Methyl thiocyanate

1.068 at 77 °F (EPA, 1998) - Denser than water; will sink

1.068 g/cu cm at 25 °C

1.068 @25 °C

VERY SLIGHTLY SOL IN WATER; MISCIBLE WITH ALC, ETHER

Soluble in carbon tetrachloride.

266 to 271 °F at 760 mmHg (EPA, 1998)

130-133 °C

-60 °F (EPA, 1998)

-51 °C

-51 °C

10 mmHg at 70.88 °F (EPA, 1998)

12.1 [mmHg]

12.1 mm Hg at 25 °C

INDEX OF REFRACTION: 1.4669 @ 25 °C/D

INDEX OF REFRACTION: 1.4697 @ 20 °C/D

Danger

H226 (98%): Flammable liquid and vapor [Warning Flammable liquids]

P210, P233, P240, P241, P242, P243, P260, P261, P262, P264, P264+P265, P270, P271, P280, P284, P301+P316, P302+P352, P303+P361+P353, P304+P340, P305+P351+P338, P316, P319, P320, P321, P330, P332+P317, P337+P317, P361+P364, P362+P364, P370+P378, P403+P233, P403+P235, P405, and P501 (click each P-code to see the statement)

Aggregated GHS information provided per 49 reports by companies from 7 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

Chemical: Thiocyanic acid, methyl ester

Methyl thiocyanate: Does not have an individual approval but may be used under an appropriate group standard

The New Jersey Worker and Community Right to Know Act requires public and private employers to provide information about hazardous substances at their workplaces. (N.J.S.A. 34:5A-1 et. seq.)

When heated to decomposition, it emits very toxic fumes of oxides of nitrogen and sulfur. (Non-Specific -- Thiocyanates) Incompatible with nitric acid. Violent reactions have occurred when mixed with chlorates, nitrates, nitric acid, organic peroxides, peroxides, potassium chlorate, and sodium chlorate. This material is volatile. (EPA, 1998)

Releases cyanide after absorption into the body; Onset of symptoms may be delayed; [HSDB] Causes somnolence and convulsions in lethal dose studies of animals; [RTECS] A fast acting poison; [CAMEO] An irritant and lachrymator; Toxic by ingestion, inhalation, or skin absorption; May cause burns after skin contact and lung edema after inhalation; [Aldrich MSDS]

METHYL THIOCYANATE is a moderately toxic liquid, flammable. Violent, possibly explosive oxidation reaction when mixed with chlorates, nitrates, nitric acid, organic or inorganic peroxides, perchlorates. On contact with mineral acids or acid fumes deadly toxic hydrogen cyanide gas is produced. When heated to decomposition or on contact with mineral acids it emits highly toxic fumes of nitriles, oxides of sulfur and nitrogen [Lewis, 3rd ed., 1993, p. 879, 1234].

Releases of CERCLA hazardous substances are subject to the release reporting requirement of CERCLA section 103, codified at 40 CFR part 302, in addition to the requirements of 40 CFR part 355. Methyl thiocyanate is an extremely hazardous substance (EHS) subject to reporting requirements when stored in amounts in excess of its threshold planning quantity (TPQ) of 10,000 lbs.

Flam. Liq. 3 (98%)

Flammable agents - 2nd degree, Reactive agents - 1st degree

Methyl thiocyanate

1

20000

Toxic chemical that can be released at a facility.

(Non-Specific -- Pesticide, Liquid, n.o.s.) Keep unnecessary people away; isolate hazard area and deny entry. Stay upwind; keep out of low areas. Ventilate closed spaces before entering them. Wear positive pressure breathing apparatus and special protective clothing. Remove and isolate contaminated clothing at the site. If water pollution occurs, notify appropriate authorities.

Avoid inhalation and skin contact. (Non-Specific -- Pesticide, Liquid, n.o.s.) Do not touch spilled material; stop leak if you can do so without risk. Use water spray to reduce vapors. For small spills, absorb with sand or other noncombustible absorbent material and place into containers for later disposal. For large spills, dike far ahead of spill for later disposal. (EPA, 1998)

SRP: At the time of review, criteria for land treatment or burial (sanitary landfill) disposal practices are subject to significant revision. Prior to implementing land disposal of waste residue (including waste sludge), consult with environmental regulatory agencies for guidance on acceptable disposal practices.

