1. Division of Environmental Health, New York, New York, USA
2. Division of Epidemiology, New York City Department of Health and Mental Hygiene, New York, New York, USA
3. Trace Elements Laboratory, Wadsworth Center, New York State Department of Health, Albany, New York, USA
4. Department of Environmental Health Sciences, School of Public Health, University at Albany, State University of New York, Albany, New York, USA