Chromium in urine, serum and red blood cells in the biological monitoring of workers exposed to different chromium valency states.
Using personal air sampling exposure to hexavalent and trivalent chromium was measured in 22 workers mainly exposed to Cr(VI) and in 15 workers mainly exposed to Cr(III) as basic chromium sulphate. Determination of Cr(VI) in the urine of all the subjects using a selective technique by ETA-AAS and liquid anion exchangers failed to show detectable amounts of the hexavalent form, the detection limit of the technique being 0.05 micrograms/L. A clear relationship between exposure and postshift urinary total chromium was found in subjects exposed to Cr(VI), while urinary levels in workers exposed to chromic sulphate high concentration proved lower. Determination of total chromium in serum and red blood cells showed a significant increase of chromium levels in erythrocytes of workers exposed to Cr(VI) while in subjects mainly exposed to Cr(III) an increase of the serum fraction was observed. The results demonstrate that Cr(III) is absorbed through the respiratory tract, but its kinetics and distribution in the body are not the same as for Cr(VI), and are not adequately monitored by short-term urinary determinations. Oxidation states of chromium largely influence uptake, mechanism of absorption, transport and organ distribution as well as toxicity of chromium-containing compounds. In particular, hexavalent derivatives are known to induce adverse effects, both acute and chronic, in occupationally exposed subjects, while there is little conclusive evidence for toxic effects caused by trivalent chromium compounds. Biological monitoring of exposure to chromium(VI) has usually been performed by determining total chromium levels in urine, whereas biological monitoring data in subjects occupationally exposed to Cr(III) are still scanty.(ABSTRACT TRUNCATED AT 250 WORDS)
Minoia
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Laboratorio di Igiene Industriale, Fondazione Clinica Lavoro, Pavia, Italy.
Cavalleri
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D002857:Chromium / Q000097:blood* / Q000652:urine; D017608:Chromium Compounds; D004781:Environmental Exposure; D004912:Erythrocytes / Q000032:analysis*; D006801:Humans; D007221:Industry; D008991:Monitoring, Physiologic; D011192:Potassium Dichromate; D012016:Reference Values; D013431:Sulfates; D014896:Welding
D017608:Chromium Compounds; D013431:Sulfates; D002857:Chromium; C040874:chromium sulfate; D011192:Potassium Dichromate