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Chromium

PubChem CID
23976
Structure
Chromium_small.png
Molecular Formula
Synonyms
  • CHROMIUM
  • 7440-47-3
  • CR
  • Chrome
  • Chrom
Molecular Weight
51.996 g/mol
Computed by PubChem 2.2 (PubChem release 2021.10.14)
Element Name
Dates
  • Create:
    2004-09-16
  • Modify:
    2025-01-04
Description
Chromium is a naturally occurring element found in rocks, animals, plants, soil, and in volcanic dust and gases. Chromium is present in the environment in several different forms. The most common forms are chromium(0), chromium(III), and chromium(VI). No taste or odor is associated with chromium compounds. Chromium(III) occurs naturally in the environment and is an essential nutrient. Chromium(VI) and chromium(0) are generally produced by industrial processes. The metal chromium, which is the chromium(0) form, is used for making steel. Chromium(VI) and chromium(III) are used for chrome plating, dyes and pigments, leather tanning, and wood preserving.
Chromium (hexavalent compounds) can cause cancer according to California Labor Code. It can cause developmental toxicity, female reproductive toxicity and male reproductive toxicity according to an independent committee of scientific and health experts.
Chromium is a very hard gray solid with a metallic luster. (NTP, 1992)
National Toxicology Program, Institute of Environmental Health Sciences, National Institutes of Health (NTP). 1992. National Toxicology Program Chemical Repository Database. Research Triangle Park, North Carolina.

1 Structures

1.1 2D Structure

Chemical Structure Depiction
Chromium.png

1.2 Crystal Structures

2 Names and Identifiers

2.1 Computed Descriptors

2.1.1 IUPAC Name

chromium
Computed by Lexichem TK 2.7.0 (PubChem release 2021.10.14)

2.1.2 InChI

InChI=1S/Cr
Computed by InChI 1.0.6 (PubChem release 2021.10.14)

2.1.3 InChIKey

VYZAMTAEIAYCRO-UHFFFAOYSA-N
Computed by InChI 1.0.6 (PubChem release 2021.10.14)

2.1.4 SMILES

[Cr]
Computed by OEChem 2.3.0 (PubChem release 2024.12.12)

2.2 Molecular Formula

Cr
Computed by PubChem 2.2 (PubChem release 2021.10.14)

2.3 Other Identifiers

2.3.1 CAS

7440-47-3
16065-83-1
19498-56-7

2.3.2 Deprecated CAS

188785-87-7, 195161-82-1
195161-82-1

2.3.3 European Community (EC) Number

2.3.4 UNII

2.3.5 UN Number

2.3.6 ChEBI ID

2.3.7 DrugBank ID

2.3.8 DSSTox Substance ID

2.3.9 ICSC Number

2.3.10 KEGG ID

2.3.11 NCI Thesaurus Code

2.3.12 Nikkaji Number

2.3.13 RTECS Number

2.3.14 Wikidata

2.3.15 Wikipedia

2.4 Synonyms

2.4.1 MeSH Entry Terms

Chromium

2.4.2 Depositor-Supplied Synonyms

3 Chemical and Physical Properties

3.1 Computed Properties

Property Name
Molecular Weight
Property Value
51.996 g/mol
Reference
Computed by PubChem 2.2 (PubChem release 2021.10.14)
Property Name
Hydrogen Bond Donor Count
Property Value
0
Reference
Computed by Cactvs 3.4.8.18 (PubChem release 2021.10.14)
Property Name
Hydrogen Bond Acceptor Count
Property Value
0
Reference
Computed by Cactvs 3.4.8.18 (PubChem release 2021.10.14)
Property Name
Rotatable Bond Count
Property Value
0
Reference
Computed by Cactvs 3.4.8.18 (PubChem release 2021.10.14)
Property Name
Exact Mass
Property Value
51.940505 Da
Reference
Computed by PubChem 2.2 (PubChem release 2021.10.14)
Property Name
Monoisotopic Mass
Property Value
51.940505 Da
Reference
Computed by PubChem 2.2 (PubChem release 2021.10.14)
Property Name
Topological Polar Surface Area
Property Value
0 Ų
Reference
Computed by Cactvs 3.4.8.18 (PubChem release 2021.10.14)
Property Name
Heavy Atom Count
Property Value
1
Reference
Computed by PubChem
Property Name
Formal Charge
Property Value
0
Reference
Computed by PubChem
Property Name
Complexity
Property Value
0
Reference
Computed by Cactvs 3.4.8.18 (PubChem release 2021.10.14)
Property Name
Isotope Atom Count
Property Value
0
Reference
Computed by PubChem
Property Name
Defined Atom Stereocenter Count
Property Value
0
Reference
Computed by PubChem
Property Name
Undefined Atom Stereocenter Count
Property Value
0
Reference
Computed by PubChem
Property Name
Defined Bond Stereocenter Count
Property Value
0
Reference
Computed by PubChem
Property Name
Undefined Bond Stereocenter Count
Property Value
0
Reference
Computed by PubChem
Property Name
Covalently-Bonded Unit Count
Property Value
1
Reference
Computed by PubChem
Property Name
Compound Is Canonicalized
Property Value
Yes
Reference
Computed by PubChem (release 2021.10.14)

3.2 Experimental Properties

3.2.1 Physical Description

Chromium is a very hard gray solid with a metallic luster. (NTP, 1992)
National Toxicology Program, Institute of Environmental Health Sciences, National Institutes of Health (NTP). 1992. National Toxicology Program Chemical Repository Database. Research Triangle Park, North Carolina.
Dry Powder, Pellets or Large Crystals; Other Solid; Dry Powder
Blue-white to steel-gray, lustrous, brittle, hard, odorless solid; [NIOSH]
GREY POWDER.
Blue-white to steel-gray, lustrous, brittle, hard, odorless solid.
Appearance and odor vary depending upon the specific compound.

3.2.2 Color / Form

Steel-gray, lustrous metal; body-centered cubic structure
O'Neil, M.J. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. Cambridge, UK: Royal Society of Chemistry, 2013., p. 398
Blue-white to steel-gray, lustrous, brittle, hard solid
NIOSH. NIOSH Pocket Guide to Chemical Hazards. Department of Health & Human Services, Centers for Disease Control & Prevention. National Institute for Occupational Safety & Health. DHHS (NIOSH) Publication No. 2010-168 (2010). Available from: https://www.cdc.gov/niosh/npg
Hard, brittle, semigray metal
Lewis, R.J. Sr.; Hawley's Condensed Chemical Dictionary 15th Edition. John Wiley & Sons, Inc. New York, NY 2007., p. 299

3.2.3 Odor

Odorless
NIOSH. NIOSH Pocket Guide to Chemical Hazards. Department of Health & Human Services, Centers for Disease Control & Prevention. National Institute for Occupational Safety & Health. DHHS (NIOSH) Publication No. 2010-168 (2010). Available from: https://www.cdc.gov/niosh/npg

3.2.4 Boiling Point

4788 °F at 760 mmHg (NTP, 1992)
National Toxicology Program, Institute of Environmental Health Sciences, National Institutes of Health (NTP). 1992. National Toxicology Program Chemical Repository Database. Research Triangle Park, North Carolina.
2642
MSDS
4788 ° F
2642 °C
O'Neil, M.J. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. Cambridge, UK: Royal Society of Chemistry, 2013., p. 398
4788 °F

3.2.5 Melting Point

3452 °F (NTP, 1992)
National Toxicology Program, Institute of Environmental Health Sciences, National Institutes of Health (NTP). 1992. National Toxicology Program Chemical Repository Database. Research Triangle Park, North Carolina.
1900
MSDS
3452 °F
1907 °C
Haynes, W.M. (ed.). CRC Handbook of Chemistry and Physics. 95th Edition. CRC Press LLC, Boca Raton: FL 2014-2015, p. 4-10
1900 °C

3.2.6 Solubility

Insoluble (NIOSH, 2024)
Insoluble
MSDS
Insoluble in water
Lewis, R.J. Sr.; Hawley's Condensed Chemical Dictionary 15th Edition. John Wiley & Sons, Inc. New York, NY 2007., p. 299
Soluble in acids (except nitric) and strong alkalies.
Lewis, R.J. Sr.; Hawley's Condensed Chemical Dictionary 15th Edition. John Wiley & Sons, Inc. New York, NY 2007., p. 299
Solubility in water: none

3.2.7 Density

7.2 (NTP, 1992) - Denser than water; will sink
National Toxicology Program, Institute of Environmental Health Sciences, National Institutes of Health (NTP). 1992. National Toxicology Program Chemical Repository Database. Research Triangle Park, North Carolina.
7.14 at 20 °C
O'Neil, M.J. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. Cambridge, UK: Royal Society of Chemistry, 2013., p. 398
7.15 g/cm³
7.14
7.2

3.2.8 Vapor Pressure

1 mmHg at 2941 °F (NTP, 1992)
National Toxicology Program, Institute of Environmental Health Sciences, National Institutes of Health (NTP). 1992. National Toxicology Program Chemical Repository Database. Research Triangle Park, North Carolina.
Vapor pressure: 1 Pa at 1383 °C (sublimes)
Lide, DR (ed.). CRC Handbook of Chemistry and Physics. 81st Edition. CRC Press LLC, Boca Raton: FL 2000, p. 6-66
2.45X10-8 Pa at 1000 deg K; 0.0239 Pa at 1400 deg K; 1.80 Pa at 1600 deg K; 774 Pa at 2000 deg K
Haynes, W.M. (ed.). CRC Handbook of Chemistry and Physics. 95th Edition. CRC Press LLC, Boca Raton: FL 2014-2015, p. 4-127
0 mmHg (approx)
depends upon the specific compound

3.2.9 Stability / Shelf Life

Stable under recommended storage conditions.
Sigma-Aldrich; Safety Data Sheet for Chromium. Product Number: 374849, Version 4.8 (Revision Date 02/27/2015). Available from, as of October 19, 2015: https://www.sigmaaldrich.com/safety-center.html
Resists atmospheric attack at ambient temperatures.
O'Neil, M.J. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. Cambridge, UK: Royal Society of Chemistry, 2013., p. 398

3.2.10 Corrosivity

The silver soldered stainless steel wire corroded more than the cobalt-chromium type, & released more nickel & chromium than did the cobalt-chromium wires.
BERGE M ET AL; ACTA ODONTOL SCAND 40 (2): 75 (1982)

3.2.11 Heat of Vaporization

81.7 kcal/mol (at the boiling point)
O'Neil, M.J. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. Cambridge, UK: Royal Society of Chemistry, 2013., p. 398

3.2.12 pH

Bivalent chromium compounds are basic; trivalent chromium compounds are amphoteric; hexavalent chromium compounds are acidic
Langard S, Lison D; Chromium, Molybdenum and Tungsten. Patty's Toxicology. 6th ed. (1999-2015). New York, NY: John Wiley & Sons, Inc. On-line Posting Date: 27 Jan 2012

3.2.13 Surface Tension

1590 + or - 50 mN/m in vacuum at 1950 °C (Sessile drop method); 1700 + or - 50 mN/m in air at melting point (Dynam drop wt method); 1520 mN/m in air or Helium at 1800 °C (Sessile drop method)
Weast, R.C. (ed.) Handbook of Chemistry and Physics, 68th ed. Boca Raton, Florida: CRC Press Inc., 1987-1988., p. F-21

3.2.14 Other Experimental Properties

Enthalpy of fusion: 403.9 J/g at the melting pt
Haynes, W.M. (ed.). CRC Handbook of Chemistry and Physics. 95th Edition. CRC Press LLC, Boca Raton: FL 2014-2015, p. 12-217
Under strongly oxidizing conditions, may be converted to hexavalent state & occur as chromate anions
National Research Council. Drinking Water & Health Volume 1. Washington, DC: National Academy Press, 1977., p. 242
Electronegativity (Pauling Scale): 1.6; orbital electrons: (Ar)3d5-4s1; abundance (% of earth's crust): 2X10-2
Osol, A. (ed.). Remington's Pharmaceutical Sciences. 16th ed. Easton, Pennsylvania: Mack Publishing Co., 1980., p. 360
Chromium is a mixture of four stable isotopes with mass numbers 50 (4.31%), 52 (83.76%), 53 (9.55%) and 54 (2.38%). Thermal neutron capture cross sections are 17, 0.8, 18 and 0.38 barns, respectively.
Lederer CM et al; Table of Isotopes 6th ed p.18 (1967) as cited in NAS; Medical and Biological Effects of Environmental Pollutants: Chromium p.3 (1974)
For more Other Experimental Properties (Complete) data for CHROMIUM, ELEMENTAL (9 total), please visit the HSDB record page.

3.3 SpringerMaterials Properties

3.4 Chemical Classes

Metals -> Chromium Compounds, Inorganic
Trace element

3.4.1 Cosmetics

Cosmetics ingredient -> Other (Specify)

3.4.2 Endocrine Disruptors

Potential endocrine disrupting compound
S109 | PARCEDC | List of 7074 potential endocrine disrupting compounds (EDCs) by PARC T4.2 | DOI:10.5281/zenodo.10944198

5 Chemical Vendors

6 Drug and Medication Information

6.1 Drug Indication

Indicated for use as a supplement to intravenous solutions given for total parenteral nutrition (TPN), to maintain chromium serum levels and to prevent depletion of endogenous stores and subsequent deficiency symptoms.

6.2 FDA National Drug Code Directory

6.3 Drug Labels

Active ingredient and drug
Homeopathic product and label

6.4 Clinical Trials

6.4.1 ClinicalTrials.gov

6.4.2 NIPH Clinical Trials Search of Japan

6.5 Reported Fatal Dose

1 to 3 grams of hexavalent chromium for an adult human. (A119)
A119: Barceloux DG: Chromium. J Toxicol Clin Toxicol. 1999;37(2):173-94. PMID:10382554

7 Food Additives and Ingredients

7.1 Associated Foods

8 Minerals

1 of 5
2 of 5
Formula
Cr
System
Cubic
3 of 5
Name
chromium
Link
4 of 5
IMA Number
IMA1980-094
Formula
Cr
IMA Symbol
Cr
5 of 5
Mineral Description
Chromium (Cr) has a wide range of uses in metals, chemicals, and refractories. It is one of the Nation's most important strategic and critical materials. Chromium use in iron, steel, and nonferrous alloys enhances hardenability and resistance to corrosion and oxidation. The use of chromium to produce stainless steel and nonferrous alloys are two of its more important applications. Other applications are in alloy steel, plating of metals, pigments, leather processing, catalysts, surface treatments, and refractories.
USGS Mineral Commodity Summaries (PDF links)
USGS Mineral Yearbook (PDF links)

9 Pharmacology and Biochemistry

9.1 Pharmacodynamics

Trivalent chromium is part of glucose tolerance factor, an essential activator of insulin-mediated reactions. Chromium helps to maintain normal glucose metabolism and peripheral nerve function. Chromium increases insulin binding to cells, increases insulin receptor density and activates insulin receptor kinase leading to enhanced insulin sensitivity. In chromium deficiency, intravenous administration of chromium resulted in normalization of the glucose tolerance curve from the diabetic-like curve typical of chromium deficiency.

