 Egbert (1994-99) 8.9 ug m -3 Abbotsford (1994-95) 7.8 ug m -3 Toronto (1997-99) 12.3 ug m -3 Sulfate Nitrate Ammonium Black carbon Organic carbon Soil Other St. Andrews (1994-97) 5.3 ug m -3 Fresno (1988-89) 39.2 ug m -3 Quaker City OH (1999) 12.4 ug m -3 Kern Wildlife Refuge (1988-89) 23.3 ug m -3 Arendstville PA (1999) 10.4 ug m -3 Los Angeles (1995-96) 30.3 ug m -3 Colorado Plateau (1996-99) 3.0 ug m -3 Mexico City - Netzahualcoyotl (1997) 55.4 ug m -3 Mexico City - Pedregal (1997) 24.6 ug m -3 Yorkville (1999) 14.7 ug m -3 Washington DC (1996-99) 14.5 ug m -3 Atlanta (1999) 19.2 ug m -3 PM Composition in North America NARSTO

Chemical Composition - Rural Sites IMPROVE/CASTNet Data (1997-1999)

Rural Sulfate Trends track Regional SO x Emissions

Early signs of nitrate substitution in wintertime Chemical Composition - Rural

PM 2.5 and 8-hour Ozone Standards Attainment (current data*) Based on available 1999-2000 PM 2.5 data, 157 counties in the East and 173 counties nationwide are likely to exceed the fine particle standard Currently 82 million people live in 173 counties with projected concentrations greater than 15 ug/m3 (the annual fine particle standard) (59 million in the East) There are currently 333 counties (306 counties in the east) estimated to exceed the 8-hour ozone standard. Currently 120 million people live in 333 counties with projected ozone concentrations greater than 85 ppb (the 8-hour ozone standard) *1997-1999 ozone 1999/2000 PM2.5--preliminary depiction base on two years of data. Three years are required for attainment demonstrations.

PM 2.5 and 8-hour Ozone Standards Attainment (2010) Base Case 2010 The Clear Skies Initiative would result in a substantial number of counties meeting the PM2.5 and 8-hour ozone standards sooner than they would compared to the existing Clean Air Act. Fine particle attainment status in 2010: The Clear Skies Initiative would bring 34 additional counties (home to approximately 10 million people) into attainment with the fine particle standard (as compared to existing programs) Clear Skies 2010 Ozone attainment status in 2010: The Clear Skies Initiative would bring 10 additional counties (home to over 7 million people) into attainment with the 8-hour ozone standard in 2010 (as compared to existing programs)

PM 2.5 and 8-hour Ozone Standards Attainment (2020) Base Case 2020 Fine particle attainment status in 2020: The Clear Skies Initiative would bring 54 counties additional counties (home to approximately 21 million people) into attainment with the fine particle standard (as compared to existing programs) Clear Skies 2020 Ozone attainment status in 2020: The Clear Skies Initiative would bring 8 additional counties (home to over 4 million people) into attainment with the 8-hour ozone standard (as compared to existing programs)

Fine Particle Concentrations (2020) Percent Change 1996 vs. 2020 with Clear Skies Under Clear Skies fine particle concentrations in a large portion of the East and Midwest would improve more than 20% from current levels Clear Skies would reduce fine particle concentrations in the East and Midwest 10-20% beyond what is expected under existing programs Percent Change 2020 Base Case vs. Clear Skies Percent Reduction (A positive percent reduction is a decrease, a negative percent reduction is an increase) Notes: Title IV reduced over 3 million tons of SO 2 between 1990 and 1996 that are not captured by the improvements shown on the map above. Emissions from sources not affected by Title IV or the Clear Skies Initiative, such as mining and metals processing, are expected to increase under the Base Case and Clear Skies.

Deciview Change 1996 vs. 2020 with Clear Skies Deciview Change 2020 Base Case vs. Clear Skies Visibility (2020) Deciview Change Under Clear Skies visibility in a large portion of the East and Midwest would improve 2-3 deciviews from current levels visibility along the southern Appalachian Mountains would improve more than 3 deciviews Clear Skies would improve visibility in the East and Midwest 1-2 deciviews beyond what is expected under existing programs Under Clear Skies the WRAP agreement will be honored and the emissions reductions are expected to take effect allow future growth in the West to occur without degrading visibility (An increase in deciview is an improvement in visibility; a decrease in deciview is a decrease in visibility.)

Acid Rain: Overview Acid deposition is still a regional problem Highest sulfate deposition occurs in the Midwest and northeastern United States, both adjacent to and downwind of the highest emitting areas Impacts occur in both the eastern U.S. and mountainous areas of the West Acidic surface waters in regions surveyed by the National Surface Water Survey Effects of acid deposition include: Acidification of lakes and streams, making them unsuitable for fish and other aquatic life Damage to forests through acidification of soil, depletion of soil nutrients, and direct injury to tree leaves and needles Harm to material and cultural resources, including buildings, statues and monuments Deposition data measured by CASTNet and NADP, 1997-1999

Nitrogen Deposition in Forests and Coastal Waters Nitrogen deposition contributes to nutrient over-enrichment (eutrophication) along eastern and Gulf coasts and to excess nitrogen in sensitive forests. Two thirds of U.S. estuaries (about 84) experience symptoms of moderate to high eutrophication (excessive loadings of nutrients) Excess nitrogen leads to eutrophication of coastal waters Roughly 10-40% of the nitrogen reaching East and Gulf coast estuaries is transported and deposited via the atmosphere Wet Nitrate Deposition to Sensitive Resources High nitrogen deposition levels can lead to loss of soil nutrients and declines in sensitive forest ecosystems Nitrogen saturation occurs when too much nitrogen enters sensitive forest soils and begins to leach out, stripping soil nutrients Deposition data measured by CASTNet and NADP, 1997-1999

Percent Change 1996 vs. 2020 with Clear Skies Sulfur Deposition (2020) Under Clear Skies, sulfur deposition in much of the east would be reduced 30-60% from current levels Clear Skies would reduce sulfur deposition in the east more than 30% beyond what is expected under existing programs Percent Change 2020 Base Case vs. Clear Skies Percent Reduction (A positive percent reduction is a decrease, a negative percent reduction is an increase) Notes: Title IV reduced over 3 million tons of SO 2 between 1990 and 1996 that are not captured by the improvements shown on these maps.

Nitrogen Deposition (2020) Percent Change 1996 vs. 2020 with Clear Skies Percent Change 2020 Base Case vs. Clear Skies Under Clear Skies nitrogen deposition in the Southeast and mid-atlantic will be reduced up to 60% from current levels The large reductions in nitrogen deposition on the West coast occur in the Base Case as well (due to the Tier II and Diesel Rules) Clear Skies would reduce nitrogen deposition in the East 15-30% beyond what is expected under existing programs Percent Reduction Clear Skies would allow growth to occur in the West without increasing NOx emissions (A positive percent reduction is a decrease, a negative percent reduction is an increase)

Acid Status of Lakes in the Adirondacks Lakes in the Adirondack Mountains generally respond relatively rapidly to changes in emissions and deposition ( direct response ), with larger decreases in deposition yielding significant improvement in lake condition Under existing programs, lake conditions improve but 12% of lakes would remain chronically acidic in 2030 With Clear Skies, lake conditions would improve dramatically by 2030: only 3% of lakes would remain chronically acidic % of lakes chronically acidic 25 20 15 10 5 21% Adirondack Lakes 12% 3% However, a significant proportion of Adirondack lakes would still become acidic periodically due to seasonal or storm events 0 current Base (2030) Clear Skies (2030)

Acid Status of Lakes in the Northeast Lakes in the Northeast region (including Adirondack lakes) contain both direct and delayed response systems; some lakes may take longer than 2030 to completely respond to deposition changes considered here Under existing programs, lake condition improves slightly in the Northeast by 2030, but 6% of lakes remain chronically acidic With the Clear Skies Initiative, chronic acidity would be virtually eliminated by 2030 but some lakes would still become acidic periodically due to seasonal or storm events Northeast 12 % of lakes chronically acidic 10 8 6 4 2 0 Current Base (2030) Clear Skies (2030)

Acid Status of Streams in the Southeast Due to the geologic age of the southeastern landscape, streams in the Southeast are predominantly delayed response systems. Under existing programs, stream condition gets worse: 8% more streams become acidic periodically due to seasonal or storm events by 2030 Stream condition continues to get worse beyond 2030; by 2050, the number of chronically acidic streams increases 2% Under Clear Skies the rate of stream acidification would slow: only 6% of streams would become acidic periodically due to seasonal or storm events by 2030 there would be no increase in chronically acidic streams between2030 and 2050 % of streams chronically acidic 18 16 14 12 10 8 6 4 2 0 Southeast 17% 17% 17% Current Base (2030) Clear Skies (2030) These results demonstrate that large reductions in emissions and deposition, such as those under Clear Skies, are necessary simply to slow the long-term decline in stream condition in the Southeast

Regional Health and Visibility Economic Benefits (2010) Total PM-Related Health and Visibility Benefits in 2010 Under the Clear Skies Initiative Northern Midwest ($13 Billion) The Clear Skies Initiative would result in substantial early human health and visibility benefits The total economic benefits of the Clear Skies Initiative would be $44 billion in 20101 North Atlantic ($15 Billion) West ($1 Billion) South Atlantic ($8 Billion) Southern Midwest ($7 Billion) 1The $43 billion in health benefits $1 billion in visibility benefits An alternative estimate would result in health benefits of $5 billion in 2010 two sets of benefits estimates presented here reflect alternative assumptions and analytical approaches regarding quantifying and evaluating the effects of airborne particles on public health. The Base Estimate relies on estimates of the potential cumulative effect of long-term exposure to particles on mortality, while the Alternative Estimate presumes that PM effects on mortality are limited to those that accumulate over much shorter time periods. All such estimates are subject to a number of assumptions and uncertainties. It is of note that, based on recent preliminary findings from the Health Effects Institute, the magnitude of the short-term mortality (alternative estimates) and hospital/er admissions estimates (both estimates) may be overstated. The alternatives also use different approaches to value health effects damages. The key assumptions, uncertainties, and valuation methodologies underlying the approaches used to produce these results are detailed in a benefits analysis technical support document that will accompany the benefits analyses for the Clear Skies proposal.

Regional Health Benefits (2010) Long-Term Change in Mortality Incidence in 2010 Due to Reductions in PM2.5 Under the Clear Skies Initiative Northern Midwest (1900) North Atlantic (2200) West (100) Southern Midwest (1000) 1The South Atlantic (1100) The Clear Skies Initiative would result in substantial early human health and visibility benefits Nationwide the Clear Skies Initiative would annually prevent (by 2010)1: approximately 6,000 premature deaths approximately 4,000 cases of chronic bronchitis An alternative estimate would result in approximately 3,800 premature deaths prevented annually two sets of benefits estimates presented here reflect alternative assumptions and analytical approaches regarding quantifying and evaluating the effects of airborne particles on public health. The Base Estimate relies on estimates of the potential cumulative effect of long-term exposure to particles on mortality, while the Alternative Estimate presumes that PM effects on mortality are limited to those that accumulate over much shorter time periods. All such estimates are subject to a number of assumptions and uncertainties. It is of note that, based on recent preliminary findings from the Health Effects Institute, the magnitude of the short-term mortality (alternative estimates) and hospital/er admissions estimates (both estimates) may be overstated. The alternatives also use different approaches to value health effects damages. The key assumptions, uncertainties, and valuation methodologies underlying the approaches used to produce these results are detailed in a benefits analysis technical support document that will accompany the benefits analyses for the Clear Skies proposal.