0.18 [mg/m3]

2.0 [mg/m3]

12 [mg/m3]

For emergency situations, wear a positive pressure, pressure-demand, full facepiece self-contained breathing apparatus (SCBA) or pressure- demand supplied air respirator with escape SCBA and a fully-encapsulating, chemical resistant suit. (EPA, 1998)

Antidotes to cyanide poisoning include hydroxocobalamin and sodium nitrite, which release the cyanide from the cytochrome system, and rhodanase, which is an enzyme occurring naturally in mammals that combines serum cyanide with thiosulfate, producing comparatively harmless thiocyanate. Oxygen therapy can also be administered. (L97)

Exposure to high levels of cyanide for a short time harms the brain and heart and can even cause coma, seizures, apnea, cardiac arrest and death. Chronic inhalation of cyanide causes breathing difficulties, chest pain, vomiting, blood changes, headaches, and enlargement of the thyroid gland. Skin contact with cyanide salts can irritate and produce sores. (L96, L97)

TERRESTRIAL FATE: Based on a recommended classification scheme(1), an estimated Koc value of 8.3(SRC), determined from a structure estimation method(2), indicates that methyl thiocyanate is expected to have very high mobility in soil(SRC). Volatilization of methyl thiocyanate from moist soil surfaces is expected (SRC) based upon an estimated Henry's Law constant of 4.4X10-5 atm-cu m/mole(SRC), using a fragment constant estimation method(3). The potential for volatilization of methyl thiocyanate from dry soil surfaces is expected to exist(SRC) based on a measured vapor pressure of 12 mm Hg(4). Based upon a group contribution method for predicting the probability and rate of aerobic biodegradation(5), methyl thiocyanate has been estimated to biodegrade fast with primary biodegradation occurring over a period of days to weeks(SRC).

AQUATIC FATE: Based on a recommended classification scheme(1), an estimated Koc value of 8.3(SRC), determined from a structure estimation method(2), indicates that methyl thiocyanate is not expected to adsorb to suspended solids and sediment in water(SRC). Methyl thiocyanate is expected to volatilize from water surfaces(3,SRC) based on an estimated Henry's Law constant of 4.4X10-5 atm-cu m/mole(SRC), developed using a fragment constant estimation method(4). Estimated volatilization half-lives for a model river and model lake are 20 hours and 8.6 days, respectively(3,SRC). According to a classification scheme(5), an estimated BCF value of 2.1(3,SRC), from an estimated log Kow(6,SRC), suggests that bioconcentration in aquatic organisms is low(SRC). Based upon a group contribution method for predicting the probability and rate of aerobic biodegradation(7), methyl thiocyanate has been estimated to be highly biodegraded with ultimate biodegradation occurring over a period of weeks(SRC).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), methyl thiocyanate, which has an measured vapor pressure of 12 mm Hg at 25 °C(2,SRC), is expected to exist solely as a vapor in the ambient atmosphere. Vapor-phase methyl thiocyanate 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 about 15 days(3,SRC).

Organic nitriles decompose into cyanide ions both in vivo and in vitro. Consequently the primary mechanism of toxicity for organic nitriles is their production of toxic cyanide ions or hydrogen cyanide. Cyanide is an inhibitor of cytochrome c oxidase in the fourth complex of the electron transport chain (found in the membrane of the mitochondria of eukaryotic cells). It complexes with the ferric iron atom in this enzyme. The binding of cyanide to this cytochrome prevents transport of electrons from cytochrome c oxidase to oxygen. As a result, the electron transport chain is disrupted and the cell can no longer aerobically produce ATP for energy. Tissues that mainly depend on aerobic respiration, such as the central nervous system and the heart, are particularly affected. Cyanide is also known produce some of its toxic effects by binding to catalase, glutathione peroxidase, methemoglobin, hydroxocobalamin, phosphatase, tyrosinase, ascorbic acid oxidase, xanthine oxidase, succinic dehydrogenase, and Cu/Zn superoxide dismutase. Cyanide binds to the ferric ion of methemoglobin to form inactive cyanmethemoglobin. (L97)

Using a structure estimation method based on molecular connectivity indices(1), the Koc for methyl thiocyanate can be estimated to be about 8.3(SRC). According to a recommended classification scheme(2), this estimated Koc value suggests that methyl thiocyanate is expected to have very high mobility in soil(SRC).

