Amitrole

Agrochemicals -> Pesticide active substances

Active substance -> EU Pesticides database: Not approved

Pesticides -> Herbicides, Other

Herbicides

log Kow= -0.97

-0.97

-0.87

1.138 at 68 °F (NTP, 1992) - Denser than water; will sink

1.138 at 20 °C

Relative density (water = 1): 1.14 (20 °C)

1.14

1.12 @ 20°C

1.14

greater than or equal to 100 mg/mL at 63.5 °F (NTP, 1992)

2.6X10+5 mg/L in ethanol at 75 °C. Slightly soluble in chloroform, acetonitrile, and ethyl acetate; and insoluble in acetone, ether, hydrocarbons

In water, 2.8X10+5 mg/L at 25 °C

Solubility in water, g/l at 25 °C: 280

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

(77 °F): 28%

Warning

H361d ***: Suspected of damaging the unborn child [Warning Reproductive toxicity]

P203, P260, P273, P280, P318, P319, P391, P405, and P501 (click each P-code to see the statement)

Warning

H361 (47.1%): Suspected of damaging fertility or the unborn child [Warning Reproductive toxicity]

P203, P260, P273, P280, P318, P319, P391, P405, and P501 (click each P-code to see the statement)

Chemical: 1H-1,2,4-Triazol-3-amine

Hazard Traits - Carcinogenicity

Commission Regulation (EU) No 1141/2010

1H-1,2,4-Triazol-5-amine is listed on the EPA's Chemical Data Reporting (CDR) system. Manufacturers and importers of 1H-1,2,4-Triazol-5-amine 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)

01/21/EC, 2010/77/EU, Reg (EU) 2015/408, Reg. (EU) 2015/1885, Reg. (EU) 2016/871, Reg. (EU) No 540/2011

Status: Active Update: 15-12-2021 https://echa.europa.eu/registration-dossier/-/registered-dossier/21685

Literature sources indicate that this compound is non-combustible. (NTP, 1992)

Combustible if powdered. Gives off irritating or toxic fumes (or gases) in a fire.

In the triazole class of herbicides, the known toxicity of amitrole is limited to slight irritant effects. [EPA Pesticides, p. 121] Classified as slightly toxic, it may be used only by certified applicators. [EXTOXNET] A weed control worker with allergic contact dermatitis was reported; [Kanerva, p. 783] Aminotriazole may be hepatotoxic on ingestion. [Zimmerman, p. 393] The following herbicides have an oral LD50 of >1 gm/kg and have little or no acute toxicity in humans: Alachlor, Amitrole, Ammonium sulfamate, Atrazine, Dalapon, Dicamba, Glyphosphate, Monuron, Oryzalin, Picloram, Propanil, Simazine, etc. [LaDou, p. 613] TLV basis: thyroid effects; [ACGIH]

The major hazards encountered in the use and handling of 2-amino-1,3,4-triazole stem from its toxicologic properties. Exposure to this odorless, colorless-to-white, crystalline substance may occur from its manufacture, handling, and use as a weed-killer. Effects from exposure may include dermal irritation, muscle spasms, shortness-of-breath, and anorexia. Also, the International Agency for Research on Cancer (IARC) has designated this substance as a Group 3 carcinogen, meaning, "The agent is not classifiable as to its carcinogenicity to humans." OSHA has set a Time Weighted Average (TWA) limit of 0.2 mg/cu m as a final rule to become effective December 31, 1992. In activities and situations where over-exposure may occur, wear a protective suit and a carefully fitted respirator. If contact should occur, irrigate exposed eyes with copious amounts of tepid water for at least 15 minutes, and wash exposed skin thoroughly with soap and water. Smoking, drinking, and eating should be prohibited in 2-amino-1,3,4-tiazole work areas, and cleanliness following the handling of this substance should be emphasized. While considered nonflammable, 2-amino-1,3,4-triazole will emit highly toxic fumes when strongly heated. 2-Amino-1,3,4-triazole should be kept in securely sealed containers, away from light (which will act to decompose the substance). Choice of container should take into consideration that 2-amino-1,3,4-triazole is mildly corrosive to iron, aluminum, copper, and copper alloys.

AMITROLE; WHO TECH REP SER (574): 3-49 (1975). REVIEW OF AMITROLE

National Toxicology Program. Eleventh Report on Carcinogens (2005). The Report on Carcinogens is an informational scientific and public health document that identifies and discusses substances (including agents, mixtures, or exposure circumstances) that may pose a carcinogenic hazard to human health. Amitrole (61-82-5) is listed as reasonably anticipated to be a human carcinogen.[Available from, as of July 31, 2009: http://ntp.niehs.nih.gov/ntp/roc/eleventh/profiles/s013amit.pdf]

USEPA/Office of Pesticide Programs; Reregistration Eligibility Decision Document - Amitrole. The RED summarizes the risk assessment conclusions and outlines any risk reduction measures necessary for the pesticide to continue to be registered in the U.S.[Available from, as of February 7, 2006: http://www.epa.gov/pesticides/reregistration/status.htm]

WHO; Environ Health Criteria 158: 2-Amino-1,3,4-Triazole (1994)

U011; As stipulated in 40 CFR 261.33, when amitrole, 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 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).

