1. Air Science Policy: The U.S. Perspective on
Addressing Future Air Quality Challenges
C. Arden Pope III
Mary Lou Fulton Professor of Economics
Presented at:
Air Science Policy Forum
Dublin, Ireland
April 15, 2013

2. Early “Killer smog” episodes demonstrated that air pollution at extreme
levels can contribute to respiratory and cardiovascular disease and death
Dec. 5-9, 1952: London--1000’s of excess deaths
Dec. 1-5, 1930: Meuse Valley, Belgium
60 deaths (10x expected)
Oct. 27-31, 1948: Donora, PA
20 deaths, ½ the town’s population fell ill
Respiratory and cardiovascular
disease and death

3. The killer episodes spurred air pollution policies in the U.S.
Killer Smog
(and related research)
Public Policy Results
1955-1967: Air pollution control
acts
1967, 1970: Clean Air Act,
Major Amendments, National
Environmental Policy Act
1977 & 1990: Major
Amendments to Clean Air Act
1980’s: Elimination of
extreme “Killer Smog”
episodes & Improved air
quality
1930: Meuse Valley, Belgium
1948: Donora, PA
1952: London, England
By the 1980’s, many thought the air pollution problem
had been solved…

4. …but by the early 1990’s, several studies suggested
that even moderate levels of air pollution could
contribute to significant health effects.

5. Utah Valley, 1980s
• Winter inversions trap local pollution
• Natural test chamber
• Local Steel mill contributed ~50% PM2.5
• Shut down July 1986-August 1987
• Natural Experiment

6. Large difference in air quality
when inversions trap air pollution in valley
Utah Valley: Clean day
Utah Valley: Dirty day
(PM10 = 220 mg/m3)

7. mg/m3
/NumbersofAdmissions
0
50
100
150
200
250
300
PM10 concentrations Children's respiratory hospital admissions
Mean PM10
levels for
Months
Included
Mean High
PM10
levels for
Months
Included
Pneumonia
and
Pleurisy
Bronchitis
and
Asthma
Total
Children's Respiratory Hospital Admissions
Fall and Winter Months, Utah Valley
Sources: Pope. Am J Pub Health.1989; Pope. Arch Environ Health. 1991
When the steel mill was open, total children’s hospital
admissions for respiratory conditions approx. doubled.mg/m3
/NumbersofAdmissions
0
50
100
150
200
250
300
PM10 concentrations Children's respiratory hospital admissions
Mean PM10
levels for
Months
Included
Mean High
PM10
levels for
Months
Included
Pneumonia
and
Pleurisy
Bronchitis
and
Asthma
Total
Children's Respiratory Hospital Admissions
Fall and Winter Months, Utah Valley
Sources: Pope. Am J Pub Health.1989; Pope. Arch Environ Health. 1991
Mill
Open
Mill
Closed

8. %increaseinmortality
0
1
2
3
Estimates from
meta analysis
Estimates from Multicity studies
29cities
(Levyetal.2000)
GAM-basedstudies
(Stiebetal.2002,2003)
Unadjusted
(Andersonetal.2005)
6U.S.cities
(KlemmandMason2003)
8Canadiancities
(BurnettandGoldberg2003)
9Californiancities
(Ostroetal.2006)
10U.Scities
(Schwartz2000,2003)
14U.Scities,case-crossover
(Schwartz2004)
NMMAPS,20-100U.S.cities
(Dominicietal.2003)
APHEA-2,15-29Europeancities
(Katsouyannietal.2003)
9Frenchcities
(LeTertreetal.2002)
13Japanesecities
(Omorietal.2003)
NonGAM-basedstudies
(Stiebetal.2002,2003)
Publicationbiasadjusted
(Andersonetal.2005)
7Koreancities
(Leeetal.2000)
20g/m
3
PM10
20g/m
3
PM10
20g/m
3
PM10
20g/m
3
PM10
20g/m
3
PM10
10g/m
3
PM2.5
20g/m
3
PM10
10g/m
3
PM2.5
10g/m
3
PM2.5
20g/m
3
PM10
20g/m
3
PM10
20g/m
3
PM10
20g/m
3
BS
40g/m
3
TSP
20g/m
3
SPM
ReviewofAsianLit.--8studies
(HEIReport,TableTS2)20g/m
3
PM10
20g/m
3
PM10
20g/m
3
PM10
Estimates from
meta analysis
from Asian Lit
PAPAStudies--4studies
(HEIReport,TableTS2)
AsianLit.incorporatingPAPAstudies
(HEIReport,TableTS2)
18LatinAm.studies
(PAHO2005)
20g/m
3
PM10
10 mg/m3 PM2.5 or 20 mg/m3 PM10 → 0.4% to 1.5%
increase in relative risk of mortality—Small but
remarkably consistent across meta-analyses and multi-city studies.
Daily time-series studies ***of over 200 cities***

9. • Case-crossover study of acute ischemic coronary
events (heart attacks and unstable angina) in 12,865
cardiac patients on Utah’s Wasatch Front
• Patients underwent coronary angiography
• Results showed associations between air pollution and
cardiovascular disease
2006;114:2443-48
Evidence mounted suggesting that air pollution has significant
impacts on cardiovascular health.

