Combined National and State-level Health 

Benefits for the Cross-State Air Pollution Rule 

and Mercury and Air Toxics Standards
EPA-452/R-11-014

December 2011

Combined National and State-level Health Benefits for the Cross-State Air Pollution Rule and 

Mercury and Air Toxics Standards 

By: 

Office of Air and Radiation

U.S. Environmental Protection Agency

Washington, District of Columbia

and

Office of Air Quality Planning and Standards 

U.S. Environmental Protection Agency

Research Triangle Park, North Carolina

U.S. Environmental Protection Agency

Office of Air Quality Planning and Standards

Health and Environmental Impacts Division

Research Triangle Park, North Carolina
The regulatory assessments of the CSAPR and MATS differed in several respects. For 

example, benefits for the CSAPR were estimated directly from air quality modeling of 

anticipated emission reductions for the final rule while MATS benefits were estimated using 

benefit per-ton (BPT) factors derived from a modeled interim policy scenario. The assessments 

also differed in endpoints analyzed. Due to time and resource constraints, the CSAPR 

assessment quantified only the health benefits of PM2.5 and ground-level ozone reductions as 

well as the welfare benefits of recreational visibility improvements and climate benefits of 

carbon dioxide (CO2) reductions while the MATS analysis quantified only the health benefits of 

PM2.5 reductions and the climate benefits of CO2 reductions. Additionally, the emission 

reductions and health benefits were assessed for differing analysis years—2014 and 2016 for the 

CSAPR and MATS, respectively. For more detailed information about the human health and 

welfare benefits of each rule, as well as the inherent limitations and uncertainties in estimating 

these benefits, please refer to their respective Regulatory Impact Analyses (RIAs).

Introduction and Purpose of Analysis

This year EPA finalized two rulemakings requiring reductions of air pollutants from 

electric generators (EGUs)—the Cross-State Air Pollution Rule (CSAPR) and Mercury and Air 

Toxics Standards (MATS). Starting in 2012, the CSAPR requires 28 states in the eastern half of 

the United States to substantially improve air quality by reducing power plant emissions of sulfur 

dioxide (SO2) and nitrogen oxides (NOX) that cross state lines and contribute to fine particle 

pollution (PM2.5) and ground-level ozone (O3) in other states. MATS reduces emissions of toxic 

air pollutants including mercury (Hg), arsenic, chromium, and nickel as well as acid gases 

including hydrogen chloride (HCl) and hydrogen fluoride (HF) from new and existing coal- and 

oil-fired power plants across the U.S. starting as early as 2015. As a co-benefit, MATS also 

reduces SO2 and direct PM2.5 emissions and thereby reduces ambient PM2.5 concentrations.

While these rules have separate and distinct goals, cover different geographic areas, and 

have different implementation timeframes, they are also similar in multiple respects: they affect 

overlapping sets of electricity producers; they were finalized within six months of each other; 

they will each substantially reduce exposure to air pollution and thereby improve human health 

and welfare; and a majority of the quantified benefits of each rule is attributable to reductions in 

PM2.5 resulting from SO2 emission reductions. Given the similarities between these rules, EPA 

estimated the national and state-level benefits of these rules combined, which will provide better 

understanding of their cumulative human health benefits. 

1,2

 1 U.S. Environmental Protection Agency (U.S. EPA). 2011. Regulatory Impact Analysis (RIA) for the 

final Transport Rule. Office of Air and Radiation, Washington, DC. June. Available on the Internet at 

<http://www.epa.gov/airtransport/pdfs/FinalRIA.pdf>.

2 U.S. Environmental Protection Agency (U.S. EPA). 2011. Regulatory Impact Analysis (RIA) for the 

final Mercury and Air Toxics Standard (MATS). June. Available on the Internet at 

<http://www.epa.gov/ttn/ecas/ria.html>.
In order to sum the benefits of the CSAPR and MATS, EPA needed to update the 

CSAPR benefits to reflect the same assessment year as MATS. This required re-running the 

benefits model (Benefits Mapping and Analysis Program (BenMAP

Methods

3

)) to assess PM2.5 and ozone 

benefits for a 2016 assessment year. EPA did not update the visibility benefits or climate benefits 

for the CSAPR. 

