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Supplier Related Products Identification Chemical Properties Hazard Information Safety Data Raw materials And Preparation Products Material Safety Data Sheet(MSDS) Questions and Answers (Q&A) Spectrum Detail Well-known Reagent Company Product Information

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Molecular Formula
MDL Number
Molecular Weight
MOL File

Chemical Properties

colourless gas
Ethylene oxide is a colorless, compressed, liquefied gas or liquid (below 11℃). Sweet odor; the odor threshold is 50 ppm.
Melting point 
−111 °C(lit.)

−111 °C(lit.)

Boiling point 
10.7 °C(lit.)

10.7 °C(lit.)

0.882 g/mL at 25 °C(lit.)

refractive index 
n20/D 1.3597(lit.)

storage temp. 
Contact allergens
Ethylene oxide is a very strong irritant widely used in the chemical industry, and as a sterilizer of medical supplies, pharmaceutical products, and food. It can produce immediate (urticaria, asthma, anaphylaxis) or delayed reactions (irritant rather than allergic contact dermatitis). For example, residues in masks or dressings can produce irritant contact dermatitis.In delayed contact allergy, it seems that cross-reaction can be observed to epichlorhydrin or epoxypropane
CAS DataBase Reference
75-21-8(CAS DataBase Reference)

Hazard Information

Chemical Properties
colourless gas
Chemical Properties
Ethylene oxide is the simplest cyclic ether. It is a colorless gas or liquid and has a sweet, etheric odor. Ethylene oxide is a flammable, very reactive and explosive chemical substance. On decomposition, vapors of pure ethylene oxide mix with air or inert gases and become highly explosive. Ethylene oxide, is used in large scale as an intermediate in the production of monoethylene glycol, diethylene glycol, triethylene glycol, poly(ethylene) glycols, ethylene glycol ethers, ethanolamine, ethoxylation products of fatty alcohols, fatty amines, alkyl phenols, cellulose, and poly(propylene glycol). It is also used as a fumigant for food and cosmetics, and in hospital sterilization of surgical equipment and heat sensitive materials.
Fumigant for foodstuffs and textiles; to sterilize surgical instruments; agricultural fungicide. In organic syntheses, especially in the production of ethylene glycol. Starting material for the manufacture of acrylonitrile and nonionic surfactants.
ChEBI: A saturated organic heteromonocyclic parent that is a three-membered heterocycle of two carbon atoms and one oxygen atom.
General Description
A clear colorless gas with an ethereal odor. Flash point below 0°F. May polymerize exothermically if heated or contaminated. If the polymerization takes place inside a container, the container may rupture violently. Vapors may burn inside a container. Vapors irritate the eyes, skin, and respiratory system. Prolonged skin contact may result in delayed burns. Less dense than water. Vapors heavier than air. Vapors very toxic. Under prolonged exposure to fire or heat the containers may rupture violently and rocket. Used to make other chemicals, as a fumigant and industrial sterilant (AAR, 1999).
Reactivity Profile
Colorless gas at room temperature (b.p. 11°C), confirmed carcinogen. Highly flammable, severe explosion hazard when exposed to flame. The autoignition temperature may be as low as 140° C in presence of rust. Rapid compression of the vapor with air causes explosion. ETHYLENE OXIDE(75-21-8) vapor may be initiated into explosive decomposition in absence of air [Hess, L. G., et al., Ind. Eng. Chem., 1950, 42, p. 1251]. Metal fittings containing magnesium, copper or silver should be avoided, since traces of acetylene in ETHYLENE OXIDE(75-21-8) may produce metal acetylides capable of detonating the vapor [MCA SD-38, 1971]. Violent polymerization occurs on contact with strong bases (alkali hydroxides, ammonia) or acids, amines, metallic potassium, oxides (aluminum oxide, iron oxide, rust), covalent halides (aluminum chloride, ferric chloride, tin(IV) chloride) [Gupta, A. K., J. Soc. Chem. Ind., 1949, 68, p. 179]. Violent reaction with m-nitroaniline, magnesium perchlorate, mercaptans, thiols, triethylamine [Bretherick, 5th ed., 1995, p. 316]. ETHYLENE OXIDE(75-21-8) and SO2 can react violently in pyridine solution with pressurization if ETHYLENE OXIDE(75-21-8) is in excess (Nolan, 1983, Case History 51).
Air & Water Reactions
Highly flammable. Flammable over a wide vapor-air concentration range. Must be diluted on the order of 24 to 1 with water to lose flammability. Soluble in water.
Irritant to eyes and skin. Confirmed carcinogen. Highly flammable, dangerous fire and explosion risk, flammable limits in air 3–100%.
Health Hazard
