| Description |
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. |
| 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. |
| Chemical Properties |
Ethylene oxide is the simplest cyclic ether. It is a colourless gas or liquid and has a sweet, etheric odour. Etylene oxide is a flammable and very reactive and explosive chemical substance. On decomposition, vapours of pure ethylene oxide mix with air or inert gases and become highly explosive. Industrial use of ethylene oxide is extensive, 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 fungicide and insecticide, in the sterilisation of surgical instruments/ equipments and heat-sensitive materials in the hospital, in the sterilisation/fumigation of some imported foods, in the fumigation of books and archival materials in museums, and in the fumigation of furs, textiles, and furniture. |
| Uses |
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. |
| Definition |
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). |
| 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. |
| 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 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 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 and SO2 can react violently in pyridine solution with pressurization if ETHYLENE OXIDE is in excess (Nolan, 1983, Case History 51). |
| Hazard |
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. |
| 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 |
| Agricultural Uses |
Fungicide and fumigant: Ethylene oxide is used as a fumigant for spices, seasonings, and foodstuffs and as an agricultural fungicide. When used directly in the gaseous form or in nonexplosive gaseous mixtures with nitrogen or carbon dioxide, ethylene oxide can act as a disinfectant, fumigant, sterilizing agent, and insecticide. It is a man-made chemical used as an intermediate in organic synthesis for ethylene glycol, polyglycols, glycol ethers, esters, ethanolamines, acrylonitrile, plastics, and surface-active agents. It is also used as a fumigant for textiles and for sterilization, especially for surgical instruments. It is used in drug synthesis and as a pesticide intermediate. Not approved for use in EU countries. Actively registered in the U.S. |
| Trade name |
AMPROLENE®; ANPROLENE®; ANPROLINE®; BIODAC®; MERPOL®; OXYFUME®; OXYFUME 12®; T-GAS®; STERILIZING GAS ETHYLENE OXIDE 100%® |
| 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 |
| 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. |
| Purification Methods |
Dry oxirane with CaSO4, then distil it from crushed NaOH. It has also been purified by passage, as a gas, through towers containing solid NaOH. [Beilstein 17/1 V 3.] |
| References |
https://en.wikipedia.org/wiki/Ethylene_oxide
https://www.cancer.gov/about-cancer/causes-prevention/risk/substances/ethylene-oxide |
