Carbon monoxide (CED0000940)

Record Information

Version

1.0

Creation Date

2009-03-06 18:58:15 UTC

Update Date

2026-05-14 19:10:44 UTC

Accession Number

CHEM000170

Identification

Common Name

Carbon monoxide

Class

Small Molecule

Description

Carbon monoxide belongs to the homogeneous other non-metal compounds, a class of homogeneous non-metal compounds within the inorganic compounds. It is an endogenous gas with the chemical formula CO and an average molecular weight of 28.01 g/mol. It is used industrially as a reducing agent (PMC12848130) and in the production of Polyamide. Biologically, it functions as a metabolite, human metabolite, ligand, neurotransmitter (PMC10752435), signalling molecule, neurotoxin, P450 inhibitor, mitochondrial respiratory-chain inhibitor, and antioxidant (PMC12986066). It is also applied as a vasodilator agent, biomarker, and probe. The compound is released from 60 recorded sources, including electrical and electronic equipment, household items, household cleaning and consumer products, food processing and cookware, and building and construction materials. The primary recorded exposure route is respiratory, with literature support for inhalation (PMC10186727, PMC4556249, PMC6414207, PMC7956572, PMC9712077). Carbon monoxide interacts with several protein targets. It binds to hemoglobin subunit alpha (HBA1) and hemoglobin subunit beta (HBB) to form carboxyhemoglobin (HbCO); because it has a higher affinity for hemoglobin than oxygen, this prevents the transport, delivery, and utilization of oxygen, causing anoxemia. It binds to myoglobin (MB), impairing oxygen utilization, and acts as an inhibitor of myoglobin. Additionally, it binds to cytochrome c oxidase (including subunits COX7A1, MT-CO1, MT-CO2, and MT-CO3), which interferes with aerobic metabolism and ATP synthesis, leading to anaerobic metabolism, anoxia, lactic acidosis, and cell death. Health effects associated with carbon monoxide include headache and nausea (PMC7093087), dizziness (PMC11739406), necrosis (PMC8877725), hypertension (PMC12518403), low birth weight (PMC12648132), cancer (PMC8830992, PMC9784116), increased vascular disease and stroke (PMC10946040), and increased COVID-19 (PMC11507386).

Contaminant Type

Food Toxin
Human Neurotoxin
Industrial By-product/Pollutant
Industrial/Workplace Toxin
Metabolite
Natural Compound
Organic Compound
Pollutant

Chemical Structure

MOL SDF PDB SMILES InChI

Synonyms

Value	Source
[CO]	ChEBI
C#O	ChEBI
CO	ChEBI
Monoxide, carbon	HMDB

Chemical Formula

Average Molecular Mass

28.010 g/mol

Monoisotopic Mass

27.995 g/mol

CAS Registry Number

630-08-0

IUPAC Name

Not Available

Traditional Name

Not Available

SMILES

[C-]#[O+]

InChI Identifier

InChI=1S/CO/c1-2

InChI Key

UGFAIRIUMAVXCW-UHFFFAOYSA-N

Chemical Taxonomy

Description

Belongs to the class of inorganic compounds known as homogeneous other non-metal compounds. These are inorganic non-metallic compounds in which the largest atom belongs to the class of 'other non-metals'.

Kingdom

Inorganic compounds

Super Class

Homogeneous non-metal compounds

Class

Homogeneous other non-metal compounds

Sub Class

Not Available

Direct Parent

Homogeneous other non-metal compounds

Alternative Parents

Not Available

Substituents

Homogeneous other non metal

Molecular Framework

Not Available

External Descriptors

one-carbon compound (CHEBI:17245 )
carbon oxide (CHEBI:17245 )
a small molecule (CARBON-MONOXIDE )

Biological Properties

Status

Detected and Not Quantified

Origin

Endogenous

Cellular Locations

Cytoplasm
Extracellular
Membrane

Biofluid Locations

Not Available

Tissue Locations

Not Available

Applications

Biological Roles

Chemical Roles

Organoleptic Effects

Not Available

Physical Properties

State

Gas

Appearance

Colorless gas.

