Agent Name

Chromium and compounds

CAS Number

7440-47-3; varies

Formula

Cr, varies

Major Category

Metals

Synonyms

Chrome; Chromium compounds; [NIOSH]

Category

Chromium Compounds, Inorganic

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] "Bivalent compounds are unstable and have little commercial value." Hexavalent chromium is an uncommon cause of occupational asthma. [Asthma in the Workplace, p. 296]

Exposure Assessment
BEI

Chromium(VI), water-soluble fume (applicable for manual metal arc stainless steel welding only): Total Cr in urine = 10 ug/L (increase during shift) or 25 ug/L (end of shift at end of workweek)

Skin Designation (ACGIH)

Insufficient data

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
Nephrotoxin

Yes

Reproductive Toxin

Yes

Skin Sensitizer

Yes

Asthma

Yes

Hepatotoxin

Hepatotoxin, Secondary

Dermatotoxin

Skin Burns

IARC Carcinogen

Known Carcinogen

NTP Carcinogen

Human Carcinogen

ACGIH Carcinogen

Confirmed Human

Links to Other NLM Databases
Health Studies

Human Health Effects from Hazardous Substances Data Bank:

Toxicity Information

Chemical Information

Search ChemIDplus

Biomedical References

Search PubMed

Related Information in HazMap
Diseases

Occupational diseases associated with exposure to this agent:

Processes

Industrial Processes with risk of exposure:

Activities

Activities with risk of exposure: