Traffic-Related Air Pollution

Transcription

1 Traffic-Related Air Pollution Michael Brauer School of Population and Public Health The University of British Columbia OEMAC 30 th Annual Scientific Conference, October 1-2, 2012 Sheraton Vancouver Wall Centre Hotel, Vancouver, BC

2 LEARNING OBJECTIVES Identify specific health impacts associated with exposure to traffic-related air pollution Describe the magnitude of exposure to traffic related air pollution within the Canadian population Identify approaches to mitigate exposure to traffic-related air pollution

3 *adult cardiopulmonary mortality, lung cancer (not including childhood ARI, birth outcomes) Urban (2002) outdoor air pollution 800,000 deaths (~6000 in Canada) 2/3 in rapidly urbanizing Asia Lopez et al, Lancet, 2006; Brauer et al, 2012

4 Air pollution attributable deaths 8 major Canadian cities City Deaths/yr % chronic % attrib (95% CI) Quebec (5-11) Montreal ( 5-12) Ottawa (4-9) Toronto (6-13) Hamilton (7-4) Windsor (6-12) Calgary (5-11) Metro Van (3-7) Total (5-11) Health Canada,

5 CMA estimates

6 Air pollution and health Air pollution individual risk is small but large exposed population = large population impact no threshold On days with worse air quality, more people die In more polluted cities, people die earlier than in less polluted cities and, in the most polluted areas of cities, there is an increased risk of dying Larrieu et al. Am J Epidemiol,

7 Canadian Census Cohort 2.1 million non-immigrant Canadians (1991 long-form Census 1991) Monitoring data/satellite-based estimates Mean: 8.7 μg/m 3 PM 2.5 Interquartile range: 6.2 μg/m 3 Adjustment for multiple individual-level and contextual covariates Crouse, et al Total (Nonaccidental) IHD Mortality Cardiovascular Cerebrovascular

8 and, in the most polluted areas of cities, there is an increased risk of dying

9 Karner et al. (2010) Environ. Sci. Technol. 44, 5334 Pollution gradients

10 In Metro Vancouver, children living in areas with higher traffic-related air pollution: Increased low birthweight and pre-term birth living <50m from provincial highway: 21% low birthweight Bronchiolitis living <50m from provincial highway: 6% Asthma (early life exposure) 13% of new childhood asthma attributable to traffic Middle ear infections 7% of cases attributable to traffic Traffic-related air pollution Brauer M, et al. Environ Health Perspect. 2008; Clark NA, et al. Environ Health Perspect Karr CJ et al. Am J Resp Crit Care Med 2009; MacIntyre et al. Epidemiology

11 Relative Risk of CHD Mortality Road proximity & cardiovascular death Constant exposure to traffic Moved close to traffic Moved away from traffic X-axis: Non-exposure to traffic m vs > 50 m Highway 150 m vs > 150 m Highway 150 m Highway or 50 m Major Road a 50 m vs > 50 m Major Road Coronary heart disease (CHD) mortality: Black Carbon Gan WQ, Tamburic L, Davies HW, Demers PA, Koehoorn M, Brauer M. Changes in residential proximity to road traffic and the risk of death from coronary heart disease. Epidemiology Sep;21(5):642-9.

12 Pollution gradients WITHIN cities (primarily due to vehicle traffic) linked to health disparities Health Outcome CVD mortality (chronic and acute exposure) CVD morbidity MI onset Atherosclerosis progression Asthma exacerbation Asthma onset Adults Children Lung function decrements (children, chronic exposure) Birth outcomes Allergy Cancer (lung, childhood leukemia) COPD Causality (strength of association) Suggestive, but insufficient Suggestive, but insufficient Suggestive, but insufficient Sufficient Suggestive, but insufficient Sufficient / Suggestive, but insufficient Suggestive, but insufficient Inadequate and insufficient Inadequate and insufficient Inadequate and insufficient Inadequate and insufficient

