1. Department of Soil, Water, and Environmental Sciences, Yuma Agricultural Center, The University of Arizona, Yuma, Arizona 85364, National Center for Environmental Health, Centers for Disease Control and Prevention (CDC), Atlanta, Georgia 30341, Department of Environmental Sciences, University of California, Riverside, Riverside, California 92521, and Personal Chemical Exposure Program, Department of Entomology, University of California, Riverside, Riverside, California 92521