The Health Effects of Air Pollution

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					 The Health Effects of Air
        Pollution
    Robert M. O’Keefe, Vice President
         Health Effects Institute


National Workshop on Improvement of
     Urban Air Quality of Pakistan
               Lahore
            December 2004
   Assessing the Health Effects of Air
               Pollution

• Health Effects Institute
• Air Pollution and Health Effects
• Public Health And Air Pollution in Asia
  Program “PAPA”
     • The existing Asia science literature
     • New Asian studies
• Conclusions
      The Health Effects Institute
• Founded in 1980 to provide impartial, high-quality science
  on health effects of vehicle and other emissions
• Joint and Equal Core Funding from
   – Government (U.S. EPA)
   – Industry (28 Worldwide Vehicle Manufacturers)
   – Today many partners worldwide: ADB, WHO, EU
     California ARB (CARB), Oil, other Industries
• Independent Expert Science Committees oversee and
  peer review all research
• Over 225 studies - Americas, Asia, Europe - ozone,
  carbon monoxide, particulate matter, diesel exhaust,
  benzene, butadiene, methanol, others
  Air Pollution and Health:
What we know about the effects
 Air Pollution has Many Effects
• Health
   – Respiratory, cardiovascular morbidity
   – Mortality
• Heritage
   – Nitric Sulfuric Acid erosion
• Natural Resources
   – Acidification (lake and stream biology)
   – Mercury deposition (fish tissue)
   – Visibility
• Agriculture
   – Ozone crop effects (~40% reduction in rice, soy yield in Pakistan
     city)
   –   *(Wahid 2003 Veranasi)
  Many Sources of Air Pollution in
              Asia
• Combustion             • Non-Combustion
  –   Open burning         – Agricultural
  –   Brick Kilns            cultivation
  –   Vehicles             – Street sweeping
  –   Trash burning        – Windblown sand
  –   Factories            – Unpaved roads
  –   Power generation     – Paved roads
                             (asbestos, rubber
  –   Cooking in slums       etc)
                           – Construction
Vehicle Emissions and Exposure
• Must consider all effects of the system:
  – different vehicle types -
     • 2 and 3 wheelers
     • cars
     • trucks and buses
  – vehicle plus fuels (and fuel components)
  – tailpipe emissions plus evaporative
    emissions
  – maintenance of system
    Major Vehicle/Fuel Emissions
• Carbon Monoxide           • Air Toxics
• Diesel Exhaust               – Aldehydes
                                   • formaldehyde
• Particulate Matter (PM)
                                   • acetaldehyde
• Lead
                                   • others
• Nitrogen Oxides (NOx)       –   Benzene
  and Hydrocarbons (HC)
                              –   1,3-butadiene
   – Precursors to Ozone
     and PM                   –   Methanol
• Nitrogen Dioxide            –   Polycyclic organic
                                  matter (e.g. PAHs)
             Health Effects
• Different Pollutants have Different Effects
   – Carbon Monoxide - circulatory system, heart
   – Ozone - respiratory system, lung
   – Lead - nervous system, brain
   – PM - lung, potential effects on heart
   – Diesel, Air Toxics - cancer, respiratory
     effects
• There are potential effects of the Mixture
             Health Effects
• Some populations more sensitive than others
  – Children
  – Elderly
  – people with heart and lung disease
• Asthma is growing
  – 150 million asthmatics worldwide
  – Increasing in most countries (2% to 5% per year)
  – Asthmatics much more sensitive to air pollution
        Particulate Matter (PM)
             Health Effects
• High levels of PM (e.g. 500 /m3) known to
  cause premature death
   – e.g. London 1952
• Recent studies in US, Europe, Asia, South
  America have found association of PM with
  death at much lower levels (< 50ugm3)
   – no evidence of a “threshold” (safe level)
• Progress made to identify a plausible
  biological mechanism for these effects;
  results not yet definitive
      PM - The Epidemiology Studies
• A Number of Epidemiology Studies




•   Europe Studies          Harvard 6 Cities Study
PM Health Effects - India, Thailand
                Source: Chhabra 2001, Pande 2001, Vichit-Vadakan, 2001

                        50                                         Asthma
                        45
% Increase in Effects



                                                                   COAD
                        40
                                                                   Cardiac
                        35
                        30                                         Cough
                        25                                         Phlegm
                        20                                         Lung Function
                        15
                                                                   Adult Resp.
                        10
                         5                                         Child Resp.

