2014 Progress Report: Novel Estimates of Pollutant Mixtures and Pediatric Health in Two Birth CohortsEPA Grant Number: R834799C003
Subproject: this is subproject number 003 , established and managed by the Center Director under grant R834799
(EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).
Center: The Southeastern Center for Air Pollution and Epidemiology: Multiscale Measurements and Modeling of Mixtures
Center Director: Tolbert, Paige
Title: Novel Estimates of Pollutant Mixtures and Pediatric Health in Two Birth Cohorts
Investigators: Strickland, Matthew J , Russell, Armistead G. , Mulholland, James , Waller, Lance , Darrow, Lyndsey , Klein, Mitchel , Guensler, Randy , Davis, Robert , Liu, Yang
Current Investigators: Strickland, Matthew J , Russell, Armistead G. , Chang, Howard , Mulholland, James , Waller, Lance , Darrow, Lyndsey , Klein, Mitchel , Guensler, Randy , Liu, Yang
Institution: Emory University , Georgia Institute of Technology
Current Institution: Emory University , Georgia Institute of Technology , University of Nevada - Reno
EPA Project Officer: Chung, Serena
Project Period: January 1, 2011 through December 31, 2016
Project Period Covered by this Report: October 1, 2013 through September 30,2014
RFA: Clean Air Research Centers (2009) RFA Text | Recipients Lists
Research Category: Health Effects , Air
In utero and early life experiences affect physiological development and can influence sensitivity to environmental factors throughout life. In this Project, we explore the interplay between certain early life events, characterizations of air pollutant mixtures developed as part of the Center’s Mixtures Characterization Toolkit, and a range of pediatric health outcomes using two large, population-based birth cohorts. One cohort consists of roughly 1.7 million Georgia birth records that have been geocoded to the Census block level and linked with pediatric emergency department visits by staff at the Georgia Department of Human Resources. Using this statewide birth cohort, we are investigating acute effects of air pollution mixtures on respiratory health outcomes and ear infections in children, and we are assessing whether children who were born premature or low birth weight are more sensitive to ambient air pollutant concentrations than their counterparts. Further, we are using the statewide birth cohort to investigate whether ambient air pollutant mixtures during pregnancy are associated with the risk of preterm delivery or reduced birth weight. The second birth cohort is comprised of children who were members of the Kaiser Permanente Georgia Health Maintenance Organization in metropolitan Atlanta. In this birth cohort, where comprehensive medical and residential histories are available for each study subject, we will examine whether air pollutant mixtures during the first year of life are associated with the incidence of childhood asthma.
We have made progress in many areas of this project. Some notable accomplishments include:
- We completed time-series epidemiological analysis assessing modification of the acute effect of ambient air pollution on pediatric asthma emergency visits across susceptible subpopulations. This paper (Strickland et al.) is in press at Epidemiology. We found that children born preterm and children born to African American mothers tended to have higher rate ratios than their counterparts. We are presenting these results at the 2014 International Society for Environmental Epidemiology (ISEE) conference.
- We completed the time-series epidemiological analysis of acute effects of ambient air pollution on several different types of respiratory emergency visits among children age 0-4 years. We found several associations. This paper (Darrow et al.) has been accepted by American Journal of Epidemiology. A related manuscript that describes the relationship between emergency visits for bronchiolitis during infancy and subsequent risk of emergency visits for asthma after age five is currently under peer review.
- The paper describing our method for using classification and regression trees to estimate the joint effects of pollutant mixtures (Gass et al.) was published in Environmental Health in April, 2014. A second paper that extends this approach to look at acute associations between air pollutants and pediatric asthma emergency visits in three cities is currently under peer review. We presented the method at the 2014 Society for Epidemiologic Research (SER) conference, and we are presenting both the method and the results of the three-city analysis at the 2014 ISEE conference.
- We completed the Atlanta time-series analyses using the Bayesian ensemble source apportionment estimates. A manuscript based on our results, which includes propagation of air quality model uncertainty through the epidemiological analyses, is currently under peer review.
- The manuscript describing the method for the self-organizing maps (Pearce et al.) was accepted by Environmental Health in June. A poster describing results of an analysis that uses the self-organizing maps in an Atlanta time-series analysis to investigate associations between mixtures and asthma emergency visits will be presented at the 2014 ISEE conference.
