1. Nicholas School of the Environment, Duke University, Durham, North Carolina 27708, United States
2. Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, 4770 Buford Hwy, MSS103-2, Atlanta, Georgia 30341, United States
3. Duke Cancer Institute, Durham, North Carolina 27710, United States
4. Department of Molecular Biomedical Sciences, College of Veterinary Medicine, North Carolina State University, 1060 William Moore Drive, Raleigh, North Carolina 27607, United States
5. Comparative Medicine Institute, North Carolina State University, Raleigh, North Carolina 27607, United States
6. Center for Human Health and the Environment, North Carolina State University, Raleigh, North Carolina 27607, United States