9.2 MeSH Pharmacological Classification

Trace Elements
A group of chemical elements that are needed in minute quantities for the proper growth, development, and physiology of an organism. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed) (See all compounds classified as Trace Elements.)

9.3 FDA Pharmacological Classification

1 of 2
FDA UNII
0R0008Q3JB
Active Moiety
CHROMIUM
Pharmacological Classes
Established Pharmacologic Class [EPC] - Standardized Chemical Allergen
Pharmacological Classes
Physiologic Effects [PE] - Increased Histamine Release
Pharmacological Classes
Physiologic Effects [PE] - Cell-mediated Immunity
Pharmacological Classes
Chemical Structure [CS] - Allergens
FDA Pharmacology Summary
Chromium is a Standardized Chemical Allergen. The physiologic effect of chromium is by means of Increased Histamine Release, and Cell-mediated Immunity.
2 of 2
Non-Proprietary Name
CHROMIUM METALLICUM
Pharmacological Classes
Cell-mediated Immunity [PE]; Increased Histamine Release [PE]; Standardized Chemical Allergen [EPC]; Allergens [CS]

9.4 Absorption, Distribution and Excretion

Absorption
Chromium compounds are both absorbed by the lung and the gastrointestinal tract. Oral absorption of chromium compounds in humans can range between 0.5% and 10%, with the hexavalent (VI) chromium more easily absorbed than the trivalent (III) form. Absorption of chromium from the intestinal tract is low, ranging from less than 0.4% to 2.5% of the amount consumed. Vitamin C and the vitamin B niacin is reported to enhance chromium absorption. Most hexavalent Cr (VI) undergoes partial intragastric reduction to Cr (III) upon absorption, which is an action mainly mediated by sulfhydryl groups of amino acids. Cr (VI) readily penetrates cell membranes and chromium can be found in both erythrocytes and plasma after gastrointestinal absorption of Cr (IV). In comparison, the presence of chromium is limited to the plasma as Cr (III) displays poor cell membrane penetration. Once transported through the cell membrane, Cr (VI) is rapidly reduced to Cr (III), which subsequently binds to macromolecules or conjugate with proteins. Cr (III) may be bound to transferrin or other plasma proteins, or as complexes, such as glucose tolerance factor (GTF).
Route of Elimination
Absorbed chromium is excreted mainly in the urine, accounting for 80% of total excretion of chromium; small amounts are lost in hair, perspiration and bile. Chromium is excreted primarily in the urine by glomerular filtration or bound to a low molecular-weight organic transporter.
Volume of Distribution
Absorbed chromium is distributed to all tissues of the body and its distribution in the body depends on the species, age, and chemical form. Circulating Cr (III) following oral or parenteral administration of different compounds can be taken up by tissues and accumulates in the liver, kidney, spleen, soft tissue, and bone.
Clearance
Excretion of chromium is via the kidneys ranges from 3 to 50 μg/day. The 24-hour urinary excretion rates for normal human subjects are reported to be 0.22 μg/day.
The objective of the Part II analysis was to evaluate animal and in vitro toxicology studies of CoCr particles with respect to their physicochemistry and dose relevance to metal-on-metal (MoM) implant patients as derived from Part I. In the various toxicology studies, physicochemical characteristics were infrequently considered and administered doses were orders of magnitude higher than what occurs in patients. Co was consistently shown to rapidly release from CoCr particles for distribution and elimination from the body. CoCr micron sized particles appear more biopersistent in vivo resulting in inflammatory responses that are not seen with similar mass concentrations of nanoparticles. We conclude, that in an attempt to obtain data for a complete risk assessment, future studies need to focus on physicochemical characteristics of nano and micron sized particles and on doses and dose metrics relevant to those generated in patients or in properly conducted hip simulator studies. /CoCr particles/
Madl AK et al; Nanomedicine.11 (5): 1285-98 (2015)
The kinetics of metal ions release from orthodontic appliances in in vitro, in in vivo on pigs, and in vivo trials on patients (where hair samples were taken) was discussed. We have evaluated (by means of ICP-OES and ISO 17025) and compared the mass of Cr and Ni ions released. Not all the metal ions released from the appliance were transferred to hair tissue. The transfer factor was expressed as coefficient omega and evaluated as: omegaCr(patients) 33.0%, omegaCr(pigs) 17.2%, omegaNi(patients) 49.8%, omegaNi(pigs) 0.553%. The kinetics was described by a power function. Coefficient omega was used to combine the models: the in vitro and in vivo on animals on the one hand and the in vitro and in vivo on human on the other, which enabled the extrapolation of in vitro and translation of the results into in vivo conditions. The dose of metal ions released during orthodontic treatment was estimated.
Chojnacka K, Mikulewicz M; Environ Toxicol Pharmacol. 38 (3): 932-7 (2014)

9.5 Metabolism / Metabolites

The metabolism of Cr (VI) involves reduction by small molecules and enzyme systems to generate Cr (III) and reactive intermediates. During this process, free radicals can be generated, which is thought to induce damage of cellular components and cause toxicity of chromium. The metabolites bind to cellular constituents.
Chromium is absorbed from oral, inhalation, or dermal exposure and distributes to nearly all tissues, with the highest concentrations found in kidney and liver. Bone is also a major storage site and may contribute to long-term retention. Hexavalent chromium's similarity to sulfate and chromate allows it to be transported into cells via sulfate transport mechanisms. Inside the cell, hexavalent chromium is reduced first to pentavalent chromium, then to trivalent chromium by different pathways including ascorbate, glutathione, and nicotinamide adenine dinucleotide. Chromium is almost entirely excreted in the urine. (A12, L16)
A12: Salnikow K, Zhitkovich A: Genetic and epigenetic mechanisms in metal carcinogenesis and cocarcinogenesis: nickel, arsenic, and chromium. Chem Res Toxicol. 2008 Jan;21(1):28-44. Epub 2007 Oct 30. PMID:17970581
L16: ATSDR - Agency for Toxic Substances and Disease Registry (2008). Toxicological profile for chromium. U.S. Public Health Service in collaboration with U.S. Environmental Protection Agency (EPA). http://www.atsdr.cdc.gov/toxprofiles/tp7.html

9.6 Biological Half-Life

The elimination half-life of hexavalent chromium is 15 to 41 hours.
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]
TDR - Ryan RP, Terry CE, Leffingwell SS (eds). Toxicology Desk Reference: The Toxic Exposure and Medical Monitoring Index, 5th Ed. Washington DC: Taylor & Francis, 1999., p. 368
ACGIH - Documentation of the TLVs and BEIs, 7th Ed. Cincinnati: ACGIH Worldwide, 2020.

9.7 Mechanism of Action

Chromium is an essential nutrient involved in the metabolism of glucose, insulin and blood lipids. Its role in potentiating insulin signalling cascades has been implicated in several studies. Chromium upregulates insulin-stimulated insulin signal transduction via affecting effector molecules downstream of the insulin receptor (IR). IR-mediated signalling pathway involves phoshorylation of multiple intracellular domains and protein kinases, and downstream effector molecules. Upon activation by ligands, intracellular β-subunit of IR autophosphorylates and activates tyrosine kinase domain of the IR, followed by activation and phosphorylation of regulatory proteins and downstream signalling effectors including phosphatidylinositol 2-kinase (PI3K). PI3K activates further downstream reaction cascades to activate protein kinase B (Akt) to ultimately promote translocation of glucose transporter-4 (Glut4)-vesicles from the cytoplasm to the cell surface and regulate glucose uptake. Chromium enhances the kinase activity of insulin receptor β and increases the activity of downstream effectors, pI3-kinase and Akt. Under insulin-resistant conditions, chromium also promotes GLUT-4 transporter translocation that is independent of activity of IR, IRS-1, PI3-kinase, or Akt; chromium mediates cholesterol efflux from the membranes via increasing fluidity of the membrane by decreasing the membrane cholesterol and upregulation of sterol regulatory element-binding protein. As a result, intracellular GLUT-4 transporters are stimulated to translocate from intracellular to the plasma membrane, leading to enhanced glucose uptake in muscle cells. Chromium attenuates the activity of PTP-1B _in vitro,_ which is a negative regulator of insulin signaling. It also alleviates ER stress that is observed to be elevated the suppression of insulin signaling. ER stress is thought to activate c-Jun N-terminal kinase (JNK), which subsequently induces serine phosphorylation of IRS and aberration of insulin signalling. Transient upregulation of AMPK by chromium also leads to increased glucose uptake.
While the toxicity of metals and metalloids, like arsenic, cadmium, mercury, lead and chromium, is undisputed, the underlying molecular mechanisms are not entirely clear. General consensus holds that proteins are the prime targets; heavy metals interfere with the physiological activity of specific, particularly susceptible proteins, either by forming a complex with functional side chain groups or by displacing essential metal ions in metalloproteins. Recent studies have revealed an additional mode of metal action targeted at proteins in a non-native state; certain heavy metals and metalloids have been found to inhibit the in vitro refolding of chemically denatured proteins, to interfere with protein folding in vivo and to cause aggregation of nascent proteins in living cells. Apparently, unfolded proteins with motile backbone and side chains are considerably more prone to engage in stable, pluridentate metal complexes than native proteins with their well-defined 3D structure. By interfering with the folding process, heavy metal ions and metalloids profoundly affect protein homeostasis and cell viability. This review describes how heavy metals impede protein folding and promote protein aggregation, how cells regulate quality control systems to protect themselves from metal toxicity and how metals might contribute to protein misfolding disorders.
Tamas MJ et al; Biomolecules. 4(1): 252-67 (2014)

10 Use and Manufacturing

10.1 Uses

The metal chromium is used mainly for making steel and other alloys.
EPA CPDat Chemical and Product Categories
The Chemical and Products Database, a resource for exposure-relevant data on chemicals in consumer products, Scientific Data, volume 5, Article number: 180125 (2018), DOI:10.1038/sdata.2018.125
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; Chromium(VI) is present also as an impurity in Portland cement, and can be generated and given off during casting, welding, and cutting operations involving stainless steel, even if chromium was not originally present in its hexavalent state. [ACGIH] Stainless steels are a group of iron-based alloys containing at least 10.5% chromium. Chromium is used to make stainless steel corrosion resistant. . . . In ferrochromium operations, trivalent (insoluble) chromium (Cr3+) predominates, but hexavalent (soluble) chromium (Cr6+) also occurs at low levels, usually at below 1 ug m-3. [PMID 26950803]
ACGIH - Documentation of the TLVs and BEIs, 7th Ed. Cincinnati: ACGIH Worldwide, 2020.
Industrial Processes with risk of exposure

Steel Producing [Category: Industry]

Abrasive Blasting [Category: Clean]

Metal Preparation and Pouring [Category: Foundry]

Metal Machining [Category: Heat or Machine]

Welding [Category: Weld]

Electroplating [Category: Plate]

Metal Thermal Spraying [Category: Plate]

Semiconductor Manufacturing [Category: Industry]

Smelting Copper or Lead [Category: Industry]

Pulp and Paper Processing [Category: Industry]

Painting (Pigments, Binders, and Biocides) [Category: Paint]

Applying Wood Preservatives [Category: Other]

Mining [Category: Industry]

Plastic Composites Manufacturing [Category: Industry]

Cleaning Furnaces or Flues [Category: Clean]

Leather Tanning and Processing [Category: Industry]

Photographic Processing [Category: Other]

Fur Dressing and Dyeing [Category: Industry]

Cement Producing [Category: Industry]

Textiles (Printing, Dyeing, or Finishing) [Category: Industry]

Welding Over Coatings [Category: Weld]

Silk-Screen Printing [Category: Other]

Glass Manufacturing [Category: Industry]

Metal Extraction and Refining [Category: Industry]

Activities with risk of exposure

Ceramics making [Category: Hobbies]

Enameling [Category: Hobbies]

Painting [Category: Hobbies]

Glassblowing [Category: Hobbies]

Textile arts [Category: Hobbies]

Lithography printing [Category: Hobbies]

Smoking cigarettes [Category: Food & Drugs]

Living near chromium plating or chromate plant [Category: Environments]

In maufacturing of chrome-steel or chrome-nickel-steel alloys (stainless steel), nonferrous alloys, heat resistant bricks for refractory furnaces. To greatly increase strength, hardness and resistance of metals to abrasion, corrosion and oxidation. For chrome plating of other metals; leather tanning; as pigment and mordant; wood preservative. Use of (51)Cr as diagnostic aid.
O'Neil, M.J. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. Cambridge, UK: Royal Society of Chemistry, 2013., p. 398
Alloying and plating element on metal and plastic substrates for corrosion resistance, chromium-containing and stainless steels, protective coating for automotive and equipment accessories, nuclear and high temperature research, constituent of inorganic pigments.
Lewis, R.J. Sr.; Hawley's Condensed Chemical Dictionary 15th Edition. John Wiley & Sons, Inc. New York, NY 2007., p. 299
Cobalt-chromium stellite alloys (extrusion dies/turbine blades/valve seats); cobalt-chromium tungsten alloys (cemented carbide cutting tools); nickel chromium alloys (jet engine parts, electrical heating elements).
Ashford, R.D. Ashford's Dictionary of Industrial Chemicals. London, England: Wavelength Publications Ltd., 1994., p. 219
Forms heat-treatable copper alloys.
Twarog DL; Copper Alloys, Cast Copper Alloys. Kirk-Othmer Encyclopedia of Chemical Technology (1999-2015). John Wiley & Sons, Inc. Online Posting Date: December 4, 2000
For more Uses (Complete) data for CHROMIUM, ELEMENTAL (10 total), please visit the HSDB record page.
Substance listed with specific concentration in tattoo ink and/or permanent make up according to EU Commission Regulation 2020/2081. The concentration limit (by weight) is 0.00005%.
S86 | TATTOOINK | Regulated Tattoo Ink Ingredients as per EU regulation 2020/2081 | A list of regulated ingredients for tattoo ink and permanent make up (https://ec.europa.eu/jrc/en/news/how-safe-are-our-tattoos-and-permanent-makeup), Appendix 13 added to Commission Regulation (EU) 2020/2081, 14 December 2020 amending Annex XVII of REACH (https://eur-lex.europa.eu/eli/reg/2020/2081/oj). Dataset DOI:10.5281/zenodo.5710243
Elemental chromium is used mainly for making steel. Hexavalent chromium is used for chrome plating, dyes and pigments, leather tanning, and wood preserving. (A12, L17)
A12: Salnikow K, Zhitkovich A: Genetic and epigenetic mechanisms in metal carcinogenesis and cocarcinogenesis: nickel, arsenic, and chromium. Chem Res Toxicol. 2008 Jan;21(1):28-44. Epub 2007 Oct 30. PMID:17970581
L17: Wikipedia. Chromium. Last Updated 5 March 2009. http://en.wikipedia.org/wiki/Chromium

