Sesquimustard

219.199

219.20

5Y1NV229PO

30025

DTXSID7074793

Solid

2930909090

50.60000

2.93040

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.

1.229g/cm3

54 °C

328.7ºC at 760mmHg

144.9ºC

1.535

Although sulfur mustards have limited solubility in water at neutral pH, the small quantity that dissolves is reactive. /Sulfur mustards/

3.5X10-6 mm Hg at 25 °C

LC50 inhalation in dog: 90mg/m3/2M

Garlic-like odor

Henry's Law constant = 4.7X10-9 atm-cu m/mole at 25 °C (est)

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.|Sesquimustard (Agent Q) 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.|Hydroxyl radical reaction rate constant = 2.7X10-11 cu cm/molec-sec at 25 °C (est)

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

Halogenated Organic Compounds

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.|A simple and economical chemical neutralization method is developed against highly toxic chemical warfare agents viz. sulfur mustard (SM), sesquimustard, and their homologous/analogous. The method involves treatment of chemical warfare agents with sodium in inert solvents. This destruction method of sulfur mustards release innocuous products via desulfurization reactions. The products were characterized by GC-MS technique. The method is suitable in particular, for bulk destruction of heel of mustard stockpiles.

SOIL: 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 sesquimustard(1).

Sesquimustard 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). Sesquimustard occurs as an impurity in sulfur mustard used as a chemical warfare agent(2).

IDENTIFICATION AND USE: Sesquimustard (Q) is a vesicant/blister agent more potent than distilled mustard (HD). It is combined with HD to form agent HQ. It could also be formed in small amounts during storage of HD in ton containers. HUMAN STUDIES: Vesicants, also referred to as "blister agents," were the most commonly used chemical warfare agents during World War I. The most likely routes of exposure are inhalation, dermal contact, and ocular contact. Vesicants are highly reactive chemicals that combine with proteins, DNA, and other cellular components to result in cellular changes immediately after exposure. Clinical effects may be delayed for 2 to 24 hours. Following exposure, the most commonly encountered clinical effects include dermal (skin erythema and blistering), respiratory (pharyngitis, cough, dyspnea), ocular (conjunctivitis and burns), and gastrointestinal (nausea and vomiting). The amount and route of exposure to the vesicant, the type of vesicant, and the premorbid condition of the person exposed will contribute to the time of onset and the severity of illness. For example, ingestion of a vesicant leads to gastrointestinal symptoms more prominent than those that would result from inhalation exposure to the same dose and type of vesicant. ANIMAL STUDIES: Acute inhalation toxicity studies with sesquimustard have been made in mice, rats, guinea pigs, hamsters, pigeons, and dogs. Following exposure, animals show loss of body weight, coughing, dyspnea, ataxia, and diarrhea prior to death. Deaths occurred over a 14-day observation period with a primary peak between the third and sixth day. Tissue damage in most animals was limited to the upper respiratory tract and digestive tract.

LC50 Mice inhalation 6 mg/cu m/10 min|LC50 Rat inhalation 11 mg/cu m/10 min|LC50 Dog inhalation 90 mg/cu m/2 min|LC50 Cat inhalation 900 mg/cu m/ 10 min|For more Non-Human Toxicity Values (Complete) data for Sesquimustard (8 total), please visit the HSDB record page.

Sesquimustard's production may result in its release to the environment through various waste streams; its use as a chemical warfare agent(1) 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 1450(SRC), determined from a structure estimation method(2), indicates that sesquimustard is expected to have low mobility in soil(SRC). Volatilization of sesquimustard from moist soil surfaces is not expected to be an important fate process(SRC) given an estimated Henry's Law constant of 4.7X10-9 atm-cu m/mole(SRC), developed using a fragment constant estimation method(2). The Sulfur Mustards do not dissolve much in water(3), but the small quantity that dissolves is reactive(4). The hydrolysis half-life of dissolved sesquimustard was determined to be 1.7 minutes at 25 °C(5). Sesquimustard is not expected to volatilize from dry soil surfaces(SRC) based upon a vapor pressure of 3.5X10-6 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 1450(SRC), determined from a structure estimation method(2), indicates that sesquimustard 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 4.7X10-9 atm-cu m/mole(SRC), developed using a fragment constant estimation method(2). The Sulfur Mustards do not dissolve much in water(4), but the small quantity that dissolves is reactive(5). The hydrolysis half-life of dissolved sesquimustard was determined to be 1.7 minutes at 25 °C(6). According to a classification scheme(7), an estimated BCF of 43(SRC), from an estimated log Kow of 2.99(2) and a regression-derived equation(2), suggests the potential for bioconcentration in aquatic organisms is moderate(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), sesquimustard, which has a vapor pressure of 3.5X10-6 mm Hg at 25 °C(2), will exist in both the vapor and particulate phases in the ambient atmosphere. Vapor-phase sesquimustard 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 14 hours(SRC), calculated from its rate constant of 2.7X10-11 cu cm/molecule-sec at 25 °C(SRC) that was derived using a structure estimation method(3). Particulate-phase sesquimustard may be removed from the air by wet and dry deposition(SRC).