SYMPTOMATOLOGY (LARGELY INFERRED FROM ANIMAL TESTS): 1. INGESTION OF CONCN SOLN MAY LEAD TO VOMITING BECAUSE OF MUCOSAL IRRITATION. ... 5. MASSIVE SKIN CONTAMINATION WITH ORGANIC THIOCYANATE SOLN MAY PRODUCE SYSTEMIC POISONING...&...LOCAL IRRITATION & DERMATITIS. /ALIPHATIC THIOCYANATES/

SYMPTOMATOLOGY (LARGELY INFERRED FROM ANIMAL TESTS): 6. IN NONFATAL CASES EVIDENCE OF INJURIES TO THE LIVER & KIDNEYS MAY APPEAR. /ALIPHATIC THIOCYANATES/

...METHYL.../THIOCYANATE IS/ RAPIDLY ACTING /POISON/...OF HIGH POTENCY...

THE SIGNS AND SYMPTOMS OF KEROSENE POISONING ARE OFTEN DOMINANT AFTER EXPOSURES TO DILUTE SOLN OF THIOCYANATE INSECTICIDES. /ALIPHATIC THIOCYANATES/

Releases of CERCLA hazardous substances are subject to the release reporting requirement of CERCLA section 103, codified at 40 CFR part 302, in addition to the requirements of 40 CFR part 355. Methyl thiocyanate is an extremely hazardous substance (EHS) subject to reporting requirements when stored in amounts in excess of its threshold planning quantity (TPQ) of 10,000 lbs.

Methyl thiocyanate

1

20000

Toxic chemical that can be released at a facility.

ENZYMES IN THE LIVER AND PERHAPS OTHER ORGANS ARE KNOWN TO LIBERATE CYANIDE ION FROM METHYL...THIOCYANATE... GLUTATHIONE S-TRANSFERASE CATALYZES THE ATTACK OF REDUCED GLUTATHIONE @ THIOCYANATE SULFUR, RESULTING IN LIBERATION OF HYDROGEN CYANIDE, OXIDIZED GLUTATHIONE & THE MERCAPTAN MOIETY OF THE ORGANOTHIOCYANATE.

METHYL THIOCYANATE UP TO 5 MMOL REDUCED THE HYDROGEN ION SECRETION OF BULLFROG, RANA CATESBEIANA, GASTRIC MUCOSA WITHOUT EXHIBITING ANY APPRECIABLE INHIBITORY EFFECT ON MICROSOMAL ATPASE ACTIVITY. NO CONVERSION OF METHYL THIOCYANATE TO THIOCYANATE ION, A POTENT INHIBITOR OF GASTRIC ACID SECRETION, WAS DEMONSTRATED IN THE GASTRIC MUCOSA.

Organic nitriles are converted into cyanide ions through the action of cytochrome P450 enzymes in the liver. Cyanide is rapidly absorbed and distributed throughout the body. Cyanide is mainly metabolized into thiocyanate by either rhodanese or 3-mercaptopyruvate sulfur transferase. Cyanide metabolites are excreted in the urine. (L96)

Used as an agricultural insecticide, fumigant, pharmaceutical intermediate, and research chemical; [HSDB]

Farming (Pesticides) [Category: Industry]

AGRICULTURAL INSECTICIDE

FUMIGANT

RESEARCH CHEMICAL

Chemical and pharmaceutical intermediate.

(1979) No Data

(1981) No Data

(1979) No Data

(1981) No Data

(1979) NO EVIDENCE OF COMMERCIAL PRODN IN U.S.

(1981) NO EVIDENCE OF COMMERCIAL PRODN IN U.S.