10.1.1 Use Classification

Chemical Classes -> Inorganic substances
Hazardous Air Pollutants (HAPs)
Hazard Classes and Categories -> Flammable - 3rd degree

10.1.2 Industry Uses

  • Dyes
  • Alloys
  • Intermediates
  • Intermediate
  • Not Known or Reasonably Ascertainable
  • Fillers
  • Other (specify)
  • Other
  • Abrasives

10.1.3 Consumer Uses

  • Dyes
  • Alloys
  • Not Known or Reasonably Ascertainable
  • Intermediate
  • Fillers
  • Other (specify)
  • Paint additives and coating additives not described by other categories
  • Other

10.1.4 Household Products

California Safe Cosmetics Program (CSCP)

Cosmetics product ingredient: Chromium and chromium compounds

Product count: 1

Household & Commercial/Institutional Products

Information on 1 consumer products that contain Chromium in the following categories is provided:

• Auto Products

10.2 Methods of Manufacturing

Chromium metal is commercially produced in the United States by the reduction of chromite ore with carbon, aluminum, or silicon, and subsequent purification.
HHS/ATSDR; Toxicological Profile for Chromium p.351 PB2013-105788 (September 2012). Available from, as of November 19, 2015: https://www.atsdr.cdc.gov/toxprofiles/index.asp
Chromium is extracted from its ores by alkaline or acidic dissolution. In alkali dissolution, finely ground chrome ore is roasted with Na2CO3 under oxidizing conditions at ca. 1100 °C. The sodium chromate is leached from the calcine; most of the gangue is insoluble. The solution containing hexavalent Cr can be reduced with SO2 and used for electrowinning, or Na2Cr2O7 can be crystallized from it. The Na2Cr2O7 can be converted to CrO3 for use in electrolysis or to Cr2O3 for use in metallothermics. Chrome ore can be dissolved in acid if an oxidizing agent is present. However, Fe, Al, and Mg also dissolve and must be removed. The preferred acidic dissolution technique is to reduce the ore with carbon, forming ferrochromium, which is ground and dissolved in sulfuric acid. The only significant impurity carried over is Fe, which is removed by crystallization as iron(II) ammonium sulfate. The Cr in the solution is in the +3 valence state and with additional purification is used to produce electrolytic Cr.
Downing JH et al; Chromium and Chromium Alloys. Ullmann's Encyclopedia of Industrial Chemistry 7th ed. (1999-2015). NY, NY: John Wiley & Sons. Online Posting Date: June 15, 2000
Chromium metal is produced by the reduction of Cr2O3 or the electrolysis of Cr(III) solutions. The metal can also be obtained from Cr(VI) solutions by electrolysis, but the process is less efficient and is used primarily for plating.
Downing JH et al; Chromium and Chromium Alloys. Ullmann's Encyclopedia of Industrial Chemistry 7th ed. (1999-2015). NY, NY: John Wiley & Sons. Online Posting Date: June 15, 2000
Commercial sources obtained from chrome ore, chromite (FeO.Cr2O3).
O'Neil, M.J. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. Cambridge, UK: Royal Society of Chemistry, 2013., p. 398
Chromium oxide + aluminum (reduction); chromium oxide + metallurgical coke (Simplex process); ferrochrome + sulfuric acid + ammonium sulfate (Elkem process)
Ashford, R.D. Ashford's Dictionary of Industrial Chemicals. London, England: Wavelength Publications Ltd., 1994., p. 219

10.3 Formulations / Preparations

Chromium metal is available in the USA as electrolytic chromium (99.5% Cr), aluminothermic chromium (98.5% Cr) & ductile chromium (99.99% Cr).
IARC. Monographs on the Evaluation of the Carcinogenic Risk of Chemicals to Humans. Geneva: World Health Organization, International Agency for Research on Cancer, 1972-PRESENT. (Multivolume work). Available at: https://monographs.iarc.fr/ENG/Classification/index.php, p. V2 103 (1973)
Available forms: (1) chromium metal as lumps, granules, or powder; (2) high or low-carbon ferrochromium; (3) single crystals, high-purity crystals, or powder run 99.97% pure.
Lewis, R.J. Sr.; Hawley's Condensed Chemical Dictionary 15th Edition. John Wiley & Sons, Inc. New York, NY 2007., p. 299

10.4 Consumption Patterns

STAINLESS & HEAT RESISTING STEELS, 71.4%; FULL ALLOY STEEL, 15.2%; HIGH STRENGTH, LOW ALLOY & ELECTRIC STEELS, 3.1%; SUPERALLOYS, 2.8%; CAST IRONS, 2.6%; CARBON STEEL, 2.4%; OTHER, 2.5% (1982, CHROMIUM & CHROMIUM ALLOY USE)
SRI
Stainless and heat resisting steel, 76%; full alloy steel, 11%; super alloys, 4% and other alloys, 9% (1986) /Consumption of chromium ferroalloys, metal, and other chromium containing materials by end use/
BUREAU OF MINES. MINERAL COMMODITY SUMMARIES 1987 p.34
Ferrous alloys, mainly stainless steels, account for most of the consumption.
Downing JH et al; Chromium and Chromium Alloys. Ullmann's Encyclopedia of Industrial Chemistry 7th ed. (1999-2015). NY, NY: John Wiley & Sons. Online Posting Date: June 15, 2000

Chromium: Consumption: Reported

Table: Data in thousand metric tons of chromium content

Year
2010
Consumption, Reported (includes recycling)
396
Consumption, Apparent (includes recycling)
384
Year
2011
Consumption, Reported (includes recycling)
400
Consumption, Apparent (includes recycling)
450
Year
2012
Consumption, Reported (includes recycling)
401
Consumption, Apparent (includes recycling)
471
Year
2013
Consumption, Reported (includes recycling)
402
Consumption, Apparent (includes recycling)
400
Year
2014 (estimated)
Consumption, Reported (includes recycling)
414
Consumption, Apparent (includes recycling)
560

USGS; Mineral Commodity Summaries 2015. Chromium. Available from, as of November 2, 2015: https://minerals.usgs.gov/minerals/pubs/mcs/

10.5 U.S. Production

Aggregated Product Volume

2019: 100,000,000 lb - <1,000,000,000 lb

2018: 250,000,000 - <500,000,000 lb

2017: 500,000,000 - <750,000,000 lb

2016: 100,000,000 lb - <1,000,000,000 lb

Non-confidential 2012 Chemical Data Reporting (CDR) information on the production and use of chemicals manufactured or imported into the United States. Chemical: Chromium. National Production Volume: 3,713,461,755 lb/yr.
USEPA/Pollution Prevention and Toxics; 2012 Chemical Data Reporting Database. Chromium (7440-47-3). Available from, as of October 26, 2015: https://java.epa.gov/oppt_chemical_search/

Chromium: Production: Recycling

Table: Data in thousand metric tons of chromium content

Year
2010
Production (Recycling)
144
Year
2011
Production (Recycling)
147
Year
2012
Production (Recycling)
146
Year
2013
Production (Recycling)
150
Year
2014 (estimated)
Production (Recycling)
155

USGS; Mineral Commodity Summaries 2015. Chromium. Available from, as of November 2, 2015: https://minerals.usgs.gov/minerals/pubs/mcs/

10.6 U.S. Imports

Chromium: Imports for consumption

Table: Data in thousand metric tons of chromium content

Year
2010
Imports for consumption
499
Year
2011
Imports for consumption
531
Year
2012
Imports for consumption
554
Year
2013
Imports for consumption
475
Year
2014 (estimated)
Imports for consumption
631

USGS; Mineral Commodity Summaries 2015. Chromium. Available from, as of November 2, 2015: https://minerals.usgs.gov/minerals/pubs/mcs/

10.7 U.S. Exports

Chromium: Exports

Table: Data in thousand metric tons of chromium content

Year
2010
Exports
274
Year
2011
Exports
232
Year
2012
Exports
234
Year
2013
Exports
235
Year
2014 (estimated)
Exports
226

USGS; Mineral Commodity Summaries 2015. Chromium. Available from, as of November 2, 2015: https://minerals.usgs.gov/minerals/pubs/mcs/

10.8 General Manufacturing Information

Industry Processing Sectors
  • Not Known or Reasonably Ascertainable
  • Primary Metal Manufacturing
  • Construction
  • Oil and Gas Drilling, Extraction, and Support activities
  • Services
  • Printing and Related Support Activities
  • Utilities
  • Computer and Electronic Product Manufacturing
  • Fabricated Metal Product Manufacturing
  • Other (requires additional information)
  • Machinery Manufacturing
  • Electrical Equipment, Appliance, and Component Manufacturing
  • All Other Basic Inorganic Chemical Manufacturing
  • Transportation Equipment Manufacturing
  • Wholesale and Retail Trade
  • Miscellaneous Manufacturing
EPA TSCA Commercial Activity Status
Chromium: ACTIVE

11 Identification

11.1 NIOSH Analytical Methods

12 Safety and Hazards

12.1 Hazards Identification

12.1.1 GHS Classification

1 of 4
View All
Note
Pictograms displayed are for 50.4% (1201 of 2381) of reports that indicate hazard statements. This chemical does not meet GHS hazard criteria for 49.6% (1180 of 2381) of reports.
Pictogram(s)
Irritant
Health Hazard
Signal
Danger
GHS Hazard Statements

H317 (20.9%): May cause an allergic skin reaction [Warning Sensitization, Skin]

H319 (19.3%): Causes serious eye irritation [Warning Serious eye damage/eye irritation]

H334 (20.5%): May cause allergy or asthma symptoms or breathing difficulties if inhaled [Danger Sensitization, respiratory]

Precautionary Statement Codes

P233, P260, P261, P264+P265, P271, P272, P280, P284, P302+P352, P304+P340, P305+P351+P338, P321, P333+P317, P337+P317, P342+P316, P362+P364, P403, and P501

(The corresponding statement to each P-code can be found at the GHS Classification page.)

ECHA C&L Notifications Summary

Aggregated GHS information provided per 2381 reports by companies from 20 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

Reported as not meeting GHS hazard criteria per 1180 of 2381 reports by companies. For more detailed information, please visit ECHA C&L website.

There are 18 notifications provided by 1201 of 2381 reports by companies with hazard statement code(s).

Information may vary between notifications depending on impurities, additives, and other factors. The percentage value in parenthesis indicates the notified classification ratio from companies that provide hazard codes. Only hazard codes with percentage values above 10% are shown.

12.1.2 Hazard Classes and Categories

Skin Sens. 1 (20.9%)

Eye Irrit. 2 (19.3%)

Resp. Sens. 1 (20.5%)

Serious eye damage/eye irritation - Category 2B

Respiratory sensitization - Category 1

Skin sensitization - Category 1

Germ cell mutagenicity - Category 2

Specific target organ toxicity - Single exposure - Category 2 (systemic toxicity), Category 3 (respiratory tract irritation)

12.1.3 Health Hazards

Excerpt from NIOSH Pocket Guide for Chromium metal:

Exposure Routes: Inhalation, ingestion, skin and/or eye contact

Symptoms: Irritation eyes, skin; lung fibrosis (histologic)

Target Organs: Eyes, skin, respiratory system (NIOSH, 2024)

12.1.4 Fire Hazards

Excerpt from ERG Guide 154 [Substances - Toxic and/or Corrosive (Non-Combustible)]:

Non-combustible, substance itself does not burn but may decompose upon heating to produce corrosive and/or toxic fumes. Some are oxidizers and may ignite combustibles (wood, paper, oil, clothing, etc.). Corrosives in contact with metals may evolve flammable hydrogen gas. Containers may explode when heated. For electric vehicles or equipment, ERG Guide 147 (lithium ion or sodium ion batteries) or ERG Guide 138 (sodium batteries) should also be consulted. (ERG, 2024)

Combustible under specific conditions.