10. %
-10.00
-5.00
0.00
5.00
10.00
15.00
20.00
Figure 2. Percent increase in risk (and 95% CI) of acute coronary events associated with
10 mg/m3
of PM2.5, stratified by various characteristics.
Allacutecoronary
SubsequentMI
UnstableAngina
Age<65
Age>=65
Male
Female
Smoking
NonSmoking
BMI<30
BMI>=30
CHF,yes
CHF,no
Hypertension,yes
Hypertension,no
Hyperlipidemia,yes
Hyperlipidemia,no
Diabetes,yes
Diabetes,no
Familyhistory,yes
Familyhistory,no
# of
Diseased
Vessels
# of
Risk Factors
0
1
2
3
0
1
2
3
4+
IndexMI
Just a few days of PM exposure significantly increased
risk for heart attacks and ischemic heart disease.

11. Short-term changes in air pollution exposure
are associated with:
• Daily death counts (respiratory and cardiovascular)
• Hospitalizations
• Lung function
• Symptoms of respiratory illness
• School absences
• Ischemic heart disease
• Etc.

12. Longer-term air pollution exposure has
been linked to even substantially larger
health effects.

13. Median PM2.5 for aprox. 1980
8 10 12 14 16 18 20 22 24 26 28 30 32 34
AdjustedMortalityfor1980(Deaths/Yr/100,000)
600
650
700
750
800
850
900
950
1000
Age-, sex-, and race- adjusted population-
based mortality rates in U.S. cities for 1980
plotted over various indices of particulate
air pollution (From Pope 2000).

14. Methods:
• 14-16 year prospective follow-up of 8,111 adults living in six U.S. cities.
• Monitoring of TSP PM10, PM2.5, SO4, H+, SO2, NO2, O3 .
• Data analyzed using survival analysis, including Cox Proportional Hazards Models.
• Controlled for individual differences in: age, sex, smoking, BMI, education, occupational
exposure.
An Association Between Air Pollution and
Mortality in Six U.S. Cities
Dockery DW, Pope CA III, Xu X, Spengler JD,
Ware JH, Fay ME, Ferris BG Jr, Speizer FE. 1993
In 1993, the Harvard “Six-Cities” study was published.
It followed > 8,000 adults for 14-16 years to observe
associations between air pollution and risk of death.

15. Adjusted relative risk of dying were
almost linearly associated with air pollution.

17. Increased levels of fine PM increased risk of death.

18. Air pollution is most strongly associated with deaths from
ischemic heart disease, dysrhythmias, heart failure, cardiac
arrest and related heart disease.
RR(95%CI)
0.65
0.70
0.75
0.80
0.85
0.90
0.95
1.00
1.05
1.10
1.15
1.20
1.25
1.30
1.35
1.40
AllCardiovascular
plusDiabetes
Ischemicheart
disease
Dysrhythmias,Heart
failure,Cardiacarrest
Hypertensive
disease
OtherAtherosclerosis,
aorticaneurysms
Cerebro-
vascular
OtherCardio-
vascular
Diabetes
Respiratory
Diseases
COPDand
alliedconditions
Pneumonia,
Influenza
Allother
respiratory
2004;109:71-77.
John Godleski
Risk ratios for
death
associated
with a 10 µg/m3
change in PM2.5
Dot sizes
indicate the
number of
deaths for each
cause.

19. The Six-Cities and ACS studies have undergone
extensive peer review and analyses. Their results
are reproducible and remarkably robust.

20. Legal uncertainty largely
resolved with 2001
unanimous ruling by the
U.S. Supreme Court.

21. Percentincreaseinmortalilyrisk(95%CI)
-10
0
10
20
30
40
50
60
70
80
90
100
110
120
180
190
All Cause CPD CVD IHD
U.S. Medicare Cohort studies:
•Eftim et al. Epidemiology 2008
•Zegar et al. EHP 2008
Cohorts of Medicare participants cities of the 6-cities and ACS study, plus all U.S.
U.S. Medicare Cohort Studies

22. Modern air pollution science has resulted in new and tighter
standards in the U.S. for air pollution—especially PM2.5
Contemporary
Science
Public Policy Results
1997: New PM2.5 standards
(24-hr 65 µg/m3,
annual 15 µg/m3)
2006: PM2.5 24-hr standard
revised (35 µg/m3)
2012: PM2.5 annual standard
revised (12 µg/m3)
1990 - 2013: Continued
general improvements in
air quality
1989+ Time-series studies
1993+ Prospective cohort
mortality studies
1997+ 100’s of other
including tox.,
clinical, etc.

