Raymond S. H. Yang, Ph.D.
Professor Emeritus

Phone: (970) 491-7038
Fax: (970) 491-2940
Email: Raymond.Yang@colostate.edu

Degrees

Research Interests

Dr. Yang's research interests are Physiologically Based Pharmacokinetic/Pharmacodynamic (PBPK/PD) Modeling, Biologically Based Dose Response (BBDR) Modeling, Reaction Network Modeling, Chemical Mixture Toxicology, Toxicologic Interactions, Carcinogenesis/ Neuro-Developmental Toxicology, Risk Assessment.

Dr. Yang has had extensive experience in toxicology in industry (Mellon Institute/Union Carbide Corporation), government (National Institute of Environmental Health Sciences/National Toxicology Program; USEPA/National Center for Environmental Assessment), and academia (Cornell University, Albany Medical College, CSU). He established and developed the Quantitative and Computational Toxicology Group at CSU. Dr. Yang believes that the application of computer to toxicology, just as computer applications in our life, will become more and more prevalent. Thus, the development of Virtual Cells, Virtual Organs, Virtual Animals, and Virtual Humans is only the matter of time. In that sense, the CSU Quantitative and Computational Toxicology Group is at the beginning of establishing a new form of "bioinformatics" in that they are building the pieces of the puzzle on the complex biological processes involved in toxicology.

