Background: Oxidative potential (OP) has been suggested to be a more health-relevant metric than particulate matter (PM) mass. Land use regression (LUR) models can estimate long-term exposure to air pollution in epidemiological studies, but few have been developed for OP.
Objectives: We aimed to characterize the spatial contrasts of two OP methods and to develop and evaluate LUR models to assess long-term exposure to the OP of PM2.5.
Methods: Three 2-week PM2.5 samples were collected at 10 regional background, 12 urban background, and 18 street sites spread over the Netherlands/Belgium in 1 year and analyzed for OP using electron spin resonance (OPESR) and dithiothreitol (OPDTT). LUR models were developed using temporally adjusted annual averages and a range of land-use and traffic-related GIS variables.
Results: Street/urban background site ratio was 1.2 for OPDTT and 1.4 for OPESR, whereas regional/urban background ratio was 0.8 for both. OPESR correlated moderately with OPDTT ( R 2 = 0.35). The LUR models included estimated regional background OP, local traffic, and large-scale urbanity with explained variance ( R 2) of 0.60 for OPDTT and 0.67 for OPESR. OPDTT and OPESR model predictions were moderately correlated ( R 2 = 0.44). OP model predictions were moderately to highly correlated with predictions from a previously published PM2.5 model ( R 2 = 0.37–0.52), and highly correlated with predictions from previously published models of traffic components ( R 2 > 0.50).
Conclusion: LUR models explained a large fraction of the spatial variation of the two OP metrics. The moderate correlations among the predictions of OPDTT, OPESR, and PM2.5 models offer the potential to investigate which metric is the strongest predictor of health effects.
Citation: Yang A, Wang M, Eeftens M, Beelen R, Dons E, Leseman DL, Brunekreef B, Cassee FR, Janssen NA, Hoek G. 2015. Spatial variation and land use regression modeling of the oxidative potential of fine particles. Environ Health Perspect 123:1187–1192; http://dx.doi.org/10.1289/ehp.1408916
Address correspondence to A. Yang, National Institute for Public Health and the Environment (RIVM), P.O. Box 1, 3720 BA Bilthoven, the Netherlands. Telephone: 31 30 274 3316. E-mail: Aileen.Yang@rivm.nl
We thank K. Meliefste, who was involved in the monitoring campaign.
This study was funded by the RIVM Strategic Research Program (SOR).
The authors declare they have no actual or potential competing financial interests.
Received: 3 July 2014 Accepted: 31 March 2015 Advance Publication: 3 April 2015 Final Publication: 1 November 2015
Note to readers with disabilities: EHP strives to ensure that all journal content is accessible to all readers. However, some figures and Supplemental Material published in EHP articles may not conform to 508 standards due to the complexity of the information being presented. If you need assistance accessing journal content, please contact ehp508@niehs.nih.gov . Our staff will work with you to assess and meet your accessibility needs within 3 working days.
Supplemental Material PDF (777 KB)Note to readers with disabilities: EHP has provided a 508-conformant table of contents summarizing the Supplemental Material for this article (see below) so readers with disabilities may determine whether they wish to access the full, nonconformant Supplemental Material. If you need assistance accessing this or any other content on this site, please contact ehp508@niehs.nih.gov . Our staff will work with you to assess and meet your accessibility needs within 3 working days.
Supplemental Table of Contents PDF (118 KB)