1. Division of Environmental Health Sciences, School of Public Health, University of California, Berkeley, California, USA
2. Division of Occupational and Environmental Medicine, Department of Medicine, University of California, San Francisco, California, USA
3. Program in Public Health and Planning, Policy and Design, University of California, Irvine, California, USA
4. Division of Epidemiology, School of Public Health, University of California, Berkeley, California, USA
5. Division of General Medicine, Department of Internal Medicine, School of Medicine, University of California, Davis, California, USA
6. Sonoma Technology, Inc., Petaluma, California, USA