1,1′-Oxybis[2-[(2-chloroethyl)thio]ethane]

263.24

263.25

58818

DTXSID7074799

Sulfur mustards are colorless when pure, but are typically yellow to brown oily liquids. /Sulfur mustards/|Sulfur mustards can be clear to yellow or brown when in liquid or solid form. /Sulfur mustards/|Powder

2930909090

59.83000

2.94700

This is a chemical weapon related to sulfur mustard (mustard gas) and is expected to react in a similar fashion. See the chemical datasheet for sulfur mustard for more information.

1.209g/cm3

45 °C

120 °C @ Press: 1 x 10^-3 Torr

179.9ºC

1.523

Sulfur mustards, including Agent T (O-Mustard), do not dissolve much in water, but dissolve easily in oils, fats, and other solvents. /Sulfur mustards/

3X10-6 mm Hg at 25 °C

Garlic-like odor

When heated to decomposition it emits very toxic fumes of SOx and Cl-.|No rapid reaction with air. No rapid reaction with water, but is water reactive.|O-Mustard (Agent T) has a much lower volatility than mustard gas and a lower vapor pressure than sulfur mustard which makes it inefficient as a respiratory agent by itself. It can be mixed with sulfur mustard to make Agent HT.|Hydroxyl radical reaction rate constant = 7.5X10-11 cu cm/molec-sec at 25 °C (est)

No rapid reaction with air. No rapid reaction with water.

Ethers

Water-Reactive

SRP: Recycle any unused portion of the material for its approved use or return it to the manufacturer or supplier. Ultimate disposal of the chemical must consider: the material's impact on air quality; potential migration in air, soil or water; effects on animal, aquatic and plant life; and conformance with environmental and public health regulations. If it is possible or reasonable use an alternative chemical product with less inherent propensity for occupational harm/injury/toxicity or environmental contamination.

Skin/ocular protection: Personal protective equipment (PPE) and butyl rubber chemical-protective gloves are recommended at all times when these chemicals are suspected to be involved. /Sulfur mustards/|Respiratory protection: Pressure-demand, self-contained breathing apparatus (SCBA) is recommended in response situations that involve exposure to any amount of sulfur mustard. /Sulfur mustards/|MOPP4 /All protection worn/ whenever liquid or vapor is present. /Mustard-T Mixture (HT)/

People whose skin or clothing is contaminated with sulfur mustard can contaminate rescuers by direct contact or through off-gasing vapor. /Sulfur mustard/

In August 1988, chemical weapons were reported used against Kurdish populations in the mountainous region of northern Iraq close to the borders of Turkey and Iran(1). In November of that year, soil samples (and other samples) were collected from a hillside site of an impacted bomb(1). Analysis of the soil samples identified degradation products of sulfur mustard and O-mustard(1).

O-Mustard decontamination derivatives were detected in decontamination waste from chemical weapons (CW) agents stored in containers on Johnston Atoll (US territory located in the Pacific Ocean) since 1971(1).

IDENTIFICATION AND USE: O-Mustard is colorless when pure but is typically a yellow to brown oily substance with a slight garlic or mustard odor. This is a warfare and terrorism agent. HUMAN STUDIES: High doses of sulfur mustards can cause hyperexcitability, convulsions, and insomnia. The eye is the most sensitive tissue to sulfur mustard effects. Sulfur mustard vapor or liquid may cause intense conjunctival and scleral pain, swelling, lacrimation, blepharospasm, and photophobia; however, these effects do not appear for an hour or more. Miosis due to cholinergic effects may occur. High concentrations of vapor or liquid can cause corneal edema, perforation, blindness, and later scarring. Direct skin exposure to sulfur mustards causes erythema and blistering. Generally, a pruritic rash will develop within 4 to 8 hours followed by blistering 2 to 18 hours later. Contact with the vapor may result in first and second degree burns, while contact with the liquid typically produces second and third degree chemical burns. An area of burn covering 25% or more of the body surface area may be fatal. Ingestion may cause chemical burns of the GI tract and cholinergic stimulation. Nausea and vomiting may occur following ingestion or inhalation. Early nausea and vomiting is usually transient and not severe. Nausea, vomiting, and diarrhea occurring several days after exposure indicates damage to the GI tract and thus is a poor prognostic sign. Dose-dependent inflammatory reactions in the upper and lower airway begin to develop several hours after exposure and progress over several days. Burning nasal pain, epistaxis, sinus pain, laryngitis, loss of taste and smell, cough, wheezing, and dyspnea may occur. Necrosis of respiratory epithelium can cause pseudomembrane formation and local airway obstruction. Death usually occurs between 5 and 10 days due to pulmonary insufficiency complicated by infection due to immune system compromise. Systemic absorption of sulfur mustard may induce bone marrow suppression and an increased risk for fatal complicating infections, hemorrhage, and anemia. Years after apparent healing of severe eye lesions, relapsing keratitis or keratopathy may develop. Prolonged or repeated acute exposure to sulfur mustards may cause cutaneous sensitization and chronic respiratory disease. ANIMAL STUDIES: There are no data available.

