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Thoughts on NAS Science and Decisions (2009)

Thoughts on NAS Science and Decisions (2009). John P. Christopher, Ph.D., D.A.B.T. California Department of Toxic Substances Control and TERA Fellow. Two Questions. Should toxicodynamic phenomena be modeled as a continuous function of dose through the low dose region?

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Thoughts on NAS Science and Decisions (2009)

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  1. Thoughts on NAS Science and Decisions (2009) John P. Christopher, Ph.D., D.A.B.T. California Department of Toxic Substances Control and TERA Fellow

  2. Two Questions • Should toxicodynamic phenomena be modeled as a continuous function of dose through the low dose region? • Does the NAS paradigm for risk assessment omit the inevitable connections to risk-benefit and risk management?

  3. Continuous Variable? Considering all the levels at which an organism responds to a chemical stressor - And moving upward through those levels of organization (increasing dose and response) - Is it valid to describe toxicodynamics with a smoothly increasing function of dose in the low-dose region?

  4. Continuous Variable? Martin et al., Environmental Health Perspectives, , 117(3): 392–399,2009

  5. Continuous Variable? Taken from Wikipedia Commons

  6. Continuous Variable? Pupillary Response, http://autonomy.caltech.edu/biomedicine/modelling.html

  7. Continuous Variable? Thyroid Pituitary Axis, http://www.abc.net.au/health/library/stories/2005/06/16/1831822.htm

  8. Continuous Variable? Integration throughout the Organism via the Pituitary Gland

  9. Continuous Variable?

  10. Continuous Variable? My Viewpoint: Classical dose-response functions are clearly valid in the region of observable adverse effects, BUT Let us keep our minds open to the evolving descriptions coming from Systems Biology.

  11. DOSE-RESPONSE ASSESSMENT HAZARD IDENTIFICATION RISK CHARACTERIZATION EXPOSURE ASSESSMENT Risk Assessment Paradigm

  12. DOSE-RESPONSE ASSESSMENT HAZARD IDENTIFICATION RISK COMMUNICATION RISK CHARACTERIZATION EXPOSURE ASSESSMENT Risk Assessment Paradigm

  13. DOSE-RESPONSE ASSESSMENT HAZARD IDENTIFICATION RISK COMMUNICATION RISK CHARACTERIZATION EXPOSURE ASSESSMENT Risk-Benefit is the Inescapable Matrix for Risk Assessment and Risk Management Risk Benefit Matrix

  14. Our common metric is Risk. Everyone else’s is Money. So, build bridges with the social scientists who monitize risk for the managers of the world. $ £€¥руб₨

  15. Advice from Prof. Einstein "God does not care about our mathematical difficulties. He integrates empirically." “I have little use for scientists who find the thinnest part of a board of wood and drill a large number of holes.” "Anyone who has never made a mistake has never tried anything new." “Learn from yesterday, live for today, hope for tomorrow. The important thing is not to stop questioning.”

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