                         0                                         Nurse Resp.
                              Emergency       Chronic    Bangkok
                             Visits(Pande)     Effects
                                             (Chhabra)
              Ozone Health Effects
• Known to cause inflammation in respiratory tract
• Effects have been demonstrated for short term, long
  term effects are less certain
   – some people appear to develop “tolerance”
• Reduces ability to breathe (lung function) for some
  people
• Increases hospitalization for asthma, other lung
  diseases
• New US study finds Ozone mortality effects*
  (Domenchi et. al 2004)
                  Ozone Health Effects
• Some humans have been shown to have reduced lung
  function (measured as FEV1) after exposure to ozone
                                      Figure 1. Individual Response to
                                     Ozone Exposure (after Kulle, et al,
                                                  Am. Rev.)


                                -5

                                 0
          % Reduction in FEV1




                                 5

                                10

                                15

                                20

                                25
                                         0.1        0.15          0.2        0.25
                                30
                                                 Ozone Concentration (ppm)
           Diesel Health Effects
• Diesel Engines have substantial advantages:
   – higher fuel efficiency
   – lower CO and CO2 emissions
• However, they also emit high levels of :
   – particulate matter, NOx, and chemicals attached
     to the particles (e.g. PAHs)
• Two major types of health effects :
   – acute effects (e.g. exacerbating asthma)
   – cancer effects
      Diesel Effects on Childhood Illness
          (Brunekreef, et al Study in 24 Dutch schools)

        Increased Symptoms comparing High Truck Traffic
                 (>10,000) to Low Truck Traffic

2.2                                               asthma
 2
                                                  hayfever
1.8
                                                  phlegm
1.6
                                                  HD allergy
1.4
                                                  pet allergy
1.2

 1                                                wheeze last year
     Assessing Diesel Cancer Risk
• In general, some 30 studies of effects on
  workers have provided best data
• Consistent small (20-40%) increase in
  lung cancer associated with exposure
• Some questions about each study
• Leading International Agencies (WHO,
  IARC, US NIEHS, US EPA) have
  concluded diesel is a “probable human
  carcinogen”
               Sulfur Dioxide
• Emitted from fossil fuel combustion
     • especially from coal burning facilities, high sulfur fuels
• Can impair breathing in asthmatic children
  and adults
• Has been associated, along with PM, with
     • increased aggravation of heart and lung disease
     • premature mortality
• Recent study in Hong Kong (Lancet 2002)
  has found:
     • substantial reductions in SO2 emissions can result in
       measurable improvements in mortality and illness
                                  AIR POLLUTANT CONCENTRATIONS 1988 - 95 IN HONG KONG
                             80                HALF YEARLY MEAN LEVELS
                                   PM10                   Fuel restriction on sulphur
Micrograms per cubic metre
                             60




                                    NO2

                                    SO2                           50% reduction in SO2
                                                                  after the intervention
                             40




                                    O3
                             20




                                                                        No change in
                                                                       other pollutants
                             0




                                  1988    1989   1990   1991    1992     1993    1994   1995
                                                               Year
                                    REDUCTIONS IN DEATHS AFTER SULPHUR RESTRICTION
                   0           -1
   % Reduction in annual trend




                                                           -1.6%
                      -2




                                         -1.8%

                                                                   -2.4%
              -3




                                                 -2.8%
       -4




                                                                                   -4.2%
-5




                                                                           -4.8%
                   -6




                                         15-64   65+      15-64    65+     15-64   65+
                                          All causes     Cardiovascular    Respiratory
       Air Toxics Health Effects

• Benzene                  • 1,3 Butadiene
  – a “known human           – a “probable” or
    carcinogen”                “known” human
  – studies in U.S. and        carcinogen
    Chinese workers have     – studies in laboratory
    shown link between         animals and US and
    exposure and               Czech workers have
    increased leukemia         shown effects
• Metals                   • Aldehydes, PAH’s
                             – Cancers, Irritants
  – Range of effects,
    heart, reproductive,
  – cancers
 Air Pollution and Health in Asia:
The Public health and Air Pollution Program
                  (PAPA)
                                The Problem: Air Pollution in Asia:
                              High Levels in Many Cities (2000-2001)
                        400
                                                                                                            SPM Limit = 90 µg/m3 (WHO, 1979)

                        350
                                                                                                        PM10 Limit = 50 µg/m3 (USEPA, 1997)


                        300                                                                                 SO2 Limit = 50 µg/m3 (WHO, 1999)
3
concentration in µg/m




                                                                                                            NO2 Limit = 40 µg/m3 (WHO, 1999)
                        250


                        200


                        150


                        100


                        50


                          0




             Source: Benchmarking Report on Air Quality in Asian cities Stage 2, 2004 (forthcoming)   SO2      NO2     SPM        PM10
Lancet
October,
 2002
         Environmental Burdens
           Premature Deaths
                source: WHO Global Burdon of Disease