12.1.5 Hazards Summary

Chromium is a naturally occurring element found in rocks, animals, plants, soil, and in volcanic dust and gases. Chromium is present in the environment in several different forms. The most common forms are chromium(0), chromium(III), and chromium(VI). No taste or odor is associated with chromium compounds. Chromium(III) occurs naturally in the environment and is an essential nutrient. Chromium(VI) and chromium(0) are generally produced by industrial processes. The metal chromium, which is the chromium(0) form, is used for making steel. Chromium(VI) and chromium(III) are used for chrome plating, dyes and pigments, leather tanning, and wood preserving.
Chromium occurs in the environment primarily in two valence states, trivalent chromium (Cr III) and hexavalent chromium (Cr VI). Exposure may occur from natural or industrial sources of chromium. Chromium III is much less toxic than chromium (VI). The respiratory tract is also the major target organ for chromium (III) toxicity, similar to chromium (VI). Chromium (III) is an essential element in humans. The body can detoxify some amount of chromium (VI) to chromium (III). The respiratory tract is the major target organ for chromium (VI) toxicity, for acute (short-term) and chronic (long-term) inhalation exposures. Shortness of breath, coughing, and wheezing were reported from a case of acute exposure to chromium (VI), while perforations and ulcerations of the septum, bronchitis, decreased pulmonary function, pneumonia, and other respiratory effects have been noted from chronic exposure. Human studies have clearly established that inhaled chromium (VI) is a human carcinogen, resulting in an increased risk of lung cancer. Animal studies have shown chromium (VI) to cause lung tumors via inhalation exposure.
Chromium metal and Cr(III) compounds are IARC 3 (not classifiable), while the hexavalent chromium Cr(VI) compounds are IARC 1 (human carcinogens); Water-soluble, Cr(VI) compounds have the skin designation. All Cr(VI) compounds are designated as RSEN and DSEN, meaning that they may cause asthma and allergic contact dermatitis. Kidney injury has been reported in workers exposed to hexavalent chromium compounds, but no quantitative exposure information is available. Reproductive studies of workers handling Cr(VI) compounds are inconclusive. The severe corrosive effects of Cr(VI) compounds can lead to ulceration of the skin (chrome holes) and mouth, rhinitis, and perforation of the nasal septum. [ACGIH] Among chromate production workers, virtually all studies showed excess risks of lung cancer, except for a few estimates of risks for US workers hired since exposures were lowered . . . [IARC Monograph 100C, p. 154] Compounds of Cr III do not cause chrome ulcerations and do not generally initiate allergic dermatitis without prior sensitization by Cr(VI) compounds. [ILO Encyclo: Chromium] . . .induction of sensitization by water-soluble Cr(III) compounds independently of Cr(VI) exposures cannot be ruled out. [ACGIH] 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] 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, p. 219] Humans are exposed to Cr III compounds in food with no known adverse effects. Cr III compounds are at least 500 times less toxic than Cr VI compounds. Organic Cr-containing complexes of toxicological importance have not been reported. [Nordberg, p. 717-8]
ACGIH - Documentation of the TLVs and BEIs, 7th Ed. Cincinnati: ACGIH Worldwide, 2020.
ACGIH - Documentation of the TLVs and BEIs, 7th Ed. Cincinnati: ACGIH Worldwide, 2020.
Marks - Marks JG, DeLeo VA. Contact and Occupational Dermatology, 2nd Ed. St. Louis: Mosby, 1997., p. 117-9
Frazier - Frazier LM, Hage ML (eds). Reproductive Hazards of the Workplace. New York: John Wiley & Sons, 1998.
Marks - Marks JG, DeLeo VA. Contact and Occupational Dermatology, 2nd Ed. St. Louis: Mosby, 1997.
Kanerva - Rustemeyer L, Elsner P, John SM, Maibach HI (eds). Kanerva's Occupational Dermatology, 2nd Ed. Berlin: Springer-Verlag, 2012., p. 219
Nordberg - Nordberg GF, Fowler BA, Nordberg M (eds). Handbook on the Toxicology of Metals, 4th Ed. Boston: Elsevier, 2015., p. 717-8

12.1.6 Fire Potential

... When finely divided burns rapidly if heated in flame.
Browning, E. Toxicity of Industrial Metals. 2nd ed. New York: Appleton-Century-Crofts, 1969., p. 119

12.1.7 Skin, Eye, and Respiratory Irritations

Chromium aerosols ... caused ... irritation to the upper respiratory tract. /SRP: dusts or particulates/
Waldbott GL; Health Effects of Envir Poll p.201 (1973)
Chromium causes severe nasal irritation ... .
Arena, J.M. and Drew, R.H. (eds.) Poisoning-Toxicology, Symptoms, Treatments. 5th ed. Springfield, IL: Charles C. Thomas Publisher, 1986., p. 873

12.1.8 EPA Hazardous Waste Number

D007; A waste containing chromium may or may not be characterized as a hazardous waste following testing by the Toxicity Characteristic Leaching Procedure as prescribed by the Resource Conservation and Recovery Act (RCRA) regulations.

12.2 Safety and Hazard Properties

12.2.1 Flammable Limits

Flammability
Noncombustible Solid in bulk form, but finely divided dust burns rapidly if heated in a flame.

12.2.2 Physical Dangers

Dust explosion possible if in powder or granular form, mixed with air.

12.2.3 Explosive Limits and Potential

When /dust/ is suspended in carbon dioxide atmospheres ... /it is/ ignitable and explosive ... .
Bretherick, L. Handbook of Reactive Chemical Hazards. 4th ed. Boston, MA: Butterworth-Heinemann Ltd., 1990, p. 195
Powder will explode spontaneously in air. ... May ignite or react violently with bromine pentafluoride.
Lewis, R.J. Sr. (ed) Sax's Dangerous Properties of Industrial Materials. 11th Edition. Wiley-Interscience, Wiley & Sons, Inc. Hoboken, NJ. 2004., p. 918

12.2.4 OSHA Standards

Permissible Exposure Limit: Table Z-1 8-hr Time Weighted Avg: 1 mg/cu m. /Chromium metal and insoluble salts, as Cr/
29 CFR 1910.1000 (USDOL); U.S. National Archives and Records Administration's Electronic Code of Federal Regulations. Available from, as of November 3, 2015: https://www.ecfr.gov
Permissible Exposure Limit: Table Z-1 8-hr Time Weighted Avg: 0.5 mg/cu m. /Chromium(II) compounds, as Cr/
29 CFR 1910.1000 (USDOL); U.S. National Archives and Records Administration's Electronic Code of Federal Regulations. Available from, as of November 3, 2015: https://www.ecfr.gov
Permissible Exposure Limit: Table Z-1 8-hr Time Weighted Avg: 0.5 mg/cu m. /Chromium(III) compounds, as Cr/
29 CFR 1910.1000 (USDOL); U.S. National Archives and Records Administration's Electronic Code of Federal Regulations. Available from, as of November 3, 2015: https://www.ecfr.gov
Permissible Exposure Limit: Table Z-2 Acceptable Ceiling Concentration: 1 mg/10 cu m. /Chromic acid and chromates (as CrO3)/
29 CFR 1910.1000 (USDOL); U.S. National Archives and Records Administration's Electronic Code of Federal Regulations. Available from, as of November 3, 2015: https://www.ecfr.gov

12.2.5 NIOSH Recommendations

Recommended Exposure Limit: 8-hour Time-Weighted Average: 0.5 mg Cr/cu m. /Chromium metal, chromium(II) and chromium(III) compounds/
NIOSH. NIOSH Pocket Guide to Chemical Hazards. Department of Health & Human Services, Centers for Disease Control & Prevention. National Institute for Occupational Safety & Health. DHHS (NIOSH) Publication No. 2010-168 (2010). Available from: https://www.cdc.gov/niosh/npg
Recommended Exposure Limit: 8-hour Time-Weighted Average: 0.0002 mg Cr(VI)/cu m. NIOSH considers all Cr(VI) compounds (including chromic acid, tert-butyl chromate, zinc chromate, and chromyl chloride) to be potential occupational carcinogens. /All hexavalent chromium (Cr(VI) compounds/
NIOSH. NIOSH Pocket Guide to Chemical Hazards. Department of Health & Human Services, Centers for Disease Control & Prevention. National Institute for Occupational Safety & Health. DHHS (NIOSH) Publication No. 2010-168 (2010). Available from: https://www.cdc.gov/niosh/npg
NIOSH usually recommends that occupational exposures to carcinogens be limited to the lowest feasible concentration. /Chromic acid and chromates/
NIOSH. NIOSH Pocket Guide to Chemical Hazards. Department of Health & Human Services, Centers for Disease Control & Prevention. National Institute for Occupational Safety & Health. DHHS (NIOSH) Publication No. 2010-168 (2010). Available from: https://www.cdc.gov/niosh/npg

12.3 First Aid Measures

Inhalation First Aid
Fresh air, rest.
Skin First Aid
Remove contaminated clothes. Rinse skin with plenty of water or shower.
Eye First Aid
First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then refer for medical attention.
Ingestion First Aid
Rinse mouth.

12.3.1 First Aid

EYES: First check the victim for contact lenses and remove if present. Flush victim's eyes with water or normal saline solution for 20 to 30 minutes while simultaneously calling a hospital or poison control center. Do not put any ointments, oils, or medication in the victim's eyes without specific instructions from a physician. IMMEDIATELY transport the victim after flushing eyes to a hospital even if no symptoms (such as redness or irritation) develop.

SKIN: IMMEDIATELY flood affected skin with water while removing and isolating all contaminated clothing. Gently wash all affected skin areas thoroughly with soap and water. If symptoms such as redness or irritation develop, IMMEDIATELY call a physician and be prepared to transport the victim to a hospital for treatment.

INHALATION: IMMEDIATELY leave the contaminated area; take deep breaths of fresh air. IMMEDIATELY call a physician and be prepared to transport the victim to a hospital even if no symptoms (such as wheezing, coughing, shortness of breath, or burning in the mouth, throat, or chest) develop. Provide proper respiratory protection to rescuers entering an unknown atmosphere. Whenever possible, Self-Contained Breathing Apparatus (SCBA) should be used; if not available, use a level of protection greater than or equal to that advised under Protective Clothing.

INGESTION: Some heavy metals are VERY TOXIC POISONS, especially if their salts are very soluble in water (e.g., lead, chromium, mercury, bismuth, osmium, and arsenic). IMMEDIATELY call a hospital or poison control center and locate activated charcoal, egg whites, or milk in case the medical advisor recommends administering one of them. Also locate Ipecac syrup or a glass of salt water in case the medical advisor recommends inducing vomiting. Usually, this is NOT RECOMMENDED outside of a physician's care. If advice from a physician is not readily available and the victim is conscious and not convulsing, give the victim a glass of activated charcoal slurry in water or, if this is not available, a glass of milk, or beaten egg whites and IMMEDIATELY transport victim to a hospital. If the victim is convulsing or unconscious, do not give anything by mouth, assure that the victim's airway is open and lay the victim on his/her side with the head lower than the body. DO NOT INDUCE VOMITING. IMMEDIATELY transport the victim to a hospital.

OTHER: Since this chemical is a known or suspected carcinogen you should contact a physician for advice regarding the possible long term health effects and potential recommendation for medical monitoring. Recommendations from the physician will depend upon the specific compound, its chemical, physical and toxicity properties, the exposure level, length of exposure, and the route of exposure. (NTP, 1992)

National Toxicology Program, Institute of Environmental Health Sciences, National Institutes of Health (NTP). 1992. National Toxicology Program Chemical Repository Database. Research Triangle Park, North Carolina.

(See general first aid procedures)

Eye: Irrigate immediately - If this chemical contacts the eyes, immediately wash (irrigate) the eyes with large amounts of water, occasionally lifting the lower and upper lids. Get medical attention immediately.

Skin: Soap wash - If this chemical contacts the skin, wash the contaminated skin with soap and water.

Breathing: Respiratory support

Swallow: Medical attention immediately - If this chemical has been swallowed, get medical attention immediately.

12.4 Fire Fighting

Excerpt from ERG Guide 154 [Substances - Toxic and/or Corrosive (Non-Combustible)]:

SMALL FIRE: Dry chemical, CO2 or water spray.

LARGE FIRE: Dry chemical, CO2, alcohol-resistant foam or water spray. If it can be done safely, move undamaged containers away from the area around the fire. Dike runoff from fire control for later disposal.

FIRE INVOLVING TANKS, RAIL TANK CARS OR HIGHWAY TANKS: Fight fire from maximum distance or use unmanned master stream devices or monitor nozzles. Do not get water inside containers. Cool containers with flooding quantities of water until well after fire is out. Withdraw immediately in case of rising sound from venting safety devices or discoloration of tank. ALWAYS stay away from tanks in direct contact with flames. (ERG, 2024)

In case of fire in the surroundings, use appropriate extinguishing media.

12.4.1 Fire Fighting Procedures

Use water spray, alcohol-resistant foam, dry chemical or carbon dioxide. Wear self-contained breathing apparatus for firefighting if necessary.
Sigma-Aldrich; Safety Data Sheet for Chromium. Product Number: 374849, Version 4.8 (Revision Date 02/27/2015). Available from, as of October 19, 2015: https://www.sigmaaldrich.com/safety-center.html
Respiratory protection from chromium metal and insoluble chromium salts while fighting fires: self-contained breathing apparatus with a full facepiece operated in pressure-demand or other positive pressure mode. /Chromium metal and insoluble chromium salts/
Mackison, F. W., R. S. Stricoff, and L. J. Partridge, Jr. (eds.). NIOSH/OSHA - Occupational Health Guidelines for Chemical Hazards. DHHS(NIOSH) Publication No. 81-123 (3 VOLS). Washington, DC: U.S. Government Printing Office, Jan. 1981., p. 6

12.4.2 Firefighting Hazards

Chromium oxides
Sigma-Aldrich; Safety Data Sheet for Chromium. Product Number: 374849, Version 4.8 (Revision Date 02/27/2015). Available from, as of October 19, 2015: https://www.sigmaaldrich.com/safety-center.html

12.5 Accidental Release Measures

12.5.1 Isolation and Evacuation

Excerpt from ERG Guide 154 [Substances - Toxic and/or Corrosive (Non-Combustible)]:

IMMEDIATE PRECAUTIONARY MEASURE: Isolate spill or leak area in all directions for at least 50 meters (150 feet) for liquids and at least 25 meters (75 feet) for solids.

SPILL: Increase the immediate precautionary measure distance, in the downwind direction, as necessary.

FIRE: If tank, rail tank car or highway tank is involved in a fire, ISOLATE for 800 meters (1/2 mile) in all directions; also, consider initial evacuation for 800 meters (1/2 mile) in all directions. (ERG, 2024)

12.5.2 Spillage Disposal

Personal protection: particulate filter respirator adapted to the airborne concentration of the substance. Sweep spilled substance into covered containers. If appropriate, moisten first to prevent dusting.

