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Dr. Daniel T. Chang
RESEARCH PHYSICAL SCIENTIST
Exposure & Dose Research Branch
Human Exposure & Atmospheric Sciences Division
EDUCATION/TRAINING
Ph.D. in Chemical Physics, 2002, Texas Tech University
M.S. in Chemical Physics, 1999, Texas Tech University
B.A. in Chemistry, 1993, Rice University
PROFESSIONAL EXPERIENCE
Research Physical Scientist, USEPA, ORD, NERL-HEASD, Las Vegas, NV 2007 to present.
Postdoctoral Fellow, USEPA, ORD, NERL-HEASD, Las Vegas, NV 2005 to 2007.
Postdoctoral Fellow, Pacific Northwest National Laboratory, Richland, WA 2003 to 2005.
SELECTED AWARDS AND HONORS
U.S. EPA\ORD Technical Assistance Award: PBPK Modeling Team, 2007.
SELECTED PUBLICATIONS (6 out of 8 from 2002 to present)
M.-R. Goldsmith, D.T. Chang, R. Tornero-Velez, S. Little, M. Pasquinelli, J. Rabinowitz, and C.C. Dary. A Consensus Docking Study on the Stereoselectivity of Pyrethroid-like Compounds in Carboxylesterase (in preparation).
D.T. Chang, R. Tornero-Velez, M.S. Okino, C.S. Mazur, J.F. Kenneke, F.W. Power, J.B. Knaak, M.E. Dellarco and C.C. Dary. A Dermal Physiologically Based Pharmacokinetic/Pharmacodynamic (PBPK/PD) Model for Propiconazole Using the Exposure Dose Estimating Model (ERDEM) (in preparation).
D.T. Chang, G.K. Schenter and B.C. Garrett. Self-consistent Polarization NDDO: Application to Neutral Water Clusters (submitted to Journal of Chemical Physics).
D.T. Chang, G.K. Schenter and B.C. Garrett. 2004. Chemical Fate of Contaminants in the Environment: Chlorinated Hydrocarbons in the Groundwater, Pacific Northwest National Laboratory Grand Challenge 5, FY04 Highlight 3.
D.T. Chang and G.I. Gellene. 2003. An Ab Initio, Analytically Fitted, Global Potential Energy Surface for the Ground Electronic State of He3+. Journal of Chemical Physics, 119, 4694.
D.T. Chang, K. Reimann, G. Surratt, G.I. Gellene, P. Lin and R.R. Lucchesse. 2002. First Principles Determination of the Photoelectron Spectrum of LiH–. Journal of Chemical Physics, 117, 5757.
SELECTED PRESENTATIONS (6 out of 11 from 2004 to present)
D.T. Chang, M.-R. Goldsmith, R. Tornero-Velez, R. Rabinowitz and C.C. Dary. 2007. Utilizing In Silico Techniques to Elucidate the Stereoselective Behaviour of Pyrethroids within Carboxylesterase. 234th ACS National Meeting, Modern Chiral Agrochemicals: the Importance of Enantioselectivity in Fate and Effects Symposium, Boston, MA (invited).
D.T. Chang, T.L. Whitehead, M.S. Okino, J.F. Kenneke, C.S. Mazur, R. Tornero-Velez, J. Johnson and C.C. Dary. 2006. An In Silico Investigation of the Enantioselective Metabolism Rates of Triazole Fungicides, 14th Annual North American International Society for the Study of Xenobiotics Meeting, Rio Grande, Puerto Rico.
D.T. Chang, P.P. Egeghy, J.B. Knaak, R. Tornero-Velez, M.S. Okino, F.W. Power, M.E. Dellarco, C.S. Mazur, J.F. Kenneke and C.C. Dary. 2006. Influence of Matrix Formulation on Dermal Percutaneous Absorption of Triazole Fungicides Using QSAR and PBPK/PD Models, International Society of Enviromental Epidemiology/International Society of Exposure Analysis International Conference on Environmental Epidemiology and Exposure, Paris, France.
J.B. Knaak, D.T. Chang, C.C. Dary, R. Tornero-Velez, M.S. Okino and F.W. Power. 2005. Estimation of Adipose Tissue:Blood Partition Coefficients of Carbamates and Organophosphorous (OP) Pesticides Using Relative Lipid Content and LogP as the Mechanistic Determinants, 230th ACS National Meeting, Washington, DC.
D.T. Chang. 2005. Understanding Solvent Effects within Approximate Molecular Orbital Theory, California State University – Long Beach, Long Beach, CA (invited).
D.T. Chang, G.K. Schenter and B.C. Garrett. 2004. Self-consistent Polarization NDDO: Application to Neutral and Ionic Water Clusters, 227th ACS National Meeting, MJS Dewar Memorial Symposium, Anaheim, CA.
NARRATIVE
My expertise is in the development and application of computational chemistry methods as they pertain to exposure assessment. I am interested in the application of high-level computational chemistry methods (quantitative structure-activity relationships, molecular dynamics, docking, variational transition-state theory, ab initio and semiempirical molecular orbital theory calculations) towards estimating unknown chemical-specific parameters utilized within physiologically based pharmacokinetic/pharmacodynamic (PBPK/PD) models. Current projects are focused on the application and development of models to estimate and elucidate partitioning and transport across physiological barriers, enzymatic metabolism (serine esterases and cytochrome P450’s), and elimination of xenobiotics in the context of PBPK/PD models. Previous research includes chemical kinetics, solvation theory, development of hybrid classical/quantum mechanical methods to study condensed phase dynamics, and understanding the chemical fate of environmental contaminants.