Selected Publications

• Thomas, R. S., Conolly, R.B., Gustafson, D.L., Long, M.E., Benjamin, S.A., and Yang, R. S. H. 2000. A physiologically-based pharmacodynamic analysis of hepatic foci within a medium-term liver foci bioassay using pentachlorobenzene as a promotor and diethylnitrosamine as an initiator. Toxicol. Appl. Pharmacol. 166:128-137.
• Ou, Y.C., Connolly, R.B., Thomas, R.S., Xu, Y., Andersen, M.E., Chubb, L., Pitot, H.C., and Yang, R. S. H. 2001. A clonal growth model: Time-course simulations of liver foci growth following penta or hexachlorobenzene treatment in a medium-term bioassay. Cancer Res. 61: 1879-89.
• Lee, S. K., Ou, Y. C., and Yang, R. S. H. 2002. Comparison of Pharmacokinetic Interactions and Physiologically-based Pharmacokinetic Modeling of PCB 153 and PCB 126 in Non-pregnant, Lactating Mice and Suckling Pups Toxicol. Sci. 65:26-34.
• Dobrev, I., Andersen, M. E., and Yang, R. S. H. 2002. In silico toxicology: Simulating interaction thresholds for human exposure to mixtures of trichloroethylene, tetrachloroethylene, and 1,1,1-trichloroethane. Environ. Health Perspect. 110:1031-1039.
• Bae, D. S., Hanneman, W. H., Yang, R. S. H., and Campain, J. A. 2002. Characterization of gene expression changes associated with MNNG, arsenic, or metal mixture treatment in human keratinocytes: Application of cDNA microarray technology. Environ. Health Perspect. 110 (Supplement 6):931-941.
• Liao, K. H., Dobrev, I., Dennison, Jr., J. E., Andersen, M. E., Reisfeld, B., Reardon, K. F., Campain, J. A., Wei, W., Klein, M. T., Quann, R. J., Yang, R. S. H. 2002. Application of biologically based computer modeling to simple or complex mixtures. Environ. Health Perspect. 110 (Supplement 6):957-963.
• Dennison, J. E., Andersen, M.E., and Yang, R.S.H. 2003. Characterization of the pharmacokinetics of gasoline using PBPK modeling with a complex mixture chemical lumping approach. Inhalation Toxicol. 15:961-968.
• Perez, D. S., Fox, M., Yang, R. S. H., and Campain, J. A. 2003. Arsenic and benzo[a]pyrene differentially alter the capacity for differentiation and growth properties of primary human epidermal keratinocytes. Toxicol. Sci. 76: 280-90.
• Yang, R. S. H., El-Masri, H. A., Thomas, R. S., Dobrev, I., Dennison, Jr., J. E., Bae, D. S., Campain, J. A., Liao, K. H., Reisfeld, B., Andersen, M. E., Mumtaz, M. M. 2004. Chemical mixture toxicology: from descriptive to mechanistic, and going on to in silico toxicology. Environ. Toxicol. Pharmacol. 18:65-81.
• Dennison, J. E., Andersen, M. E., Clewell, H. J., and Yang, R. S. H. 2004. Development of a PBPK model for volatile fractions of gasoline using chemical lumping analyses. Environ. Sci. Tech. 38:5674-5681.
• Reddy, M., Yang, R. S. H., Clewell III, H. J., and Andersen, M. E. 2005. Physiologically Based Pharmacokinetics: Science and Applications, John Wiley & Sons, 420 pp.
• Mayeno, A. N., Yang, R. S. H., and Reisfeld, B. 2005. Biochemical Reaction Network Modeling: A New Tool for Predicting Metabolism of Chemical Mixtures. Environ. Sci. Tech. 39:5363-5371.
• Lu, Y., Lohitnavy, M., Reddy, M. B., Lohitnavy, O., and Yang, R. S. H. 2006. An updated physiologically based pharmacokinetic modeling of hexachlorobenzene: Incorporation of pathophysiological states following partial hepatectomy and hexachlorobenzene treatment. Toxicol. Sci. 91:29-41.
• Lee, S. K., Ou, Y. C., Andersen, M. E., and Yang, R. S. H. 2006. A physiologically-based pharmacokinetic model for lactational transfer of PCB153 with or without co-exposure of PCB 126 in mice. Arch. Toxicol. 2007.
• Yang, R. S. H., and Lu, Y. 2007. The Application of Physiologically Based Pharmacokinetic (PBPK) Modeling to Risk Assessment, in "Risk Assessment for Environmental Health," Eds. M. G. Robson and W. A. Toscano, John Wiley & Sons, Hoboken, NJ., pp. 85-120.
• Reisfeld, B., Mayeno, A. N., Lyons, M. A., and Yang, R. S. H. 2007. Physiologically-Based Pharmacokinetic and Pharmacodynamic Modeling, in Computational Toxicology. Risk Assessment For Pharmaceutical and Environmental Chemicals, Ed. S. Ekins, John Wiley & Sons, Hoboken, NJ., pp. 33-69.
• Yang, R. S. H., Chang, L. W., Wu, J. P., Tsai, M. H., Wang, H. J., Kuo, Y. C., Yeh, T. K., Yang, C. S., and Lin, P. P. 2007. Persistent tissue kinetics and redistribution of a nanoparticle, Quantum Dot 705, in mice: ICP-MS quantitative assessment. Environ. Health Perspect. 115:1339-1343. [Online publication, 14 June 2007] http://ehp.niehs.nih.gov/docs/2007/10290/abstract.html.
• Yang, R. S. H., and Dennison, J. E., Jr. 2007. Initial analyses of the relationship between "thresholds" of toxicity for individual chemicals and "interaction thresholds" for chemical mixtures. Toxicol. Appl. Pharmacol. 223:133-138.
• Lu, Y., Lohitnavy, M., Reddy, M., Lohitnavy, O., Eickman, E., Ashley, A., Gerjevic, L., Xu, Y., Conolly, R. B., and Yang, R. S. H. 2007. Quantitative analysis of liver GST-P foci promoted by a chemical mixture of hexachlorobenzene and PCB 126: Implication of size-dependent cellular growth kinetics. Arch. Toxicol. 82:103-116 [E-publication, Sept. 14, 2007].
• Lohitnavy, M., Lu, Y., Lohitnavy, O., Chubb, L.S., Hirono, S., and Yang, R.S.H., 2008. A possible role of multidrug-resistance-associated protein 2 (Mrp2) in hepatic excretion of PCB126, an environmental contaminant: PBPK/PD modeling. Toxicol.Sci. 104:27-39.
• Lin, P.P., Chen, J.W., Chang, L.W., Wu, J.P., Redding, L., Chang, H., Yeh, T.K., Yang, C.S., Tsai, M.H., Wang, H.J., Kuo, Y.C. and Yang, R.S.H., 2008. Computational and ultrastructural toxicology of a nanoparticle, Quantum Dot 705, in mice. Environ. Sci. Technol. 42:6264-6270.
• Lyons, M., Yang, R. S. H., Mayeno, A. N., and Reisfeld, B.  2008.  Computational toxicology of chloroform: reverse dosimetry using Bayesian inference, Markov Chain Monte Carlo simulation, and human biomonitoring data. Environ. Health Perspect. 116:1040-1046.
• Redding, L. E., Sohn, M. D., McKone, T. E., Chen, J. W., Wang, S. L., Hsieh, D. P. H., and Yang, R. S. H.  2008.  Population Physiologically-Based Pharmacokinetic Modeling for the Human Lactational Transfer of PCB 153 with Consideration of Worldwide Human Biomonitoring Results. Environ. Health Perspect. 116:1629-1634.
• Lee, S. K., Hamer, D., Bedwell, C. L., and Yang, R. S. H.  2009.  Effect of PCBs on the lactational transfer of methyl mercury in mice: PBPK modeling.  Environ. Toxicol. Pharmacol.  27:75-83.
• Yang, R. S. H., Mayeno, A. N., Lyons, M., and Reisfeld, B.  2010.  The Application of Physiologically-Based Pharmacokinetics (PBPK), Bayesian Population PBPK Modeling, and Biochemical Reaction Network (BRN) Modeling to Chemical Mixture Toxicology, in "Toxicology of Chemical Mixtures," Ed. M. Mumtaz, John Wiley & Sons, Hoboken, NJ., pp. 531-553.
• Yang, R. S. H.  2010.  Toxicologic Interactions Of Chemical Mixtures, in "Comprehensive Toxicology. Vol. 1. General Principles," Ed. J. Bond, Elsevier Ltd., Oxford, England, in press.
• Weijs, L., Yang, R. S. H.,  Covaci, A., Das, K., and Blust, R.  2010.  Physiologically based pharmacokinetic (PBPK) models for lifetime exposure to PCB 153 in male and female harbour porpoises (Phocoena phocoena):  Model development and evaluation.  Environ. Sci. Technol. 44:7023-7030.
• Yang, R. S. H., Chang, L. W., Yang, C. S., and Lin, P. P.  2010.  Pharmacokinetics and physiologically-based pharmacokinetic modeling of nanoparticles.  J. Nanosci. Nanotechnol. In press.