Semicarbazide hydrochloride

Prisms from dilute alcohol

White crystals

Very soluble (NTP, 1992)

Freely sol in water with acid reaction; very slightly sol in hot alcohol; Insol in anhyd ether

Insoluble in absolute alcohol

In water, 1X10+6 mg/L at 25 °C /Estimated/

9.2 [ug/mL] (The mean of the results at pH 7.4)

342 to 347 °F decomposes at 347-365 °F (EPA, 1998)

175-185 °C /decomposes/

MP: 96 °C /Base/

0.13 [mmHg]

0.13 mm Hg at 25 °C /Estimated/

Snow white crystals. Used as a reagent for ketones and aldehydes with which it affords crystalline compounds having characteristic melting points. (EPA, 1998)

White solid; [Hawley] White powder; [MSDSonline]

Ammonolysis with liquid NH3 gives 95% yield of free base

Hydroxyl radical reaction rate constant = 2X10-12 cu cm/molec-sec at 25 °C /Estimated/

This chemical does not meet GHS hazard criteria for 2.2% (2 of 93) of reports.

Danger

H301 (96.8%): Toxic if swallowed [Danger Acute toxicity, oral]

P203, P260, P264, P264+P265, P270, P280, P301+P316, P302+P352, P305+P351+P338, P305+P354+P338, P317, P318, P319, P321, P330, P332+P317, P337+P317, P362+P364, P405, and P501 (click each P-code to see the statement)

Aggregated GHS information provided per 93 reports by companies from 9 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.

Warning

Chemical: Hydrazinecarboxamide, monohydrochloride

Status: Active Update: 08-02-2021 https://echa.europa.eu/registration-dossier/-/registered-dossier/29438

Semicarbazide hydrochloride: 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.)

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. Semicarbazide hydrochloride is an extremely hazardous substance (EHS) subject to reporting requirements when stored in amounts in excess of its threshold planning quantity (TPQ) of 1,000/10,000 lbs.

Acute Tox. 3 (96.8%)

Acute toxicity (Oral) - Category 3

Hazardous to the aquatic environment (Acute) - Category 3

Signs and Symptoms of Semicarbazide Hydrochloride Exposure: No information on specific clinical effects of exposure to semicarbazide hydrochloride was found in available references. However, animal data indicate that signs and symptoms of acute exposure to semicarbazide hydrochloride may include loss of coordination, dizziness, tremors, convulsions, and seizures.

(Non-Specific -- Poisonous Solid, n.o.s.) Isolate hazard area. Stay upwind; keep out of low areas. Do not touch spilled material. Absorb small spills with sand or other noncombustible absorbent material and place into containers for later disposal. Take up small, dry spills with clean shovel; place material into clean, dry container and cover; move containers from spill area. Dike far ahead of large spills for later disposal. (EPA, 1998)

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.

9.1 [mg/m3]

100 [mg/m3]

600 [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)

EC50 Xenopus laevis (Clawed toad embryos; abnormal growth) 10,800 ug/L/96 hr (95% confidence interval: 9200-12,100); renewal

LC50 Xenopus laevis (Clawed toad embryos) ca. 6 g/L/96 hr, (95% confidence interval: 5.3-6.1 g/L); renewal

Semicarbazide is present in certain foods packaged in glass jars and bottles in very low quantities (ppb or ug/kg of food) due to migration from the plastic gasket which forms the airtight seal in the metal lid. Amount of up to 25 ppb have been found in baby foods, which give an estimate of intake of around 2 ug/kg bw/day as a worst case for infants /age 4-12 months/. /Semicarbazide/

Semicarbazide hydrochloride

Group 3: Not classifiable as to its carcinogenicity to humans

Volume 12: (1976) Some Carbamates, Thiocarbamates and Carbazides

1987

1987

/LABORATORY ANIMALS: Acute Exposure/ Administration of 200 mg/kg to acute spinal cats resulted in gradual and complete depression of dorsal root reflex and potential..., also decreased long-latency. Time course of these effects correlated with time course of induced depletion of gamma-aminobutyric acid in spinal cord.

/LABORATORY ANIMALS: Chronic Exposure or Carcinogenicity/ Fourteen chemicals of varied uses were tested for carcinogenicity by oral administration in male and female Charles River CD rats. ...Semicarbazide hydrochloride /was/ not carcinogenic under the test conditions.

/LABORATORY ANIMALS: Chronic Exposure or Carcinogenicity/ ... Admin to 25 male and 25 female 6-wk old Swiss mice for lifetime as 0.0625% solution in drinking water. Average daily intakes...3.3 mg/female and 4.8 mg/male. ... Tumors of vascular origin ... in 9/50 ... females, compared with 5/99 ... controls, and in 3/50 ... males, compared with 6/99 ... controls. ... Including 6 angiosarcomas and 2 angiomas of liver. ... In females, 37 lung tumors occurred in 25/50 ... compared with 31 in 21/99 female controls...no increase in incidence of lung tumors in treated males.