12.5.3 Cleanup Methods

Collect spilled material in the most convenient & safe manner & deposit in sealed containers for reclamation or for disposal in a secured sanitary landfill. Liq containing chromium metal or insoluble chromium salts should be absorbed in vermiculite, dry sand, earth, or similar material.
Prager, J.C. Environmental Contaminant Reference Databook Volume 1. New York, NY: Van Nostrand Reinhold, 1995., p. 477
If chromium metal or insoluble chromium salts are spilled, the following steps should be taken: 1. Remove all ignition sources where metallic chromium has been spilled. 2. Ventilate area of spill. 3. Collect spilled material in the most convenient and safe manner and deposit in sealed containers for reclamation or for disposal in a secured sanitary landfill. Liquid containing chromium metal or insoluble chromium salts should be absorbed in vermiculite, dry sand, earth, or a similar material. /Chromium metal and insoluble chromium salts/
Mackison, F. W., R. S. Stricoff, and L. J. Partridge, Jr. (eds.). NIOSH/OSHA - Occupational Health Guidelines for Chemical Hazards. DHHS(NIOSH) Publication No. 81-123 (3 VOLS). Washington, DC: U.S. Government Printing Office, Jan. 1981., p. 4
ACCIDENTAL RELEASE MEASURES; Personal precautions, protective equipment and emergency procedures: Avoid dust formation. Avoid breathing vapors, mist or gas. Ensure adequate ventilation. Evacuate personnel to safe areas. Environmental precautions: Prevent further leakage or spillage if safe to do so. Do not let product enter drains. Discharge into the environment must be avoided. Methods and materials for containment and cleaning up: Pick up and arrange disposal without creating dust. Sweep up and shovel. Keep in suitable, closed containers for disposal.
Sigma-Aldrich; Safety Data Sheet for Chromium. Product Number: 374849, Version 4.8 (Revision Date 02/27/2015). Available from, as of October 19, 2015: https://www.sigmaaldrich.com/safety-center.html
If chromium metal or insoluble chromium salts are spilled, the following steps should be taken: 1. Remove all ignition sources where metallic chromium has been spilled. 2. Ventilate area of spill. 3) Collect spilled material in the most convenient and safe manner and deposit in sealed containers for reclamation or for disposal in a secured sanitary landfill. Liquid containing chromium metal or insoluble chromium salts should be absorbed in vermiculite, dry sand, earth, or a similar material. /Chromium metal and insoluble chromium salts/
Mackison, F. W., R. S. Stricoff, and L. J. Partridge, Jr. (eds.). NIOSH/OSHA - Occupational Health Guidelines for Chemical Hazards. DHHS(NIOSH) Publication No. 81-123 (3 VOLS). Washington, DC: U.S. Government Printing Office, Jan. 1981., p. 4

12.5.4 Disposal Methods

Generators of waste (equal to or greater than 100 kg/mo) containing this contaminant, EPA hazardous waste number D007, must conform with USEPA regulations in storage, transportation, treatment and disposal of waste. /Chromium/
40 CFR 240-280, 300-306, 702-799 (USEPA); U.S. National Archives and Records Administration's Electronic Code of Federal Regulations. Available from, as of November 24, 2015: https://www.ecfr.gov
Precipitation is the preferred treatment process for removing toxic heavy metals from electroplating waters. Precipitation processes include hydroxide, lime and/or sulfide treatment. Chemical reduction is used to treat complex metals such as nickel, copper, hexavalent chromium waste, soluble lead, silver, metal containing cyanide, and mercury. Adsorption has shown potential for treating and polishing aqueous metal bearing wastes. Activated carbon, activated alumina, and iron filings are all applicable adsorbents. Alkaline chlorination and incineration are effective cyanide destruction treatments. Evaporation, ion-exchange, reverse osmosis, electrodialysis, and electrolytic recovery are waste reduction and recovery techniques applicable to metal bearing hazardous streams.
Grosse DW; 12th Annual Research Symposium on Land Disposal, Remedial Action, Incineration, and Treatment of Hazardous Wastes (1986)
Waste disposal method: Chromium metal or insoluble chromium salts may be disposed of in sealed containers in a secured sanitary landfill. /Chromium metal and insoluble chromium salts/
Mackison, F. W., R. S. Stricoff, and L. J. Partridge, Jr. (eds.). NIOSH/OSHA - Occupational Health Guidelines for Chemical Hazards. DHHS(NIOSH) Publication No. 81-123 (3 VOLS). Washington, DC: U.S. Government Printing Office, Jan. 1981., p. 4
Product: Offer surplus and non-recyclable solutions to a licensed disposal company. Contaminated packaging: Dispose of as unused product.
Sigma-Aldrich; Safety Data Sheet for Chromium. Product Number: 374849, Version 4.8 (Revision Date 02/27/2015). Available from, as of October 19, 2015: https://www.sigmaaldrich.com/safety-center.html
For more Disposal Methods (Complete) data for CHROMIUM, ELEMENTAL (10 total), please visit the HSDB record page.

12.5.5 Preventive Measures

Daily washing of the inside of the nose combined with covering the nasal septum with zinc or barium ointment should be sufficient to avoid ulcerations and perforation of the septum.
Friberg, L., Nordberg, G.F., Kessler, E. and Vouk, V.B. (eds). Handbook of the Toxicology of Metals. 2nd ed. Vols I, II.: Amsterdam: Elsevier Science Publishers B.V., 1986., p. V2 205
SRP: Local exhaust ventilation should be applied wherever there is an incidence of point source emissions or dispersion of regulated contaminants in the work area. Ventilation control of the contaminant as close to its point of generation is both the most economical and safest method to minimize personnel exposure to airborne contaminants. Ensure that the local ventilation moves the contaminant away from the worker.
Provide appropriate exhaust ventilation at places where dust is formed.
Sigma-Aldrich; Safety Data Sheet for Chromium. Product Number: 374849, Version 4.8 (Revision Date 02/27/2015). Available from, as of October 19, 2015: https://www.sigmaaldrich.com/safety-center.html
Gloves must be inspected prior to use. Use proper glove removal technique (without touching glove's outer surface) to avoid skin contact with this product. Dispose of contaminated gloves after use in accordance with applicable laws and good laboratory practices. Wash and dry hands.
Sigma-Aldrich; Safety Data Sheet for Chromium. Product Number: 374849, Version 4.8 (Revision Date 02/27/2015). Available from, as of October 19, 2015: https://www.sigmaaldrich.com/safety-center.html
For more Preventive Measures (Complete) data for CHROMIUM, ELEMENTAL (9 total), please visit the HSDB record page.

12.6 Handling and Storage

12.6.1 Nonfire Spill Response

SMALL SPILLS AND LEAKAGE: If you spill this chemical, dampen the solid spill material with 5% ammonium hydroxide, then transfer the dampened material to a suitable container. Use absorbent paper dampened with 5% ammonium hydroxide to pick up any remaining material. Your contaminated clothing and the absorbent paper should be sealed in a vapor-tight plastic bag for eventual disposal. Wash all contaminated surfaces with 5% ammonium hydroxide followed by washing with a strong soap and water solution. Do not reenter the contaminated area until the Safety Officer (or other responsible person) has verified that the area has been properly cleaned.

STORAGE PRECAUTIONS: You should store this material in a refrigerator. (NTP, 1992)

National Toxicology Program, Institute of Environmental Health Sciences, National Institutes of Health (NTP). 1992. National Toxicology Program Chemical Repository Database. Research Triangle Park, North Carolina.

12.6.2 Storage Conditions

Keep container tightly closed in a dry and well-ventilated place.
Sigma-Aldrich; Safety Data Sheet for Chromium. Product Number: 374849, Version 4.8 (Revision Date 02/27/2015). Available from, as of October 19, 2015: https://www.sigmaaldrich.com/safety-center.html

12.7 Exposure Control and Personal Protection

Exposure Summary

Biological Exposure Indices (BEI) [ACGIH] - 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)

TIH (Toxic Inhalation Hazard) - Term used to describe gases and volatile liquids that are toxic when inhaled. Some are TIH materials themselves, e.g., chlorine, and some release TIH gases when spilled in water, e.g., chlorosilanes. [ERG 2016].

ACGIH - Documentation of the TLVs and BEIs, 7th Ed. Cincinnati: ACGIH Worldwide, 2020.

12.7.2 Permissible Exposure Limit (PEL)

1.0 [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)
PEL-TWA (8-Hour Time Weighted Average)
1 mg/m³
PEL-TWA (8-Hour Time Weighted Average)
0.5 mg/m³
TWA 1 mg/m3 See Appendix C [*Note: The PEL also applies to insoluble chromium salts.]

12.7.3 Immediately Dangerous to Life or Health (IDLH)

250 mg Cr/m3 (NIOSH, 2024)

250.0 [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.

250 mg/cu m (as Cr)
NIOSH. NIOSH Pocket Guide to Chemical Hazards. Department of Health & Human Services, Centers for Disease Control & Prevention. National Institute for Occupational Safety & Health. DHHS (NIOSH) Publication No. 2010-168 (2010). Available from: https://www.cdc.gov/niosh/npg
250 mg/cu m (as Cr(II)). /Chromium(II) compounds (as Cr)/
NIOSH. NIOSH Pocket Guide to Chemical Hazards. Department of Health & Human Services, Centers for Disease Control & Prevention. National Institute for Occupational Safety & Health. DHHS (NIOSH) Publication No. 2010-168 (2010). Available from: https://www.cdc.gov/niosh/npg
25 mg/cu m (as Cr(III)). /Chromium(III) compounds (as Cr)/
NIOSH. NIOSH Pocket Guide to Chemical Hazards. Department of Health & Human Services, Centers for Disease Control & Prevention. National Institute for Occupational Safety & Health. DHHS (NIOSH) Publication No. 2010-168 (2010). Available from: https://www.cdc.gov/niosh/npg
15 mg/cu m (as Cr(VI)). /Chromic acid and chromates/
NIOSH. NIOSH Pocket Guide to Chemical Hazards. Department of Health & Human Services, Centers for Disease Control & Prevention. National Institute for Occupational Safety & Health. DHHS (NIOSH) Publication No. 2010-168 (2010). Available from: https://www.cdc.gov/niosh/npg
NIOSH considers chromic acid and chromates to be potential occupational carcinogens. /Chromic acid and chromates/
NIOSH. NIOSH Pocket Guide to Chemical Hazards. Department of Health & Human Services, Centers for Disease Control & Prevention. National Institute for Occupational Safety & Health. DHHS (NIOSH) Publication No. 2010-168 (2010). Available from: https://www.cdc.gov/niosh/npg
250 mg/m³

250 mg/m3 (as Cr)

See: 7440473

12.7.4 Threshold Limit Values (TLV)

0.5 [mg/m3], as Cr(0), inhalable particulate matter, 0.003 mg/m3, (Cr(III), inhalable particulate matter), 0.0002 mg/m3, as Cr(VI), inhalable particulate matter
TLV-STEL
0.0005 [mg/m3], as Cr(VI), inhalable particulate matter
8 hr Time Weighted Avg (TWA): 0.5 mg/cu m. /Chromium and Cr(III) inorganic compounds, as Cr/
American Conference of Governmental Industrial Hygienists TLVs and BEIs. Threshold Limit Values for Chemical Substances and Physical Agents and Biological Exposure Indices. Cincinnati, OH 2015, p. 21
American Conference of Governmental Industrial Hygienists TLVs and BEIs. Threshold Limit Values for Chemical Substances and Physical Agents and Biological Exposure Indices. Cincinnati, OH 2016, p. 21
A4; Not classifiable as a human carcinogen. /Chromium and Cr(III) inorganic compounds, as Cr/
American Conference of Governmental Industrial Hygienists TLVs and BEIs. Threshold Limit Values for Chemical Substances and Physical Agents and Biological Exposure Indices. Cincinnati, OH 2015, p. 21
Excursion Limit Recommendation: Excursions in worker exposure levels may exceed 3 times the TLV-TWA for no more than a total of 30 minutes during a work day, and under no circumstances should they exceed 5 times the TLV-TWA, provided that the TLV-TWA is not exceeded. /Chromium and Cr(III) inorganic compounds, as Cr/
American Conference of Governmental Industrial Hygienists TLVs and BEIs. Threshold Limit Values for Chemical Substances and Physical Agents and Biological Exposure Indices. Cincinnati, OH 2015, p. 5
For more Threshold Limit Values (TLV) (Complete) data for CHROMIUM, ELEMENTAL (14 total), please visit the HSDB record page.
(as Cr(0), inhalable fraction): 0.5 mg/m
TLV-TWA (Time Weighted Average)
0.5 mg/m³ (inhalable particulate matter) [2017]
TLV-TWA (Time Weighted Average)
0.003 mg/m³ (inhalable particulate matter) [2017]

12.7.5 Inhalation Risk

A harmful concentration of airborne particles can be reached quickly when dispersed.

12.7.6 Effects of Short Term Exposure

May cause mechanical irritation to the eyes and respiratory tract.

12.7.7 Personal Protective Equipment (PPE)

Excerpt from NIOSH Pocket Guide for Chromium metal:

Skin: No recommendation is made specifying the need for personal protective equipment for the body.

Eyes: No recommendation is made specifying the need for eye protection.

Wash skin: No recommendation is made specifying the need for washing the substance from the skin (either immediately or at the end of the work shift).

Remove: No recommendation is made specifying the need for removing clothing that becomes wet or contaminated.

Change: No recommendation is made specifying the need for the worker to change clothing after the workshift. (NIOSH, 2024)

Gloves or rubber coats protect against chrome ulceration of the skin.
Nat'l Research Council Canada; Effects of Chromium in the Canadian Envir p.115 (1976) NRCC No.15017
Respirator Recommendations: Up to 2.5 mg/cu m:
Assigned Protection Factor (APF)
APF = 5
Respirator Recommendations
Any quarter-mask respirator. Substance reported to cause eye irritation or damage; may require eye protection.
NIOSH. NIOSH Pocket Guide to Chemical Hazards. Department of Health & Human Services, Centers for Disease Control & Prevention. National Institute for Occupational Safety & Health. DHHS (NIOSH) Publication No. 2010-168 (2010). Available from: https://www.cdc.gov/niosh/npg
Respirator Recommendations: Up to 5 mg/cu m:
Assigned Protection Factor (APF)
APF = 10
Respirator Recommendations
Any particulate respirator equipped with an N95, R95, or P95 filter (including N95, R95, and P95 filtering facepieces) except quarter-mask respirators. The following filters may also be used: N99, R99, P99, N100, R100, P100. Substance reported to cause eye irritation or damage; may require eye protection.
Assigned Protection Factor (APF)
APF = 10
Respirator Recommendations
Any supplied-air respirator. Substance reported to cause eye irritation or damage; may require eye protection.
NIOSH. NIOSH Pocket Guide to Chemical Hazards. Department of Health & Human Services, Centers for Disease Control & Prevention. National Institute for Occupational Safety & Health. DHHS (NIOSH) Publication No. 2010-168 (2010). Available from: https://www.cdc.gov/niosh/npg
Respirator Recommendations: Up to 12.5 mg/cu m:
Assigned Protection Factor (APF)
APF = 25
Respirator Recommendations
Any supplied-air respirator operated in a continuous-flow mode. Substance reported to cause eye irritation or damage; may require eye protection.
Assigned Protection Factor (APF)
APF = 25
Respirator Recommendations
Any powered, air-purifying respirator with a high-efficiency particulate filter. Substance reported to cause eye irritation or damage; may require eye protection.
NIOSH. NIOSH Pocket Guide to Chemical Hazards. Department of Health & Human Services, Centers for Disease Control & Prevention. National Institute for Occupational Safety & Health. DHHS (NIOSH) Publication No. 2010-168 (2010). Available from: https://www.cdc.gov/niosh/npg
For more Personal Protective Equipment (PPE) (Complete) data for CHROMIUM, ELEMENTAL (12 total), please visit the HSDB record page.

(See personal protection and sanitation codes)

Skin: No recommendation

Eyes: No recommendation

Wash skin: No recommendation

Remove: No recommendation

Change: No recommendation

12.7.8 Respirator Recommendations

NIOSH

Up to 2.5 mg/m3 :

(APF = 5) Any quarter-mask respirator.

Click here for information on selection of N, R, or P filters.*

Up to 5 mg/m3 :

(APF = 10) Any particulate respirator equipped with an N95, R95, or P95 filter (including N95, R95, and P95 filtering facepieces) except quarter-mask respirators. The following filters may also be used: N99, R99, P99, N100, R100, P100.