Regional Health and Visibility Economic Benefits (2020) Total PM-Related Health and Visibility Benefits in 2020 Under the Clear Skies Initiative Northern Midwest ($27 Billion) North Atlantic ($33 Billion) West ($1 Billion) South Atlantic ($20 Billion) Southern Midwest ($15 Billion) 1The The total economic benefits of the Clear Skies Initiative would be $96 billion in 20201: $93 billion in health benefits $3 billion in visibility benefits An alternative estimate would result in health benefits of $11 billion in 2020 Using either estimate, the benefits significantly outweigh the costs two sets of benefits estimates presented here reflect alternative assumptions and analytical approaches regarding quantifying and evaluating the effects of airborne particles on public health. The Base Estimate relies on estimates of the potential cumulative effect of long-term exposure to particles on mortality, while the Alternative Estimate presumes that PM effects on mortality are limited to those that accumulate over much shorter time periods. All such estimates are subject to a number of assumptions and uncertainties. It is of note that, based on recent preliminary findings from the Health Effects Institute, the magnitude of the short-term mortality (alternative estimates) and hospital/er admissions estimates (both estimates) may be overstated. The alternatives also use different approaches to value health effects damages. The key assumptions, uncertainties, and valuation methodologies underlying the approaches used to produce these results are detailed in a benefits analysis technical support document that will accompany the benefits analyses for the Clear Skies proposal.

Regional Health Benefits (2020) Long-Term Change in Mortality Incidence in 2020 Due to Reductions in PM2.5 Under the Clear Skies Initiative Northern Midwest (3400) North Atlantic (4100) West (100) Southern Midwest (1900) 1The South Atlantic (2500) Nationwide the Clear Skies Initiative would annually prevent (by 2020)1: approximately 12,000 premature deaths over 7,000 cases of chronic bronchitis An alternative estimate would result in approximately 7,000 premature deaths prevented annually by 2020 two sets of benefits estimates presented here reflect alternative assumptions and analytical approaches regarding quantifying and evaluating the effects of airborne particles on public health. The Base Estimate relies on estimates of the potential cumulative effect of long-term exposure to particles on mortality, while the Alternative Estimate presumes that PM effects on mortality are limited to those that accumulate over much shorter time periods. All such estimates are subject to a number of assumptions and uncertainties. It is of note that, based on recent preliminary findings from the Health Effects Institute, the magnitude of the short-term mortality (alternative estimates) and hospital/er admissions estimates (both estimates) may be overstated. The alternatives also use different approaches to value health effects damages. The key assumptions, uncertainties, and valuation methodologies underlying the approaches used to produce these results are detailed in a benefits analysis technical support document that will accompany the benefits analyses for the Clear Skies proposal.

Human Health Benefits of Reducing Fine Particulate Matter: Non-Mortality Benefits 1 Clear Skies would result in significant early benefits in 2010: 3,900 avoided cases of chronic bronchitis 5,600 fewer hospitalizations/emergency room visits for cardiovascular and respiratory conditions 7.2 million fewer days with respiratory illnesses and symptoms, including work loss days, restricted activity days, and says with asthma attacks By 2020, Clear Skies would prevent: 7,400 cases of chronic bronchitis 10,500 hospitalizations/emergency room visits for cardiovascularand respiratory conditions 13.5 million days with respiratory illnesses and symptoms, including work loss days, restricted activity days, and days with asthma attacks 1 Based on recent preliminary findings from the Health Effects Institute, the magnitude of the short-term mortality (alternative estimates) and hospital/er admissions estimates (both estimates) may be overstated. The keyassumptions, uncertainties, and valuation methodologies underlying the approaches used to produce these results are detailed in a benefits analysis technical support document that will accompany the benefits analyses for the Clear Skies Initiative.