/LABORATORY ANIMALS: Chronic Exposure or Carcinogenicity/ ...6-8-wk old female DD mice were fed diet containing 0.1%...for 7 mo. at end of treatment, 8 survivors were killed and examined for lung tumors: 6 mice had total of 8 lung tumors, compared with 1 tumor in 20 controls.

For more Non-Human Toxicity Excerpts (Complete) data for SEMICARBAZIDE HYDROCHLORIDE (12 total), please visit the HSDB record page.

Biological half-lives were significantly different among the three acetylation phenotypes (analysis of variance, P < 0.05): 3.94+/-1.70 hours for slow acetylators, 2.25+/-0.37 hours for intermediate acetylators, and 1.86+/-0.67 hours for rapid acetylators. /Hydrazine/

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 ml/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 ... . /Hydrazine and Related Compounds/

Advanced treatment: Consider orotracheal or nasotracheal intubation for airway control in the patient who is unconscious, has severe pulmonary edema, or is in respiratory arrest. Positive pressure ventilation techniques with a bag valve mask device may be beneficial. 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. Consider drug therapy for pulmonary edema ... . For hypotension with signs of hypovolemia, administer fluid cautiously. Consider vasopressors for hypotension with a normal fluid volume. Watch for signs of fluid overload ... . Treat seizures with diazepam ... . Monitor for signs of hypoglycemia (decreased level of consciousness, tachycardia, pallor, dilated pupils, diaphoresis, and/or a dextrose strip or glucometer reading less than 50 mg/dl) and administer 50% dextrose if necessary. Draw blood sample before administration ... . Administer 1% solution methylene blue if patient is symptomatic with severe hypoxia, cyanosis, and cardiac compromise not responding to oxygen. ... . Use proparacaine hydrochloride to assist eye irrigation ... . /Hydrazine and Related Compounds/

LD50 Mouse oral 225 mg/kg

LD50 Mouse ip 145 mg/kg

LD50 Mouse sc 167 mg/kg

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. Semicarbazide hydrochloride is an extremely hazardous substance (EHS) subject to reporting requirements when stored in amounts in excess of its threshold planning quantity (TPQ) of 1,000/10,000 lbs.

Semicarbazide, a hydrazine derivative, is carcinogenic to mice but shows no or little mutagenicity in the Salmonella-microsome test. To clarify whether or not the genotoxic mechanism contributes to the non-mutagenic carcinogenicity of semicarbazide, ...DNA damage induced by semicarbazide /was investigated/ using 32P-5'-end-labeled DNA fragments obtained from the c-Ha-ras-1 protooncogene and the p53 tumor suppressor gene. Semicarbazide caused DNA damage frequently at the thymine and cytosine residues in the presence of Cu(II). Catalase and bathocuproine partially inhibited DNA damage, suggesting that hydrogen peroxide plus Cu(I) participates in DNA damage. When a high concentration of semicarbazide was used in the presence of catalase, DNA damage was induced, especially at G in 5'-AG and slightly at 5'-G in GG and GGG sequences. An electron paramagnetic resonance (EPR) spectroscopic study has confirmed that the reaction of semicarbazide with Cu(II) produces carbamoyl radicals (.CONH2), possibly generated via the nitrogen-centered radicals of semicarbazide. Azodicarbonamide also produced carbamoyl radicals and induced DNA damage frequently at 5'-G in GG and GGG sequences, suggesting that carbamoyl radicals participate in this sequence-specific DNA damage by semicarbazide. On the basis of... previous reports, ...the sequence-specific DNA damage at G in 5'-AG in the present study is due to the nitrogen-centered radicals. This study has shown that semicarbazide induces DNA damage in the presence of Cu(II) through the formation of hydrogen peroxide and Cu(I). In addition, semicarbazide-derived free radicals participate in DNA damage. DNA damage induced by these reactive species may be relevant to the carcinogenicity of semicarbazide. /Semicarbazide/

Used as a chemical reagent; [Hawley] Semicarbazide is a product of nitrofurazone metabolism; Its presence in biological specimens is an indicator of nitrofurazone use as an animal feed additive; [HSDB]

Farming (Feed Additives) [Category: Industry]

Reagent for ketones and aldehydes with which it affords crystal compound having characteristic melting points.

Isolation of hormones and isolation of certain fractions from essential oils.

.../Semicarbazide/ (SEM) is a known metabolite of the veterinary drug nitrofurazone and is used as an indicator for the use of the drug in food of animal origin. SEM has also been detected in seaweed derived products, which are widely used as food additives. /Semicarbazide/

Prepared by electrolytic reduction of nitrourea with cathodes of copper, nickel, lead, and mercury in hydrochloric acid solution

Commercial preparation from hydrazine hydrate, iron carbonyl, and carbon monoxide.

From hydrazine sulfate, potassium or sodium cyanate and sodium carbonate...

Hydrazinecarboxamide, hydrochloride (1:1): ACTIVE

First reported preparation ... was by reaction of benzylidenesemicarbazide with hydrochloric acid. ...method used for commercial production is not known.

...Semicarbazide (SEM) is a minor thermal decomposition product of the blowing agent azodicarbonamide (ADC).