Ammoniumthiocyanat

greater than 1.1 at 68 °F 1.1-1.15 at 20 °C (solution) (USCG, 1999)

1.3057 g/mL

1.305 @25 °C

Deliquescent crystals

Colorless, hygroscopic crystals

Very sol in water and ethanol; sol in acetone; insol in chloroform.

Highly sol in liquid ammonia and liquid sulfur dioxide, and mildly sol in acetonitrile

Freely sol in ethanol; sol in methanol, acetone; practically insol in CHCl3, ethyl acetate

When heated to decomposition it emits toxic fumes of /ammonia, nitric oxides, sulfur oxides, and hydrogen cyanide/

Decomposes from 70 °C onward.

320 °F (USCG, 1999)

149.6 °C

149.6 °C

Ammonium thiocyanate is a colorless crystalline solid. It is soluble in water. The primary hazard is the threat posed to the environment. Immediate steps should be taken to limit its spread to the environment. It is used in chemical analysis, in photography, as a fertilizer, and for many other uses.

Ammonium thiocyanate liquor appears as an aqueous solution of a colorless crystalline solid. Contains no cyanide and therefore has low acute toxicity. Prolonged exposure may produce skin eruptions and sometimes mild or severe disturbances of the nervous system. Primary hazard is threat posed to the environment. As a liquid, easily penetrates the soil to contaminate groundwater or nearby waterways. Used to make other chemicals, fertilizer, and for many other things.

Liquid; Large Crystals

Colorless crystals; [CAMEO]

This chemical does not meet GHS hazard criteria for 0.3% (1 of 347) of reports.

Danger

H302 (99.7%): Harmful if swallowed [Warning Acute toxicity, oral]

P261, P264, P264+P265, P270, P271, P273, P280, P301+P317, P302+P352, P304+P340, P305+P354+P338, P317, P321, P330, P362+P364, and P501 (click each P-code to see the statement)

Aggregated GHS information provided per 347 reports by companies from 21 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

Danger

Chemical: Thiocyanic acid, ammonium salt

Thiocyanic acid, ammonium salt (1:1) is listed on the EPA's Chemical Data Reporting (CDR) system. Manufacturers and importers of Thiocyanic acid, ammonium salt (1:1) are required to report information about their production and use of this chemical to the EPA under the Toxic Substances Control Act (TSCA). (40 eCFR Part 711)

Status: Active Update: 12-01-2023 https://echa.europa.eu/registration-dossier/-/registered-dossier/12671

Ammonium 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.)

Class 9

Class 9

Special Hazards of Combustion Products: Decomposes to form ammonia, hydrogen sulfide, and hydrogen cyanide. Oxides of nitrogen may also form. All of these products are toxic. (USCG, 1999)

Excerpt from ERG Guide 171 [Substances (Low to Moderate Hazard)]:

Inhalation of dust causes irritation of nose and throat. Ingestion causes dizziness, cramps, nervous disturbances. Dust irritates eyes. Can be absorbed through skin; prolonged contact may produce various skin eruptions, dizziness, cramps, nausea, and mild to severe disturbance of the nervous system. (USCG, 1999)

Excerpt from ERG Guide 171 [Substances (Low to Moderate Hazard)]:

Toxic by ingestion; A skin, eye, and respiratory tract irritant; [CAMEO] Ingested lethal dose in man is probably about 15-39 grams. [HSDB] Contact with strong acids or fire may generate sulfur dioxide, nitrogen oxides, cyanides, and hydrogen sulfide. [MSDSonline] See CYANIDES.

Salts, Acidic

Salts, Acidic

Ammonium thiocyanate is exempted from the requirement of a tolerance when used as an anjuvant/intensifier for defoliation of, and weed control in/on cotton and soybeans in accordance with good agricultural practice as inert (or occasionally active) ingredients in pesticide formulations applied to growing crops only.

AMMONIUM THIOCYANATE can release ammonia vapors if mixed with a chemical base or with an acid. Violent or explosive reactions have occurred when thiocyanates are mixed with oxidizing agents (such as chlorates(potassium chlorate), nitrates, nitric acid, and peroxides). Nitric acid violently oxidized a thiocyanate solution [Bretherick 1979 p. 121]. An explosion of guanidine nitrate demolished an autoclave built to withstand 50 atmospheres, in which it was being made from ammonium thiocyanate and lead nitrate [C. Angew. Chem. 49:23 1936].

