Pharmacokinetic Modeling of Trivalent and Hexavalent Chromium Based on Ingestionand Inhalation of Soluble Chromium Compounds

摘要

A physiologically-based model of chromium disposition in the rat has beendeveloped. Absorption, distribution, and excretion of chromium are superimposed on a general physiological model of rat growth and development. The model considers both Cr (VI) and Cr (III), administered either orally or by inhalation. It incorporates reduction of Cr (VI) to Cr (III) in all tissues including the lung and the GI tract. Chromium is cleared from the lung by systemic absorption and by mucociliary clearance into the GI tract. Parameter values are based on literature data and on the results of a concurrent experimental study in which rats were given either Cr (111) or Cr (VI) either in the drinking water or by inhalation. Blood, tissue, urine, and fecal chromium levels were monitored on days 2, 5, 10, 20, and 40 of the 40-day exposure period, and at 20 days postexposure. Cr(VI), Cr(III), Oral exposure, Inhalation exposure, Physiologically-based model.