WHO European Centre for Environment and HealthWHO European Centre for Environment and Health

Recent WHO Findings on Health Recent WHO Findings on Health RisksRisks

• Introduction Introduction • Projects Projects • Key findingsKey findings• Follow-upFollow-up

Jürgen Schneider Jürgen Schneider Project MangerProject Manger

WHO ECEH, Bonn, GermanyWHO ECEH, Bonn, Germany

TASK FORCE INTEGRATED ASSESSMENT MODELLINGTASK FORCE INTEGRATED ASSESSMENT MODELLING

(Twenty-eight session, Haarlem, 7-9 May 2003(Twenty-eight session, Haarlem, 7-9 May 2003 ))

WHO European Centre for Environment and HealthWHO European Centre for Environment and Health

WHO Air Quality and Health WHO Air Quality and Health

• Methodology of health impact assessment (participation in AIRNET & APHEIS)

• Systematic Review of Health Aspects of Air Quality in Europe (focus on ‘priority pollutants’ PM and ozone, NO2)

• Update of WHO Air Quality Guidelines

• Health impacts of transport-related air pollution

• Health risks of POPs from LRTAP

• AQ strategies for NIS

• Capacity building in air quality monitoring and assessment (NIS & ALB)

WHO European Centre for Environment and HealthWHO European Centre for Environment and Health

WHO Project WHO Project Systematic Review of Health Aspects of Air Quality in EuropeSystematic Review of Health Aspects of Air Quality in Europe

(2002-2004)(2002-2004)

Purpose:To provide the EC DG Environment (& CAFE) with a systematic, periodic, scientifically independent review of the health aspects of air quality in Europe.

Scientific Advisory Committee (SAC)

Guides the overall review

WHO Working Group (SAC + invited experts)Up-date the scientific evidence on health aspects of air pollution, agree on answers

WHO European Centre for Environment and HealthWHO European Centre for Environment and Health

Systematic Review

Health aspects of PM, NO2 and ozone

• Focused on twelve questions received from the CAFE Steering Group

• Used state-of-the-art knowledge on epidemiology and toxicology

• Short answers, supported by more extensive justifiactions

• Extensively reviewed

• Presented to stakeholders in Brussels

• Now available on web:

http://www.euro.who.int/document/e79097.pdf

WHO European Centre for Environment and HealthWHO European Centre for Environment and Health

1) Is there new scientific evidence to justify reconsideration of the current WHO Guidelines for the pollutant?

Particulate matter: Yes • Association of PM exposure with health effects have been strengthened• Fine PM (measured as PM2.5) strongly associated with mortality and

other endpoints• PM10 is still considered to be a relevant metrics• BS should be re-evaluated

Ozone: Yes• Evidence from epidemiological studies on effects of short-term exposure

to ozone (mortality and morbidity)• Evidence of long-term effects on lung function

Nitrogen dioxide: No• Very limited new evidence on potential mechanisms of NO2 effects• Reiteration of important role of NO2 as indicator for traffic related air

pollution and precursor of both ozone and secondary PM

Systematic Review

WHO European Centre for Environment and HealthWHO European Centre for Environment and Health

2 )   Which effects can be expected of long-term exposure?

PM• Long-term exposure may lead to a marked reduction in life

expectancy. Increases in lower respiratory symptoms and reduced lung function in children, COPD and reduced lung function in adults

Ozone• Reduced lung functions in children

NO2

• Some evidence for decreased lung function and increase of risk of respiratory syndroms

Systematic Review

WHO European Centre for Environment and HealthWHO European Centre for Environment and Health

3)   Is there a threshold below which no effects on health are expected to occur in all people?

For all three pollutants: No

• The population distribution of susceptibility may be such that effects are expected at very low levels

• Thresholds differ depending on endpoint selected• Increasingly sensitive epidemiological study designs have identified

adverse effects of air pollution at increasingly lower levels

Replacing the threshold concept with a more complete concept using exposure risk functions should be considered

Systematic Review

WHO European Centre for Environment and HealthWHO European Centre for Environment and Health

4)   Are the effects dependent on the subject’s characteristics?

PM • Elderly and those with pre-existing disease are at higher risk• Socially disadvantaged and poorly educated are at higher risk for

mortality

Ozone• Mortality and hospital admissions increase with age• Effects on asthmatic children might be greater• Larger effects in children which spend more time outdoor

Nitrogen dioxide

Systematic Review

WHO European Centre for Environment and HealthWHO European Centre for Environment and Health

6)   Is the considered pollutant per se responsible for effects on health?