Experimental Properties

Property	Value
Melting Point	−205.02 °C
Boiling Point	−191.5 °C
Solubility	1.48 mg/mL at 25°C

Predicted Properties

Property	Value	Source
Water Solubility	6.37 g/L	ALOGPS
logP	-0.06	ALOGPS
logS	-1.1	ALOGPS
Hydrogen Acceptor Count	0	ChemAxon
Hydrogen Donor Count	0	ChemAxon
Polar Surface Area	0 Å²	ChemAxon
Rotatable Bond Count	0	ChemAxon
Refractivity	26.23 m³·mol⁻¹	ChemAxon
Polarizability	1.94 Å³	ChemAxon
Number of Rings	0	ChemAxon
Bioavailability	Yes	ChemAxon
Rule of Five	No	ChemAxon
Ghose Filter	No	ChemAxon
Veber's Rule	Yes	ChemAxon
MDDR-like Rule	No	ChemAxon

Spectra

Spectrum Type	Description	Splash Key	Deposition Date	View
Predicted LC-MS/MS	Predicted LC-MS/MS Spectrum	splash10-004i-9000000000-5ea4ad4bdb0565b737bb	Not Available	View Spectrum
Predicted LC-MS/MS	Predicted LC-MS/MS Spectrum	splash10-004i-9000000000-5ea4ad4bdb0565b737bb	Not Available	View Spectrum
Predicted LC-MS/MS	Predicted LC-MS/MS Spectrum	splash10-004i-9000000000-5ea4ad4bdb0565b737bb	Not Available	View Spectrum
Predicted LC-MS/MS	Predicted LC-MS/MS Spectrum	splash10-004i-9000000000-b175ec2a41978516a72e	Not Available	View Spectrum
Predicted LC-MS/MS	Predicted LC-MS/MS Spectrum	splash10-004i-9000000000-b175ec2a41978516a72e	Not Available	View Spectrum
Predicted LC-MS/MS	Predicted LC-MS/MS Spectrum	splash10-004i-9000000000-b175ec2a41978516a72e	Not Available	View Spectrum
MS	MS Spectrum	splash10-004i-9000000000-dfbb2bd73fc3d527a340	Not Available	View Spectrum

Toxicity Profile

Mechanism of Toxicity

Carbon monoxide possesses a higher affinity than oxygen for hemoglobin, leading to the formation of carboxyhemoglobin, this provoking anoxemia. Carbon monoxide also binds to myoglobin, impairing its ability to utilize oxygen. It can also bind to cytochrome c oxidase, though with a lesser affinity than oxygen. This interferes with aerobic metabolism and efficient ATP synthesis. As a result, cells switch to anaerobic metabolism, causing anoxia, lactic acidosis, and eventual cell death. Carbon monoxide also causes endothelial cell and platelet release of nitric oxide, and the formation of oxygen free radicals. This results in lipid peroxidation, leading to edema and necrosis within the brain. (2)

Carcinogenicity (IARC Classification)

No indication of carcinogenicity to humans (not listed by IARC).

Minimum Risk Level

Not Available

Symptoms

Early symptoms of acute carbon monoxide poisoning are nonspecific and include headaches, nausea, and fatigue. Symptoms may progress to tachycardia and hypertension. The central nervous system is one of the organ systems most sensitive to poisoning and symptoms displayed include dizziness, ataxia, confusion, convulsions, unconsciousness, respiratory arrest, and even death. (2)

Treatment

Carbon monoxide poisoning is first treated by immediate removal from the source of exposure. High-flow or 100% oxygen should then be administered by a nonrebreather reservoir oxygen mask. Oxygen hastens the dissociation of carbon monoxide from hemoglobin, improving tissue oxygenation by reducing carbon monoxides biological half-life. Hyperbaric oxygen may also be used, as it increases carboxyhemoglobin dissociation to a greater extent than normal oxygen. (2)

