Funding for this research was provided by:
National Institute of Environmental Health Sciences (1P20ES018173, 5R01ES020926, 3R01ES020926)
Environmental Protection Agency (RD-83459601-0))
Austin Family Foundation
Received: 9 August 2017
Accepted: 12 December 2017
First Online: 5 January 2018
Ethics approval and consent to participate
: All methods and procedures were approved by the Stanford University Institutional Review Board for the Protection of Human Subjects. Written informed consent was received from parents of subjects prior to inclusion in the study.
: Not applicable
: The authors declare that they have no competing interests.
: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.