Anatomy and Physiology Relevant to Inhalation, Oral, and Dermal Model Development. J. N. McDougal, Geo-Centers, Inc.; A. M. Jarabek, USEPA; and W. L. Roth, USFDA
Biologically-based models require appropriate parameters that reflect the relevant anatomy and physiology of the potential routes of chemical absorption. The suites of models that are being developed for each route range from complex to simple descriptions of absorption that must be qualitatively consistent The purpose of this presentation is to review the anatomical and physiological parameters of the gastrointestinal tract, respiratory tract, and skin that may be incorporated into these mathematical descriptions. Functionally, the gastrointestinal tract and the respiratory tract provide selective absorption of life sustaining substances. In sharp contrast, the skin behaves as a barrier that provides essential protective functions. All three routes require parameters to address descriptions of dose in the portal of entry as well as for delivery to remote tissues. Relevant anatomical structures for oral, inhalation and dermal absorption will be briefly described. Biological functions as well as weights, volumes and blood flows for each of the components of the barrier organ will be summarized. This review of structure and function will set the stage for choosing appropriate detail for absorption models as well as assisting the informed choice of parameters.
Go to . . .
2000 SRA Annual Meeting Table of Contents
2000 SRA Annual Meeting Author Index
Main Abstracts Menu Page
RiskWorld Home Page