AMMONIUM THIOCYANATE LIQUOR can release ammonia vapors if mixed with a chemical base or with an acid. Violent or explosive reactions have occurred when thiocyanates are mixed with oxidizing agents (such as chlorates(potassium chlorate), nitrates, nitric acid, and peroxides). Nitric acid violently oxidized a thiocyanate solution [Bretherick 1979 p. 121]. An explosion of guanidine nitrate demolished an autoclave built to withstand 50 atmospheres, in which it was being made from ammonium thiocyanate and lead nitrate [C. Angew. Chem. 49:23 1936].

Water soluble.

Freely soluble in water.

Excerpt from ERG Guide 171 [Substances (Low to Moderate Hazard)]:

Excerpt from ERG Guide 171 [Substances (Low to Moderate Hazard)]:

INHALATION: move to fresh air.

Excerpt from ERG Guide 171 [Substances (Low to Moderate Hazard)]:

Extinguish with water.

If material on fire or involved in fire: Extingiush fire using agent suitable for type of surrounding fire. (Material itself does not burn or burns with difficulty.)

/During fire fighting/ wear goggles and self-contained breathing apparatus.

A waste solution containing ammonium thiocyanate from a coke oven is sprayed into a combustion furnace and converted to gypsum by air oxidation.

Environmental considerations: Water spill: Neutralize with dilute acid or removable strong acid. Add calcium hypochlorite. Use mechanical dredges or lifts to remove immobilized masses of pollutants and precipitates.

Environmental considerations: Land spill: Dig a pit, pond, lagoon, or holding area to contain liquid or solid material. /SRP: If time permits, pits, ponds, lagoons, soak holes, or holding areas should be contained with a flexible impermeable membrane liner./ Cover solids with a plastic sheet to prevent dissolving in rain or fire fighting water.

Remove slowly into a large container of water. Add soda ash slightly by stirring. After 24 hr, decant or siphon into another container. Neutralize with 6M-HCl.

Excerpt from ERG Guide 171 [Substances (Low to Moderate Hazard)]:

Excerpt from ERG Guide 171 [Substances (Low to Moderate Hazard)]:

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.

If material not on fire and not involved in fire: Keep material out of water sources and sewers. Build dikes to contain flow as necessary.

Personnel protection: Keep upwind. ... Avoid breathing vapors. Wash away any material which may have contacted the body with copious amounts of water or soap and water.

SRP: Contaminated protective clothing should be segregated in such a manner so that there is no direct personal contact by personnel who handle, dispose, or clean the clothing. Quality assurance to ascertain the completeness of the cleaning procedures should be implemented before the decontaminated protective clothing is returned for reuse by the workers. Contaminated clothing should not be taken home at end of shift, but should remain at employee's place of work for cleaning.

SRP: The scientific literature for the use of contact lenses in industry is conflicting. The benefit or detrimental effects of wearing contact lenses depend not only upon the substance, but also on factors including the form of the substance, characteristics and duration of the exposure, the uses of other eye protection equipment, and the hygiene of the lenses. However, there may be individual substances whose irritating or corrosive properties are such that the wearing of contact lenses would be harmful to the eye. In those specific cases, contact lenses should not be worn. In any event, the usual eye protection equipment should be worn even when contact lenses are in place.

Excerpt from ERG Guide 171 [Substances (Low to Moderate Hazard)]:

Excerpt from ERG Guide 171 [Substances (Low to Moderate Hazard)]:

Ammonium thiocyanate is exempted from the requirement of a tolerance when used as an anjuvant/intensifier for defoliation of, and weed control in/on cotton and soybeans in accordance with good agricultural practice as inert (or occasionally active) ingredients in pesticide formulations applied to growing crops only.

15 [mg/m3]

25 [mg/m3]

150 [mg/m3]

Rubber or plastic gloves; rubber or plastic apron; standard goggles (USCG, 1999)

Excerpt from ERG Guide 171 [Substances (Low to Moderate Hazard)]:

Rubber or plastic gloves; rubber or plastic apron; standard goggles

Personnel protection: ... Wear boots, protective gloves, and goggles.