Updating the benefits modeling affected two key parameters: population year and 

projected income growth. These key inputs are important to the health impacts assessment 

because the incidence of health impacts reduced, via reduced exposure to air pollutants, depend 

on population exposure and because the valuation of health impacts avoided is sensitive to 

income. Because EPA applies baseline incidence rates for premature mortality in 5 year 

increments (2010, 2015, 2020, etc.), evaluating 2016 rather than 2014 does not change in 

baseline incidence rates used to estimate incidences of premature mortality avoided.

While the purpose of this assessment is to evaluate benefits of the CSAPR in 2016, this 

analysis is based on existing air quality modeling of emissions under the CSAPR in 2014. We 

do not have emissions or air quality modeling to use as the basis for updating the air quality 

information in the benefits modeling. However, EPA does not think that this is a significant 

source of uncertainty because the state-level emission budgets for the CSAPR do not change 

after 2014. While banking of allowances in 2012 and 2013 may impact the trend of emission 

reductions over time, creating the potential for reductions in 2016 to be somewhat different than 

2014, we expect EGU emission reductions in 2016 will likely be generally similar in aggregate 

level and geographic distribution to 2014.

• This assessment accounts for PM2.5-related human health benefits for the CSAPR and MATS 

and ozone-related health benefits for the CSAPR. Time and data limitations precluded the 

inclusion of additional benefits that were quantified in the regulatory assessments of these 

rules such as visibility improvements and greenhouse gas reductions. For a full list of human 

health and welfare effects of pollutants affected by these rules, please refer to Table 5-2 in 

the CSAPR RIA

Limitations

This analysis is a screening-level assessment of the combined benefits of the CSAPR and 

MATS and is limited in its inputs, methods, and results, which are fully described in the 

underlying RIAs. These limitations include: 

1 and Table 5-2 in the MATS RIA.2

• This analysis presents results at the state-level. We are confident, with respect to the 

availability of necessary data at the state-level, in the estimation of state-level mortality 

benefits. Due to the high proportion of total benefits attributable to the reduction in 

premature mortality, we are confident in the total monetized benefits at the state-level. 

 3 Abt Associates, Inc. 2010. Environmental Benefits and Mapping Program (Version 4.0). Bethesda, MD. 

Prepared for U.S. Environmental Protection Agency Office of Air Quality Planning and Standards. 

Research Triangle Park, NC. Available on the Internet at <http://www.epa.gov/air/benmap>.
However, we are less confident in the estimation of morbidity benefits because the

assessment relies on national average baseline incidence rates. Additionally, we are more 

confident in the state-level results for the CSAPR than MATS because, as described in the 

MATS RIA, we did not perform air quality modeling for the final MATS scenario. 

• As mentioned above, we used the available 2014 emissions and air quality modeling for the 

CSAPR to update the benefits of the CSAPR for 2016. While we do not anticipate that this 

is a significant source of uncertainty, we note that emission reductions in 2016 may be 

different than 2014.

• The PM2.5-related benefits for MATS were derived through a BPT approach, which does not 

fully reflect local variability in population density, meteorology, exposure, baseline health 

incidence rates, or other local factors that might lead to an over-estimate or under-estimate of 

the actual co-benefits of reducing ambient PM2.5. 

• State-level results for MATS assume that the state distribution of health co-benefits for the

final policy is equivalent to that of the modeled interim scenario.

• This assessment relies on different methods for estimating the benefits of the CSAPR (air 

quality modeling) and MATS (BPT). We used the BPT method to estimate MATS benefits 

because EPA did not develop air quality modeling for the final rule. Due to the use of the 

benefit per-ton method, there is more uncertainty with the state-level MATS results than for 

the CSAPR, and the added uncertainty in MATS contributes to the summed uncertainty. 

However, EPA does not anticipate that utilizing different methods will result in significant 

uncertainty in the summed benefits. 

• We assume that all fine particles, regardless of their chemical composition, are equally potent 

in causing premature mortality. This is an important assumption because the health benefits 

of these rules are primarily related to reductions of SO2, a precursor to ambient PM2.5. PM2.5

improvements produced via reductions in transported precursors (SO2 and NOX) emitted 

from EGUs may differ significantly from direct PM2.5 released from diesel engines and other 

industrial sources, but the scientific evidence is not yet sufficient to allow differential effects 

estimates by particle type. 

• We assume that the health impact function for fine particles is linear within the range of 

ambient concentrations under consideration. Thus, the estimates include health co-benefits 

from reducing fine particles in areas with varied concentrations of PM2.5, including both 

regions that are in attainment with the fine particle standard and those that do not meet the 

standard, down to the lowest modeled concentrations.

