1. College of Veterinary Medicine, Department of Population Health and Pathobiology, North Carolina State University, Raleigh, NC 27606, USA
2. Center for Public Health and Environmental Assessment, Office of Research and Development, United States Environmental Protection Agency, Chapel Hill, NC 27514, USA
3. American Society for the Prevention of Cruelty to Animals, Animal Poison Control Center, Champaign, IL 61820, USA