1. Environmental Defense Fund, New York, New York, USA
2. Department of Population Health Sciences, Virginia Polytechnic Institute and State University, Blacksburg, Virginia, USA
3. Department of Environmental and Occupational Health, George Washington University, Washington, District of Columbia, USA
4. Department of Civil and Environmental Engineering and School of Public Health, University of California, Berkeley, California, USA
5. Department of Environmental Sciences, University of Virginia, Charlottesville, Virginia, USA
6. Department of Civil and Environmental Engineering, University of Washington, Seattle, Washington, USA
7. Department of Civil and Environmental Engineering, University of California, Los Angeles, Los Angeles, California, USA