13 Brauer M, Reynolds C, Hystad P. Report to Health Canada

14 Table 1. Summary of the strength of evidence between exposure to TRAP and health outcomes. Evidence is presented based on the HEI (2010) conclusions (updated with new literature since 2009). A summary of Canadian studies and whether they support the updated HEI conclusion is also presented. Health Outcome Respiratory Strength of Evidence for a Causal Relationship Between TRAP Exposure and Health Effects Update of HEI Review 1 Canadian Literature Selected Canadian References Asthma exacerbation ** Supports Dales et al. (2008); Deger et al. (2010); Sahsuvaroglu et al., 2009; Wang et al. (2010) Respiratory symptoms (non-asthmatic children) Asthma onset - Supports Dales et al. (2009); Karr et al., (2009)Smargiassi et al(2006) Adults: * No Studies No Studies Children: ** Supports Clark et al. (2010); Carlsten et al. (2011) Lung function * Supports Dales et al. (2008); Cakmak et al. (2011) COPD - No Studies No Studies Allergy - No Studies No Studies Cardiovascular CVD mortality * Supports Gan et al., 2011; Jerrett et al. (2009) MI onset * No Studies No Studies Atherosclerosis * No Studies No Studies Cancer Lung cancer * Supports Band et al. (2011) Hystad et al. (Submitted, 2012) Other (non-lung) cancer - Supports Crouse et al. (2010) Childhood cancer - No Studies No Studies Pregnancy/Birth Outcomes - Supports Brauer et al., (2008); Genereux et al., (2008) All Cause Mortality - Supports Jerrett et al. (2009) 1 ** Sufficient evidence to infer a causal association; * Suggestive but not sufficient evidence to infer a causal association; - Inadequate and insufficient evidence to infer the presence or absence of a causal association (Criteria for strength of casual inference based on the HEI (2010)).

15 META ANALYSIS II Anderson et al., Long-term exposure to air pollution and the incidence of asthma: metaanalysis of cohort studies. Air Qual Atmos Health The results are consistent with an effect of outdoor air pollution on asthma incidence. NO 2 PM

16 Environ Health Perspect 117: (2009) How often do trucks pass through the street where you live, on weekdays? Never/seldom/frequently through the day/almost the whole day 16

17 McIntyre et al, In preparation 2012 Traffic pollution, Asthma Genetics (TAG) Main (NO 2 ) effects Genetically stratified effects (pooled analysis) N=7787

18 Adults from 13 cities (ECRHS II) Adult onset asthma No associations between NO 2 and asthma for any genotypes of GSTM1, GSTT1, GSTP1, TLR4, and ADRB2 genes C/C carriers (wild type) NQO1 rs G/C or G/G carriers Castro-Giner F, et al. Traffic-related air pollution, oxidative stress genes, and asthma (ECHRS). Environ Health Perspect Dec;117(12):

19 Henderson et al. 2007; Brauer et al. 2012; Amram et al Traffic proximity N Legend Freeways Major Roads Annual NO (ppb) Traffic influence zones (<500m from highway or <100m from major road) 32% of Canadian population 36% of primary schools in large Canadian cities

20 Number of individuals, by province, living within 500m of a highway or 100m of a major road Province Population Exposed Alberta 905,280 (27%) British Columbia 1,502,500 (37%) Manitoba 311,480 (27%) New Brunswick 214,080 (29%) Newfoundland 89,500 (18%) Northwest Territories 4,130 (10%) Nova Scotia 304,030 (33%) Ontario 3,066,710 (25%) Prince Edward Island 53,130 (39%) Québec 3,184,430 (42%) Saskatchewan 404,870 (42%) Yukon Territory 7,770 (26%) Canada 10,047,910 (32%)

21 Table 2. Summary of potential policy options for reducing TRAP exposures differentiated according to their temporal and spatial exposure reduction outcomes. Uniform Exposure Reduction Modify Existing Structures (short-term time horizon) Target high emitting vehicles for retrofit or removal with inspection and maintenance programs 1 Implement traffic congestion reduction policies Guide New Development (long-term time horizon) Conduct integrated land-use planning that incorporates health impact assessments Continue to implement low emission vehicle standards for new vehicles 1 Expansion of electric vehicle charging infrastructure Spatially Targeted Exposure Reduction Limit heavy truck traffic to specific routes and times Implement targeted traffic congestion reduction policies Install HVAC filter systems in buildings that house vulnerable populations within 150m from busy roads (>15,000 AADT) Separate active commuting from busy roads (e.g. create bicycle routes on minor roads) Implement anti-idling and low emission zones Site new buildings that will house vulnerable populations (e.g. schools, daycares, retirement homes) 150m from busy roads (15,000 AADT) Conduct integrated land-use planning that incorporates local health impact assessments 1 Inspection and maintenance programs exist in many parts of Canada and increasingly stringent vehicle emissions standards have been implemented nationally. Brauer M, Reynolds C, Hystad P. Report to Health Canada

22 E-Z pass and premature birth Reductions in traffic congestion generated by E-Z Pass reduced incidence of prematurity (10.8%) and low birth (11.8%) among mothers within 2km of a toll plaza Currie J, Walker R. TRAFFIC CONGESTION AND INFANT HEALTH: EVIDENCE FROM E-ZPASS. Working Paper NATIONAL BUREAU OF ECONOMIC RESEARCH

23 Healthy urban design Separate major roadways from people (air, noise, accidents) Infrastructure to promote active transport 23

24 Munich Petuelpark

25 A way forward? Health disparities associated with SPATIAL air pollution variability within populated areas Interventions lead to health benefits Opportunities to link with other built environment initiatives (physical activity, climate change) to improve population health Giles L et al. Environmental Health Perspectives, (1):

26 Thank you!