Dr. Gibb has a Ph.D. (epidemiology, Johns Hopkins). He has testified before federal and state courts, an international tribunal, and the U.S. Senate. Before
starting Gibb Epidemiology, he was President of Tetra Tech Sciences, a health risk assessment company. Dr. Gibb was Associate Director for Health at the National Center for Environmental Assessment of U.S. EPA where he oversaw the Agency’s Integrated Risk Information System (IRIS) and directed EPA’s assessment of health risks resulting from the collapse of the World Trade Center Towers. He co-authored EPA’s Guidelines for Carcinogen Risk Assessment and EPA’s Risk Assessment Principles and Practices. He received EPA’s Gold Medal for his work on arsenic in drinking water. His mortality study of chromate workers formed the basis of OSHA’s Permissible Exposure Limit on Hexavalent Chromium. He is an author of the World Health Organization’s Principles for the Assessment of Risks to Human Health from Exposure to Chemicals.