Ethylene oxide is toxic by inhalation. Symptoms of overexposure include headache, dizziness, lethargy, behavioral disturbances, weakness, cyanosis, loss of sensation in the extremities, reduction in the sense of smell and/or taste, progressing with increasing exposure to convulsions, seizure and coma. Ethylene oxide is also an irritant to the skin and the respiratory tract, and inhaling the vapors may cause the lungs to fi ll with fl uid several hours after exposure. Inhalation may cause dizziness or drowsiness. Liquid contact may cause frostbite, and an allergic skin reaction. After oral exposure (ingestion) to ethylene oxide, laboratory animals show adverse effects in the blood, damage to the liver, kidneys, reproductive effects, miscarriages/spontaneous abortion, and cancer
Health Hazard
ETHYLENE OXIDE can cause death. Lowest inhalation concentration causing toxic effects is 12500 ppm/10 seconds. It is a strong skin irritant. Neurological disorders and even death have been reported.
Potential Exposure
Ethylene oxide is a man-made chemical used in the production of glycols (ethylene glycol, polyglycols, glycol ethers, esters), nontonic surface-active agent; ethanolamines, acrylonitrile, plastics. It is also used as a fumigant for foodstuffs and textiles; an agricultural fungicide; and for sterilization, especially for surgical instruments. It is used in drug synthesis and as a pesticide intermediate
First aid
If ethylene oxide gets into the eyes, remove any contact lenses at once and irrigate immediately for at least 15 minutes, occasionally lifting upper and lower lids. Seek medical attention immediately. If this chemical contacts the skin, remove contaminated clothing and wash immediately with soap and water. Seek medical attention immediately. If this chemical has been inhaled, remove from exposure, begin rescue breathing (using universal precautions, including resuscitation mask) if breathing has stopped and CPR if heart action has stopped. Transfer promptly to a medical facility. When this chemical has been swallowed, get medical attention. Give large quantities of water and induce vomiting. Do not make an unconscious person vomit. If frostbite has occurred, seek medical attention immediately; do NOT rub the affected areas or flush them with water. In order to prevent further tissue damage, do NOT attempt to remove frozen clothing from frostbitten areas. If frostbite has NOT occurred, immediately and thoroughly wash contaminated skin with soap and water. Medical observation is recommended for 24 to 48 hours after breathing overexposure, as pulmonary edema may be delayed. As first aid for pulmonary edema, a doctor or authorized paramedic may consider administering a drug or other inhalation therapy.
Fire Hazard
Severe explosion hazard when exposed to heat or flame. Irritating vapors are generated when heated. Vapor is heavier than air and may travel considerable distance to a source of ignition and flash back. Vapor forms explosive mixtures with air over a wide range. Liquid is not detonable but the vapor may be readily initiated into explosive decomposition. Avoid metal fittings containing copper, silver, mercury or magnesium; ammonia, oxidizing agents; acids, organic bases; amines; certain salts; alcohols; mercaptans, ferric chloride; magnesium perchlorate; m-nitroaniline; trimethylamine, potassium, tin chlorides; alkanethiols; bromoethane; aluminum chloride; aluminum oxide; iron chlorides; and iron oxides. Avoid air, heat, acids and bases, metal or metal chloride catalysts. Hazardous polymerization may occur. Avoid acids; covalent halides such as chlorides of aluminum, iron (III), tin (IV); basic materials like alkali hydrides, ammonia, amines, and potassium; catalytically active solids such as aluminum or iron oxides or rust, chlorides of boron, aluminum, tin, and iron; some carbonates; and metals such as copper and copper alloys
UN1040 Ethylene oxide or Ethylene oxide with nitrogen up to a total pressure of 1 MPa (10 bar) at 50℃, Hazard Class: 2.3; Labels: 2.3-Poisonous gas, 2.1- Flammable gas, Inhalation Hazard Zone D. Cylinders must be transported in a secure upright position, in a wellventilated truck. Protect cylinder and labels from physical damage. The owner of the compressed gas cylinder is the only entity allowed by federal law (49CFR) to transport and refill them. It is a violation of transportation regulations to refill compressed gas cylinders without the express written permission of the owner
May form explosive mixture with air. Chemically unstable. Dangerously reactive; may rearrange chemically and/or polymerize violently with evolution of heat; when in contact with highly active catalytic surfaces, such as anhydrous chlorides of iron, tin and aluminum; pure oxides of iron and aluminum; and alkali metal hydroxides. Even small amounts of strong acids; alkalis, or oxidizers can cause a reaction. Avoid contact with copper. Protect container from physical damage, sun and heat. Attacks some plastics, rubber or coatings.
Waste Disposal
Return refillable compressed gas cylinders to supplier. Concentrated waste containing no peroxides-discharge liquid at a controlled rate near a pilot flame. Concentrated waste containing peroxides-perforation of a container of the waste from a safe distance followed by open burning