Click here for information on selection of N, R, or P filters.*

(APF = 10) Any supplied-air respirator*

Up to 12.5 mg/m3 :

(APF = 25) Any supplied-air respirator operated in a continuous-flow mode*

(APF = 25) Any powered, air-purifying respirator with a high-efficiency particulate filter.*

Up to 25 mg/m3 :

(APF = 50) Any air-purifying, full-facepiece respirator with an N100, R100, or P100 filter.

Click here for information on selection of N, R, or P filters.

(APF = 50) Any powered, air-purifying respirator with a tight-fitting facepiece and a high-efficiency particulate filter*

(APF = 50) Any self-contained breathing apparatus with a full facepiece

(APF = 50) Any supplied-air respirator with a full facepiece

Up to 250 mg/m3 :

(APF = 2000) Any supplied-air respirator that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode

Emergency or planned entry into unknown concentrations or IDLH conditions:

(APF = 10,000) Any self-contained breathing apparatus that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode

(APF = 10,000) Any supplied-air respirator that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode in combination with an auxiliary self-contained positive-pressure breathing apparatus

Escape:

(APF = 50) Any air-purifying, full-facepiece respirator with an N100, R100, or P100 filter.

Click here for information on selection of N, R, or P filters.

Any appropriate escape-type, self-contained breathing apparatus

Important additional information about respirator selection

12.7.9 Preventions

Fire Prevention
If powder: NO open flames Closed system, dust explosion-proof electrical equipment and lighting. Prevent deposition of dust.
Exposure Prevention
PREVENT DISPERSION OF DUST!
Inhalation Prevention
Use local exhaust or breathing protection.
Skin Prevention
Protective gloves.
Eye Prevention
Wear safety goggles.
Ingestion Prevention
Do not eat, drink, or smoke during work.

12.8 Stability and Reactivity

12.8.1 Air and Water Reactions

May be pyrophoric, as dust. Insoluble in water.

12.8.2 Reactive Group

Metals, Elemental and Powder, Active

12.8.3 Reactivity Alerts

Pyrophoric

12.8.4 Reactivity Profile

CHROMIUM reacts violently with NH4NO3, N2O2, Li, NO, KClO3, SO2 (NTP, 1992). Metal dusts when suspended in atmospheres of carbon dioxide may ignite and explode.
National Toxicology Program, Institute of Environmental Health Sciences, National Institutes of Health (NTP). 1992. National Toxicology Program Chemical Repository Database. Research Triangle Park, North Carolina.

12.8.5 Hazardous Reactivities and Incompatibilities

Molten lithium at 180 °C attacks vanadium, beryllium, or chromium severely.
National Fire Protection Association; Fire Protection Guide to Hazardous Materials. 14TH Edition, Quincy, MA 2010, p. 491-110
Reacts with dilute HCl /hydrochloric acid/, H2SO4 /sulfuric acid/ ... .
O'Neil, M.J. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. Cambridge, UK: Royal Society of Chemistry, 2013., p. 398
Powder will explode spontaneously in air. Ignites & is potentially explosive in atmospheres of carbon dioxide. Violent or explosive reaction when heated with ammonium nitrate. May ignite or react violently with bromine pentafluoride. Incandescent reaction with nitrogen oxide or sulfur dioxide.
Lewis, R.J. Sax's Dangerous Properties of Industrial Materials. 9th ed. Volumes 1-3. New York, NY: Van Nostrand Reinhold, 1996., p. 853
Chromium is attacked vigorously by fused potassium chlorate, producing vivid incandescence. Pyrophoric chromium unites with sulfur dioxide with incandescence. Pyrophoric chromium unites with nitric oxide with incandescence.
National Fire Protection Association; Fire Protection Guide to Hazardous Materials. 14TH Edition, Quincy, MA 2010, p. 491-63
For more Hazardous Reactivities and Incompatibilities (Complete) data for CHROMIUM, ELEMENTAL (7 total), please visit the HSDB record page.

12.9 Transport Information

12.9.1 DOT Label

Corrosive

12.10 Regulatory Information

The Australian Inventory of Industrial Chemicals
Chemical: Chromium
REACH Registered Substance
New Zealand EPA Inventory of Chemical Status
Chromium: Does not have an individual approval but may be used under an appropriate group standard

12.10.1 Atmospheric Standards

... Substances for which a Federal Register notice has been published that included consideration of the serious health effects, including cancer, from ambient air exposure to the substance. Chromium is included on this list. /Chromium/
40 CFR 61.01(b) (USEPA); U.S. National Archives and Records Administration's Electronic Code of Federal Regulations. Available from, as of November 3, 2015: https://www.ecfr.gov
Listed as a hazardous air pollutant (HAP) generally known or suspected to cause serious health problems. The Clean Air Act, as amended in 1990, directs EPA to set standards requiring major sources to sharply reduce routine emissions of toxic pollutants. EPA is required to establish and phase in specific performance based standards for all air emission sources that emit one or more of the listed pollutants. Chromium compounds is included on this list. /Chromium compounds/
Clean Air Act as amended in 1990, Sect. 112 (b) (1) Public Law 101-549 Nov. 15, 1990

12.10.2 Federal Drinking Water Standards

Maximum contaminant level for inorganic contaminants: Contaminant: Chromium; MCL 0.1 mg/L. /Chromium/
40 CFR 141.62; U.S. National Archives and Records Administration's Electronic Code of Federal Regulations. Available from, as of August 18, 2016: https://www.ecfr.gov
EPA 100 ug/L
USEPA/Office of Water; Federal-State Toxicology and Risk Analysis Committee (FSTRAC). Summary of State and Federal Drinking Water Standards and Guidelines (11/93) To Present

12.10.3 Federal Drinking Water Guidelines

Maximum contaminant level goal for inorganic contaminants: Contaminant: Chromium; MCLG 0.1 mg/L. /Chromium/
40 CFR 141.51 (USEPA); U.S. National Archives and Records Administration's Electronic Code of Federal Regulations. Available from, as of August 18, 2016: https://www.ecfr.gov
EPA 100 ug/L
USEPA/Office of Water; Federal-State Toxicology and Risk Analysis Committee (FSTRAC). Summary of State and Federal Drinking Water Standards and Guidelines (11/93) To Present

12.10.4 State Drinking Water Standards

(CA) CALIFORNIA 50 ug/L
USEPA/Office of Water; Federal-State Toxicology and Risk Analysis Committee (FSTRAC). Summary of State and Federal Drinking Water Standards and Guidelines (11/93) To Present
(CA) CALIFORNIA 10 ug/L /Hexavalent Chromium/
USEPA/Office of Water; Federal-State Toxicology and Risk Analysis Committee (FSTRAC). Summary of State and Federal Drinking Water Standards and Guidelines (11/93) To Present

12.10.5 State Drinking Water Guidelines

(AZ) ARIZONA 120 ug/L
USEPA/Office of Water; Federal-State Toxicology and Risk Analysis Committee (FSTRAC). Summary of State and Federal Drinking Water Standards and Guidelines (11/93) To Present
(MN) MINNESOTA 100 ug/L
USEPA/Office of Water; Federal-State Toxicology and Risk Analysis Committee (FSTRAC). Summary of State and Federal Drinking Water Standards and Guidelines (11/93) To Present

12.10.6 Clean Water Act Requirements

Toxic pollutant designated pursuant to section 307(a)(1) of the Federal Water Pollution Control Act and is subject to effluent limitations. /Chromium and compounds/
40 CFR 401.15 (USEPA); U.S. National Archives and Records Administration's Electronic Code of Federal Regulations. Available from, as of November 3, 2015: https://www.ecfr.gov

12.10.7 CERCLA Reportable Quantities

Persons in charge of vessels or facilities are required to notify the National Response Center (NRC) immediately, when there is a release of this designated hazardous substance, in an amount equal to or greater than its reportable quantity of 5000 lb or 2270 kg. The toll free number of the NRC is (800) 424-8802. The rule for determining when notification is required is stated in 40 CFR 302.4 (section IV. D.3.b). ... No reporting of releases of this hazardous substance is required if the diameter of the pieces of the solid metal released is larger than 100 micrometers (0.004 inches).
40 CFR 302.4 (USEPA); U.S. National Archives and Records Administration's Electronic Code of Federal Regulations. Available from, as of November 3, 2015: https://www.ecfr.gov

12.10.8 RCRA Requirements

D007; A solid waste containing chromium may or may not become characterized as a hazardous waste when subjected to the Toxicity Characteristic Leaching Procedure listed in 40 CFR 261.24, and if so characterized, must be managed as a hazardous waste. /Chromium/
40 CFR 261.24 (USEPA); U.S. National Archives and Records Administration's Electronic Code of Federal Regulations. Available from, as of August 18, 2016: https://www.ecfr.gov

12.11 Other Safety Information

Chemical Assessment
IMAP assessments - Chromium: Human health tier I assessment

12.11.1 Special Reports

ATSDR; Toxicological Profile for Chromium (September, 2012)[ATSDR; Toxicological Profile for Chromium (September, 2012); Available from, as of October, 27, 2015: http://www.atsdr.cdc.gov/toxprofiles/tp7.pdf]

13 Toxicity

13.1 Toxicological Information

13.1.1 Toxicity Summary

IDENTIFICATION AND USE: Chromium elemental (Cr) is a steel-gray, lustrous metal. It is used in maufacturing of chrome-steel or chrome-nickel-steel alloys (stainless steel), nonferrous alloys, heat resistant bricks for refractory furnaces. This helps greatly increase strength, hardness and resistance of metals to abrasion, corrosion and oxidation. It is also used for chrome plating of other metals; leather tanning; as pigment and mordant and as a wood preservative. In medicine and laboratory research (51)Cr is used as a diagnostic aid. HUMAN EXPOSURE AND TOXICITY: Human exposure to Cr is increasing due to its use in Metal-on-metal (MOM) total hip arthroplasties. Metal-on-metal arthroplasty may lead to elevated blood Cr and cobalt (Co) levels. Cases of hypersensitivity to Cr and Co have been reported in such patients. Also both circulating-free-DNA and 8-hydroxydeoxyguanosine showed a tendency to increase in male patients. However, CoCr hip implants appear to be nongenotoxic. In electric welders exposed to Cr, a significant correlation was found between the frequency of sister chromatid exchanges and individual DNA strand breakage versus the concentration of Cr in the urine. ANIMAL STUDIES: Rats (25 total) were given 6 weekly iv injections of 0.18 mL of a 0.05% suspension of chromium powder; round cell sarcomas were found in 4 rats; 1 rat had hemangioma; 2 rats had papillary adenomas of the lung, and one rat showed extensive squamous cell carcinomatous changes. Metallic Cr was assayed for the ability to induce cell transformation (anchorage-independent growth) in Syrian hamster fibroblasts. Although chromium particles were phagocytized by cells, no significant increase in the number of cell foci growing in soft agar was observed. In male rats exposed to Cr fumes generated from powders of Cr metal by plasma flame sprayer developed significant increases in the frequencies of sister chromatid exchange and of chromosomal aberrations observed in peripheral blood lymphocytes, whereas chromosomal aberration frequencies in bone-marrow cells were unchanged. ECOTOXICITY STUDIES: Cr was toxic to naiad mollusks at 12.4 ppm. The greatest Cr toxicity risk to plants is posed in acidic sandy soil with low organic content.
Hexavalent chromium's carcinogenic effects are caused by its metabolites, pentavalent and trivalent chromium. The DNA damage may be caused by hydroxyl radicals produced during reoxidation of pentavalent chromium by hydrogen peroxide molecules present in the cell. Trivalent chromium may also form complexes with peptides, proteins, and DNA, resulting in DNA-protein crosslinks, DNA strand breaks, DNA-DNA interstrand crosslinks, chromium-DNA adducts, chromosomal aberrations and alterations in cellular signaling pathways. It has been shown to induce carcinogenesis by overstimulating cellular regulatory pathways and increasing peroxide levels by activating certain mitogen-activated protein kinases. It can also cause transcriptional repression by cross-linking histone deacetylase 1-DNA methyltransferase 1 complexes to CYP1A1 promoter chromatin, inhibiting histone modification. Chromium may increase its own toxicity by modifying metal regulatory transcription factor 1, causing the inhibition of zinc-induced metallothionein transcription. (A12, L16, A34, A35, A36)
A12: Salnikow K, Zhitkovich A: Genetic and epigenetic mechanisms in metal carcinogenesis and cocarcinogenesis: nickel, arsenic, and chromium. Chem Res Toxicol. 2008 Jan;21(1):28-44. Epub 2007 Oct 30. PMID:17970581
A34: Kim G, Yurkow EJ: Chromium induces a persistent activation of mitogen-activated protein kinases by a redox-sensitive mechanism in H4 rat hepatoma cells. Cancer Res. 1996 May 1;56(9):2045-51. PMID:8616849
A35: Schnekenburger M, Talaska G, Puga A: Chromium cross-links histone deacetylase 1-DNA methyltransferase 1 complexes to chromatin, inhibiting histone-remodeling marks critical for transcriptional activation. Mol Cell Biol. 2007 Oct;27(20):7089-101. Epub 2007 Aug 6. PMID:17682057
A36: Kimura T: [Molecular mechanism involved in chromium(VI) toxicity]. Yakugaku Zasshi. 2007 Dec;127(12):1957-65. PMID:18057785
L16: ATSDR - Agency for Toxic Substances and Disease Registry (2008). Toxicological profile for chromium. U.S. Public Health Service in collaboration with U.S. Environmental Protection Agency (EPA). http://www.atsdr.cdc.gov/toxprofiles/tp7.html

13.1.2 USGS Health-Based Screening Levels for Evaluating Water-Quality

Chemical
Chromium (Total)
USGS Parameter Code
01030
Chemical Classes
Trace element
MCL (Maximum Contaminant Levels)[μg/L]
100
Reference
Smith, C.D. and Nowell, L.H., 2024. Health-Based Screening Levels for evaluating water-quality data (3rd ed.). DOI:10.5066/F71C1TWP

13.1.3 NIOSH Toxicity Data

13.1.4 Evidence for Carcinogenicity

A4; Not classifiable as a human carcinogen. /Chromium and Cr(III) inorganic compounds/
American Conference of Governmental Industrial Hygienists TLVs and BEIs. Threshold Limit Values for Chemical Substances and Physical Agents and Biological Exposure Indices. Cincinnati, OH 2016, p. 21
Evaluation: There is inadequate evidence in humans for the carcinogenicity of metallic chromium and of chromium(III) compounds. There is inadequate evidence in experimental animals for the carcinogenicity of metallic chromium, barium chromate and chromium(III) compounds. Overall evaluation: Metallic chromium and chromium(III) compounds are not classifiable as to their carcinogenicity to humans (Group 3). /Metallic chromium and chromium(III) compounds/
IARC. Monographs on the Evaluation of the Carcinogenic Risk of Chemicals to Humans. Geneva: World Health Organization, International Agency for Research on Cancer, 1972-PRESENT. (Multivolume work). Available at: https://monographs.iarc.fr/ENG/Classification/index.php, p. V49 213 (1990)

