Agent Name |
Chromium and compounds |
CAS Number |
7440-47-3, varies |
Formula |
Cr, varies |
Major Category |
Metals |
Synonyms |
Chrome; Chromium compounds; [NIOSH] |
Category |
Elements, Metallic |
Description |
Blue-white to steel-gray, lustrous, brittle, hard, odorless solid; [NIOSH] |
Sources/Uses |
MINING, SMELTING, OR METALLURGY: Ore mining and crushing operations; Alloy production; Produce chromates from chromite; MANUFACTURING: Textile dyes; Paint pigments; Chrome plating; Leather tanning; Printing inks and toners; Photoengraving; Automotive & aircraft parts; Joint prostheses; Refractory bricks & kilns; USING: Heat or machine chromium alloys; Arc weld stainless steel; Spray paint Cr pigments; Mix and lay cement or concrete; Use water system corrosion inhibitors, wood preservatives, or glassware-cleansing solutions; Use hexavalent chromates in hardeners for epoxy resin sealants; |
Comments |
Chromium metal and Cr III compounds are IARC 3 (not classifiable), while the Cr VI compounds are IARC 1 (human carcinogens); Hexavalent chromium compounds (Cr VI) include: A) water-soluble compounds: chromium trioxide (chromic acid), and monochromates and dichromates of sodium, potassium, ammonium, lithium, cesium and rubidium; B) water-insoluble compounds: zinc chromate, strontium chromate and sintered chromium trioxide; [ACGIH] "NIOSH considers all Cr(VI) compounds (including chromic acid, tert-butyl chromate, zinc chromate, and chromyl chloride) to be potential occupational carcinogens." [NIOSH Pocket Guide Appendix] "Compounds of Cr III do not cause chrome ulcerations and do not generally initiate allergic dermatitis without prior sensitization by CrVI compounds." [ILO Encyclo, Vol 3, p. 63.1-63.68] Skin absorption is good for Cr VI, poor for Cr III. [Zenz, p. 487] Chromates, the most common cause of allergic contact dermatitis, are released as hexavalent chromium from chrome-plated metal tools and machine parts. [Marks, p. 117-9] Chromium is genotoxic, and animal experiments show effects on sperm motility. No available evidence of birth defects in humans. [Frazier] Chronic exposure to hexavalent chromium may cause mild to moderate liver injury. [ATSDR Case Studies # 4] Kidney injury has been reported in workers exposed to hexavalent chromium compounds; [ACGIH] Asthma reported in printer, plater, welder, and tanner (chromium and nickel); [Malo] Allergic contact dermatitis in agricultural workers, construction workers, mechanics, and printers; [Marks] Can cause immunologic, occupational contact urticaria; [Kanerva 2004, p. 104] |
Exposure Assessment |
BEI |
For chromium (VI), water-soluble fume: Total Cr in urine = 10 ug/L (increase during shift) or 25 ug/L (end of shift at end of workweek); |
Skin Designation (ACGIH) |
No |
Bioaccumulates |
Yes |
TLV (ACGIH) |
0.5 mg/m3 , as Cr(metal, Cr(III) inorganic compds), 0.05 mg/m3, as Cr(Cr(VI)water sol. inorganic compds), 0.01 mg/m3,as Cr(Cr(VI) water insol. inorganic compds) |
PEL (OSHA) |
1 mg/m3(metal), 0.5 mg/m3, as Cr(Cr(II) and Cr(III) inorganic compds), 0.005 mg/m3, as Cr(VI)(water sol. and insol. inorganic compds) |
IDLH (NIOSH) |
250 mg/m3,as Cr(metal and Cr(II)compds), 25 mg/m3, as Cr(Cr(III)compds) |
Excerpts from Documentation for IDLHs |
The available toxicological data show no evidence that an acute exposure to a high concentration of chromium metal would impede escape or cause any irreversible health effects within 30 minutes. |
Explanatory Notes |
Melting Point = 3452 degrees F; Boiling Point = 4788 degrees F; |
Half Life |
Blood: 24 days; body: initial elimination 1/2 life = 2-3 days; extended 1/2 life = 1 month; [TDR, p. 368] After chronic exposure, workers can have high levels of chromium in the urine for years. [ACGIH] |
Reference Link |
ATSDR - ToxFAQs - Chromium |
Adverse Effects |
Asthma |
Yes |
Lung Cancer |
Yes |
Dermatotoxin |
Skin Burns |
Skin Sensitizer |
Yes |
Hepatotoxin |
Hepatotoxin, Secondary |
Nephrotoxin |
Yes |
Reproductive Toxin |
Yes |
IARC Carcinogen |
Known Carcinogen, (Cr(VI) water sol. and insol. compds) |
Links to Other NLM Databases |
Health Studies |
Human Health Effects from Hazardous Substances Data Bank: CHROMIUM COMPOUNDS CHROMIUM, ELEMENTAL
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