Permeability and Chromium Absorption

Reasonable solubility is a prerequisite for absorption of either Cr(III) or Cr(VI). Insoluble chromium compounds were used historically as markers of gastrointestinal transit time. 

Cr(III) is very poorly transferred across membranes. It is absorbed only to a limited extent, usually less than 1%, from soluble Cr(III) salts in the gastrointestinal tract (Mertz et al. 1965 Mackenzie et al. 1959) and the lung (Edel and Sabbioni 1985). Soluble salts of Cr(VI) are more readily absorbed from both the lung (Bract and van Dura 1983) and the gastrointestinal tract (Mackenzie et al. 1959) than are soluble salts of Cr(III). 

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