The lethal dose is about 100 mg/kg or 1 to 1.5 teaspoons of liquid. /Sulfur mustard/

LC50 Mice inhalation 1650 mg/cu m/ 10 min

O-Mustard's limited production for research may result in its release to the environment through various waste streams; its illegal use as a chemical warfare agent(1,2) will result in its direct release to the environment(SRC). Destruction of US stockpiles of chemical agents, including sulfur mustards, was mandated by the Chemical Weapons Convention to take place before April 2007(2).

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 1180(SRC), determined from a structure estimation method(2), indicates that O-Mustard is expected to have low mobility in soil(SRC). Volatilization of O-Mustard from moist soil surfaces is not expected to be an important fate process(SRC) given an estimated Henry's Law constant of 3.8X10-8 atm-cu m/mole(SRC), using a fragment constant estimation method(2). The Sulfur Mustards, including Agent T (O-Mustard), do not dissolve much in water(3), but the small quantity that dissolves is reactive(4). The hydrolysis half-life of dissolved O-Mustard was determined to be 2.8 minutes at 25 °C(5). O-Mustard is not expected to volatilize from dry soil surfaces(SRC) based upon a vapor pressure of 3X10-6 mm Hg at 25 °C(6). Biodegradation data in soil were not available(SRC, 2017).|AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 1180(SRC), determined from a structure estimation method(2), indicates that O-Mustard is expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is not expected(3) based upon an estimated Henry's Law constant of 3.8X10-8 atm-cu m/mole(SRC), developed using a fragment constant estimation method(2). The Sulfur Mustards, including Agent T (O-Mustard), do not dissolve much in water(4), but the small quantity that dissolves is reactive(5). The hydrolysis half-life of dissolved O-Mustard was determined to be 2.8 minutes at 25 °C(6). According to a classification scheme(7), an estimated BCF of 28(SRC), from an estimated log Kow of 2.71(2) and a regression-derived equation(2), suggests the potential for bioconcentration in aquatic organisms is low(SRC). Biodegradation data in water were not available(SRC, 2017).|ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), O-Mustard, which has a vapor pressure of 3X10-6 mm Hg at 25 °C(2), will exist in both the vapor and particulate phases in the ambient atmosphere. Vapor-phase O-Mustard is degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals(SRC); the half-life for this reaction in air is estimated to be 5.2 hours(SRC), calculated from its rate constant of 7.5X10-11 cu cm/molecule-sec at 25 °C(SRC) that was derived using a structure estimation method(3). Particulate-phase O-Mustard may be removed from the air by wet and dry deposition(SRC).

The rate constant for the vapor-phase reaction of O-Mustard with photochemically-produced hydroxyl radicals has been estimated as 7.5X10-11 cu cm/molecule-sec at 25 °C(SRC) using a structure estimation method(1). This corresponds to an atmospheric half-life of about 5.2 hours at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(1). The apparent hydrolysis half-life of O-Mustard at 25 °C was determined to be 2.8 minutes in an aqueous solution containing 5% ethanol at pH of 5-8(1).

An estimated BCF of 28 was calculated in fish for O-Mustard(SRC), using an estimated log Kow of 2.71(1) and a regression-derived equation(1). According to a classification scheme(2), this BCF suggests the potential for bioconcentration in aquatic organisms is low(SRC).

