Record Information
Version2.0
Creation Date2014-10-03 17:11:19 UTC
Update Date2014-12-24 20:27:01 UTC
Accession NumberT3D4972
Identification
Common NameChlorine gas
ClassSmall Molecule
DescriptionUnder standard conditions, chlorine exists as a diatomic molecule. Chlorine is a highly toxic, pale yellow-green gas that has a specific strong smell similar to the smell of bleach. In nature, chlorine is most abundant as a chloride ion. In industry, elemental chlorine is usually produced by the electrolysis of sodium chloride dissolved in water. This method, the chloralkali process industrialized in 1892, now provides essentially all industrial chlorine gas. Along with chlorine, the method yields hydrogen gas and sodium hydroxide (with sodium hydroxide actually being the most crucial of the three industrial products produced by the process. Principal applications of chlorine are in the production of a wide range of industrial and consumer products. For example, it is used in making plastics, solvents for dry cleaning and metal degreasing, textiles, agrochemicals and pharmaceuticals, insecticides, dyestuffs, household cleaning products, etc. Chlorine is added both to pesticides and pharmaceuticals to make the molecules more resistant to enzymatic degradation by bacteria, insects, and mammals, but this property also has the effect of prolonging the residence time of these compounds when they enter the environment. In this respect chlorinated organics have some resemblance to fluorinated organics. Chlorine is used to prepare sodium and calcium hypochlorites. It is used as a disinfectant in water treatment, especially to make drinking water and in large public swimming pools . Chlorine was used extensively to bleach wood pulp, but this use has decreased significantly due to environmental concerns.
Compound Type
  • Disinfectant
  • Halogen
  • Industrial Precursor/Intermediate
  • Industrial/Workplace Toxin
  • Inorganic Compound
  • Lachrymator
  • Natural Compound
  • Non-Metal
  • Pollutant
  • Vapour
Chemical Structure
Thumb
Synonyms
Synonym
Chlorine
Cl
Cl2
Diatomic chlorine
Dichlorine
Molecular chlorine
Chemical FormulaCl2
Average Molecular Mass70.906 g/mol
Monoisotopic Mass69.938 g/mol
CAS Registry Number7782-50-5
IUPAC Namedichlorane
Traditional Namechlorine
SMILESClCl
InChI IdentifierInChI=1S/Cl2/c1-2
InChI KeyInChIKey=KZBUYRJDOAKODT-UHFFFAOYSA-N
Chemical Taxonomy
Description belongs to the class of inorganic compounds known as homogeneous halogens. These are inorganic non-metallic compounds in which the largest atom is a nobel gas.
KingdomInorganic compounds
Super ClassHomogeneous non-metal compounds
ClassHomogeneous halogens
Sub ClassNot Available
Direct ParentHomogeneous halogens
Alternative Parents
Substituents
  • Homogeneous halogen
  • Inorganic chloride salt
  • Inorganic salt
Molecular FrameworkNot Available
External Descriptors
Biological Properties
StatusDetected and Not Quantified
OriginExogenous
Cellular Locations
  • Cytoplasm
  • Extracellular
  • Microsome
  • Plasma Membrane
Biofluid LocationsNot Available
Tissue Locations
  • All Tissues
Pathways
NameSMPDB LinkKEGG Link
ApoptosisNot Availablemap04210
Oxidative phosphorylationNot Availablemap00190
Metabolic PathwaysNot AvailableNot Available
Dna replicationNot Availablemap03030
ApplicationsNot Available
Biological RolesNot Available
Chemical RolesNot Available
Physical Properties
StateGas
AppearanceGreen/yellow gas
Experimental Properties
PropertyValue
Melting Point-101 oC
Boiling Point-34 oC
Solubility6.3 mg/mL at 25 C [AMOORE,JE & HAUTALA,E (1983)]
LogPNot Available
Predicted Properties
PropertyValueSource
logP1.08ChemAxon
Physiological Charge0ChemAxon
Hydrogen Acceptor Count0ChemAxon
Hydrogen Donor Count0ChemAxon
Polar Surface Area0 ŲChemAxon
Rotatable Bond Count0ChemAxon
Refractivity12.27 m³·mol⁻¹ChemAxon
Polarizability4.55 ųChemAxon
Number of Rings0ChemAxon
Bioavailability1ChemAxon
Rule of FiveYesChemAxon
Ghose FilterYesChemAxon
Veber's RuleYesChemAxon
MDDR-like RuleYesChemAxon
Spectra
Spectra
Spectrum TypeDescriptionSplash KeyDeposition DateView
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Positivesplash10-00di-9000000000-6e822575d1c944b1c9e82016-08-03View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Positivesplash10-00di-9000000000-6e822575d1c944b1c9e82016-08-03View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Positivesplash10-00di-9000000000-6e822575d1c944b1c9e82016-08-03View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Negativesplash10-014i-9000000000-dbca39d50c160aa387212016-08-03View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Negativesplash10-014i-9000000000-dbca39d50c160aa387212016-08-03View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Negativesplash10-014i-9000000000-dbca39d50c160aa387212016-08-03View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 10V, Positivesplash10-00di-9000000000-10127e6b10c0dfc2fcc52021-10-21View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 20V, Positivesplash10-00di-9000000000-10127e6b10c0dfc2fcc52021-10-21View Spectrum
Predicted LC-MS/MSPredicted LC-MS/MS Spectrum - 40V, Positivesplash10-00di-9000000000-10127e6b10c0dfc2fcc52021-10-21View Spectrum
MSMass Spectrum (Electron Ionization)splash10-00dr-9000000000-3cbc095f1caa401edb8c2015-03-01View Spectrum
Toxicity Profile
Route of ExposureInhalation (2) ; dermal (2)
Mechanism of ToxicityChlorine is a strong oxidizer that hydrolyzes in water forming hydrochloric and hypochlorous acids. In this form, it can penetrate the cell and form N-chloro-derivatives that can damage cellular integrity. Chlorine reacts with water in the epithelial lining of the upper respiratory airways. The mechanism of toxicity of aqueous chlorine or a hypochlorous acid/sodium hypochlorite is basically the same as that for chlorine gas. However, hypochlorous acid is a stronger oxidant than chlorine gas as reflected by its higher redox potential. Damage to the upper gastrointestinal tract, as may occur following ingestion of sodium hypochlorite bleach, is likely the result of oxidation reactions of hypochlorous acid with a range of biological molecules.
