Dataset Information

Creating national air pollution models for population exposure assessment in Canada.

ABSTRACT:

Background

Population exposure assessment methods that capture local-scale pollutant variability are needed for large-scale epidemiological studies and surveillance, policy, and regulatory purposes. Currently, such exposure methods are limited.

Methods

We created 2006 national pollutant models for fine particulate matter [PM with aerodynamic diameter ? 2.5 ?m (PM2.5)], nitrogen dioxide (NO2), benzene, ethylbenzene, and 1,3-butadiene from routinely collected fixed-site monitoring data in Canada. In multiple regression models, we incorporated satellite estimates and geographic predictor variables to capture background and regional pollutant variation and used deterministic gradients to capture local-scale variation. The national NO2 and benzene models are evaluated with independent measurements from previous land use regression models that were conducted in seven Canadian cities. National models are applied to census block-face points, each of which represents the location of approximately 89 individuals, to produce estimates of population exposure.

Results

The national NO2 model explained 73% of the variability in fixed-site monitor concentrations, PM2.5 46%, benzene 62%, ethylbenzene 67%, and 1,3-butadiene 68%. The NO2 model predicted, on average, 43% of the within-city variability in the independent NO2 data compared with 18% when using inverse distance weighting of fixed-site monitoring data. Benzene models performed poorly in predicting within-city benzene variability. Based on our national models, we estimated Canadian ambient annual average population-weighted exposures (in micrograms per cubic meter) of 8.39 for PM2.5, 23.37 for NO2, 1.04 for benzene, 0.63 for ethylbenzene, and 0.09 for 1,3-butadiene.

Conclusions

The national pollutant models created here improve exposure assessment compared with traditional monitor-based approaches by capturing both regional and local-scale pollution variation. Applying national models to routinely collected population location data can extend land use modeling techniques to population exposure assessment and to informing surveillance, policy, and regulation.

SUBMITTER: Hystad P

PROVIDER: S-EPMC3237350 | biostudies-literature | 2011 Aug

REPOSITORIES: biostudies-literature

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Publications

Creating national air pollution models for population exposure assessment in Canada.

Hystad Perry P Setton Eleanor E Cervantes Alejandro A Poplawski Karla K Deschenes Steeve S Brauer Michael M van Donkelaar Aaron A Lamsal Lok L Martin Randall R Jerrett Michael M Demers Paul P

Environmental health perspectives 20110331 8

<h4>Background</h4>Population exposure assessment methods that capture local-scale pollutant variability are needed for large-scale epidemiological studies and surveillance, policy, and regulatory purposes. Currently, such exposure methods are limited.<h4>Methods</h4>We created 2006 national pollutant models for fine particulate matter [PM with aerodynamic diameter ≤ 2.5 μm (PM2.5)], nitrogen dioxide (NO2), benzene, ethylbenzene, and 1,3-butadiene from routinely collected fixed-site monitoring d ...[more]

PMID: 21454147

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Dataset Information

Creating national air pollution models for population exposure assessment in Canada.

Background

Methods

Results

Conclusions

Publications

Creating national air pollution models for population exposure assessment in Canada.

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