ASSESSMENT OF IMPACTS OF AIR POLLUTION ON HEALTH Michal Krzyzanowski WHO ECEH Bonn Office 1
Exposure - Response Population X Exposure IMPACT ESTIMATE FOR POPULATION X Population X health status WHO Air Quality Guidelines for Europe Second edition WHO Regional Publications, European Series, No 91 WHO Copenhagen, 2000 Background material: wwwwhonl CD-Rom 2
WHO Air Quality Guidelines, 2 nd edition Particulate matter (PM10 or PM25) Available information does not allow a judgement to be made of concentrations below which no effects would be expected response Use risk estimates for standard setting exposure WHO -AQG 2 nd ed Effect estimates of long-term exposure to PM associated with a 10 µg/m 3 increase in the annual mean concentration Endpoint Death (1) Death (2) Bronchitis (3) FEV1, in children (4) FEV1 in adults (5) PM25 RR (95%CI) 114 (104 124) 107 (104 111) 134 (094-199) % change (95% CI) -19% (-31 - -06) PM10 110 (103 118) 1,29 (096-183) -12% (-23 - -01) -10 (NA) 1 Dockery et al, 1993; 2 Pope et al, 1995; 3 Dockery et al, 1996; 4 Raizenne et al 1996; 5 Ackermann-Liebrich et al, 1997 3
WHO AQG 2 nd ed Health effect estimates per 10 mg/m3 increase in 24-h mean PM 25 or PM10 concentrations RR and 95%CI Endpoint Bronchodialator use Cough Lower resp symptoms Change in PEFR Hospital admissions, respir Diseases Death PM25 1015 (1011 1019) PM10 103 (102 104) 104 (102 105) 103 (102 105) -013% (-017 - -009) 1008 (1005 1011) 1007 (1006 1009) 4
Assessment of exposure to air pollution Monitoring ambient air quality for health impact assessment WHO Regional Publications, European Series No 85 WHO Copenhagen 1999 5
Health Impact Assessment of Air Pollution in the WHO European Region 30 Countries 141 Cities Estimated health impacts of ambient air pollution in Europe, mid-1990s (1 of 2) Exposure indicator Health indicator / population at risk AP # cases (x1000) PM10, long term Mortality, urban, age>35 4% - 13% 102-368 PM10, daily levels Daily number of deaths, urban 14% - 32% 41 89 SO2, daily levels Daily number of deaths, urban 04% - 07% 12 20 Ozone, 8-h mean > 110 ìg/m3 Daily number of deaths, all popul In 15 EU countries 01% - 0,2% 2-4 6
Estimated health impacts of ambient air pollution in Europe, mid-1990s (2 of 2) Exposure indicator Health indicator / population at risk AP # cases (x1000) PM10, daily levels Hospital admissions for respiratory diseases, urban 15% - 34% 7-16 SO2, daily levels Ozone, 8-h mean > 110 ìg/m3 Hospital admissions for asthma, age <15 years, urban Hospital admissions for respiratory diseases, all popul age > 15 years in 15 EU countries 07% 34% 01% - 03% 02 10 03 10 Frequency distribution of health risk expressed as population exposure to secondary PM10 from LRTAP in 1996 (5 th, 25 th, 75 th and 95 th percentile) 1990 1996 Source: TFH 1999 7
Annual number of premature deaths (in thousands) associated with long-term exposure to PM from longrange transport of air pollution in 760 million of people in Europe Particulates Primary Central estimate 43 Range 22 86 Secondary (NO4, SO4, NO3) Total 148 191 74 295 95-382 Source: TFH 1999 WHO WG «Quantification of the health effects of exposure to air pollution» RECOMMENDATION 1 (OF 8) The most complete estimates of attributable numbers of deaths and average reductions in life-span are those based on cohort studies Critical research need: confirmation of transferability of US cohort studies to Europe and in other regions 8
WHO WG «Quantification of the health effects of exposure to air pollution» RECOMMENDATION 2 Time-series studies are likely to provide: lower bound of effect in studies on mortality; estimates with lower measurement error and potential confounding relative to the cohort studies Additional merits of TS studies WHO WG «Quantification of the health effects of exposure to air pollution» RECOMMENDATION 5 Health impact assessments should exercise great care when the evidentiary and target populations differ In general, the most precise, valid and specific effect estimate should be used for impact assessment Use sensitivity analysis to assess the possible impact of the difference in the populations 9
WHO Comparative Risk Assessment project Amr regions Amr A Canada, Cuba, United States of America Amr B Antigua and Barbuda, Argentina, Bahamas, Barbados, Belize, Brazil, Chile, Colombia, Costa Rica, Dominica, Dominican Republic, El Salvador, Grenada, Guyana, Honduras, Jamaica, Mexico, Panama, Paraguay, Saint Kitts and Nevis, Saint Lucia, Saint Vincent and the Grenadines, Suriname, Trinidad and Tobago, Uruguay, Venezuela Amr D Bolivia, Ecuador, Guatemala, Haiti, Nicaragua, Peru CONCLUSIONS Significant number of deaths and other health problems is attributable to air pollution Action to reduce air pollution must focus on population exposure and use health impact assessment to select priorities Estimation of the impacts requires combination of research and (health & environment) monitoring data 10
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