The results of this assessment show a very small increase in total health benefits 

estimated for the CSAPR in 2016 compared to 2014. This increase is due to population growth 

between 2014 and 2016 as well as increases in projected income. After re-calculating the 

CSAPR PM2.5- and ozone-related benefits to reflect population and income growth for 2016, we 

summed these results with the 2016 MATS PM2.5-related benefits to show the combined benefits 

of these two rules. Table 1 below depicts the total quantified and monetized human health 

benefits of the CSAPR and MATS as well as their combined benefits. Table 2 below presents 

the estimated health impacts avoided due to CSAPR and MATS in 2016 at a national level. 

Table 3 below displays the estimated health impacts avoided due to the CSAPR and MATS in 

Results
2016 at the state-level (3% discount rate). This table includes incidences of premature mortality 

avoided and the total value of all quantified and monetized mortality and morbidity benefits. 

The range shows estimated PM2.5-related benefits using Pope et al. (2002)4 and Laden et al. 

(2006)5 as well as ozone-related benefits using Bell et al. (2004)6 and Levy et al. (2005).

7

Table 1: Total monetized human health-related benefits of CSAPR (2014 and 2016) and 

MATS (2007$, billions)

The 

state-level MATS results are reported in Appendix 5D of the MATS RIA.

CSAPR 

2014

CSAPR 

2016

MATS 

2016

CSAPR & MATS 

2016

Pope et al. (2002) & Bell et al. (2004)

3% discount rate $110 $120 $36 $150

7% discount rate $100 $110 $32 $140

Laden et al. (2006) & Levy et al. (2005)

3% discount rate $270 $290 $89 $380

7% discount rate $250 $260 $80 $340

 4 Pope, C.A., III, R.T. Burnett, M.J. Thun, E.E. Calle, D. Krewski, K. Ito, and G.D. Thurston. 2002. Lung 

Cancer, Cardiopulmonary Mortality, and Long-term Exposure to Fine Particulate Air Pollution. Journal of 

the American Medical Association 287:1132-1141.

5 Laden, F., J. Schwartz, F.E. Speizer, and D.W. Dockery. 2006. Reduction in Fine Particulate Air 

Pollution and Mortality. American Journal of Respiratory and Critical Care Medicine 173:667-672.

6 Bell, M.L., et al. 2004. Ozone and short-term mortality in 95 US urban communities, 1987-

2000. Journal of the American Medical Association. 292(19): p. 2372-8.

7 Levy, J.I., S.M. Chemerynski, and J.A. Sarnat. 2005. Ozone exposure and mortality: an 

empiric bayes metaregression analysis. Epidemiology. 16(4): p. 458-68
Table 2: Estimated health impacts avoided due to the CSAPR and MATS—incidences of avoided 

health effects1 and value1 (millions of dollars, 2007$) of mortality and morbidity impacts 

CSAPR 2014 CSAPR 2016 MATS 2016

Health Effect Incidences Value Incidences Value Incidences Value

PM-related endpoints Premature Mortality

Pope et al. (2002) (age > 30) 13,000 14,000 4,200

3% discount rate $100 $110 $34 

7% discount rate $94 $99 $30 

Laden at al. (2006) (age > 25) 34,000 35,000 11,000

3% discount rate $270 $280 $87 

7% discount rate $240 $250 $78 

Infant (< 1 year) 59 $0.52 60 $0.53 20 $0.20 

Morbidity

Chronic Bronchitis 8,700 $4.2 8,900 $4.3 2,800 $1.40 

Non-fatal heart attacks (age > 18) 15,000 16,000 4,700

3% discount rate $1.7 $1.8 $0.50 

7% discount rate $1.3 $1.4 $0.40 

Hospital admissions—respiratory (all ages) 2,700 $0.039 2,800 $0.041 830 $0.01 

Hospital admissions—cardiovascular (age > 18) 5,800 $0.091 6,000 $0.094 1,800 $0.03 

Emergency room visits for asthma (age < 18) 9,800 <$0.01 10,000 <$0.01 3,100 <$0.01

Acute bronchitis (age 8 - 12) 19,000 <$0.01 19,000 <$0.01 6,300 <$0.01

Lower respiratory symptoms (age 7 - 14) 240,000 <$0.01 250,000 <$0.01 80,000 <$0.01