PM: Yes – even though no single causative agent can be identified

Ozone: Yes

Nitrogen dioxide: A clear answer can not be given

Systematic Review

WHO European Centre for Environment and HealthWHO European Centre for Environment and Health

7)   For PM: which of the physical and chemical characteristics of particulate air pollution are responsible for health effects?

• Fine PM is more hazardous than larger particles• Metal content• Organic components such as PAH• Endotoxins• Extremely small particles (< 100 nm)

Systematic Review

WHO European Centre for Environment and HealthWHO European Centre for Environment and Health

10)  Which are the critical sources of the pollutant?

• Motor vehicle emissions• Other combustion processes• Wind-blown dust of crustal origin: less critical

Systematic Review

WHO European Centre for Environment and HealthWHO European Centre for Environment and Health

12)  What averaging period is most relevant from the point of view of protecting human health?

Particulate matter:

• Short-term (24 hours) and long-term (annual) guidelines are recommended

Ozone:

• Short-term: 8-hour average is appropriate • Long-term: associations are not clear enough to allow specific

recommendation

Nitrogen dioxide:

• Both, short-term (1 h) and long-term are warranted

Systematic Review

WHO European Centre for Environment and HealthWHO European Centre for Environment and Health

Follow-up: Meta-analysis to derive concentration-response functions for

Particualte matter• Mortality (cause-specific)• Hospital admissions (cause-specific)

Ozone• Mortality (cause-specific)• Hospital admissions (cause-specific)• Symtom exacerbation in astmatics

Nitrogen dioxide• The working group did not recommend the use of regression

coefficients for NO2 from regression models to assess the effect of NO2 by itself.

Systematic Review

WHO European Centre for Environment and HealthWHO European Centre for Environment and Health

Second round of questions by CAFE Steering Group

• Relevance of peak exposure? • Uncertainties• Specific populations at risk?• Why should we keep the annual AQG for NO2?• Other polluants relevant?

Systematic Review

WHO European Centre for Environment and HealthWHO European Centre for Environment and Health

• WHO AQG published in 2000, but work finalised in 1996 • Systematic review recommended an update for PM and ozone• Update a world-wide activity • Process initiated; request for funding• Finalise until end of 2004

Update WHO AQG

WHO European Centre for Environment and HealthWHO European Centre for Environment and Health

Joint UN/ECE WHO Task Force on Health

6. Meeting 22-23 May in Bonn

• Approaches to risk assessment• Modelling and assessment of health impacts of particulate matter and

ozone from long range transboundary air pollution • Relevance of secondary inorganic aerosols for PM-related health

effects • Is the AOT60 approach still appropriate?• Possible approaches to include effects on morbidity into IAM

WHO European Centre for Environment and HealthWHO European Centre for Environment and Health

CAFE WG on PM

PM is a priority pollutant of CAFE -> WG on PM

Revision of Position Paper on PMAttainability of current LV (stage I and II)Guidance on targets for CAFE/IAM, based on advice from WHO, but also

other considerations like attainability, cost-effectivness, etc. Draft version of the revised position paper will be discussed at a

stakeholder conference in October 2003

WHO European Centre for Environment and HealthWHO European Centre for Environment and Health

Health impacts of transport-related air pollution

ObjectiveThe objective of the WHO workshop is to provide a systematic literature review on transport-related health hazards.

Time schedule         15th July, submission of papers          1st September, the draft monograph for external review          Mid October 2003 - WHO WG Workshop in WHO Bonn

Office• End 2003 - finalizing the monograph Contents1. Factors Determining Emissions in the European Regions2. Contribution of Traffic to Ambient Air Pollution Levels in the

European Region3. Human Exposure to Transport Related Air Pollution and Dose4. Epidemiological Studies on Transport Related Health Effects5. Toxicological Studies on Transport-Related Health Effects6. Assessment of Health Hazards of Transport-Related Air

Pollution

WHO European Centre for Environment and HealthWHO European Centre for Environment and Health

TASK FORCE INTEGRATED ASSESSMENT MODELLINGTASK FORCE INTEGRATED ASSESSMENT MODELLING

(Twenty-eight session, Haarlem, 7-9 May 2003(Twenty-eight session, Haarlem, 7-9 May 2003 ))