Safety Data

Hazard Codes 
Risk Statements 
R45:May cause cancer.
R12:Extremely Flammable.
R23:Toxic by inhalation.
R36/37/38:Irritating to eyes, respiratory system and skin .
R39/23/24/25:Toxic: danger of very serious irreversible effects through inhalation, in contact with skin and if swallowed .
R23/24/25:Toxic by inhalation, in contact with skin and if swallowed .
R11:Highly Flammable.
Safety Statements 
S53:Avoid exposure-obtain special instruction before use .
S45:In case of accident or if you feel unwell, seek medical advice immediately (show label where possible) .
S36/37:Wear suitable protective clothing and gloves .
S16:Keep away from sources of ignition-No smoking .
S24/25:Avoid contact with skin and eyes .
S23:Do not breathe gas/fumes/vapor/spray (appropriate wording to be specified by the manufacturer) .
UN 2037 2.3

WGK Germany 


HS Code 
Ethylene oxide is dangerously explosive under fi re condition; it is flammable over an extremely large range of concentrations in air and burns in the absence of oxygen.
Safety Profile
Confirmed human carcinogen with experimental carcinogenic, tumorigenic, neoplastigenic, and teratogenic data. Poison by ingestion, intraperitoneal, subcutaneous, and intravenous routes. Moderately toxic by inhalation. Human systemic effects by inhalation: convulsions, nausea, vomiting, olfactory and pulmonary changes. Experimental reproductive effects. Mutation data reported. A skin and eye irritant. An irritant to mucous membranes of respiratory tract. High concentrations can cause pulmonary edema. Highly flammable liquid or gas. Severe explosion hazard when exposed to flame. To fight fire, use alcohol foam, CO2, dry chemical. Violent polymerization occurs on contact with ammonia, alkali hydroxides, amines, metalllc potassium, acids, covalent halides (e.g., aluminum chloride, iron(Ⅲ) chloride, tin(rv> chloride, aluminum oxide, iron oxide, rust). Explosive reaction with glycerol at 200℃. Rapid compression of the vapor with air causes explosions. Incompatible with bases, alcohols, air, m-nitroanlline, trimethyl amine, copper, iron chlorides, iron oxides, magnesium perchlorate, mercaptans, potassium, tin chlorides, contaminants, alkane thols, bromoethane. When heated to decomposition it emits acrid smoke and irritating fumes.

Raw materials And Preparation Products

Material Safety Data Sheet(MSDS)

msds information

Questions and Answers (Q&A)

Ethylene oxide (C2H4O) is a kind of cyclic ether with important industrial applications. Although it is highly toxic and dangerous for household application and consumers to use, it can be used for the manufacture of many important industrial and commercialized products as well as some chemicals and intermediates. For example, it is very useful in the production of detergents, thickeners, solvents, plastics, and many kinds of organic chemicals such as ethylene glycol, ethanolamines, simple and complex glycols, polyglycol ethers, and other compounds. It is also a commonly sterilization methods used in the healthcare industry. In addition, it can be used as an accelerator of maturation of tobacco leaves and fungicide, as well as the main component of thermobaric weapons (fuel-air explosives). In industry, it is generally manufactured through direct oxidation of ethylene. In low doses, it can be used as a pesticide and a sterilizing agent owing to its effect of causing DNA damage. However, this property also make it a potential carcinogen.

Spectrum Detail

Well-known Reagent Company Product Information

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