- We are working to finish a Georgia-wide analysis of associations between air pollutants and preterm birth using the fused CMAQ estimates. A manuscript is being prepared. Results will be presented at the 2014 ISEE conference.
- At the annual meeting of our external Science Advisory Committee, we presented results of a Georgia-wide analysis of acute effects of PM2.5 estimated from satellite remote sensing on several different respiratory ED visits (including ear infections). We have published the 10-year time-series of satellite-estimated PM2.5 concentrations at 1 km spatial resolution in Atmospheric Chemistry and Physics in June 2014. Although we have not yet generated a manuscript based on these results, it is our intention to do so during the upcoming year. One concern we had was potential confounding by ozone. Now that we have the statewide fused CMAQ results available for ozone we will create two-pollutant models for PM2.5 and ozone. A poster based on this work is being presented at the 2014 ISEE conference.
- Progress is being made on the analysis of incident asthma in the Kaiser Permanente cohort. On the air quality side, the biostatistics core and air quality core are working to downscale the CMAQ estimates to 250-meter grids. These estimates should be available sometime in late 2014. On the health side, we have investigated misclassification of asthma due to different case definitions (a poster based on this work was presented at the 2014 Society for Pediatric Research (SPER) and 2014 SER conferences), and we have also investigated relationships between socioeconomic variables and air quality using the 4-km CMAQ estimates (a poster based on this work will be presented at the 2014 ISEE conference).
- A manuscript to evaluate the potential of adding satellite-detected fire spots to PM2.5 exposure models in Georgia is under peer review for the Journal of Geophysical Research.
We will continue to conduct epidemiologic analyses and produce results-based manuscripts during the upcoming year. Two priority manuscripts are the statewide preterm birth analysis (using the fused CMAQ data) and the statewide emergency visit analysis (that uses the satellite-derived PM2.5 estimates and the fused CMAQ ozone estimates). Currently the Center’s Air Quality Core is developing an approach to incorporate the ROS estimates from Project 1 into the daily source apportionment time-series. During the upcoming year we will use these ROS estimates in a time-series analysis of asthma in Atlanta and prepare a manuscript based on the results.
The Kaiser Permanente analyses will be a major focus moving forward, and once the 250 meter downscaled CMAQ estimates are in hand we will begin using them in the epidemiologic analyses. The health data are ready to analyze, although given the focus on chronic effects (rather than acute effects, on which much of our earlier work has focused) we need to spend some time to ensure these new models are working as intended.
Journal Articles on this Report : 20 Displayed | Download in RIS Format
|Other subproject views:||All 91 publications||39 publications in selected types||All 37 journal articles|
|Other center views:||All 335 publications||137 publications in selected types||All 133 journal articles|
Supplemental Keywords:ambient air, atmosphere, health effects, human health, susceptibility, vulnerability, sensitive populations, infants, children, risk, dose-response, cumulative effects, epidemiology, exposure, public policy, air quality modeling, monitoring, measurement methods, aerosol, particulates, PM2.5, organics, elemental carbon, metals, ozone, oxidants, PAH, sulfates, source characterization, mobile sources, Georgia, GA, Southeast, Health, Scientific Discipline, Health Risk Assessment, Risk Assessments, Biochemistry, Environmental Monitoring, Atmospheric Sciences, children's health, particulate matter, ambient air monitoring, climate change, air pollution, airshed modeling, ambient particle health effects, susceptibility, human health risk
Relevant Websites:Southeastern Center for Air Pollution & Epidemiology (SCAPE) Exit
Progress and Final Reports:Original Abstract
Main Center Abstract and Reports:R834799 The Southeastern Center for Air Pollution and Epidemiology: Multiscale Measurements and Modeling of Mixtures
Subprojects under this Center: (EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).
R834799C001 Development and Deployment of an Instrumentation Suite for Comprehensive Air Quality Characterization Including Aerosol ROS
R834799C002 Examining In-Vehicle Pollution and Oxidative Stress in a Cohort of Daily Commuters
R834799C003 Novel Estimates of Pollutant Mixtures and Pediatric Health in Two Birth Cohorts
R834799C004 A Multi-City Time-Series Study of Pollutant Mixtures and Acute Morbidity