1. Air Quality, Barcelona 17-18 June 2010
WHO assessments
of health effects
of air pollution
Michal Krzyzanowski, Sc.D.
European Centre for Environment and Health, Bonn Office
World Health Organization, Regional Office for Europe

2. Air quality and health – WHO assessment
This presentation:
• WHO assessments of health effects of air
pollution
• Air quality in Europe and related health effects
• Recent research results

3. WHO assessments of health risks
of air pollution
• Health effects of transport-related air pollution (WHO 2005)
• WHO Air quality guidelines – global update 2005 (WHO 2006)
• Health risk of particulate matter from LRTAP (WHO 2006)
• Health risk of ozone from LRTAP (WHO 2008)
• Annual reports on health effects of AP presented to CLRTAP
(http://www.unece.org/env/lrtap/lrtap_h1.htm )

4. WHO AQG: Global update:
Summary of updated AQG values
AQG levels recommended to be achieved everywhere in order
to significantly reduce the adverse health effects of pollution
Pollutant Averaging time AQG value
Particulate matter
PM2.5 1 year 10 µg/m3
24 hour (99th percentile) 25 µg/m3
PM10 1 year 20 µg/m3
24 hour (99th percentile) 50 µg/m3
Ozone, O3 8 hour, daily maximum 100 µg/m3
Nitrogen dioxide, NO2 1 year 40 µg/m3
1 hour 200 µg/m3
Sulfur dioxide, SO2 24 hour 20 µg/m3
10 minute 500 µg/m3

5. WHO AQG: Global update:
Particulate matter - annual mean
Annual mean PM10 PM2.5 Basis for the selected level
level (µg/m3) (µg/m3)
Interim target-1 70 35 Levels associated with about
(IT-1) 15% higher long-term mortality
than at AQG
Interim target-2 50 25 Risk of premature mortality
(IT-2) decreased by approximately 6%
compared to IT1
Interim target-3 30 15 Mortality risk reduced by
(IT-3) approximately 6% compared to
IT2 levels.
Air quality 20 10 Lowest levels at which total, CP
guideline and LCA mortality have been
(AQG) shown to increase (Pope et al.,
2002). The use of PM2.5
guideline is preferred.

6. Passing interim targets on the way towards
AQG
Effect
Exposure
AQG IT-2 IT-1

7. Long term exposure to PM and risk of mortality in ACS
cohort (ca. 0.5 million people followed for 16 years)
Source: Pope et al, JAMA 2002

8. Air quality and health – WHO assessment
This presentation:
• WHO assessments of health effects of air
pollution
• Air quality in Europe and related health effects
• Recent research results

9. PM2.5 concentration map, annual average, 2005
Based on the combination of scaled rural
and urban PM10 maps using region
specific PM2.5/PM10 ratios;
Population weighted
mean PM2.5:
EU27: 16.6 – 17.0 µg/m3
Spain: 16.1 – 17.6 µg/m3
Source: F. De Leeuw, J. Horalek, ETC/ACC, 2009

10. PM10 annual mean 1999-2008
PM10
trend(%/yr)
1999-2008
all stations
<-6 %/yr
-6 - -3 %/yr
-3 - 0 %/yr
PM10PM10 –
annual mean annual mean urban traffic rural
> 0 %/yr
50
40
30
20
10
0
source: ETC/ACC-AIRBASE February -2010 1998 2000 2002 2004 2006 2008
Source: F. de Leeuw, ETC ACC

11. PM10 concentration in Spanish cities
(urban background)
Madrid
60 Barcelona
Sevilla
Zaragoza
50 Málaga
Palma de Mallorca
Vitoria/Gasteiz
Oviedo
40
Pamplona/Iruña
Santander
Toledo
30 Badajoz
Bilbao
Córdoba
Granada
20
Móstoles
Jerez de la Frontera
San Sebastián/Donostia
10 Burgos
Salamanca
Albacete
0 Jaén
1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 Marbella
Torrejón de Ardoz
Source: Airbase

12. Effect indicator:
Premature mortality attributable to PM2.5 (2005)
Total:
492,000 premature
deaths per year;
4892,000 YLL
Spain:
373,100 YLL
Source: F. De Leeuw, J. Horalek, ETC/ACC, 2009

13. Health-relevant indicator of ozone levels
(SOMO35) in 2000 and expected in 2020
2000 2020
Source: CAFE 2004

14. 0
1000
2000
3000
4000
5000
Austria
EU25
Belgium
Denmark
Finland
France
Germany
Greece
Ireland
Italy
Luxembourg
Netherlands
2000
Portugal
Spain
2010 Sweden
UK
2020
Czech Rep.
Estonia
Hungary
Latvia
Lithuania
Poland
Slovakia
Slovenia
Source: CAFE 2004
Number of deaths attributed to O3 exposure in

15. Ozone levels in urban background locations of
selected countries, 1997 - 2007
14000 all countries
12000 AT
S O M O 3 5 u g /m 3 * d a y s
BE
10000
CH
8000 CZ
DE
6000
ES
4000 NL
2000 PL
SI
0
SK
97
98
99
00
01
02
03
04
05
06
07
GB
19
19
19
20
20
20
20
20
20
20
20
Source: AirBase
Note: all countries average based on data from varying number of
cities & countries (223 cities in 27 countries in 2008)

16. Air quality and health – WHO assessment
This presentation:
• WHO assessments of health effects of air
pollution
• Air quality in Europe and related health effects
• Recent research results

17. RR for deaths for all causes
per 10 µg/m3 annual mean PM10

18. Health impacts of ozone –
an update of evidence
Exposure-response curve for relation between long term O3
exposure and risk of death due to respiratory causes. Results of
analysis of ACS cohort of 448,000 adults followed for up to 18 years
RR per 10 ppb = 1.040 (95% CI 1.010 - 1.067)
(2-pollutant model with O3 and PM2.5)
Jerrett et al, NEJM 2009

19. Exposure to air pollution and infections, asthmatic and
allergic symptoms at 4 years old children
Birth cohort study of ca. 4,000 children in Netherlands. Exposure to traffic-related
air pollution based on validated models.
% change in risk (per inter-quartile range)
PM2.5 Soot NO2
Wheeze 23* 18 13
Doctor diagnosed asthma 15 15 12
Dry cough at night 11 13 11
Doctor diag. bronchitis -22 -10 -10
Ear / nose / throat 13 15* 17*
infections
Doctor diag. flu / cold 21* 18* 14
Allergen sensitivity (lab 55* 45* 32*
tests in sub-group)
* p<0.05
Source: Brauer, Hoek et al, ERJ 2007

20. Association between incident asthma with NO2*) as an
indicator of traffic-related air pollution
10-18 years old children followed for 8 years in S. California.
*) Effect estimates are over a 6.2-ppb (12.4 µg/m3) exposure contrast
Source: Jerrett EHP 2008

21. Respiratory effects of exposure to diesel traffic:
randomized study of 60 adults with asthma in London
Mean % changes during and after 2 h walk on Oxford street and Hyde Park
McCreanor et al, NEJM 2007

22. Ischemic and thrombotic effects of dilute diesel
exhaust inhalation in men with coronary heart disease
Myocardial inchemia during 15-minute intervals of exercise-induced
stress and exposure to diesel exhaust or filtered air in the 20 subjects
p<0.001
Mills et al, NEJM 2007

23. Reduction of PM exposure
and increase of life expectancy in the US
Fine particulate air pollution and life expectancy in the United States (Pope AC et
al, NEJM 2009): A decrease of 10 µg/m3 of PM2.5 associated with increase of life
expectancy by 0.61 years between 1980 and 2000
Reduction in PM accounts for 15% of overall increase in life expectancy

24. Potential reduction in YLL for two scenarios for PM2.5 reduction:
LV compliance and AEI-reduction target
Source: F. De Leeuw, J. Horalek, ETC/ACC, 2009

25. Conclusions
• Large and still growing body of evidence on adverse health
effects of air pollution (PM2.5, PM10, ozone)
• Impacts of air pollution cause loss of life expectancy by ca. 8.8
months in Europe (half a year in Spain) and contribute to
morbidity of adults and children
• Slight decrease in PM10 levels in urban areas in 2007-8 after
several years of no decrease in most countries of Europe – no
clear trends in Spanish cities
• Constant or growing (with exception of 2003 peak) O3 levels
• Population exposure reduction – recommended strategy for
Europe