1,2-Ethanedithiol

94.2

94.20

505946

208-752-3

92T634FLAR

60481

DTXSID9052187

Liquid

29309070

2

1.21 (est)

Clear slightly colored Liquid

1.123 g/cm³ @ Temp: 23.5 °C

-41.2 °C

146 °C @ Press: 760 Torr

122 °F

1.517

H2O: insoluble

Store at 0-5°C

4.8 mm Hg ( 20 °C)

>1 (vs air)

LD50 orally in Rabbit: 120 mg/kg LD50 dermal Rabbit 197 mg/kg

Henry's Law constant = 1.2X10-4 atm-cu m/mol at 25 °C (est)

pKa = 8.96 at 30 °C

Liquid Molar Volume = 0.084191 cu m/kmol; IG Heat of Formation = -9.70X10+6 J/kmol|Hydroxyl radical reaction rate constant = 8.3X10-11 cu cm/molec-sec at 25 °C (est)

III

3

UN 3071 6.1/PG 2

3

10-23/24/25-23/25-21-36-23-21/22-36/37/38-20/21/22

36/37/39-45-26-16-36/37-36-7/9

KI3325000

T,Xn,F

Stable. Flammable. Incompatible with oxidizing agents, bases, reducing agents, alkali metals.

P260-P280-P284-P301 + P310-P302 + P350-P305 + P351 + P338

H226-H301-H310 + H330-H319

SRP: The most favorable course of action is to use an alternative chemical product with less inherent propensity for occupational exposure or environmental contamination. 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 soil or water; effects on animal, aquatic, and plant life; and conformance with environmental and public health regulations.

|Danger|H226 (94.81%): Flammable liquid and vapor [Warning Flammable liquids]|P210, P233, P240, P241, P242, P243, P260, P262, P264, P270, P271, P280, P284, P301+P310, P301+P312, P302+P350, P302+P352, P303+P361+P353, P304+P340, P305+P351+P338, P310, P312, P320, P321, P322, P330, P337+P313, P361, P363, P370+P378, P403+P233, P403+P235, P405, and P501|Aggregated GHS information provided by 308 companies from 11 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

LD50 Rat oral 120 mg/kg|LD50 Mouse ip 50 mg/kg|LD50 Mouse iv 56.2 mg/kg|LD50 Rabbit dermal 197 mg/kg

/AQUATIC SPECIES/ Static aquatic assays were conducted for 24 hr on three species of fish. No mortality or change in equilibrium resulted from 5 ppm in Northern squawfish, and 10 ppm caused the death of Coho salmon, steelhead trout, and Northern squawfish in 2 to 14 hr (high alkalinity and hardness). In different water conditions (low alkalinity and hardness), mortality was observed in Northern squawfish at 10 ppm in 7 to 19 hr.

1,2-Ethanedithiol's production and use as a metal complexing agent(1) may result in its release to the environment through various waste streams(SRC).

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 44(SRC), determined from a structure estimation method(2), indicates that 1,2-ethanedithiol is expected to have very high mobility in soil(SRC). Volatilization of 1,2-ethanedithiol from moist soil surfaces is expected to be an important fate process(SRC) given an estimated Henry's Law constant of 1.2X10-4 atm-cu m/mole(SRC), using a fragment constant estimation method(3). 1,2-Ethanedithiol is expected to volatilize from dry soil surfaces(SRC) based upon an extrapolated vapor pressure of 5.61 mm Hg(4). Biodegradation data were not available(SRC, 2005).|AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 44(SRC), determined from a structure estimation method(2), indicates that 1,2-ethanedithiol is not expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is expected(3) based upon an estimated Henry's Law constant of 1.2X10-4 atm-cu m/mole(SRC), developed using a fragment constant estimation method(4). Using this Henry's Law constant and an estimation method(3), volatilization half-lives for a model river and model lake are 3 days and 17 days, respectively(SRC). According to a classification scheme(5), an estimated BCF of 2(SRC), from an estimated log Kow of 1.2(6) and a regression-derived equation(7), suggests the potential for bioconcentration in aquatic organisms is low(SRC). Biodegradation data were not available(SRC, 2005).|ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), 1,2-ethanedithiol, which has an extrapolated vapor pressure of 5.61 mm Hg at 25 °C(2), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase 1,2-ethanedithiol 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 hours(SRC), calculated from its rate constant of 8.3X10-11 cu cm/molecule-sec at 25 °C(SRC) that was derived using a structure estimation method(3). 1,2-Ethanedithiol does not contain chromophores that absorb at wavelengths >290 nm and therefore is not expected to be susceptible to direct photolysis by sunlight(SRC).

The rate constant for the vapor-phase reaction of 1,2-ethanedithiol with photochemically-produced hydroxyl radicals has been estimated as 8.3X10-11 cu cm/molecule-sec at 25 °C(SRC) using a structure estimation method(1). This corresponds to an atmospheric half-life of about 5 hours at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(1). 1,2-Ethanedithiol is not expected to undergo hydrolysis in the environment due to the lack of hydrolyzable functional groups(2). 1,2-Ethanedithiol does not contain chromophores that absorb at wavelengths >290 nm and therefore is not expected to be susceptible to direct photolysis by sunlight(SRC).