In cases of thiocyanate exposure, get fresh air and medical attention. If not breathing, give artificial respiration. If breathing is difficult, give oxygen. If swallowed, do not induce vomiting but give large quantities of water. Immediately flush skin with plenty of water for at least 15 minutes in case of exposure to skin or the eyes. (L217)

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)

Amitrole ... is highly active foliar systemic herbicide that translocates ... throughout plants and accumulates in growing points. It is highly toxic to wide range of grass and broadleaf annual and perennial species. ... /its/ efficacy ... can be enhanced by addition of ammonium thiocyanate as activator.

... In the presence of 50 mm ammonium thiocyanate, the potency of bicuculline to displace specifically bound (3)H-GABA was increased, with the magnitide of this increase being greater in some brain areas than others. Ammonium thiocyanate also increased the potency of bicuculline to inhibit GABA-activated benzodiazepine receptor binding, a biochemical measure of GABA receptor function. Ammonium thiocyanate selectively abolished the high affinity GABA-binding site without affecting either the low affinity component or GABA-activated benzodiazepine receptor binding.

Thiocyanates are known to affect the thyroid glands, reducing the ability of the gland to produce hormones that are necessary for the normal function of the body. Exposure to high levels of cyanide for a short time harms the brain and heart and can even cause coma and death. (L191)

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)

LC100 Salmo trutta (Brown trout) 200 mg/L /Conditions of bioassay not specified in source examined/

LC100 Lepomis macrochirus (Bluegill sunfish) 200 mg/L/1 hr /Conditions of bioassay not specified in source examined/

Oral (L191); inhalation (L191) ; dermal (L191)

Inhalation (L96) ; oral (L96) ; dermal (L96)

Thiocyanate (sulphocyanate or SCN) is believed to be a goitrogenic compound. It is a competitive inhibitor of the human thyroid sodium/iodide symporter NIS. Thus, the adverse effects of thiocyanate overload are especially noticeable when iodine availability is low. Intake of goitrogenic substances causes an adaptive increase in T3‰ЫЄs binding to brain nuclear receptors and in the activity of type II 5'-deiodinase, which generates T3 from T4. This altered function and availability of T3 is detrimental to the developing brain. Thiocyanate is also known to modulate activity of mammalian peroxidases. For instance, eosinophil peroxidase has been implicated in promoting oxidative tissue damage in a variety of inflammatory conditions, including asthma. Thiocyanate also acts as inhibitor to carbonic anhydrase, which catalyzes the rapid conversion of carbon dioxide to bicarbonate and protons. (A139, A143, A149) 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)

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)

Symptoms of thiocyanate exposure include rapid, deep breathing and shortness of breath, followed by convulsions (seizures) and loss of consciousness. (L191)

Cyanide poisoning is identified by rapid, deep breathing and shortness of breath, general weakness, giddiness, headaches, vertigo, confusion, convulsions/seizures and eventually loss of consciousness. (L96, L97)

/HUMAN EXPOSURE STUDIES/ Several acute fatalities have been reported, with death in 10-48 hr. /Thiocyanate salts/

/HUMAN EXPOSURE STUDIES/ Blood concentration of greater than 12% is to be considered dangerous. /Thiocyanates/

/SIGNS AND SYMPTOMS/ Inhalation of dust causes irritation of nose and throat. ...Dust irritates eyes.

/SIGNS AND SYMPTOMS/ ... True toxic manifestations of mild type are pyrosis, anorexia, nausea, abdominal distress and weakness. /Thiocyanates/

For more Human Toxicity Excerpts (Complete) data for AMMONIUM THIOCYANATE (6 total), please visit the HSDB record page.

No indication of carcinogenicity to humans (not listed by IARC).

No indication of carcinogenicity to humans (not listed by IARC).

Ammonium thiocyanate is exempted from the requirement of a tolerance when used as an anjuvant/intensifier for defoliation of, and weed control in/on cotton and soybeans in accordance with good agricultural practice as inert (or occasionally active) ingredients in pesticide formulations applied to growing crops only.

