1. US Environmental Protection Agency; Office of Research and Development, National Health and Environmental Effects Research Laboratory; Narragansett Rhode Island
2. US Environmental Protection Agency; Office of Research and Development, Safe and Sustainable Water Resources Research Program; Research Triangle Park North Carolina
3. University of Maryland; Center for Environmental Science; Solomons Maryland
4. US Environmental Protection Agency, Office of Research and Development; National Health and Environmental Effects Research Laboratory; Research Triangle Park North Carolina