Science Inventory

An Exploratory Analysis of the Relationship Between Ambient Ozone and Particulate Matter Concentrations During Early Pregnancy and Selected Birth Defects in Texas


Vinikoor-Imler, L., T. Stewart, Tom Luben, Allen Davis, AND P. Langlois. An Exploratory Analysis of the Relationship Between Ambient Ozone and Particulate Matter Concentrations During Early Pregnancy and Selected Birth Defects in Texas. ENVIRONMENTAL POLLUTION. Elsevier Science Ltd, New York, NY, 202:1-6, (2015).


This paper provides information on the relationship between PM2.5 and O3 concentrations and birth defects. Few studies have been performed examining air pollution and birth defects. Our study used air data that included women across a large portion of TX and examined co-pollutant models. Most previous studies were only able to examine women living near an air monitoring station and included single-pollutant models. Our study suggests a possible relationship between air pollution concentration during early pregnancy and certain birth defects. Once published, this paper will likely be included in the next PM and O3 ISAs.


Background: Associations between ozone (O3) and fine particulate matter (PM2.5) concentrations and birth outcomes have been previously demonstrated. We perform an exploratory analysis of O3 and PM2.5 concentrations during early pregnancy and multiple types of birth defects. Methods: Data on births were obtained from the Texas Birth Defects Registry and the National Birth Defects Prevention Study (NBDPS) in Texas. Air pollution concentrations were determined using a Bayesian hierarchical model that combined modeled air pollution concentrations with air monitoring data to create bias-corrected concentrations and matched to residential address at birth. Average air pollution concentrations during the first trimester were calculated. Results: The analysis generated hypotheses for future, confirmatory studies; although many of the observed associations between the air pollutants and birth defects were null.
,br>The hypotheses are provided by an observed association between O3 and craniosynostosis [adjusted OR 1.28 (95% CI 1.04, 1.58) per 13.3 ppb increase) and observed inverse associations between PM2.5 concentrations and septal heart defects and obstructive heart defects [adjusted ORs 0.79 (95% CI 0.75, 0.82) and 0.88 (95% CI 0.79, 0.97) per 5.0 µg/m3 increase, respectively] in the Texas Birth Defects Registry study. Septal heart defects and ventricular outflow tract obstructions were also examined using the NBDPS but the associations with PM2.5 were null [adjusted ORs 1.01 (95% CI 0.83, 1.22) and 0.95 (95% CI 0.71, 1.28) per 3.0 µg/m3 increase, respectively].

Both the Texas Birth Defects Registry study and the NBPDS had inverse associations between O3 concentrations and septal heart defects [Texas Birth Defects Registry: adjusted OR 0.89 (95% CI 0.85, 0.93) per 13.3 ppb increase; NBDPS: adjusted OR 0.73 (95% CI 0.57, 0.95) per 13.4 ppb increase]. Conclusions: In this study we explored potential associations between air pollutants and birth defects. Further research to confirm the observed associations for craniosynostosis, septal heart defects, and obstructive heart defects is warranted.

Record Details:

Product Published Date: 03/14/2015
Record Last Revised: 02/07/2019
OMB Category: Other
Record ID: 284677