The rate constant for the vapor-phase reaction of sesquimustard with photochemically-produced hydroxyl radicals has been estimated as 2.7X10-11 cu cm/molecule-sec at 25 °C(SRC) using a structure estimation method(1). This corresponds to an atmospheric half-life of about 14 hours at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(1). The apparent hydrolysis half-life of sesquimustard at 28 °C was determined to be 8.1 minutes in an aqueous solution containing 32% dioxane(1); the hydrolysis half-life extrapolated to pure water at 25 °C is 1.7 minutes(2).

An estimated BCF of 43 was calculated in fish for sesquimustard(SRC), using an estimated log Kow of 2.99(1) and a regression-derived equation(1). According to a classification scheme(2), this BCF suggests the potential for bioconcentration in aquatic organisms is moderate(SRC).

Using a structure estimation method based on molecular connectivity indices(1), the Koc of sesquimustard can be estimated to be 1450(SRC). According to a classification scheme(2), this estimated Koc value suggests that sesquimustard is expected to have low mobility in soil(SRC).

The Henry's Law constant for sesquimustard is estimated as 4.7X10-9 atm-cu m/mole(SRC) using a fragment constant estimation method(1). This Henry's Law constant indicates that sesquimustard is expected to be essentially nonvolatile from water surfaces(2). In addition, any sesquimustard that dissolves into water will be reactive with the water(3). Sesquimustard's Henry's Law constant indicates that volatilization from moist soil surfaces is not expected to occur(SRC). Sesquimustard is not expected to volatilize from dry soil surfaces(SRC) based upon a vapor pressure of 3.5X10-6 mm Hg at 25 °C(4).

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

Sesqui- and oxy-mustards pose a significant threat to military forces and civilians because they are potent vesicants. We have developed an isotope-dilution high-performance liquid chromatography-atmospheric pressure chemical ionization-tandem mass spectrometry method utilizing negative ion multiple reaction monitoring for the analysis of sesqui-mustard metabolites bis(2-hydroxyethylthio)alkanes (n = 1-5) and oxy-mustard metabolite bis(2-hydroxyethylthioethyl)ether in human urine. Relative standard deviations were < 10% and the reportable limits of detection were 1 ng/mL in 0.5 mL of urine. We applied this method to 100 samples collected from individuals with no known exposure to sesqui- or oxy-mustards, and no urines showed detectable levels of any of the analytes, suggesting that these metabolites may be used for monitoring exposure to sesqui- and oxy-mustards.

/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)/

/SIGNS AND SYMPTOMS/ Vesicants, also referred to as "blister agents," were the most commonly used chemical warfare agents during World War I. The most likely routes of exposure are inhalation, dermal contact, and ocular contact. Vesicants are highly reactive chemicals that combine with proteins, DNA, and other cellular components to result in cellular changes immediately after exposure. Depending on the vesicant, clinical effects may occur immediately (as with phosgene oxime or lewisite) or may be delayed for 2 to 24 hours (as with mustards). Following exposure, the most commonly encountered clinical effects include dermal (skin erythema and blistering), respiratory (pharyngitis, cough, dyspnea), ocular (conjunctivitis and burns), and gastrointestinal (nausea and vomiting). The amount and route of exposure to the vesicant, the type of vesicant, and the premorbid condition of the person exposed will contribute to the time of onset and the severity of illness. For example, ingestion of a vesicant leads to gastrointestinal symptoms more prominent than those that would result from inhalation exposure to the same dose and type of vesicant. /Vesicants/|/SIGNS AND SYMPTOMS/ Respiratory signs and symptoms: chest tightness, clear rhinorrhea, cough Dyspnea (shortness of breath), hemoptysis, nasal irritation/pain, sore throat, tachypnea. /Vesicants/|/SIGNS AND SYMPTOMS/ Dermal signs and symptoms: blisters (within 1 hour with phosgene oxime, delayed for 2 to 12 hours with lewisite, delayed for 2 to 24 hours with mustards); erythema (immediate with lewisite and phosgene oxime, may be delayed for 2 to 24 hours with mustards); immediate blanching (phosgene oxime); itching; necrosis and eschar (over a period of 7 to 10 days). /Vesicants/|/SIGNS AND SYMPTOMS/ Ocular signs and symptoms: blindness, blurred vision, corneal ulceration, conjunctivitis, eyelid edema, eye pain/burning, lacrimation, photophobia. /Vesicants/|For more Human Toxicity Excerpts (Complete) data for Sesquimustard (10 total), please visit the HSDB record page.

Sesquimustard 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.|...HD /sulfur mustard/ stored for approximately 40 years in ton containers was 89.2% pure. The main impurity (4.7%) was 1,2-bis-(2-chloroethylthioethane), also know as compound Q or sesquimustard.|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.

Sesqui- and oxy-mustards pose a significant threat to military forces and civilians because they are potent vesicants. We have developed an isotope-dilution high-performance liquid chromatography-atmospheric pressure chemical ionization-tandem mass spectrometry method utilizing negative ion multiple reaction monitoring for the analysis of sesqui-mustard metabolites bis(2-hydroxyethylthio)alkanes (n = 1-5) and oxy-mustard metabolite bis(2-hydroxyethylthioethyl)ether in human urine. Relative standard deviations were < 10% and the reportable limits of detection were 1 ng/mL in 0.5 mL of urine. We applied this method to 100 samples collected from individuals with no known exposure to sesqui- or oxy-mustards, and no urines showed detectable levels of any of the analytes, suggesting that these metabolites may be used for monitoring exposure to sesqui- and oxy-mustards.