1. Pulmonary and Critical Care Medicine Section, VA Boston Healthcare System, Boston, Massachusetts, USA
2. Channing Division of Network Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts, USA
3. Exposure, Epidemiology and Risk Program, Department of Environmental Health, Harvard School of Public Health, Boston, Massachusetts, USA
4. Department of Epidemiology, Harvard School of Public Health, Boston, Massachusetts, USA
5. Department of Urban and Environmental Policy and Planning, Tufts University, Medford, Massachusetts, USA
6. Environmental and Occupational Medicine and Epidemiology Program, Department of Environmental Health, Harvard School of Public Health, Boston, Massachusetts, USA
7. Environmental Health Sciences Division, School of Public Health, University of California, Berkeley, California, USA