MetabolismHypochlorous acid reacts with proteins, amino acids, and unsaturated lipids to form chlorinated compounds, whereas the reaction with carbohydrates yields oxidation products. Metabolisation of chlorine results in the production of N-chloramines, tentatively identified as N-chloroalanine, N-chloroglycine, and N-chlorophenylalanine. (1)
Toxicity ValuesCoughing and vomiting may occur at 30 ppm and lung damage at 60 ppm. About 1000 ppm can be fatal after a few deep breaths of the gas.
Lethal DoseA few deep breaths of chlorine gas at 1000 ppm is usually fatal.
Carcinogenicity (IARC Classification)No indication of carcinogenicity (not listed by IARC). (3)
Uses/SourcesChlorine is used in making plastics, solvents for dry cleaning and metal degreasing, textiles, agrochemicals and pharmaceuticals, insecticides, dyestuffs, household cleaning products. Chlorine is also used to prepare sodium and calcium hypochlorites. It is used as a disinfectant in water treatment, especially to make drinking water and in large public swimming pools. Chlorine was used extensively to bleach wood pulp, but this use has decreased significantly due to environmental concerns. Exposure usually results from inhaling contaminated air, ingesting chlorine bleach or directly contacting the skin with aqueous chlorine. (1)
Minimum Risk LevelAcute Inhalation: 0.07 ppm (Chlorine gas) (1) Intermediate Inhalation: 0.02 ppm (Chlorine gas) (1) Chronic Inhalation: 0.00005 ppm (Chlorine gas) (1)
Health EffectsThe principal targets of exposure to chlorine gas are the respiratory airways and the eyes. Exposure to chlorine gas can lead to mild irritation of the nose, eye irritation and headache and throat irritation. Pulmonary edema and hypoxia can follow and further increase capillary permeability. Further complications can lead to pneumonia and even death. The principal targets of exposure to aqueous chlorine are the upper gastrointestinal tract and the skin. Ingestion of chlorine can lead to esophageal and gastric mucosal erosions, perforations at the gastroesophageal junction, and extensive necrosis of adjacent soft tissue. (1)
SymptomsIf inhaled, chlorine can trigger cough, substernal pain, respiratory distress, shortness of breath, and wheezing. Symptoms may be delayed. Nausea and vomiting are reflex in origin, and headache and loss of consciousness are probably due to the hypoxia caused by pulmonary edema. Dermal contact can lead to redness, pain, and redness of the exposed surface. Eye contact can lead to watering of the eyes. (1, 2)
TreatmentIn case of inhalation, move patient to fresh air. Monitor for respiratory distress. If cough or difficulty breathing develops, evaluate for respiratory tract irritation, bronchitis, or pneumonitis. Administer oxygen and assist ventilation as required. Treat bronchospasm with an inhaled beta2 agonist and oral or parenteral corticosteroids. Examine mucous membranes, eyes and skin to be certain that corrosive effects have not occurred. In case of acute lung injury, maintain ventilation and oxygenation and evaluate with frequent arterial blood gas or pulse oximetry monitoring. In case of eye exposure, irrigate exposed eyes with copious amounts of room temperature water for at least 15 minutes. In case of dermal exposure, remove contaminated clothing and wash exposed area thoroughly with soap and water.
Normal Concentrations
Not Available
Abnormal Concentrations
Not Available
DrugBank IDNot Available
HMDB IDNot Available
PubChem Compound ID24526
ChEMBL IDNot Available
ChemSpider ID22933
KEGG IDNot Available
UniProt IDNot Available
OMIM ID
ChEBI ID29310
BioCyc IDNot Available
CTD IDNot Available
Stitch IDNot Available
PDB IDNot Available
ACToR IDNot Available
Wikipedia LinkNot Available
References
Synthesis ReferenceNot Available
MSDSNot Available
General References
  1. ATSDR - Agency for Toxic Substances and Disease Registry (2007). Toxicological profile for chlorine. U.S. Public Health Service in collaboration with U.S. Environmental Protection Agency (EPA). [Link]
  2. International Programme on Chemical Safety (IPCS) INCHEM (2008). Poison Information Monograph for Chlorine. [Link]
  3. International Agency for Research on Cancer (2014). IARC Monographs on the Evaluation of Carcinogenic Risks to Humans. [Link]
Gene Regulation
Up-Regulated GenesNot Available
Down-Regulated GenesNot Available