13.1.5 Carcinogen Classification

1 of 2
IARC Carcinogenic Agent
Chromium, metallic
IARC Carcinogenic Classes
Group 3: Not classifiable as to its carcinogenicity to humans
IARC Monographs

Volume Sup 7: Overall Evaluations of Carcinogenicity: An Updating of IARC Monographs Volumes 1 to 42, 1987; 440 pages; ISBN 92-832-1411-0 (out of print)

Volume 49: (1990) Chromium, Nickel and Welding

2 of 2
Carcinogen Classification
3, not classifiable as to its carcinogenicity to humans. (L135)

13.1.6 Health Effects

Hexavalent chromium is a known carcinogen. Chronic inhalation especially has been linked to lung cancer. Hexavalent chromium has also been shown to affect reproduction and development. (A12)
A12: Salnikow K, Zhitkovich A: Genetic and epigenetic mechanisms in metal carcinogenesis and cocarcinogenesis: nickel, arsenic, and chromium. Chem Res Toxicol. 2008 Jan;21(1):28-44. Epub 2007 Oct 30. PMID:17970581

13.1.7 Exposure Routes

inhalation, ingestion, skin and/or eye contact
Oral (L16) ; inhalation (L16); dermal (L16)
L16: ATSDR - Agency for Toxic Substances and Disease Registry (2008). Toxicological profile for chromium. U.S. Public Health Service in collaboration with U.S. Environmental Protection Agency (EPA). http://www.atsdr.cdc.gov/toxprofiles/tp7.html

13.1.8 Symptoms

Inhalation Exposure
Cough.
Eye Exposure
Redness.
irritation eyes, skin; lung fibrosis (histologic)
Breathing hexavalent chromium can cause irritation to the lining of the nose, nose ulcers, runny nose, and breathing problems, such as asthma, cough, shortness of breath, or wheezing. Ingestion of hexavalent chromium causes irritation and ulcers in the stomach and small intestine, as well as anemia. Skin contact can cause skin ulcers. (L16)
L16: ATSDR - Agency for Toxic Substances and Disease Registry (2008). Toxicological profile for chromium. U.S. Public Health Service in collaboration with U.S. Environmental Protection Agency (EPA). http://www.atsdr.cdc.gov/toxprofiles/tp7.html

13.1.9 Target Organs

Cancer, Dermal (Skin), Gastrointestinal (Stomach and Intestines, part of the digestive system), Hematological (Blood Forming), Reproductive (Producing Children), Respiratory (From the Nose to the Lungs)
Eyes, skin, respiratory system

13.1.10 Adverse Effects

Occupational hepatotoxin - Secondary hepatotoxins: the potential for toxic effect in the occupational setting is based on cases of poisoning by human ingestion or animal experimentation.

Nephrotoxin - The chemical is potentially toxic to the kidneys in the occupational setting.

Dermatotoxin - Skin burns.

Skin Sensitizer - An agent that can induce an allergic reaction in the skin.

Asthma - Reversible bronchoconstriction (narrowing of bronchioles) initiated by the inhalation of irritating or allergenic agents.

IARC Carcinogen - Class 1: International Agency for Research on Cancer classifies chemicals as established human carcinogens.

NTP Carcinogen - Known to be a human carcinogen.

ACGIH Carcinogen - Confirmed Human.

13.1.11 Acute Effects

13.1.12 Minimum Risk Level

Intermediate Oral: 0.005 mg/kg/day (Hexavalent chromium) (L134) Chronic Oral: 0.001 mg/kg/day (Hexavalent chromium) (L134)
L134: ATSDR - Agency for Toxic Substances and Disease Registry (2001). Minimal Risk Levels (MRLs) for Hazardous Substances. U.S. Public Health Service in collaboration with U.S. Environmental Protection Agency (EPA). http://www.atsdr.cdc.gov/mrls/

13.1.13 Treatment

There is no known antidote for chromium poisoning. Exposure is usually handled with symptomatic treatment. (L16)
L16: ATSDR - Agency for Toxic Substances and Disease Registry (2008). Toxicological profile for chromium. U.S. Public Health Service in collaboration with U.S. Environmental Protection Agency (EPA). http://www.atsdr.cdc.gov/toxprofiles/tp7.html

13.1.14 Interactions

Humans and other organisms are exposed to multi-chemical mixtures including commonly found carcinogens such as polycyclic aromatic hydrocarbons (PAHs) and heavy metal/loids. The joint effects of these chemicals as beyond the binary mixtures have not been well characterized. In this study, we evaluated the combined genotoxicity of mixtures of PAHs and heavy metal and metalloids containing benzo(a)pyrene (B[a]P), naphthalene (Nap), phenanthrene (Phe), pyrene (Pyr), arsenic (As), cadmium (Cd) and chromium (Cr) using in vitro micronucleus (MN) test in HepG2 cells. The induction of aryl hydrocarbon receptor (AhR) by single and mixed PAHs was also measured. The results indicated that individual and mixed Nap, Phe and Pyr did not induce significant MN frequencies. PAHs mixture containing B[a]P and B[a]P alone caused significant but similar level of MN frequencies. The same pattern was found in their AhR induction. Individual metal and metalloids induced significant cytostasis and MN formation of which Cd was found the most potent inducer. Mixture of metal and metalloids caused higher frequency of MN suggesting a possible additive effect among metal and metalloids. In addition, binary mixture of metal/loids and B[a]P, namely As/B[a]P, Cd/B[a]P and Cr/B[a]P, increased MN formation. Mixture of Cd and B[a]P induced the highest level of MN. Exposure of cells to the mixture containing B[a]P and Cd/Cr/As at lower concentration (0.25 uM) resulted in significant MN frequency, the level of which was equal to that by Cd/B[a]P at 1.0 uM. The results of the study suggested that an additive effect may exist between PAHs and heavy metal/loids in a compound- and concentration-dependent manner. The compounds with highest potencies of genotoxicity in the mixture seem dominant as driving sources in the final combined genotoxicity of PAHs and heavy metal and metalloids.
Peng C et al; Mutagenesis. 30 (5): 593-602 (2015)
... Rats ... given 1 intratracheal intubation of 10 mg powder chromium alone or ... with ... methylcholanthrene & killed at ... intervals up to 12 wk. Squamous-cell carcinomas of lung developed ... in 7/12 rats given 5 mg methylcholanthrene+chromium 3/12 given 1 mg methylcholanthrene+chromium ... 3/7 given 5 mg methylcholanthrene ... 1/8 given 1 mg methylcholanthrene & in 0/12 given chromium alone. /No controls reported/
IARC. Monographs on the Evaluation of the Carcinogenic Risk of Chemicals to Humans. Geneva: World Health Organization, International Agency for Research on Cancer, 1972-PRESENT. (Multivolume work). Available at: https://monographs.iarc.fr/ENG/Classification/index.php, p. V23 256 (1980)

13.1.15 Antidote and Emergency Treatment

Immediate first aid: Ensure that adequate decontamination has been carried out. If patient is not breathing, start artificial respiration, preferably with a demand-valve resuscitator, bag-valve-mask device, or pocket mask, as trained. Perform CPR as necessary. Immediately flush contaminated eyes with gently flowing water. Do not induce vomiting. If vomiting occurs, lean patient forward or place on left side (head-down position, if possible) to maintain an open airway and prevent aspiration. Keep patient quiet and maintain normal body temperature. Obtain medical attention. /Inorganic acids and related compounds/
Currance, P.L. Clements, B., Bronstein, A.C. (Eds).; Emergency Care For Hazardous Materials Exposure. 3rd revised edition, Elsevier Mosby, St. Louis, MO 2007, p. 172-3
Basic treatment: Establish a patent airway (oropharyngeal or nasopharyngeal airway, if needed). Suction if necessary. Watch for signs of respiratory insufficiency and assist respirations if needed. Administer oxygen by nonrebreather mask at 10 to 15 L/min. Monitor for pulmonary edema and treat if necessary ... . Monitor for shock and treat if necessary ... . For eye contamination, flush eyes immediately with water. Irrigate each eye continuously with 0.9% saline (NS) during transport ... . Do not use emetics. Activated charcoal is not effective. For ingestion, rinse mouth and administer 5 mL/kg up to 200 mL of water for dilution if the patient can swallow, has a strong gag reflex, and does not drool ... . Do not attempt to neutralize because of exothermic reaction. Cover skin burns with dry, sterile dressings after decontamination ... . /Inorganic acids and related compounds/
Currance, P.L. Clements, B., Bronstein, A.C. (Eds).; Emergency Care For Hazardous Materials Exposure. 3rd revised edition, Elsevier Mosby, St. Louis, MO 2007, p. 173
Advanced treatment: Consider orotracheal or nasotracheal intubation for airway control in the patient who is unconscious, has severe pulmonary edema, or is in severe respiratory distress. Early intubation, at the first sign of upper airway obstruction, may be necessary. Positive-pressure ventilation techniques with a bag valve mask device may be beneficial. Consider drug therapy for pulmonary edema ... . Consider administering a beta agonist such as albuterol for severe bronchospasm ... . Monitor cardiac rhythm and treat arrhythmias as necessary ... . Start IV administration of D5W /SRP: "To keep open", minimal flow rate/. Use 0.9% saline (NS) or lactated Ringer's(LR) if signs of hypovolemia are present. For hypotension with signs of hypovolemia, administer fluid cautiously. Consider vasopressors if patient is hypotensive with a normal fluid volume. Watch for signs of fluid overload ... . Use proparacaine hydrochloride to assist eye irrigation ... . /Inorganic acids and related compounds/
Currance, P.L. Clements, B., Bronstein, A.C. (Eds).; Emergency Care For Hazardous Materials Exposure. 3rd revised edition, Elsevier Mosby, St. Louis, MO 2007, p. 173
Emergency and supportive measures. 1. Inhalation. Give supplemental oxygen. Treat wheezing and monitor the victim closely for delayed-onset noncardiogenic pulmonary edema. Delays in the onset of pulmonary edema of up to 72 hours have been reported after inhalation of concentrated solutions of chromic acid. 2. Ingestion. a. Diluted immediately with water. treat hemorrhagic gastroenteritis with aggressive fluid and blood replacement. Consider early endoscopy to assess the extent of esophageal or gastric injury. b. Treat hemoglobinuria resulting from hemolysis with alkaline diuresis as far rhabdomyolysis. Treat methemoglobinemia if it occurs. /Chromium/
OLSON, K.R. (Ed). Poisoning and Drug Overdose, Sixth Edition. McGraw-Hill, New York, NY 2012, p. 178
For more Antidote and Emergency Treatment (Complete) data for CHROMIUM, ELEMENTAL (7 total), please visit the HSDB record page.

13.1.16 Medical Surveillance

Tannery workers are at potential exposure to detrimental agents rendering them vulnerable to respiratory and dermal problems. Thus by performing pulmonary functions among leather tannery workers, we can decipher the effect of chromium and leather dust on lung functions and also the decline of respiratory functions with increasing years of exposure to leather dust. Pulmonary functions were assessed for 130 tannery workers and compared with the 130 unexposed office workers. Pulmonary function measurements namely FVC, FEV1, FEF25-75% and PEFR were measured using portable data logging Spirometer (KOKO Spirometer). The observed pulmonary functions of Tannery-workers in this study showed a reduction in FEV1, FVC, FEV1/FVC ratio, FEF25-75 and PEFR in relation to their predicted values and also compared to the unexposed. Smokers showed a decline in pulmonary functions compared to the nonsmokers because smoking acts as an additional risk factor in the development of respiratory illnesses. It is worthy to mention that the pulmonary function values correlate negatively with the duration of exposure to leather dust. So this study could provide base line information based upon which legal implementation of preventive measures could be undertaken.
Chandrasekaran V et al; Indian J Physiol Pharmacol. 58 (3): 206-10 (2014)

13.1.17 Human Toxicity Excerpts

/HUMAN EXPOSURE STUDIES/ Metal-on-metal (MOM) total hip arthroplasties were reintroduced because of the problems with osteolysis and aseptic loosening related to polyethylene wear of early metal-on-polyethylene (MOP) arthroplasties. The volumetric wear rate has been greatly reduced with MOM arthroplasties; however, because of nano-size wear particles, the absolute number has been greatly increased. Thus, a source of metal ion exposure with the potential to sensitize patients is present. We hypothesized that higher amounts of wear particles result in increased release of metal ions and ultimately lead to an increased incidence of metal allergy. 52 hips in 52 patients (median age 60 (51-64) years, 30 women) were randomized to either a MOM hip resurfacing system (ReCap) or a standard MOP total hip arthoplasty (Mallory Head/Exeter). Spot urine samples were collected preoperatively, postoperatively, after 3 months, and after 1, 2, and 5 years and tested with inductively coupled plasma-sector field mass spectrometry. After 5 years, hypersensitivity to metals was evaluated by patch testing and lymphocyte transformation assay. In addition, the patients answered a questionnaire about hypersensitivity. A statistically significant 10- to 20-fold increase in urinary levels of cobalt and chromium was observed throughout the entire follow-up in the MOM group. The prevalence of metal allergy was similar between groups. While we observed significantly increased levels of metal ions in the urine during the entire follow-up period, no difference in prevalence of metal allergy was observed in the MOM group. However, the effect of long-term metal exposure remains uncertain.
Gustafson K et al; Acta Orthop. 85 (4): 348-54 (2014)
/CASE REPORTS/ Metal-on-metal arthroplasty may lead to elevated blood chromium (Cr) and cobalt (Co) levels (>7 ug/L). Since carcinogenic, mutagenic, and teratogenic effects have been suggested, there is concern of pregnancy hazards for women with this condition. The 34-year-old patient has had a unilateral hip replacement for seven years. Before her pregnancy high Cr (47 ug/L) and Co (103 ug/L) blood concentrations were measured, but she did not develop any symptoms. A male infant was delivered after 41 weeks with first degree hypospadias. His levels were increased at 3 weeks of age: 14 ug/L (Cr) and 20 ug/L (Co), but decreased by 9 weeks to 6.7 ug/L (Cr) and 10.0 ug/L (Co). Maternal levels at delivery were 25 ug/L (Cr) and 51 ug/L (Co). The child was fully breast-fed and developed normally. An association between hypospadias and Cr/Co has to be considered speculative. The otherwise favorable outcome of this case may be reassuring for pregnant and breast-feeding patients with metal-on-metal hip replacements.
Oppermann M et al; Reprod Toxicol. 53: 51-3 (2015)
/CASE REPORTS/ A 75-year-old woman who had undergone hybrid metal-on-metal hip resurfacing 8 years earlier underwent revision arthroplasty because of hip, groin and lateral thigh pain. The main differential was aseptic loosening; however, serum cobalt and chromium levels were normal. Multiple imaging modalities revealed a periprosthetic, cystic soft tissue mass adjacent to the proximal femur. A large 'pseudotumor' with proximal femoral invasion was found at revision arthroplasty. We report the first finding of a 'pseudotumor' invading the proximal femur with normal metal ions following metal on metal hip resurfacing.
Krishnan H et al; BMJ Case Rep. 2015 Feb 10;2015. pii: bcr2014206368. doi: 10.1136/bcr-2014-206368.
/CASE REPORTS/ We report a series of three patients who underwent uncemented total hip arthroplasty with a modular titanium-molybdenum-zirconium-iron stem and a cobalt-chrome-molybdenum head on an ultra-high molecular weight highly cross-linked polyethylene liner bearing. All three cases subsequently developed pain and adverse reaction to metal debris, leading to revision of the implants within thirty-six months. They were subsequently found to have hypersensitivity to cobalt or chromium. However where tested, blood metal ion levels were within ...guideline limits. Corrosion was noted at the taper-trunnion junction. It is possible, that the multi alloy head-neck combination may lead to corrosion.
Kiran M et al; J Arthroplasty. 30 (2): 277-81 (2015)
For more Human Toxicity Excerpts (Complete) data for CHROMIUM, ELEMENTAL (16 total), please visit the HSDB record page.

