Air pollution exposure assessment for epidemiologic studies of pregnant women and children: lessons learned from the Centers for Children's Environmental Health and Disease Prevention Research.
The National Children's Study is considering a wide spectrum of airborne pollutants that are hypothesized to potentially influence pregnancy outcomes, neurodevelopment, asthma, atopy, immune development, obesity, and pubertal development. In this article we summarize six applicable exposure assessment lessons learned from the Centers for Children's Environmental Health and Disease Prevention Research that may enhance the National Children's Study: a) Selecting individual study subjects with a wide range of pollution exposure profiles maximizes spatial-scale exposure contrasts for key pollutants of study interest. b) In studies with large sample sizes, long duration, and diverse outcomes and exposures, exposure assessment efforts should rely on modeling to provide estimates for the entire cohort, supported by subject-derived questionnaire data. c) Assessment of some exposures of interest requires individual measurements of exposures using snapshots of personal and microenvironmental exposures over short periods and/or in selected microenvironments. d) Understanding issues of spatial-temporal correlations of air pollutants, the surrogacy of specific pollutants for components of the complex mixture, and the exposure misclassification inherent in exposure estimates is critical in analysis and interpretation. e) "Usual" temporal, spatial, and physical patterns of activity can be used as modifiers of the exposure/outcome relationships. f) Biomarkers of exposure are useful for evaluation of specific exposures that have multiple routes of exposure. If these lessons are applied, the National Children's Study offers a unique opportunity to assess the adverse effects of air pollution on interrelated health outcomes during the critical early life period.
Gilliland
Frank
F
Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles, California, USA.
Avol
Ed
E
Kinney
Patrick
P
Jerrett
Michael
M
Dvonch
Timothy
T
Lurmann
Frederick
F
Buckley
Timothy
T
Breysse
Patrick
P
Keeler
Gerald
G
de Villiers
Tracy
T
McConnell
Rob
R
D000393:Air Pollutants / Q000633:toxicity*; D002648:Child; D002669:Child Welfare; D004781:Environmental Exposure; D004782:Environmental Health; D005260:Female; D006801:Humans; D011247:Pregnancy; D011256:Pregnancy Outcome; D011315:Preventive Medicine; D014481:United States
D000393:Air Pollutants