Using a structure estimation method based on molecular connectivity indices(1), the Koc of O-Mustard can be estimated to be 1180(SRC). According to a classification scheme(2), this estimated Koc value suggests that O-Mustard is expected to have low mobility in soil.

The Henry's Law constant for O-Mustard is estimated as 3.8X10-8 atm-cu m/mole(SRC) using a fragment constant estimation method(1). This Henry's Law constant indicates that O-Mustard is expected to be essentially nonvolatile from water surfaces(2). In addition, any O-Mustard that dissolves into water will be reactive with the water(3). O-Mustard's Henry's Law constant indicates that volatilization from moist soil surfaces is not expected to occur(SRC). O-Mustard is not expected to volatilize from dry soil surfaces(SRC) based upon a vapor pressure of 3X10-6 mm Hg at 25 °C(4).

Occupational exposure to O-Mustard may occur through inhalation and dermal contact with this compound at workplaces where O-Mustard is produced or used. (SRC)

The lethal dose is about 100 mg/kg or 1 to 1.5 teaspoons of liquid. /Sulfur mustard/

/SRP:/ 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. /Blister Agents (Vesicants)/|/SRP:/ Basic treatment: Establish a patent airway (oropharyngeal or nasopharyngeal airway, if needed). Suction if necessary. Aggressive airway control may be needed. Watch for signs of respiratory insufficiency and assist ventilations it necessary. 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 ... . Anticipate seizures and treat if necessary ... . For eye contamination, flush eyes immediately with water. Irrigate each eye continuously with 0.9% saline (NS) during transport ... . /Blister Agents (Vesicants)/|/SRP:/ Advanced treatment: Consider orotracheal or nasotracheal intubation for airway control in the patient who is unconscious 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. 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 ... . Treat seizures with diazepam (Valium) or lorazepam (Ativan) ... . Use proparacaine hydrochloride to assist eye irrigation ... . /Blister Agents (Vesicants)/|Symptoms may not develop for 24 hours. Patients who are seen at least 24 hours after exposure and whose symptoms indicate mild exposure may be sent home after treatment and once their names, addresses, and telephone numbers have been recorded. They should be advised to rest and to seek medical care promptly if additional symptoms develop... /Sulfur mustards/|Because signs and symptoms of exposure do not occur for several hours postexposure, patients should be observed for at least 6 hours or sent home with instructions to return immediately if symptoms develop. Patients whose clinical effects and time of onset indicate moderate or severe exposure and patients who have ingested sulfur mustard should be transported to a medical facility for evaluation. /Sulfur mustard/

/SIGNS AND SYMPTOMS/ Eyes are very susceptible to low concentrations; incapacitating effects by skin absorption require higher concentrations than does eye injury. /Mustard-T Mixture (HT)/|/SIGNS AND SYMPTOMS/ It is somewhat more vesicant than Levinstein mustard (H) on bare skin; however, it is less vesicant through wet or dry clothing and is somewhat less effective than H on the eyes. /Mustard-T Mixture (HT)/|/SIGNS AND SYMPTOMS/ Death usually occurs between the 5 and 10 day due to pulmonary insufficiency complicated by infection due to immune system compromise. /Sulfur mustards/|/SIGNS AND SYMPTOMS/ The eye is the most sensitive tissue to sulfur mustard effects. Sulfur mustard vapor or liquid may cause intense conjunctival and scleral pain, swelling, lacrimation, blepharospasm, and photophobia; however, these effects do not appear for an hour or more. Miosis due to cholinergic effects may occur. High concentrations of vapor or liquid can cause corneal edema, perforation, blindness, and later scarring. /Sulfur mustards/|For more Human Toxicity Excerpts (Complete) data for O-Mustard (16 total), please visit the HSDB record page.

Agent HT is generally a mixture of 60% HD /distilled mustard or bis(2-chloroethyl)sulfide/ and 40% bis(2-chloroethylthioethyl)ether (T), although this ratio may vary.

