1. Exposure, Epidemiology and Risk Program, Harvard School of Public Health, Boston, Massachusetts, USA
2. Department of Work Environment, University of Massachusetts Lowell, Lowell, Massachusetts, USA
3. Department of Dermatology, Yale University School of Medicine, New Haven, Connecticut, USA
4. Division of Applied Research and Technology, National Institute for Occupational Safety and Health, Cincinnati, Ohio, USA
5. Occupational and Environmental Medicine Program, Yale University School of Medicine, New Haven, Connecticut, USA