Acetylthiourea

This compound is not very flammable but any fire involving this compound may produce dangerous vapors. You should evacuate the area. All firefighters should wear full-body protective clothing and use self-contained breathing apparatuses. You should extinguish any fires involving this chemical with a dry chemical, carbon dioxide, foam, or halon extinguisher. (NTP, 1992)

EYES: First check the victim for contact lenses and remove if present. Flush victim's eyes with water or normal saline solution for 20 to 30 minutes while simultaneously calling a hospital or poison control center. Do not put any ointments, oils, or medication in the victim's eyes without specific instructions from a physician. IMMEDIATELY transport the victim after flushing eyes to a hospital even if no symptoms (such as redness or irritation) develop.

SMALL SPILLS AND LEAKAGE: Should a spill occur while you are handling this chemical, you should dampen the solid spill material with alcohol, then transfer the dampened material to a suitable container. Use absorbent paper dampened with alcohol to pick up any remaining material. Seal the absorbent paper, and any of your clothes, which may be contaminated, in a vapor-tight plastic bag for eventual disposal. Solvent wash all contaminated surfaces with alcohol followed by washing with a strong soap and water solution. Do not reenter the contaminate area until the Safety Officer (or other responsible person) has verified that the area has been properly cleaned.

Generators of waste (equal to or greater than 100 kg/mo) containing this contaminant, EPA hazardous waste number P002, must conform with USEPA regulations in storage, transportation, treatment and disposal of waste.

A potential candidate for liquid injection incineration at a temperature range of 650 to 1600 °C and a residence time of 0.1 to 2 seconds. A potential candidate for rotary kiln incineration at a temperature range of 820 to 1600 °C and residence times of seconds for liquids and gases, and hours for solids. A potential candidate for fluidized bed incineration at a temperature range of 450 to 980 °C and residence times of seconds for liquids and gases, and longer for solids.

RECOMMENDED RESPIRATOR: Where the neat test chemical is weighed and diluted, wear a NIOSH-approved half face respirator equipped with a combination filter cartridge, i.e. organic vapor/acid gas/HEPA (specific for organic vapors, HCl, acid gas, SO2 and a high efficiency particulate filter).

TERRESTRIAL FATE: Based on a classification scheme(1), an estimated Koc value of 22(SRC), determined from a structure estimation method(2), indicates that 1-acetyl-2-thiourea is expected to have very high mobility in soil(SRC). Volatilization of 1-acetyl-2-thiourea from moist soil surfaces is not expected to be an important fate process(SRC) given an estimated Henry's Law constant of 2.6X10-11 atm-cu m/mole(SRC), using a fragment constant estimation method(3). 1-Acetyl-2-thiourea is not expected to volatilize from dry soil surfaces(SRC) based upon an estimated vapor pressure of 3.7X10-4 mm Hg(SRC), determined from a fragment constant method(4).

AQUATIC FATE: Based on a classification scheme(1), an estimated Koc value of 22(SRC), determined from an estimation method(2), indicates that 1-acetyl-2-thiourea is not expected to adsorb to suspended solids and sediment in water(SRC). Volatilization from water surfaces is not expected(3) based upon an estimated Henry's Law constant of 2.6X10-11 atm-cu m/mole(SRC), developed using a fragment constant estimation method(4). According to a classification scheme(5), an estimated BCF of 3.2(SRC), from an estimated log Kow of -0.27(6), suggests the potential for bioconcentration in aquatic organisms is low.

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), 1-acetyl-2-thiourea, which has an estimated vapor pressure of 3.7X10-4 mm Hg at 25 °C(2), is expected to exist solely in the vapor phase in the ambient atmosphere. Vapor-phase 1-acetyl-2-thiourea 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 10 hours(SRC), calculated from its rate constant of 3.8X10-11 cu cm/molecule-sec at 25 °C, determined using a structure estimation method(3). 1-Acetyl-2-thiourea (in a methanol solvent) absorbs UV light in the region between 290-330 nm(4); although the absorbance is relatively weak, there may be a potential for direct photolysis in the environment(SRC).

Using a structure estimation method based on molecular connectivity indices(1), the Koc for 1-acetyl-2-thiourea can be estimated to be 22(SRC). According to a classification scheme(2), this estimated Koc value suggests that 1-acetyl-2-thiourea is expected to have very high mobility in soil.

In the manufacture of rubber, irritant contact dermatitis may occur from a variety of acids, alkalis, detergents, and solvents used in the process. Allergic contact dermatitis occurs not infrequently and is almost always due to an organic accelerator or antioxidant. While the list of potential sensitizing accelerators and antioxidants is enormous, common allergens include ... thioureas. /Thioureas/

An estimated BCF of 3.2 was calculated for 1-acetyl-2-thiourea(SRC), using an estimated log Kow of -0.27(1,SRC) and a regression-derived equation(2). According to a classification scheme(3), this BCF suggests the potential for bioconcentration in aquatic organisms is low.