O-Mustard is listed in the CWC /Chemical Weapons Convention/ Annex on Chemicals under Schedule 1.|/The Chemical Weapons Convention (CWC) is an international treaty which bans the development, production, stockpiling, and transfer or use of chemical weapons. The Convention mandates the destruction and prohibition of chemical weapons and related facilities and provides for restrictions on international trade in toxic chemicals and precursors./ The Convention's monitoring and verification measures involve submission of declarations regarding ... /Schedule 1, 2, and 3 chemicals/ and inspections by the Organization for the Prohibition of Chemical Weapons of the facilities where these chemicals are produced. ... Schedule 1 lists chemicals considered to pose a high risk to the object and purpose of the Convention by virtue of their high potential for use in activities prohibited by the CWC. These chemicals have little or no use for peaceful purposes in commercial or industrial trade. ... Schedule 1 also lists precursor chemicals that may be used in the final single technological stage of production of any of the toxic chemicals listed in the schedule.|Sulfur mustards H/HD and HT are manufactured compounds. They are colorless when pure, but are typically yellow to brown oily liquids with a slight garlic or mustard odor. Agent H contains about 20-30% impurities. The nearly pure substance is called HD. HT is a mixture of 60% HD and 40% of another substance called agent T. They do not dissolve much in water, but dissolve easily in oils, fats, and other solvents. They are stable at ambient temperatures. Sulfur mustards were introduced as chemical warfare agents during World War I. More than a dozen countries have sulfur mustard agents in their chemical arsenals. Destruction of U.S. stockpiles of chemical agents, including sulfur mustards, was mandated by the Chemical Weapons Convention to take place before April 2007.|In the period following World War I and during World War II, a wide variety of sulfur analogues of mustard were investigated and many potent vesicants were discovered. Each had two 2-chloroethyl groups attached to a sulfur atom. Examples of such compounds are 1,2-bis(2-chloroethylthio)ethane (Chemical Agent Symbol Q), ... and bis(2-chloroethylthioethyl) ether (T), ... . It is noteworthy that each 2-chloroethyl group is associated with a separate sulfur atom, not with the same one as for mustard. Both Q and T are more vesicant than mustard, but neither is as volatile. For that reason, neither is as effective by the vapor route.

In an effort to detect and identify longer chain sulfur vesicant hydrolysis products, capillary column gas chromatography (GC)/mass spectrometry (MS) and GC/MS were used under electron impact (EI) and ammonia chemical impact (ACI) conditions. Using this approach it was possible to characterize the partial and fully hydrolyzed products of 2-chloro-ethyl-(2-chloroethoxy)ethyl-sulfide, bis(2-chloroethylthio)ethane (sesquimustard) and bis((2-chloroethylthio)ethyl)-ether before and after trimethylsilyl derivatization. As part of the third United Nations Conference on Disarmament Technical Group on Instrumentation Round Robin Analytical Exercise, spiked concrete samples which would be typical of those taken during inspection of a military facility were prepared and distributed to evaluate the analytical procedures at several laboratories. HQ and HT, two munitions grade mustard formulations which contained mainly mustard and sesquimustard, and mustard and bis((2-dichloroethylthio)ethyl)-ether were hydrolyzed to characterize the principal hydrolysis products of these munitions samples. In general, the data obtained from EI lacked significant molecular ion information but those obtained during ACI contained useful molecular ion information.|Capillary column gas chromatography ammonia and deuterated ammonia chemical ionization (CI) mass spectrometry (MS) was shown to be a highly specific technique for detecting and identifying three long chain sulfur vesicants: 2-chloroethyl(2-chloroethoxy)ethyl-sulfide, sesquimustard and bis((2-chloroethylthio)ethyl)ether. Each of the vesicants exhibited significant pseudo molecular ions and structurally significant CI fragmentation ions during capillary column gas chromatography ammonia CI-MS analysis. Deuterated ammonia CI data were acquired for all three compounds to confirm the identity of two unusual CI fragmentation ions. This approach was demonstrated during the analysis of contaminated painted panels as a part of a round robin verification exercise. CI data obtained during this exercise complemented the electron impact (EI) data obtained for sesquimustard and bis(2-chloroethylthio)ethyl)ether and the specificity of the technique enabled the confirmation of 2-chloroethyl(2-chloroethoxy)ethyl-sulfide, a compound masked by the presence of hydrocarbons during EI-MS analysis of the painted panel extracts. The CI data provided were sufficient for the detection and confirmation of three long chain sulfur vesicants controlled under the proposed United Nations Chemical Weapons Convention.