1. TSET Health Promotion Research Center, University of Oklahoma Health Sciences Center, Stephenson Center, Oklahoma City, OK, USA
2. Department of Pediatrics, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
3. Tobacco and Volatiles Branch, Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, GA, USA
4. Division of Public Health, Department of Family and Preventive Medicine, University of Utah School of Medicine and Huntsman Cancer Institute, Salt Lake City, UT, USA