Residential particulate matter, proximity to major roads, traffic density and traffic volume as risk factors for preterm birth in California

Jean M Costello; Martina A Steurer; Rebecca J Baer; John S Witte; Laura L Jelliffe-Pawlowski

doi:10.1111/ppe.12820

Residential particulate matter, proximity to major roads, traffic density and traffic volume as risk factors for preterm birth in California

Paediatr Perinat Epidemiol. 2022 Jan;36(1):70-79. doi: 10.1111/ppe.12820. Epub 2021 Nov 19.

Authors

Jean M Costello^{1

2}, Martina A Steurer^{1

3

4}, Rebecca J Baer^{1

5}, John S Witte^{4

6

7}, Laura L Jelliffe-Pawlowski^{1

4}

Affiliations

¹ California Preterm Birth Initiative, University of California San Francisco, San Francisco, CA, USA.
² Program in Biological and Medical Informatics, University of California San Francisco, San Francisco, CA, USA.
³ Department of Paediatrics, University of California San Francisco, San Francisco, CA, USA.
⁴ Department of Epidemiology and Biostatistics, University of California San Francisco, San Francisco, CA, USA.
⁵ Department of Paediatrics, University of California San Diego, San Francisco, CA, USA.
⁶ Department of Epidemiology & Population Health, Stanford University, Stanford, CA, USA.
⁷ Department of Biology, Stanford University, Stanford, CA, USA.

PMID: 34797570
DOI: 10.1111/ppe.12820

Abstract

Background: While pollution from vehicle sources is an established risk factor for preterm birth, it is unclear whether distance of residence to the nearest major road or related measures like major road density represent useful measures for characterising risk.

Objective: To determine whether major road proximity measures (including distance to major road, major road density and traffic volume) are more useful risk factors for preterm birth than other established vehicle-related measures (including particulate matter <2.5 μm in diameter (PM_2.5 ) and diesel particulate matter (diesel PM)).

Methods: This retrospective cohort study included 2.7 million births across the state of California from 2011-2017; each address at delivery was geocoded. Geocoding was used to calculate distance to the nearest major road, major road density within a 500 m radius and major road density weighted by truck volume. We measured associations with preterm birth using risk ratios adjusted for target demographic, clinical, socioeconomic and environmental covariates (aRRs). We compared these to the associations between preterm birth and PM_2.5 and diesel PM by census tract of residence.

Results: Findings showed that whereas higher mean levels of PM_2.5 and diesel PM by census tract were associated with a higher risk of preterm birth, living closer to roads or living in higher traffic density areas was not associated with higher risk. Residence in a census tract with a mean PM_2.5 in the top quartile compared with the lowest quartile was associated with the highest observed risk of preterm birth (aRR 1.04, 95% CI 1.04, 1.05).

Conclusions: Over a large geographical region with a diverse population, PM2.5 and diesel PM were associated with preterm birth, while measures of distance to major road were not, suggesting that these distance measures do not serve as a proxy for measures of particulate matter in the context of preterm birth.

Keywords: air pollution; particulate matter; preterm birth; road proximity; traffic.

MeSH terms

Air Pollutants* / adverse effects
Air Pollutants* / analysis
Air Pollution* / adverse effects
Air Pollution* / analysis
California / epidemiology
Census Tract
Humans
Infant, Newborn
Particulate Matter / adverse effects
Particulate Matter / analysis
Premature Birth* / epidemiology
Premature Birth* / etiology
Retrospective Studies
Risk Factors
Vehicle Emissions / toxicity

Substances

Air Pollutants
Particulate Matter
Vehicle Emissions

Grants and funding

California Preterm Birth Initiative