For 33 years, from 1976 to 2010, Ms. Hilgard served as a senior Toxicologist, Risk Assessor, and Technical Review Panelist for the U.S. EPA based in Washington, D.C.  Among many impressive accomplishments during her tenure with the EPA, she developed health and environmental criteria for acceptable fragrance ingredients to be used in commercial cleaning product formulations, published (2013) by EPA under the Green Chemistry Program.  Pat co-chaired the Risk Assessment Training Program, covering such topics as green chemistry and engineering, emerging chemical issues, new and alternative testing methodologies, and the analysis and interpretation of genomic studies for their application in new chemical reviews and determinations, life-cycle accounting and economics related to chemical substitutes and affordability of proposed testing; represented EPA regulatory perspective while serving as an Editor for the Risk Assessment section of the Journal of the Society for Environmental Toxicology and Chemistry (JSETAC).  Other career highlights were her participation in environmental programming of the Woodrow Wilson International Center including the Project on Emerging Nanotechnologies, and with the Wilson Center, US AID, and EPA on issues of China, India, and Africa.