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 Frank Gilliland,1 Ed Avol,1 Patrick Kinney,2 Michael
Jerrett,1 Timothy Dvonch,3 Frederick Lurmann,4 Timothy
Buckley,5 Patrick Breysse,5 Gerald Keeler,3 Tracy
de Villiers,1 and Rob McConnell1 1Department of Preventive Medicine, Keck School of Medicine, University
of Southern California, Los Angeles, California, USA; 2Mailman School
of Public Health, Columbia University, New York, New York, USA; 3School
of Public Health, University of Michigan, Ann Arbor, Michigan, USA; 4Sonoma
Technology, Inc., Petaluma, California, USA; 5Bloomberg School of
Public Health, Johns Hopkins University, Baltimore, Maryland, USA Abstract 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. Key words: air pollution, airborne, ambient, Centers for Children’s Environmental Health and Disease Prevention Research, Children’s Centers, cohort study, direct measurement, exposure assessment, modeling, National Children’s Study, personal measurement. Environ Health Perspect 113:1447-1454 (2005) . doi:10.1289/ehp.7673 available via http://dx.doi.org/ [Online 24 June 2005] This article is part of the mini-monograph “Lessons Learned from the National Institute of Environmental Health Sciences/U.S. Environmental Protection Agency Centers for Children’s Environmental Health and Disease Prevention Research for the National Children’s Study.” Address correspondence to F. Gilliland, Department of Preventive Medicine, USC Keck School of Medicine, 1540 Alcazar St., CHP 236, Los Angeles, CA 90033 USA. Telephone: (323) 442-1309. Fax: (323) 442-3272. E-mail: gillilan@usc.edu This work was supported by the National Institute of Environmental Health Sciences (ES009581, ES007048, ES009589, ES009600, ES009142, ES009089, ES003819, ES009606, ES10688) , the U.S. Environmental Protection Agency (R826708, R827027, R826724, and R826710) , the National Heart, Lung and Blood Institute (HL61768) , the Hastings Foundation, the Canadian Institutes of Health Research, and the National Children’s Study. The authors declare they have no competing financial interests. Received 12 October 2004 ; accepted 24 March 2005. The full version of this article is available for free in HTML or PDF formats. |