Toxicity Values

Not Available

Health Effects

Health Effect	Relationship	Direction	Reference
hypertension	associated_with	positive	PMC12518403
cancer	associated_with	Not Available	PMC8830992 , PMC9784116
dizziness	associated_with	Not Available	PMC11739406
low birth weight	associated_with	Not Available	PMC12648132
stroke	associated_with	increase	PMC10946040
headache	associated_with	Not Available	PMC7093087
necrosis	associated_with	Not Available	PMC8877725
COVID-19	associated_with	increase	PMC11507386
nausea	associated_with	Not Available	PMC7093087
vascular disease	associated_with	increase	PMC10946040
vitiligo	associated_with	Not Available	PMC12800077

Exposure Sources

Source ID	Source	Sector	Reference
10	Insecticides	Agriculture & land management	Not Available
233	Brushes	Personal care & cosmetics	Not Available
411	Unclassified diagnostic agents	Healthcare, pharmaceuticals & veterinary products	Not Available
495	Ceilings	Building & Construction	Not Available
496	Fencing	Building & Construction	Not Available
497	Floors	Building & Construction	Not Available
498	Ladders	Building & Construction	Not Available
499	Roofs	Building & Construction	Not Available
503	Tents Or Canopies	Building & Construction	Not Available
504	Adjustable Resistors	Electrical & Electronic Equipment	Not Available
505	Amplifiers	Electrical & Electronic Equipment	Not Available
506	Antennas	Electrical & Electronic Equipment	Not Available
507	Auxiliary Devices	Electrical & Electronic Equipment	Not Available
508	Coils	Electrical & Electronic Equipment	Not Available
510	Communication Cables Or Conductors	Electrical & Electronic Equipment	Not Available
511	Conductors Or Conductive Bodies Characterised By The Conductive Materials	Electrical & Electronic Equipment	Not Available
514	Discharge Lamps	Electrical & Electronic Equipment	Not Available
515	Discharge Tubes With Liquid Pool Cathodes	Electrical & Electronic Equipment	Not Available
516	Electric Hearing Aids	Electrical & Electronic Equipment	Not Available
517	Electric Switches	Electrical & Electronic Equipment	Not Available
518	Electrically Stimulated Smoking Devices	Electrical & Electronic Equipment	Not Available
519	Electrodes	Electrical & Electronic Equipment	Not Available
520	Emergency Protective Devices	Electrical & Electronic Equipment	Not Available
521	Fixed Capacitors And Their Manufacture	Electrical & Electronic Equipment	Not Available
523	Gas Filled Discharge Tubes With Solid Cathode	Electrical & Electronic Equipment	Not Available
524	Hybrid Capacitors	Electrical & Electronic Equipment	Not Available
525	Line Transmission Systems	Electrical & Electronic Equipment	Not Available
526	Loudspeakers	Electrical & Electronic Equipment	Not Available
527	Magnets	Electrical & Electronic Equipment	Not Available
528	Microphones	Electrical & Electronic Equipment	Not Available
529	Power Cables	Electrical & Electronic Equipment	Not Available
530	Radio Transmission Systems	Electrical & Electronic Equipment	Not Available
531	Relays	Electrical & Electronic Equipment	Not Available
533	Sparking Plugs	Electrical & Electronic Equipment	Not Available
535	Superconducting Magnets And Superconducting Coils	Electrical & Electronic Equipment	Not Available
536	Superconductive Or Hyperconductive Conductors Cables Or Transmission Lines	Electrical & Electronic Equipment	Not Available
537	Television Systems	Electrical & Electronic Equipment	Not Available
538	Thin Magnetic Films	Electrical & Electronic Equipment	Not Available
539	Video Games	Electrical & Electronic Equipment	Not Available
540	X Ray Tubes	Electrical & Electronic Equipment	Not Available
542	Brew Kettles	Food, food processing & cookware	Not Available
544	Fermentation Processes For Beer	Food, food processing & cookware	Not Available
545	Food Preservation	Food, food processing & cookware	Not Available
547	Preparation Of Malt	Food, food processing & cookware	Not Available
548	Preparation Of Vinegar	Food, food processing & cookware	Not Available
549	Preparation Of Wine Or Sparkling Wine	Food, food processing & cookware	Not Available
550	Preparation Of Wort	Food, food processing & cookware	Not Available
551	Processing Fish	Food, food processing & cookware	Not Available
552	Processing Meats	Food, food processing & cookware	Not Available
554	Ash Trays	Household cleaning & consumer products	Not Available
555	Bleaching Agents	Household cleaning & consumer products	Not Available
556	Cigar Cigarettes	Household cleaning & consumer products	Not Available
559	Non Electric Simulated Smoking Devices	Household cleaning & consumer products	Not Available
560	Other Smoking Requisites	Household cleaning & consumer products	Not Available
561	Perfumes Within Detergents And Soaps	Household cleaning & consumer products	Not Available
562	Pipe Accessories	Household cleaning & consumer products	Not Available
563	Soap Detergents	Household cleaning & consumer products	Not Available
564	Soap Dispensers	Household cleaning & consumer products	Not Available
566	Tobacco Pipes	Household cleaning & consumer products	Not Available
568	Tobacco Product Moisture Control	Household cleaning & consumer products	Not Available
569	Tobacco Smoke Filters	Household cleaning & consumer products	Not Available
577	Watch Chains	Household items	Not Available
578	Making Cigars	Industrial manufacturing & chemical processing	Not Available
579	Manufacture Of Iron Or Steel	Industrial manufacturing & chemical processing	Not Available
580	Manufacture Preparation Of Tobacco Products	Industrial manufacturing & chemical processing	Not Available
581	Paper Making Machines	Industrial manufacturing & chemical processing	Not Available
583	Anchoring Equipment	Marine, shipping & aquaculture	Not Available
584	Buoys	Marine, shipping & aquaculture	Not Available
588	Inflatable Life Saving Equipment	Marine, shipping & aquaculture	Not Available
589	Life Buoys	Marine, shipping & aquaculture	Not Available
591	Lifeboats	Marine, shipping & aquaculture	Not Available
592	Marine Propulsion Or Steering	Marine, shipping & aquaculture	Not Available
593	Nautical Instruments	Marine, shipping & aquaculture	Not Available
594	Ship Hulls	Marine, shipping & aquaculture	Not Available
596	Acaricides	Agriculture & land management	Not Available
598	Fertiliser Distributors	Agriculture & land management	Not Available
600	Herbicides And Algicides	Agriculture & land management	Not Available
604	Pest Attractants	Agriculture & land management	Not Available
606	Plant Growth Regulators	Agriculture & land management	Not Available
609	Aftershave	Personal care & cosmetics	Not Available
610	Aftersun Products	Personal care & cosmetics	Not Available
611	Anti Perspirants Or Body Deoderants	Personal care & cosmetics	Not Available
612	Body Washing Or Cleaning Implements	Personal care & cosmetics	Not Available
614	Essential Oils Or Perfumes	Personal care & cosmetics	Not Available
615	Eye Makeup Products	Personal care & cosmetics	Not Available
617	Lip Care Products	Personal care & cosmetics	Not Available
618	Lip Makeup Products	Personal care & cosmetics	Not Available
630	Toys	Recreation & sports surfaces	Not Available
632	Apparel	Textiles, leather & furnishings	Not Available
634	Buckles	Textiles, leather & furnishings	Not Available
635	Buttons	Textiles, leather & furnishings	Not Available
638	Decorating Textiles	Textiles, leather & furnishings	Not Available
640	Embroidering And Tufting	Textiles, leather & furnishings	Not Available
642	Footwear	Textiles, leather & furnishings	Not Available
643	Headwear	Textiles, leather & furnishings	Not Available
647	Multicolour Dyeing	Textiles, leather & furnishings	Not Available
649	Pins Clothes	Textiles, leather & furnishings	Not Available
650	Purses Luggage Hand Bags	Textiles, leather & furnishings	Not Available
652	Ropes	Textiles, leather & furnishings	Not Available
653	Sewing	Textiles, leather & furnishings	Not Available
655	Slide Fasteners	Textiles, leather & furnishings	Not Available
657	Surface Finishing Of Leather	Textiles, leather & furnishings	Not Available
659	Transfer Printing	Textiles, leather & furnishings	Not Available
661	Umbrellas	Textiles, leather & furnishings	Not Available
662	Yarns Or Threads	Textiles, leather & furnishings	Not Available