Upper respiratory symptoms (asthmatics age 9 - 18) 180,000 <$0.01 190,000 <$0.01 60,000 <$0.01

Asthma Exacerbation (asthmatics age 6 - 18) 400,000 $0.022 410,000 $0.022 130,000 <$0.01

Lost work days (ages 18 - 65) 1,700,000 $0.21 1,700,000 $0.21 540,000 $0.10 

Minor restricted-activity days (ages 18 - 65) 10,000,000 $0.64 10,000,000 $0.65 3,200,000 $0.20 

Ozone-related endpoints Premature Mortality

Multi-city and NMMAPS

Bell et al. (2004) (all ages) 27 $230 28 $240 - -

Schwartz et al. (2005) (all ages) 41 $360 42 $370 - -

Huang et al. (2005) (all ages) 37 $330 40 $360 - -

Meta-analyses

Ito et al. (2005) (all ages) 120 $1,000 120 $1,100 - -

Bell et al. (2005) (all ages) 87 $760 90 $800 - -

Levy et al. (2005) (all ages) 120 $1,100 130 $1,100 - -

Morbidity

Hospital admissions--respiratory causes (ages > 65) 160 $4.0 170 $4.2 - -

Hospital admissions--respiratory causes (ages < 2) 84 $0.87 85 $0.88 - -

Emergency room visits for asthma (all ages) 86 $0.033 87 $0.034 - -

Minor restricted-activity days (ages 18 - 65) 160,000 $10 160,000 $10 - -

School absence days 51,000 $4.7 53,000 $4.9 - - 1 Rounded to two significant digits; no confidence intervals provided.
Table 3: Estimated state-level health impacts avoided1 due to the CSAPR and MATS2

—incidences of premature 

mortality3 and value3 (millions of dollars, 2007$) of mortality and morbidity impacts

CSAPR 

Participation

CSAPR Benefits MATS Benefits CSAPR Plus MATS Benefits

Mortality Valuation Mortality Valuation Mortality Valuation 

Alabama PM2.5, O3 390–1,000 $3,400–$8,300 140–360 $1,200–$3,000 530–1,400 $4,600–$11,000

Arizona5 14–35 $120–$290 14–35 $120–$290

Arkansas O3 210–530 $1,800–$4,400 96–250 $820–$2,000 300–780 $2,600–$6,400

California5 6–14 $48–$120 6–14 $48–$120

Colorado5 53–140 $460–$1,100 53–140 $460–$1,100

Connecticut 130–340 $1,100–$2,800 35–90 $300–$750 170–430 $1,400–$3,500

Delaware 57–150 $500–$1,200 13–32 $110–$270 70–180 $600–$1,500

District of Columbia 30–77 $260–$640 6–15 $51–$120 36–92 $310–$760

Florida O3 630–1,600 $5,400–$13,000 280–730 $2,400–$6,000 910–2,300 $7,800–$19,000

Georgia PM2.5, O3 610–1,600 $5,300–$13,000 190–490 $1,700–$4,100 800–2,000 $6,900–$17,000

Idaho5 3–7 $22–$54 3–7 $22–$54

Illinois PM2.5, O3 610–1,600 $5,200–$13,000 220–570 $1,900–$4,700 830–2,100 $7,200–$18,000

Indiana PM2.5, O3 540–1,400 $4,700–$11,000 110–290 $960–$2,400 650–1,700 $5,600–$14,000

Iowa PM2.5, O3 95–240 $820–$2,000 61–160 $520–$1,300 160–400 $1,300–$3,300

Kansas PM2.5 84–220 $730–$1,800 60–150 $520–$1,300 140–370 $1,200–$3,100

Kentucky PM2.5, O3 550–1,400 $4,700–$12,000 83–210 $710–$1,800 630–1,600 $5,400–$13,000

Louisiana O3 210–540 $1,800–$4,400 110–290 $970–$2,400 320–830 $2,800–$6,800

Maine 24–63 $210–$520 8–20 $68–$170 32–83 $280–$680

Maryland PM2.5, O3 420–1,100 $3,700–$9,000 84–210 $720–$1,800 510–1,300 $4,400–$11,000

Massachusetts 160–400 $1,400–$3,300 52–130 $450–$1,100 210–540 $1,800–$4,400

Michigan PM2.5, O3 560–1,400 $4,800–$12,000 160–410 $1,400–$3,400 720–1,800 $6,200–$15,000

