(Cr) Toxicity | ATSDR - CSEM - Agency for Toxic Substances and ...
(Cr) Toxicity | ATSDR - CSEM - Agency for Toxic Substances and ...
(Cr) Toxicity | ATSDR - CSEM - Agency for Toxic Substances and ...
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<strong>Agency</strong> <strong>for</strong> <strong>Toxic</strong> <strong>Substances</strong> <strong>and</strong> Disease Registry Chromium <strong><strong>Toxic</strong>ity</strong><br />
Case Studies in Environmental Medicine (<strong>CSEM</strong>)<br />
Key Points<br />
Progress Check<br />
• <strong>Cr</strong>(VI) is better absorbed from the lungs, gut, <strong>and</strong> skin than is <strong>Cr</strong>(III).<br />
• After absorption, <strong>Cr</strong>(VI) is reduced to <strong>Cr</strong>(III).<br />
• The difference in bioavailability <strong>and</strong> bioactivity between <strong>Cr</strong>(III) <strong>and</strong><br />
<strong>Cr</strong>(VI) might account <strong>for</strong> the differences in toxicity. <strong>Cr</strong>(III) is an<br />
essential dietary nutrient whereas <strong>Cr</strong>(VI) poses a significant risk of<br />
lung cancer.<br />
• <strong>Cr</strong>(III) is excreted, primarily in the urine.<br />
6. Which of the following statements about metabolism of an absorbed dose<br />
of chromium is correct?<br />
A. <strong>Cr</strong>(VI) is rapidly taken up by erythrocytes after absorption <strong>and</strong><br />
reduced to <strong>Cr</strong>(III) inside the red blood cells.<br />
B. <strong>Cr</strong>(III) is widely distributed in the body <strong>and</strong> accounts <strong>for</strong> most of the<br />
chromium in plasma or tissues.<br />
C. Excretion of absorbed chromium occurs primarily via urine.<br />
D. All of the above.<br />
To review relevant content, see “Absorption” <strong>and</strong> “Metabolic Pathways” in<br />
this section.<br />
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