Air quality management:Air quality management:Health implicationsHealth implications

Marco Martuzzi

World Health Organization, Regional Office for Europe

European Centre for Environment and Health, Rome Division

WHO Regional Office for Europe

Role of air pollution on healthRole of air pollution on health

§ Large amount of data§ Important role established§ Mortality, morbidity and hospital admission, lung

development and function, respiratory symptoms§ Short- and long-term effects§ Adults, children, elderly, other susceptible groups

WHO Monograph: The effects of air pollution on children’s health and development: a review of the evidence

Proportion of population affected

Severity

Air pollution and health: health effects “pyramid”

Early mortalityCardio-respiratory disease

Hospital admissionAsthma exacerbationDoctor consultancy

Impaired physical conditionPharmaceuticals use

Symptoms, discomfortReduced lung function

Sub-clinical effects

Early mortalityCardio-respiratory disease

Hospital admissionAsthma exacerbationDoctor consultancy

Impaired physical conditionPharmaceuticals use

Symptoms, discomfortReduced lung function

Sub-clinical effects

WHO Regional Office for Europe

Some questionsSome questions

§ Independent and combined effects of various pollutants§ Interaction with other risk factors and allergens§ Particles size and composition§ Relevant time window for exposures

§ Sources (especially from transport, which vehicles)§ Exposure assessment and distribution in the population§ Assessment of health impact and costs§ Development of protective and preventive policies in

different countries

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Assessing the health impact of air pollutionAssessing the health impact of air pollution

§ Risks have been identified, and dose-response relationships have been characterised for several pollutants and health endpoints§ Compared to other risk factors risks are small§ Exposure is ubiquitous, majority of people exposed§ Need to assess overall public health relevance of

air pollution§ Air quality monitoring data increasingly available

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Assessing the impactAssessing the impact

§ Policy makers under growing pressure§ Underlying cost-benefit type question, “what would

we gain if we could reduce concentrations to X?Ӥ Metrics for health impact: attributable risks (risk

assessment studies), years of life lost (YLL), and economic evaluations§ Air pollution impact studies have been published,

e.g., France-Switzerland-Austria (Kuenzli 2000); UK (Hurley 2000), Italy (2001), US, …

WHO Regional Office for Europe

APHEIS recent resultsAPHEIS recent results

§ Air Pollution and Health: A European Information System § 23 cities in Europe, 36 million people§ 3rd phase of project (results released 6 Sept)§ “11 375 deaths, including 8 053 cardiopulmonary

and 1 296 lung cancer deaths, could be prevented annually if long-term exposure to the annual mean of converted PM2.5 levels were reduced to 20 µg/m3 in each city”

WHO Regional Office for Europe

Methods for air pollution HIAMethods for air pollution HIA

§ Use PM as a summary indicator of all pollutants (cannot evaluate separate roles); recent studies include ozone§ Risk functions for selected outcomes§ Exposure estimates, usually average

concentrations for large population§ Observed rates or prevalence§ “Prudent” estimates, i.e., identify part of the health

effects effectively attributable to AP

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8 Italian Cities8 Italian Cities

§ PM10 data from monitoring stations§ Mortality, morbidity, hospital admission§ Average concentration in 52.6 µg/m3

§ Estimate rates or prevalences predicted at lower concentrations§ Compare with observed rates§ Reference PM10 levels: 20, 30, 40 µg/m3

§ “Conservative” risk coefficients, e.g. for long term mortality: 1.026 / 10 µg/m3 (95% CI 1.009 – 1.043)

Reference PM10 level: 30µg/m3

Reference PM10 level: 20µg/m3

Cause Attr prop (%) (95% CI)

Nr attr cases

Attr prop (%) (95% CI)

Nr attr cases

Mortality (Adults aged 30+,

excluding accidental causes)

4.7

(1.7, 7.5)

3 472 7.0

(2.6, 10.9)

5 108

Hospital admissions for CVD

causes

1.7

(1.2, 2.5)

2 710 2.6

(1.7, 3.7)

4 057

Hospital admissions for

respiratory disease

3.0

(2.5, 3.7)

1 887 4.5

(3.7, 5.5)

2 803

Acute bronchitis (aged <15) 28.6

(18.4,32.9)

31 524 36.3

(25.1, 39.7)

40 036

Asthma exacerbation (aged

<15)

8.7

(8.1, 9.2)

29 730 12.5

(11.7, 13.3)

42 870

Asthma exacerbation (aged

15+)

0.8

(0, 1.5)

11 360 1.2

(0, 2.3)

17 047

Restricted activity days (aged

20+)

14.3

(12.5, 15.9)

2 702 461 20.0

(17.7, 22.1)

3 776 387

Occurrence of respiratory

symptoms

11.3

(3.7, 16.0)

10 409 836 16.1

(5.5, 22.2)

14 788 287

WHO Regional Office for Europe

MortalityMortality

§ Long term vs short term§ Who dies? When? (Important especially for

economic evaluation)§ Estimate effects on life expectancy

Predicted total gain in life-years (millions) under various assumed reductions in ambient PM10 pollution in England and Wales, by delay to full effect and population

Delay to full effect (years) Population

Reduction in PM10 concentration,

µg.m–3 0 5 10 20 30

5 8.94 8.20 7.58 6.30 4.97 10 17.89 16.41 15.17 12.61 9.96 15 26.85 24.64 22.78 18.94 14.97

Alive at start of 2000

25 44.81 41.13 38.03 31.63 25.01

5 8.02 8.00 7.96 7.87 7.76 10 16.02 15.95 15.88 15.72 15.48 15 23.97 23.88 23.77 23.52 23.17

Born 2001 to 2135

25 39.77 39.61 39.45 39.04 38.46

From Hurley et al 2000

WHO Regional Office for Europe

Health Impact studiesHealth Impact studies

§ “First generation” studies§ Rough approximations involved, generally

thought to be “conservative”§ Work is needed on:

1. Methods for risk assessment of air pollution2. Interpretation and use of results in public health and risk

management

MORTALITY Total Mortality Cardiovascular Mortality Respiratory Mortality MORBIDITY Hospital Admissions Respiratory Disease Hospital Admissions Respiratory Dis <15 Years Hospital Admissions Respiratory Dis 15-64 Years Hospital Admissions Respiratory Dis 65+ Years Hospital Admissions Asthma <15 Years Hospital Admissions Asthma >15-64 Years Hospital Admissions COPD Hospital Admissions Cardiovascular Disease Hospital Admissions Congestive Heart Elderly Acute Myocardial Infarction Chronic Bronchitis Chronic Bronchitis >25 Years Acute Bronchitis < 15 Years Asthma Attacks Children Asthma Attacks Adults

WHO Regional Office for Europe

ConclusionsConclusions

§ Need to fill the knowledge gap between laboratory, clinical, epidemiological evidence and policy§ Make action on AP more compelling§ Need to improve methodology and evaluate

implications more thoroughly § HIA transport: Noise, accidents, cycling and

walking, psychosocial effects

www.euro.who.int/healthimpactwww.euro.who.int/hearts