Minnesota PM2.5 79–200 $680–$1,700 57–140 $490–$1,200 140–350 $1,200–$2,900

Mississippi O3 230–580 $2,000–$4,800 93–240 $800–$2,000 320–820 $2,800–$6,800

Missouri PM2.5, O3 340–870 $2,900–$7,200 160–410 $1,400–$3,400 500–1,300 $4,300–$11,000

Montana5 3–8 $25–$62 3–8 $25–$62

Nebraska PM2.5 31–81 $270–$670 28–72 $240–$600 59–150 $510–$1,300

Nevada5 4–10 $33–$82 4–10 $33–$82

New Hampshire 32–83 $280–$690 10–25 $84–$210 42–110 $360–$890

New Jersey PM2.5, O3 470–1,200 $4,000–$9,900 120–320 $1,100–$2,600 590–1,500 $5,100–$13,000

New Mexico5 9–24 $79–$200 9–24 $79–$200

New York PM2.5, O3 800–2,000 $6,900–$17,000 170–440 $1,500–$3,700 970–2,500 $8,400–$21,000

North Carolina PM2.5, O3 780–2,000 $6,700–$16,000 190–480 $1,600–$3,900 970–2,500 $8,300–$20,000

North Dakota 3–8 $28–$68 7–19 $63–$150 11–27 $90–$220

Ohio PM2.5, O3 1,300–3,300 $11,000–$27,000 220–560 $1,900–$4,600 1,500–3,900 $13,000–$32,000

Oklahoma O3 160–410 $1,400–$3,400 120–300 $1,000–$2,500 280–720 $2,400–$5,900

Oregon5 5–12 $39–$97 5–12 $39–$97

Pennsylvania PM2.5, O3 1,200–3,000 $10,000–$25,000 210–530 $1,800–$4,400 1,400–3,600 $12,000–$29,000

Rhode Island 32–83 $280–$680 11–29 $96–$240 44–110 $370–$920

South Carolina PM2.5, O3 400–1,000 $3,400–$8,400 130–330 $1,100–$2,700 520–1,300 $4,500–$11,000

South Dakota 9–22 $75–$180 11–27 $92–$230 19–50 $170–$410

Tennessee PM2.5, O3 680–1,700 $5,800–$14,000 140–370 $1,200–$3,000 820–2,100 $7,000–$17,000

Texas PM2.5, O3 700–1,800 $6,100–$15,000 460–1,200 $4,000–$9,700 1,200–3,000 $10,000–$25,000

Utah5 8–22 $74–$180 8–22 $74–$180

Vermont 18–46 $150–$380 4–10 $34–$83 22–56 $190–$460

Virginia PM2.5, O3 640–1,600 $5,500–$14,000 120–300 $1,000–$2,500 760–1,900 $6,500–$16,000

Washington5 12–31 $100–$250 12–31 $100–$250

West Virginia PM2.5, O3 280–720 $2,400–$5,900 38–96 $320–$790 320–820 $2,700–$6,700

Wisconsin PM2.5, O3 170–450 $1,500–$3,700 87–220 $750–$1,800 260–670 $2,200–$5,500

Wyoming5 2–6 $20–$49 2–6 $20–$49

National Total4

14,000—

35,000

$120,000—

$290,000

4,200—

11,000

$36,000—

$89,000

18,000—

46,000

$150,000—

$380,000 1 Some states may show benefits even if emissions are not reduced within those states due to pollution transport across state boundaries. 2 State-level MATS benefits estimates assume that the distribution of health-co-benefits for the final policy is equivalent to the modeled interim 

scenario. Differences in the scenarios may lead to over- or underestimates of benefits in some states.

3 Range reflects estimates of PM2.5-related benefits using Pope et al. (2002) and Laden et al. (2006) and ozone-related benefits using Bell et al. 

(2004) and Levy et al. (2005); rounded to two significant digits; no confidence intervals provided. 4 State results do not sum to national total due to rounding. 5 States in the Western U.S. are not expected to be significantly impacted by the CSAPR, their benefits are not presented at the state-level.
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United States

Environmental Protection

Agency

Office of Air Quality Planning and Standards

Health and Environmental Impacts Division

Research Triangle Park, NC

Publication No. EPA-452/R-11-014

December, 2011