23. So, an obvious question—
Has reducing air pollution resulted in
substantial and measurable
improvements in human health?

24. - Matching PM2.5 data for
1979-1983 and 1999-2000 in
51 Metro Areas
- Life Expectancy data for
1978-1982 and 1997-2001 in
211 counties in 51 Metro areas
- Evaluate changes in Life
Expectancy with changes in
PM2.5 for the 2-decade period
of approximately 1980-2000.
Fine-Particulate Air Pollution and Life
Expectancy in the United States
C. Arden Pope, III, Ph.D., Majid Ezzati, Ph.D., and Douglas W.
Dockery, Sc.D.
January 22, 2009
Do cities with bigger improvements in air quality have bigger
improvements in health, measured by life expectancy?

25. Reduction in PM2.5, 1980-2000
0 2 4 6 8 10 12 14
0.0
Reduction in PM2.5, 1980-2000
0 2 4 6 8 10 12 14
ResidualchangesinLEcontrollingforcovariates
-2.5
-2.0
-1.5
-1.0
-0.5
0.0
0.5
1.0
1.5
2.0
2.5
22
47
49
45
4
10
17
19
46
48
6
4350
24
21
36
8
34
20
7
25
1
11
12
14
44
51
27
3 28
30
32
13
18
26
9
29
23
37
38
40
15
33
5
2
35
31
16
39
41
42
B
YES. On average, the greater the reduction in air
pollution, the greater the increase in life expectancy.

26. Francesca Dominici

27. Brook, Rajagopalan, Pope, et al. 2011
AHA Scientific Statement, PM and CVD

28. Ambient Concentrations ( g/m3)
$
CT
CM
Marginal Health
Costs of Pollution

29. Ambient Concentrations ( g/m
3
)
$
Marginal Cost
of Abatement
Marginal Health Cost
of Pollution
C
T
C* C
M

30. In Six-Cities study, adjusted relative risk of dying were
almost linearly associated with air pollution.

31. In ACS study, adjusted relative risk of dying were
almost linearly associated with air pollution.

32. Ambient Concentrations ( g/m
3
)
$
Marginal Cost
of Abatement
Marginal Health Cost
of Pollution
C*

34. 0 60 120 180 240 300
AdjustedRelativeRisk
1.0
1.5
2.0
2.5
<3
cigs/day
estimated daily dose of PM2.5, mg
23+
cigs/day
8-12
cigs/day
13-17
cigs/day
18-22
cigs/day
4-7
cigs/day
Pope, Burnett, Krewski, et al. 2009.
Figure 1. Adjusted relative
risks (and 95% CIs) of IHD
(light gray), CVD (dark
gray), and CPD (black)
mortality plotted over
estimated daily dose of
PM2.5 from different
increments of current
cigarette smoking.
Diamonds represent
comparable mortality risk
estimates for PM2.5 from air
pollution. Stars represent
comparable pooled relative
risk estimates associated
with SHS exposure from
the 2006 Surgeon
General’s report and from
the INTERHEART study.

35. Ambient Concentrations ( g/m
3
)
$
C* CH
Marginal Costs
of Abatement
Marginal Health
Costs of Pollution
CNC

36. Ambient Concentrations ( g/m
3
)
$
C* CH
Marginal Costs
of Abatement
Marginal Health
Costs of Pollution
CNC

37. Ambient Concentrations ( g/m
3
)
$
C* CH
Marginal Costs
of Abatement
Marginal Health
Costs of Pollution
CNC
Pollution Abatement

38. Ambient Concentrations ( g/m
3
)
$
C* CH
Marginal Costs
of Abatement
Marginal Health
Costs of Pollution
CNC

39. Ambient Concentrations ( g/m
3
)
$
C* CH
Marginal Costs
of Abatement
Marginal Health
Costs of Pollution
CNC

40. Ambient Concentrations ( g/m
3
)
$
C* CH
Marginal Costs
of Abatement
Marginal Health
Costs of Pollution
CNC

41. Finally,
This stylized approach ignores various uncertainties and
complications including:
 Interactive multi-pollutants,
 Issues of environmental justice,
 How do efforts to reduce traditional air pollutants
complement or diverge from efforts to address climate
change and is there a reasonable way to integrate these
efforts.
Thank you.