Persons in charge of vessels or facilities are required to notify the National Response Center (NRC) immediately, when there is a release of this designated hazardous substance, in an amount equal to or greater than its reportable quantity of 5000 lb or 2270 kg. The toll free number of the NRC is (800) 424-8802; In the Washington D.C. metropolitan area (202) 426-2675. The rule for determining when notification is required is stated in 40 CFR 302.4 (section IV. D.3.b).

Ammonium thiocyanate is designated as a hazardous substance under section 311(b)(2)(A) of the Federal Water Pollution Control Act and further regulated by the Clean Water Act Amendments of 1977 and 1978. These regulations apply to discharges of this substance. This designation includes any isomers and hydrates, as well as any solutions and mixtures containing this substance.

Thiocyanate is a potent inhibitor of iodide transport and is a competitive substrate for the thyroid peroxidase, but it does not appear to be concentrated in the thyroid. Blockage of the iodide trapping mechanism has a disruptive effect on the thyroid-pituitary axis, similar to iodine deficiency. The blood levels of T4 and T3 decrease, resulting in a compensatory increase in the secretion of TSH by the pituitary gland. The hypertrophy and hyperplasia of follicular cells following sustained exposure results in an increased thyroid weight and the development of goiter. /Thiocyanate/

Thiocyanates can appear in the body after metabolization of cyanides by rhodanese. When thiocyanates enter the body, they normally breaks down in aqueous solution to yield sulfate ions. However, thiocyanates are also found in the thyroid fluids. Immediately following exposure to thiocyanate containing solutions, the cystic fibrosis conductance regulator Cl‰ЫТ channel exhibits high unitary SCN‰ЫТ conductance and anomalous mole fraction behaviour. Thiocyanates is normally excreted in urine. (A140, A142, A143, A144) 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)

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)

The thiocyanate ion is slowly excreted in the urine; it is not decomposed to cyanide in appreciable quantities. /Thiocyanate salts/

The thiocyanate ion is slowly excreted in thr urine; it is not decomposed to cyanide in appreciable quantities. The thiocyanate ion readily diffuses into all tissues. It appears early in saliva and urine.

Can be absorbed through skin ... .

Therapeutic or normal level in human blood is 8.0-14.0 mg% or 80.0-140.0 ug/mL. /Thiocyanate/

Used in matches, fabric dyeing, photography, curing resins, chemical analysis, fertilizers, rocket propellants, adhesives, polymerization catalysts, herbicides, oil field tracers, electroplating, and pickling iron and steel; [HSDB]

Not currently registered as a pesticide in the United States; [HSDB]

Steel Producing [Category: Industry]

For Ammonium thiocyanate (USEPA/OPP Pesticide Code: 068200) there are 0 labels match. /SRP: Not registered for current use in the U.S., but approved pesticide uses may change periodically and so federal, state and local authorities must be consulted for currently approved uses./

In matches; double-dyeing fabrics; photography; improving and increased strength of silks weighted with tin salts; in producing grayish-black coating on Zn; mfr transparent artificial resins, thiourea; in pesticides; in determination and detection of small quantities of iron; determination of silver, mercury, etc.

In analytical chemistry; fertilizers; ingredient of freezing solution, especially liquid rocket propellants; adhesives; in curing resins; pickling iron and steel; electroplating; temporary soil sterilizer; polymerization catalyst; as weed killer and defoliant; separator of zirconium and hafnium, of gold and iron.

Maximum limits of impurities: Residue after ignition 0.01%; Insoluble matter 0.005%; chloride (Cl) 0.005%.

Maximum limits of trace impurities (in ppm): Heavy metals (as Pb) 5; Iron (Fe) 3.

GRADES: Technical; CP; 50 to 60 % solution.

Usual grade is 98-99% pure.

Grades or Purity: Reagent; Technical, 50-65% soln in water

Amitrole-T (union carbide); radazone TL was a mixture of amitrole and ammonium thiocyanate

For more Formulations/Preparations (Complete) data for AMMONIUM THIOCYANATE (10 total), please visit the HSDB record page.

All Other Chemical Product and Preparation Manufacturing

Thiocyanic acid, ammonium salt (1:1): ACTIVE

Ammonium thiocyanate capacity in the United States is well in excess of 9000 metric ton/yr on a 100% solids basis, but production in the 1990s is substantially less than its capacity.