Pathways

10 pathways

Porphyrin Metabolism

Acute Intermittent Porphyria

Porphyria Variegata (PV)

Congenital Erythropoietic Porphyria (CEP) or Gunther Disease

Hereditary Coproporphyria (HCP)

Acute Intermittent Porphyria

Porphyria Variegata (PV)

Congenital Erythropoietic Porphyria (CEP) or Gunther Disease

Hereditary Coproporphyria (HCP)

Carbon monoxide Drug Metabolism Action Pathway

Targets

Structure	Protein	UniProt ID	Organism	Relationship	Details
Click to view 3D structure	Cytochrome c oxidase subunit 1	P00395	Humans	Known	Carbon monoxide can bind to cytochrome c oxidase, though with a lesser affinity than oxygen. This interferes with aerobic metabolism and efficient ATP synthesis. As a result, cells switch to anaerobic metabolism, causing anoxia, lactic acidosis, and eventual cell death. (L961)
Click to view 3D structure	Cytochrome c oxidase subunit 2	P00403	Humans	Known	Carbon monoxide can bind to cytochrome c oxidase, though with a lesser affinity than oxygen. This interferes with aerobic metabolism and efficient ATP synthesis. As a result, cells switch to anaerobic metabolism, causing anoxia, lactic acidosis, and eventual cell death. (L961)
Click to view 3D structure	Cytochrome c oxidase subunit 3	P00414	Humans	Known	Carbon monoxide can bind to cytochrome c oxidase, though with a lesser affinity than oxygen. This interferes with aerobic metabolism and efficient ATP synthesis. As a result, cells switch to anaerobic metabolism, causing anoxia, lactic acidosis, and eventual cell death. (L961)
Click to view 3D structure	Cytochrome c oxidase subunit 4 isoform 1, mitochondrial	P13073	Humans	Known	Carbon monoxide can bind to cytochrome c oxidase, though with a lesser affinity than oxygen. This interferes with aerobic metabolism and efficient ATP synthesis. As a result, cells switch to anaerobic metabolism, causing anoxia, lactic acidosis, and eventual cell death. (L961)
Click to view 3D structure	Cytochrome c oxidase subunit 5A, mitochondrial	P20674	Humans	Known	Carbon monoxide can bind to cytochrome c oxidase, though with a lesser affinity than oxygen. This interferes with aerobic metabolism and efficient ATP synthesis. As a result, cells switch to anaerobic metabolism, causing anoxia, lactic acidosis, and eventual cell death. (L961)
Click to view 3D structure	Cytochrome c oxidase subunit 5B, mitochondrial	P10606	Humans	Known	Carbon monoxide can bind to cytochrome c oxidase, though with a lesser affinity than oxygen. This interferes with aerobic metabolism and efficient ATP synthesis. As a result, cells switch to anaerobic metabolism, causing anoxia, lactic acidosis, and eventual cell death. (L961)
Click to view 3D structure	Cytochrome c oxidase subunit 6A2, mitochondrial	Q02221	Humans	Known	Carbon monoxide can bind to cytochrome c oxidase, though with a lesser affinity than oxygen. This interferes with aerobic metabolism and efficient ATP synthesis. As a result, cells switch to anaerobic metabolism, causing anoxia, lactic acidosis, and eventual cell death. (L961)
Click to view 3D structure	Cytochrome c oxidase subunit 6B1	P14854	Humans	Known	Carbon monoxide can bind to cytochrome c oxidase, though with a lesser affinity than oxygen. This interferes with aerobic metabolism and efficient ATP synthesis. As a result, cells switch to anaerobic metabolism, causing anoxia, lactic acidosis, and eventual cell death. (L961)
Click to view 3D structure	Cytochrome c oxidase subunit 6C	P09669	Humans	Known	Carbon monoxide can bind to cytochrome c oxidase, though with a lesser affinity than oxygen. This interferes with aerobic metabolism and efficient ATP synthesis. As a result, cells switch to anaerobic metabolism, causing anoxia, lactic acidosis, and eventual cell death. (L961)
Click to view 3D structure	Cytochrome c oxidase subunit 7A1, mitochondrial	P24310	Humans	Known	Carbon monoxide can bind to cytochrome c oxidase, though with a lesser affinity than oxygen. This interferes with aerobic metabolism and efficient ATP synthesis. As a result, cells switch to anaerobic metabolism, causing anoxia, lactic acidosis, and eventual cell death. (L961)
Click to view 3D structure	Cytochrome c oxidase subunit 7B, mitochondrial	P24311	Humans	Known	Carbon monoxide can bind to cytochrome c oxidase, though with a lesser affinity than oxygen. This interferes with aerobic metabolism and efficient ATP synthesis. As a result, cells switch to anaerobic metabolism, causing anoxia, lactic acidosis, and eventual cell death. (L961)
Click to view 3D structure	Cytochrome c oxidase subunit 7C, mitochondrial	P15954	Humans	Known	Carbon monoxide can bind to cytochrome c oxidase, though with a lesser affinity than oxygen. This interferes with aerobic metabolism and efficient ATP synthesis. As a result, cells switch to anaerobic metabolism, causing anoxia, lactic acidosis, and eventual cell death. (L961)
Click to view 3D structure	Cytochrome c oxidase subunit 8A, mitochondrial	P10176	Humans	Known	Carbon monoxide can bind to cytochrome c oxidase, though with a lesser affinity than oxygen. This interferes with aerobic metabolism and efficient ATP synthesis. As a result, cells switch to anaerobic metabolism, causing anoxia, lactic acidosis, and eventual cell death. (L961)
Click to view 3D structure	Hemoglobin subunit alpha	P69905	Humans	Known	Carbon monoxide combines with hemoglobin to form carboxyhemoglobin (HbCO) in the blood. As carbon moxoxide has a higher affinity for hemoglobin than oxygen, this prevents the transport, delivery, and utilization of oxygen, causing anoxemia. (L961)
Click to view 3D structure	Hemoglobin subunit beta	P68871	Humans	Known	Carbon monoxide combines with hemoglobin to form carboxyhemoglobin (HbCO) in the blood. As carbon moxoxide has a higher affinity for hemoglobin than oxygen, this prevents the transport, delivery, and utilization of oxygen, causing anoxemia. (L961)
Click to view 3D structure	Myoglobin	P02144	Humans	Known	Carbon monoxide binds to myoglobin, impairing its ability to utilize oxygen. (L961)
Click to view 3D structure	Myoglobin	P02144	Humans	Known	Not Available