Environmental Global    Asian Estimate Asia as a
Risks         Estimate (SEAR+WPR)      percent of
                                       Global
Unsafe Water 1,730,000 730,000         42%
Urban Outdoor 799,000   487,000        61%
Air
Indoor Air    1,619,000 1,025,000      63%
Lead          234,000   88,000         37%
 The Challenge: Expanding current science
base to inform Asian air regulatory decisions
• Air pollution poses clear health effects
• Western research is relevant to Asian populations,
  however extrapolation poses challenges
   – Population characteristics
   – Pollution sources and mixes
• Are observed risks similar?, greater?, smaller?
• A clear need for representative air pollution & health
  studies of local Asian populations
                   PAPA Program
• Partnership with CAI-ASIA to understand the health effects of air
  pollution in Asia, now and in the future

• Active effort underway:
   – Published Scientific Review and Meta Analysis of what is known
      today about health effects in Asian cities
   – Conducting series of epidemiological studies in representative
      Asian cities
       • Understand local impact
       • Combine to provide Asia-wide understanding
   – Publish a Comprehensive Assessment of the state of air pollution
     and health across Asian cities
   – Build capacity of local scientists
• Overall Goal:
   – Quality science to inform key Asian regulatory & policy
     decisions
Health Effects of Outdoor Air Pollution
  in Developing Countries of Asia: A
          Literature Review
                     • Systematic identification of 140
                       peer-reviewed Asian studies
                       1980-2003

                     • Special focus on studies of daily
                       changes in air pollution and
                       health

                     • Conduct first ever Asian meta
                       analysis” quantifying risks,
                       finding initial similarities with
                       West

                     • Identify knowledge gaps to
                       guide future research

                     • Active communication to policy
                       makers
Studies of Air Pollution and Health in Asia 1980–2003
                              Many Health Effects Studied


                    12


                    10
Number of Studies




                                                                                                   TSP
                     8                                                                             PM10
                                                                                                   PM2.5
                     6                                                                             SO2
                                                                                                   NO2
                     4                                                                             CO
                                                                                                   O3
                     2

                     0
                         All-Cause   Respiratory   Cardiovascular   Respiratory   Cardiovascular
                         Mortality    Mortality      Mortality       Hospital        Hospital
                                                                    Admissions     Admissions

                                              Outcome Diagnosis
          Daily Mortality: Initial Results:
        Asian Risk Estimates Similar to West
             Percent Increase in Mortality per 10 micrograms of
                                  Exposure

               0.7
                                                       0.62
               0.6            0.46                                  0.49
               0.5
      Percent 0.4
      Increase 0.3
               0.2
               0.1
                 0
                      US(90 Cities)* Eur(21 Cities)*          Asia (4 Cities)
* Estimates Using Pre-GAM Results (without revision)
          New Research in Asian Cities
• To strengthen base of Asian Health Science:
• Eight new studies of air pollution and health now
  underway in Asian cities
• Acute (short term) effects studies in
     • Bangkok, Hong Kong, Shanghai, Wuhan
     • Strong teams, quality data
• Long Term (chronic) effects
     • Guangzhou, China pilot study in elderly cohort
• New!
• Study teams now identified in India: Chennai; Delhi;
  Ludhiana
             PAPA: Looking Ahead
• A Special Challenge: Understanding the interaction
  among air pollution, poverty, and health
  – In Asia high levels of air pollution, dense population,
    extensive poverty are prevalent
  – Some initial evidence (mostly from West) that the poor
    face worse effects from air pollution
  – Could be due to:
     • Different exposures (roadside, indoor, occupational)
     • Poorer SES\health status (nutrition, medical care) leading to
       higher susceptibility
     • Other factors
  – Potential Public health implications could be significant
• New study under design in Ho Chi Minh City to
  understand poverty effects
                      Conclusions
• Air Pollution from many sources, including vehicles,
  fuels have been shown to have effects on mortality,
  morbidity
• Problem will grow with economic expansion
• WHO estimates place air pollution mortality in hundreds
  of thousands across South Asia, Eastern Mediterranean
  region (including Pakistan)
• While studies are extrapolated from developed world,
  initial PAPA Review and analysis tend to confirm results
  in Asian populations, though many limitations exist
• The PAPA program is building a better base of Asian
  health and air pollution science
   – New studies across Asia, with capacity building as a priority
   – Role of poverty in air pollution to be assessed
                  Conclusions
• Better air monitoring needed over long term
  – To determine current status, monitor ongoing
    progress and assess health, communicate to
    public
• However, Pakistan urban conditions also
  warrant near term action
  –   “Visible emissions” wide-spread
  –   Dense population level, clear exposure
  –   Acute effects commonplace
  –   Provided basis of action in many countries (UK,
      HK, others) before comprehensive monitoring
Thank You!

    Bob O’Keefe
rokeefe @healtheffects.org
www.healtheffects.org