An estimated BCF of 2 was calculated for 1,2-ethanedithiol(SRC), using an estimated log Kow of 1.21(1) and a regression-derived equation(2). According to a classification scheme(3), 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 1,2-ethanedithiol can be estimated to be 44(SRC). According to a classification scheme(2), this estimated Koc value suggests that 1,2-ethanedithiol is expected to have very high mobility in soil.

The Henry's Law constant for 1,2-ethanedithiol is estimated as 1.2X10-4 atm-cu m/mole(SRC) using a fragment constant estimation method(1). This Henry's Law constant indicates that 1,2-ethanedithiol is expected to volatilize from water surfaces(2). Based on this Henry's Law constant, the volatilization half-life from a model river (1 m deep, flowing 1 m/sec, wind velocity of 3 m/sec)(2) is estimated as 2 days(SRC). The volatilization half-life from a model lake (1 m deep, flowing 0.05 m/sec, wind velocity of 0.5 m/sec)(2) is estimated as 17 days(SRC). 1,2-Ethanedithiol is expected to volatilize from dry soil surfaces(SRC) based upon a vapor pressure of 5.61 mm Hg(3).

Occupational exposure to 1,2-ethanedithiol may occur through inhalation and dermal contact with this compound at workplaces where 1,2-ethanedithiol is produced or used. (SRC)

Urinary metabolites could result from methylation, S-oxidation of one S atom to yield a polar sulfonate, and the formation of mixed disulfides of low relative molecular mass such as cysteine, an endogenous thiol. /Dithiols/|Simple aliphatic and aromatic thiols undergo S-methylation in mammals to produce the corresponding methyl thioether or sulfide. Methylation is catalysed by thiopurine methyltransferase in the cytoplasm and thiol methyltransferase in microsomes, and both reactions require S-adenosyl-l-methionine as a methyl group donor. Thiopurine methyltransferase is present in human liver, kidney, and erythrocytes; preferential substrates for this enzyme include aromatic and heterocyclic thiols. S-Methylation of aliphatic thiols is catalysed by microsomal thiol methyltransferase, and the resulting methyl thioether (sulfide) metabolite would undergo S-oxidation to give the methyl sulfoxide and methyl sulfone analogues as urinary products. Thiols may react with glutathione and other endogenous thiol substances to form mixed disulfides. Both microsomal and cytoplasmic thioltransferasess have been reported to catalyse the formation of mixed disulfides. The resulting mixed disulfides can undergo reduction back to thiols, oxidative desulfuration, or oxidation to a sulfonic acid via the intermediate thiosulfinate and sulfinic acids. The principal form in the circulation would probably be a mixed disulfide formed with albumin. /Simple thiols/

/SRP:/ Basic treatment: Establish a patent airway. Suction if necessary. Watch for signs of respiratory insufficiency and assist ventilations if necessary. Administer oxygen by nonrebreather mask at 10 to 15 L/min. Monitor for pulmonary edema and treat if necessary ... . Anticipate seizures and treat if necessary ... . For eye contamination, flush eyes immediately with water. Irrigate each eye continuously with normal saline during transport ... . Do not use emetics. For ingestion, rinse mouth and administer 5 m1/kg up to 200 ml of water for dilution if the patient can swallow, has a strong gag reflex, and does not drool ... . Administer activated charcoal ... . Cover skin burns with dry sterile dressings after decontamination ... . /Sulfur and related compounds/|/SRP:/ Advanced treatment: Consider orotracheal or nasotracheal intubation for airway control in the patient who is unconscious. Early intubation at the first sign of upper airway obstruction may be necessary. Monitor cardiac rhythm and treat arrhythmias if necessary ... . Start an IV with D5W /SRP: "To keep open", minimal flow rate/. Use lactated Ringer's if signs of hypovolemia are present. Watch for signs of fluid overload. Consider drug therapy for pulmonary edema ... . Treat seizures with diazepam ... . For hypotension with signs of hypovolemia, administer fluid cautiously. Consider vasopressors for hypotension with a normal fluid volume. Watch for signs of fluid overload ... . Use proparacaine hydrochloride to assist eye irrigation ... . /Sulfur and related compounds/

/SIGNS AND SYMPTOMS/ Vapors of ethanedithiol may cause severe headache and nausea.|/CASE REPORTS/ ... A 22-year-old female chemistry student who developed widespread erythema multiforme-like lesions after local contact with 1,2-ethanedithiol. Many target lesions were observed bilaterally on her hands, forearms, arms, and on her forehead. One such lesion was histologically compatible with erythema multiforme. The patient had a positive patch test to 1,2-ethanedithiol, whereas none of 30 healthy subjects showed a positive reaction. However, eight of the 30 controls (26.7%) developed irritant reactions to 1,2-ethanedithiol.

1,2-ethanedithiol

1,2-Ethanedithiol: ACTIVE|Thiols can be prepared by a variety of methods. The most-utilized of these synthetic methods for tertiary and secondary thiols is acid-catalyzed synthesis; for normal and secondary thiols, the most-utilized methods are free-radical-initiated, alcohol substitution, or halide substitution; for mercaptoalcohols, the most-utilized method is oxirane addition; and for mercaptoacids and mercaptonitriles, the most-utilized methods are Michael-type additions. /Thiols/

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