Concentrations

Not Available

External Links

DrugBank ID

DB11588

HMDB ID

HMDB0001361

FooDB ID

FDB022578

Phenol Explorer ID

Not Available

KNApSAcK ID

Not Available

BiGG ID

1749973

BioCyc ID

CARBON-MONOXIDE

METLIN ID

Not Available

PDB ID

Not Available

Wikipedia Link

Chemspider ID

ChEBI ID

PubChem Compound ID

Kegg Compound ID

YMDB ID

ECMDB ID

References

Synthesis Reference

Ivanova, Svetlana; Pitchon, Veronique; Petit, Corinne. Application of the direct exchange method in the preparation of gold catalysts supported on different oxide materials. Journal of Molecular Catalysis A: Chemical (2006), 256(1-2), 278-283.

MSDS

Not Available

General References

1. Ivanova, Svetlana; Pitchon, Veronique; Petit, Corinne. Application of the direct exchange method in the preparation of gold catalysts supported on different oxide materials. Journal of Molecular Catalysis A: Chemical (2006), 256(1-2), 278-283.

2. https://www.ncbi.nlm.nih.gov/pubmed/?term=10085152

3. https://www.ncbi.nlm.nih.gov/pubmed/?term=10679539

4. https://www.ncbi.nlm.nih.gov/pubmed/?term=11572959

5. https://www.ncbi.nlm.nih.gov/pubmed/?term=14527438

6. https://www.ncbi.nlm.nih.gov/pubmed/?term=14563665

7. https://www.ncbi.nlm.nih.gov/pubmed/?term=15127883

8. https://www.ncbi.nlm.nih.gov/pubmed/?term=15598489

9. https://www.ncbi.nlm.nih.gov/pubmed/?term=16371440