Agent Name
Alternative Name
Zirconium and compounds
CAS Number
7440-67-7; varies
Zr, varies
Major Category
Zirconium metal: Synonyms of zirconium compounds vary depending upon the specific compound; [NIOSH] Zirconium and compounds; UN1358; UN1932; UN2008; UN2009; UN2858; UN1308;
Metals, Inorganic Compounds
Metal: Soft, malleable, ductile, solid or gray to gold, amorphous; [NIOSH]
The metal is used in nuclear energy technology, photoflash bulbs, vacuum tubes, and steel manufacturing (as a scavenger). Zirconium oxide is used in ceramic colorants, metal hardening (platinum and ruthenium), and as a radiopaque material for diagnostic x-rays. Zirconium chloride is used in textiles (water repellant) and tanning. Zircon is a natural zirconium silicate used to make refractories and other ceramics. It is also used as an abrasive. Water soluble zirconium compounds are used in cosmetics. [ACGIH]
Other than the skin and respiratory irritant effects of zirconium chloride, work-related diseases caused by zirconium have not been documented. [ACGIH] Zirconium compounds, both soluble and insoluble, have the following notation, "Danger of sensitization of the airways and the skin." [MAK] "Repeated inhalation of zirconium tetrachloride mist by dogs for 2 months at 6 mg/m3 as zirconium caused slight decreases in hemoglobin and in erythrocyte counts, with some increases in mortality over that of controls; these effects may have been due to the liberation of hydrogen chloride." [NIOSH Guidelines for Chemical Hazards] "Generally considered to be of low toxicity." Zirconium chloride (ZrCl4) can cause acute pneumonitis. No lung changes were found in 32 workers with 1-17 years of exposure to zirconium metal reactor parts. A lens grinder who mixed zirconium oxide powder and polished optical lenses developed interstitial fibrosis after a latency of 15 years. [Harber, p. 479, 487, 506] Soluble zirconium compounds include nitrates, acetates, sulfates, chlorides, bromides, iodides, and salts of Na, K, and ammonium; Insoluble zirconium compounds include hydroxides, carbonates, and phosphates; [Nordberg, p. 19]
Biomedical References

Exposure Assessment

Skin Designation (ACGIH)
Insufficient data
5 mg/m3, as Zr
10 mg/m3, as Zr
5 mg/m3, as Zr (compounds)
1 mg/m3, inhalable fraction (elemental)
25 mg/m3, as Zr
Excerpts from Documentation for IDLHs
The available toxicological data indicate that zirconium compounds possess a low order of toxicity. The chosen IDLH has been based on the citation by NIOSH [1976] that a 30­minute exposure to 500 mg/m3 of zirconium nitrate is the lowest concentration of this substance which has been shown to be lethal to rats [Mogilevskaya 1967].
Explanatory Notes
"Metal: Combustible, but solid form is difficult to ignite; however, powder form may ignite SPONTANEOUSLY and can continue burning under water." [NIOSH] The Guide from Emergency Response Guidebook is for "zirconium powder, dry."

Adverse Effects

ACGIH Carcinogen
Not Classifiable

Diseases, Processes, and Activities Linked to This Agent


Occupational diseases associated with exposure to this agent: