1. US Environmental Protection Agency; Office of Research and Development; National Health and Environmental Effects Research Laboratory; Mid-Continent Ecology Division; Duluth; Minnesota; USA
2. Oak Ridge Institute for Science and Education Research Participation Program; US Environmental Protection Agency; Office of Research and Development; National Health and Environmental Effects Research Laboratory; Mid-Continent Ecology Division; Duluth; Minnesota; USA
3. US Environmental Protection Agency; Office of Research and Development; National Health and Environmental Effects Research Laboratory; Toxicity Assessment Division; Research Triangle Park; North Carolina; USA
4. US Environmental Protection Agency; Office of Research and Development; National Health and Environmental Effects Research Laboratory; Integrated Systems Toxicology Division; Research Triangle Park; North Carolina; USA
5. National Research Council; Duluth; Minnesota; USA