The Henry's Law constant for 1-acetyl-2-thiourea is estimated as 2.6X10-11 atm-cu m/mole(SRC) using a fragment constant estimation method(1). This Henry's Law constant indicates that 1-acetyl-2-thiourea is expected to be essentially nonvolatile(2). 1-Acetyl-2-thiourea is not expected to volatilize from dry soil surfaces(SRC) based upon an estimated vapor pressure of 3.7X10-4 mm Hg(3).

The rate constant for the vapor-phase reaction of 1-acetyl-2-thiourea with photochemically-produced hydroxyl radicals has been estimated as 3.8X10-11 cu cm/molecule-sec at 25 °C(SRC) using a structure estimation method(1). This corresponds to an atmospheric half-life of about 10 hours at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm(1). 1-Acetyl-2-thiourea has experimentally measured hydrolysis rate constants of 4.7X10-9 and 4.2X10-4 L/mole-sec at pH values of 7 and 11, respectively(2); and 7.1X10-5 L/mole-sec at a pH of 9.65(3). These rate constants correspond to half-lives of 4.6 years(2), 2.7 hours(SRC) and 0.46 hours(SRC) at pH values of 7, 9.65 and 11, respectively. The aqueous hydrolysis products of 1-acetyl-2-thiourea are acetic acid and thiourea(3). 1-Acetyl-2-thiourea (in a methanol solvent) absorbs UV light in the region between 290-330 nm(4); although the absorbance is relatively weak, there may be a potential for direct photolysis in the environment(SRC).

1-Acetyl-2-thiourea is not manufactured or used as an end-product industrially in the US. If released to air, an estimated vapor pressure of 3.7X10-4 mm Hg at 25 °C indicates 1-acetyl-2-thiourea will exist solely in the vapor phase in the ambient atmosphere. Vapor-phase 1-acetyl-2-thiourea will be degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals; the half-life for this reaction in air is estimated to be 10 hours. 1-Acetyl-2-thiourea absorbs UV light in the environmental spectrum; although the absorbance is relatively weak, there may be a potential for direct photolysis in the environment. If released to soil, 1-acetyl-2-thiourea is expected to have very high mobility based upon an estimated Koc of 22. Volatilization from moist soil surfaces is not expected to be an important fate process based upon an estimated Henry's Law constant of 2.6X10-11 atm-cu m/mole. No data are available regarding biodegradation in soil. If released into water, 1-acetyl-2-thiourea is not expected to adsorb to suspended solids and sediment in water based upon the estimated Koc. Volatilization from water surfaces is not expected to be an important fate process based upon this compound's estimated Henry's Law constant. An estimated BCF of 3.2 suggests the potential for bioconcentration in aquatic organisms is low. 1-Acetyl-2-thiourea has experimentally measured hydrolysis rate constants of 4.7X10-9, 7.1X10-5 and 4.2X10-4 L/mole-sec at pH values of 7, 9.65 and 11, respectively; these rate constants correspond to half-lives of 4.6 years, 2.7 hours and 0.46 hours, respectively. There are no data which suggests the general population is exposed to 1-acetyl-2-thiourea. (SRC)

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 ... . 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 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 patent can swallow, has a strong gag reflex, and does not drool. Administer activated charcoal ... . Cover skin burns with dry sterile dressings after decontamination ... . /SRP: Organic bases/amines and related compounds/

Advanced treatment: Consider orotracheal or nasotracheal intubation for airway control in the patient who is unconscious or has severe pulmonary edema. Positive-pressure ventilation techniques with a bag-valve-mask device may be beneficial. Monitor cardiac rhythm and treat arrhythmias as necessary ... . Start an IV with D5W TKO /SRP: "To keep open", minimal flow rate/. Use lactated Ringer's if signs of hypovolemia are present. Watch for signs of fluid overload. Administer 1% solution methylene blue if patient is symptomatic with severe hypoxia, cyanosis, and cardiac compromise not responding to oxygen. ... . Consider drug therapy for pulmonary edema ... . For hypotension with signs of hypovolemia, administer fluid cautiously. If patient is unresponsive to these measures, vasopressors may be helpful. Watch for signs of fluid overload ... . Treat seizures with diazepam (Valium) ... . Use proparacaine hydrochloride to assist eye irrigation ... . /SRP: Organic bases/amines and related compounds/

LD50 Rat oral 50 mg/kg

LD50 Mouse ip 100 mg/kg

P002; As stipulated in 40 CFR 261.33, when 1-acetyl-2-thiourea, as a commercial chemical product or manufacturing chemical intermediate or an off-specification commercial chemical product or a manufacturing chemical intermediate, becomes a waste, it must be managed according to federal and/or state hazardous waste regulations. Also defined as a hazardous waste is any container or inner liner used to hold this waste or any residue, contaminated soil, water, or other debris resulting from the cleanup of a spill, into water or on dry land, of this waste. Generators of small quantities of this waste may qualify for partial exclusion from hazardous waste regulations (40 CFR 261.5(e)).

Pursuant to section 8(d) of TSCA, EPA promulgated a model Health and Safety Data Reporting Rule. The section 8(d) model rule requires manufacturers, importers, and processors of listed chemical substances and mixtures to submit to EPA copies and lists of unpublished health and safety studies. Acetamide, N-(aminothioxomethyl)- is included on this list.

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 1000 lb or 454 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).