Air Pollution and Health: An introduction

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Air Pollution and Health An introduction

• Ferran Ballester

2
Air pollution projects involvedAPHEAAPHEISEME
CAS

• Unit of Epidemiology Statistics
• Valencian School of Studies for Health-EVES

3
Literature

• There are many articles and books on air
  pollution and health
• There are also useful resources in Internet.

4
OBJECTIVES

• Introduce the basic concepts on air pollution and
  health
• Comment on the most used epidemiological designs
• Present the results of some of the main studies
  carried out in recent years

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Air, Water and Places
Hippocrates
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Air Pollution Major Episodes in the mid XXth
century

• Meuse Valley, Belgium (1930)
• Donora, Pennsilvania, USA (1948)
• London, UK (1952)

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The London Fog
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The London Fog
1000
5,000
900
4,500
800
4,000
700
3,500
600
3,000
Daily deaths, London
500
2,500
400
2,000
Black Smoke Central Hall mg/m3
300
1,500
200
1,000
100
0,500
0
0,000
1
2
3
4
5
6
7
8
9
10
11
12
13
14
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December 1952
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Anual average of black smoke (in ?g/m3) London
1958-1971.
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Major emission sources of air pollutants

SO2
VOCs
NOX
PM
Pb
Domestic Dwellings
Power Generation
Industry
Stationary Emission Sources
CO
NOX
VOCs
Pb
PM
Diesel
Mobile Emission Sources (Road Traffic)
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Major Air Pollutants (1)
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Major Air Pollutants (2)
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Health Effects of Air Pollution

• Mortality
• Cardiopulmonary Hospitalizations
• Emergency department or outpatient visits
• Symptomatic exacerbations
• Changes in lung function
• Cardiopulmonary symptoms
• Upper respiratory illnesses
• Lower respiratory illnesses

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Other Effects of Air Pollution

• Immune System Allergies
• Allergic Asthma, Allergic Rhinoconjunctivitis
• Extrinsic Allergic Alveolitis / Hypersensitivity
• Central Nervous System
• Toxic Damage of Nerve Cells
• Mental retardation
• Carcinogenic Effects
• Lung Cancer, Leukemia
• Reproductive effects
• Infant mortality, Low weight birth

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Deaths
ADVERSE HEALTH EFFECTS
Hospitalizations
Emergencies
Visits to doctors
Restricted activity
Medication
Symptoms
Annoyance, discomfort
Number of persons concerned
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Health effect assessment

• Toxicological studies
• Epidemiological studies

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Basic study designs in air pollution epidemiology
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Exposure assesment approaches in epidemiology of
air pollution

• Categorical exposure (high vs low)
• Measured (or modeled) outdoor concentrations
• Measurement of indoor and outdoor concentrations
• Estimation of individual exposure using indoor,
  outdoor along time-activity diaries
• Direct measurement of personal exposures
• Measurement of biomarkers of exposure

COST VALIDITY
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Results from some epidemiological studies

• Time series
• Cohort studies
• Intervention studies

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Relationship between the factors implied in the
time series epidemiological studies of air
pollution
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APHEA1 cities

Population gt 25,000,000
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APHEA1 FINDINGS

• 1. All pollutants studied have small acute
  effects on the daily total, cardiovascular and
  respiratory mortality.
• 2. Particulates and ozone levels were
  consistently associated with respiratory and COPD
  admissions.
• 3. NO2 levels were associated with asthma
  admissions.
• 4. The effects were observed in locations where,
  in the majority of days, air pollutant levels
  were well below the set (W.H.O., E.C.,
  U.S.E.P.A.) standards at that time.

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APHEA2

• EC Funded
• 30 cities
• 43 million inhabitants
• Period of study 5 years ( 1990-1996)

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The EMECAS Project
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EMECAS Combined estimates for mortality and air
pollution (1)
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EMECAS Combined estimates for mortality and air
pollution (2)
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EMECAS combined results for cardiovascular
admissions
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Harvard Six-City Cohort StudyRelative risk of
mortality and long-term exposure to PM2.5Dockery
et al, 1993
RR
Annual mean PM2.5 (?g/m3)
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Long-term exposure to fine particulates and
mortality in the ACS cohort (n500 000)Pope et
al, 2002
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Long term effectsin mortality and indicators of
traffic-related air pollution in the
NetherlandsHoek et al, 2002
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Intervention studies

• Close of a steel mill in the Utah Valley ?
  particle levels,
• ? morbidity, ? inflammatory process
• Ban on marketing and sale of smoky coal in
  Dublin ? black smoke levels,
• ? mortality
• Introduction of gas with low sulphur in Hong
  Kong ? levels of SO2 and SO4,
• ? mortality and respiratory
• symptoms in children

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Summary of estimates of particulate matter
effects (1)
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Summary of estimates of particulate matter
effects (2)
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Summary

• Main acute effects
• Increase in the number of deaths
• Increase in hospital admissions and emergency
  visits, especially for cardio-respiratory causes
• Alterations in lung performance, cardiac problems
  and other symptoms and discomfort
• Main chronic effects
• Increase in the risk of death
• Increased cardio-respiratory morbidity and
  decline of pulmonary function

35
References