Claudio Sorrentino is the Senior Toxicologist and Chief of the Northern California Unit of the Human and Ecological Risk Office, Department of Toxic Substances Control (DTSC), California Environmental Protection Agency in Sacramento. He joined DTSC in December 2007. His work includes providing scientific and technical advice to various programs within DTSC and to other agencies on risk assessment, exposure assessment, and toxicological issues. He also reviews and refines evaluations of complex sampling and analysis plans, risk assessments, and detailed biological effects studies, applying and integrating scientific, toxicologic and ecologic principles to site specific hazardous substance releases. He provides guidance in preparing more complex exposure assessments, risk assessments, and studies to evaluate the human health impacts of hazardous substance releases into the environment to determine what appropriate remedial alternatives or permit conditions are necessary. Claudio has been a member of the Environmental Molecular Diagnostic team since its formation. He graduated from the School of Pharmacy of the University of Rome (Italy) “La Sapienza” in 1989 and earned a Master in Pharmacology in 1995 from School of Medicine of the same university. He earned a Ph.D. in Environmental Health Sciences from the New York University in New York, NY in 2004 for his work on the molecular and organismic effect of co-exposure to metals and aromatic hydrocarbons in fish from the Hudson River, NY. From 2004 to 2007, he was a postdoctoral scholar performing research on the molecular mechanisms of dioxins and dioxin-like chemicals in M.S. Denison’s Lab at UC Davis. In 2006, he was the instructor in charge of teaching “Introduction to Environmental Toxicology” at UC Davis. Claudio is a full member of the Society of Toxicology and is a reviewer for the journal Chemico-Biological Interactions.