13.1.18 Non-Human Toxicity Excerpts

/LABORATORY ANIMALS: Acute Exposure/ Chromium (Cr) containing aerosol particles with a diam of 2 um are deposited in the upper respiratory tract (nose, pharynx) while smaller particles penetrated to the trachea, bronchial tubes, & alveoli. /Chromium aerosol/
Nat'l Research Council Canada; Effects of Chromium in the Canadian Envir p.94 (1976) NRCC No.15017
/LABORATORY ANIMALS: Chronic Exposure or Carcinogenicity/ A group of 25 c57bl mice (sex unspecified) received 6 weekly /iv/ injections of 0.05 mL of 0.005% suspension of chromium (Cr) powder in gelatin-saline soln. 6 Animals lived up to 12 mo, but none to 18 mo. No tumors were observed.
IARC. Monographs on the Evaluation of the Carcinogenic Risk of Chemicals to Humans. Geneva: World Health Organization, International Agency for Research on Cancer, 1972-PRESENT. (Multivolume work). Available at: https://monographs.iarc.fr/ENG/Classification/index.php, p. V23 260 (1980)
/LABORATORY ANIMALS: Chronic Exposure or Carcinogenicity/ Of 25 male wistar rats given 6 weekly /iv/ injections of 0.18 mL of a 0.05% suspension of chromium (Cr) powder in gelatin-saline soln, 15 lived to 1 yr. Round cell sarcomas ... in 4 rats; 1 ... had hemangioma; 2 ... had papillary adenomas of the lung, one ... showed extensive squamous cell carcinomatous changes. No vehicle treated controls ...
IARC. Monographs on the Evaluation of the Carcinogenic Risk of Chemicals to Humans. Geneva: World Health Organization, International Agency for Research on Cancer, 1972-PRESENT. (Multivolume work). Available at: https://monographs.iarc.fr/ENG/Classification/index.php, p. V23 260 (1980)
/LABORATORY ANIMALS: Chronic Exposure or Carcinogenicity/ 8 Rabbits received 6 weekly iv injections of 0.5 mL/kg body wt of 5% suspension of Cr powder in gelatin saline soln in ear vein. ... Same course ... 4 MO later; & 3 yr after first ... a 3rd series of injections ... given to 3 surviving. ... 1 Of 3 ... lived 6 MO after ... developed tumor ... involving lymph node. ... No tumors ... in controls.
IARC. Monographs on the Evaluation of the Carcinogenic Risk of Chemicals to Humans. Geneva: World Health Organization, International Agency for Research on Cancer, 1972-PRESENT. (Multivolume work). Available at: https://monographs.iarc.fr/ENG/Classification/index.php, p. V23 261 (1980)
For more Non-Human Toxicity Excerpts (Complete) data for CHROMIUM, ELEMENTAL (16 total), please visit the HSDB record page.

13.1.19 Ongoing Test Status

The following link will take the user to the National Toxicology Program (NTP) Test Agent Search Results page, which tabulates all of the "Standard Toxicology & Carcinogenesis Studies", "Developmental Studies", and "Genetic Toxicity Studies" performed with this chemical. Clicking on the "Testing Status" link will take the user to the status (i.e., in review, in progress, in preparation, on test, completed, etc.) and results of all the studies that the NTP has done on this chemical.[Available from: http://ntp-apps.niehs.nih.gov/ntp_tox/index.cfm?fuseaction=ntpsearch.searchresults&searchterm=7440-47-3]

13.1.20 Protein Binding

In the blood, 95% of chromium (III) is bound to large molecular mass proteins, such as transferrin, while a small proportion associates with low molecular mass oligopeptides. Serum chromium is bound to transferrin in the beta globulin fraction.

13.2 Ecological Information

13.2.1 US EPA Regional Screening Levels for Chemical Contaminants

1 of 2
Resident Soil (mg/kg)
9.50e-01
Industrial Soil (mg/kg)
2.00e+01
Resident Air (ug/m3)
9.2e-05
Industrial Air (ug/m3)
1.10e-03
Tapwater (ug/L)
1.10e-01
MCL (ug/L)
8.0E+01(G)
Risk-based SSL (mg/kg)
2.10e-03
Oral Slope Factor (mg/kg-day)-1
1.60e-01
Inhalation Unit Risk (ug/m3)-1
1.10e-02
Chronic Oral Reference Dose (mg/kg-day)
9.00e-04
Chronic Inhalation Reference Concentration (mg/m3)
3e-05
Volatile
Volatile
Mutagen
Mutagen
Fraction of Contaminant Absorbed in Gastrointestinal Tract
0.025
2 of 2
MCL (ug/L)
1.00e+02
MCL-based SSL (mg/kg)
1.80e+05
Volatile
Volatile
Mutagen
Mutagen
Fraction of Contaminant Absorbed in Gastrointestinal Tract
0.013

13.2.2 US EPA Regional Removal Management Levels for Chemical Contaminants

1 of 2
Resident Soil (mg/kg)
3.00e+01
Industrial Soil (mg/kg)
6.30e+02
Resident Air (ug/m3)
1.20e-03
Industrial Air (ug/m3)
1.50e-02
Tapwater (ug/L)
3.50e+00
MCL (ug/L)
8.0E+01 (G)
Oral Slope Factor (mg/kg-day)-1
5.00e-01
Inhalation Unit Risk (ug/m3)-1
8.40e-02
Chronic Oral Reference Dose (mg/kg-day)
3.00e-03
Chronic Inhalation Reference Concentration (mg/m3)
1.00e-04
Volatile
Volatile
Mutagen
Mutagen
Fraction of Contaminant Absorbed in Gastrointestinal Tract
0.025
2 of 2
MCL (ug/L)
1.00e+02
Volatile
Volatile
Mutagen
Mutagen
Fraction of Contaminant Absorbed in Gastrointestinal Tract
0.013

13.2.3 Natural Pollution Sources

Chromium is found in nature only in the combined state and not as the element. ...
IARC. Monographs on the Evaluation of the Carcinogenic Risk of Chemicals to Humans. Geneva: World Health Organization, International Agency for Research on Cancer, 1972-PRESENT. (Multivolume work). Available at: https://monographs.iarc.fr/ENG/Classification/index.php, p. V2: 108 (1973)

13.2.4 Probable Routes of Human Exposure

According to the 2012 TSCA Inventory Update Reporting data, 69 reporting facilities estimate the number of persons reasonably likely to be exposed during the manufacturing, processing, or use of chromium (7440-47-3) may be as low as <10 workers up to the range of 1000-9999 workers per plant; the data may be greatly underestimated due to confidential business information (CBI) or unknown values(1).
(1) US EPA; Chemical Data Reporting (CDR). Non-confidential 2012 Chemical Data Reporting information on chemical production and use in the United States. Available from, as of Oct 19, 2015: https://java.epa.gov/oppt_chemical_search/
NIOSH (NOES Survey 1981-1983) has statistically estimated that 386,142 workers (10,433 of these are female) were potentially exposed to chromium, elemental in the US(1).
(1) NIOSH; NOES. National Occupational Exposure Survey conducted from 1981-1983. Estimated numbers of employees potentially exposed to specific agents by 2-digit standard industrial classification (SIC). Available from, as of Oct 19, 2015: https://www.cdc.gov/noes/

14 Associated Disorders and Diseases

Associated Occupational Diseases with Exposure to the Compound

Chromium, chronic toxic effect [Category: Metal Poisoning, Occupational]

Contact dermatitis, allergic [Category: Skin Disease]

Contact urticaria [Category: Skin Disease]

Asthma, occupational [Category: Airway Disease]

Lung cancer [Category: Cancer, Occupational]

Acute tubular necrosis [Category: Acute Poisoning]

15 Literature

15.1 Consolidated References

15.2 NLM Curated PubMed Citations

15.3 Thieme References

15.4 Chemical Co-Occurrences in Literature

15.5 Chemical-Gene Co-Occurrences in Literature

15.6 Chemical-Disease Co-Occurrences in Literature

16 Patents

16.1 Depositor-Supplied Patent Identifiers

16.2 Chemical Co-Occurrences in Patents

16.3 Chemical-Disease Co-Occurrences in Patents

16.4 Chemical-Gene Co-Occurrences in Patents

17 Interactions and Pathways

17.1 Protein Bound 3D Structures

17.2 Chemical-Target Interactions

17.3 Drug-Drug Interactions

17.4 Drug-Food Interactions

18 Biological Test Results

18.1 BioAssay Results

19 Taxonomy

The LOTUS Initiative for Open Natural Products Research: frozen dataset union wikidata (with metadata) | DOI:10.5281/zenodo.5794106

20 Classification

20.1 MeSH Tree

20.2 NCI Thesaurus Tree

20.3 ChEBI Ontology

20.4 FDA Pharm Classes

20.5 ChemIDplus

20.6 CAMEO Chemicals

20.7 UN GHS Classification

20.8 EPA CPDat Classification

20.9 NORMAN Suspect List Exchange Classification

20.10 EPA DSSTox Classification

20.11 International Agency for Research on Cancer (IARC) Classification

20.12 Consumer Product Information Database Classification

20.13 EPA TSCA and CDR Classification

20.14 LOTUS Tree

20.15 EPA Substance Registry Services Tree

20.16 MolGenie Organic Chemistry Ontology

21 Information Sources

  1. Agency for Toxic Substances and Disease Registry (ATSDR)
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  4. NJDOH RTK Hazardous Substance List
  5. Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
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  7. CAMEO Chemicals
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    https://cameochemicals.noaa.gov/help/reference/terms_and_conditions.htm?d_f=false
    CAMEO Chemical Reactivity Classification
    https://cameochemicals.noaa.gov/browse/react
  8. ChEBI
  9. DrugBank
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    https://www.drugbank.ca/legal/terms_of_use
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  11. LOTUS - the natural products occurrence database
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  12. NCI Thesaurus (NCIt)
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  13. RRUFF Project
  14. Toxin and Toxin Target Database (T3DB)
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    http://www.t3db.ca/downloads
  15. Athena Minerals
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    Copyright (c) ATHENA - Pierre Perroud. All Rights Reserved
  16. Handbook of Mineralogy
  17. USGS National Minerals Information Center
  18. Australian Industrial Chemicals Introduction Scheme (AICIS)
  19. CAS Common Chemistry
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    https://creativecommons.org/licenses/by-nc/4.0/
  20. ChemIDplus
    ChemIDplus Chemical Information Classification
    https://pubchem.ncbi.nlm.nih.gov/source/ChemIDplus
  21. EPA Chemical Data Reporting (CDR)
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  22. EPA Chemicals under the TSCA
    EPA TSCA Classification
    https://www.epa.gov/tsca-inventory
  23. EPA DSSTox
    CompTox Chemicals Dashboard Chemical Lists
    https://comptox.epa.gov/dashboard/chemical-lists/
  24. European Chemicals Agency (ECHA)
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  26. Hazardous Substances Data Bank (HSDB)
  27. ILO-WHO International Chemical Safety Cards (ICSCs)
  28. New Zealand Environmental Protection Authority (EPA)
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    CHROMIUM, METAL & INSOLUBLE SALTS (as Cr)
    https://www.osha.gov/chemicaldata/534
    CHROMIUM(II) COMPOUNDS (as Cr)
    https://www.osha.gov/chemicaldata/535
    CHROMIUM(III) COMPOUNDS (as Cr)
    https://www.osha.gov/chemicaldata/536
  30. Risk Assessment Information System (RAIS)
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  31. California Safe Cosmetics Program (CSCP) Product Database
  32. Consumer Product Information Database (CPID)
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    https://www.whatsinproducts.com/contents/view/1/6
    Consumer Products Category Classification
    https://www.whatsinproducts.com/
  33. ClinicalTrials.gov
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    https://clinicaltrials.gov/ct2/about-site/terms-conditions#Use
  34. Comparative Toxicogenomics Database (CTD)
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  35. Crystallography Open Database (COD)
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    https://creativecommons.org/publicdomain/zero/1.0/
  36. DailyMed
  37. EPA Chemical and Products Database (CPDat)
  38. NORMAN Suspect List Exchange
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    https://creativecommons.org/licenses/by/4.0/
    NORMAN Suspect List Exchange Classification
    https://www.norman-network.com/nds/SLE/
  39. EPA Regional Screening Levels for Chemical Contaminants at Superfund Sites
  40. NITE-CMC
  41. National Drug Code (NDC) Directory
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  42. FooDB
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    https://foodb.ca/about
  43. USGS Health-Based Screening Levels for Evaluating Water-Quality Data
  44. International Agency for Research on Cancer (IARC)
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    https://publications.iarc.fr/Terms-Of-Use
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  45. Japan Chemical Substance Dictionary (Nikkaji)
  46. KEGG
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  47. NIOSH Manual of Analytical Methods
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  48. NIPH Clinical Trials Search of Japan
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  59. NCBI
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