Section 8(a) of TSCA requires manufacturers of this chemical substance to report preliminary assessment information concerned with production, exposure, and use to EPA as cited in the preamble in 51 FR 41329.

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. Amitrole is included on this list.

Fires involving this chemical can be controlled with a dry chemical, carbon dioxide or Halon extinguisher. A water spray may also be used. (NTP, 1992)

Use water spray, foam, powder, carbon dioxide.

Fresh air, rest.

Remove contaminated clothes. Rinse skin with plenty of water or shower.

First rinse with plenty of water for several minutes (remove contact lenses if easily possible), then refer for medical attention.

Rinse mouth. Refer for medical attention .

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.

(General first aid procedures)

Store in an area without drain or sewer access. Separated from strong acids, strong oxidants, acid anhydrides and acid chlorides. Do NOT store or transport in containers made from iron, aluminium or copper and its alloys. Separated from food and feedstuffs.

Store at room temperature

PRECAUTIONS FOR "CARCINOGENS": Storage site should be as close as practical to lab in which carcinogens are to be used, so that only small quantities required for ... expt need to be carried. Carcinogens should be kept in only one section of cupboard, an explosion-proof refrigerator or freezer (depending on chemicophysical properties ...) that bears appropriate label. An inventory ... should be kept, showing quantity of carcinogen & date it was acquired ... . Facilities for dispensing ... should be contiguous to storage area. /Chemical Carcinogens/

Safe Storage of Pesticides. Always store pesticides in their original containers, complete with labels that list ingredients, directions for use, and first aid steps in case of accidental poisoning. Never store pesticides in cabinets with or near food, animal feed, or medical supplies. Do not store pesticides in places where flooding is possible or in places where they might spill or leak into wells, drains, ground water, or surface water.

PRECAUTIONS FOR "CARCINOGENS": A high-efficiency particulate arrestor (HEPA) or charcoal filters can be used to minimize amt of carcinogen in exhausted air ventilated safety cabinets, lab hoods, glove boxes or animal rooms ... Filter housing that is designed so that used filters can be transferred into plastic bag without contaminating maintenance staff is avail commercially. Filters should be placed in plastic bags immediately after removal ... . The plastic bag should be sealed immediately ... . The sealed bag should be labelled properly ... . Waste liquids ... should be placed or collected in proper containers for disposal. The lid should be secured & the bottles properly labelled. Once filled, bottles should be placed in plastic bags, so that outer surface ... is not contaminated ... . The plastic bag should also be sealed & labelled. ... Broken glassware ... should be decontaminated by solvent extraction, by chemical destruction, or in specially designed incinerators. /Chemical Carcinogens/

If a spill occurs, clean it up promptly. Don't wash it away. Instead, sprinkle the spill with sawdust, vermiculite, or kitty litter. Sweep it into a plastic garbage bag, and dispose of it as directed on the pesticide product label.

After Applying a Pesticide, Indoors or Outdoors. To remove pesticide residues, use a bucket to rinse tools or equipment three times, including any containers or utensils that you used when mixing the pesticide. Then pour the rinsewater into the pesticide sprayer and reuse the solution by applying it according to the pesticide product label directions. After applying any pesticide wash your hands and any other parts of your body that may have come in contact with the pesticide..To prevent tracking pesticides inside, remove or rinse your boots or shoes before entering your home. Wash any clothes that have been exposed to a lot of pesticide separately from your regular wash.

SMALL SPILLS AND LEAKAGE: If you spill this chemical, you should dampen the solid spill material with water, then transfer the dampened material to a suitable container. Use absorbent paper dampened with water to pick up any remaining material. Seal your contaminated clothing and the absorbent paper in a vapor-tight plastic bag for eventual disposal. Wash all contaminated surfaces with a soap and water solution. Do not reenter the contaminated area until the Safety Officer (or other responsible person) has verified that the area has been properly cleaned.

[40 CFR 240-280, 300-306, 702-799 (7/1/2005)] Generators of waste (equal to or greater than 100 kg/mo) containing this contaminant, EPA hazardous waste number U011, must conform with USEPA regulations in storage, transportation, treatment and disposal of waste.

Generators of waste (equal to or greater than 100 kg/mo) containing this contaminant, EPA hazardous waste number U011, must conform with USEPA regulations in storage, transportation, treatment and disposal of waste.

A potential candidate for rotary kiln incineration at a temperature range of 820 to 1,600 °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.

The following wastewater treatment technologies have been investigated for aminotriazole: Concentraction process: Biological treatment.

For more Disposal Methods (Complete) data for AMITROLE (11 total), please visit the HSDB record page.

Personal protection: particulate filter respirator adapted to the airborne concentration of the substance. Do NOT let this chemical enter the environment. Sweep spilled substance into covered sealable, plastic containers. If appropriate, moisten first to prevent dusting. Carefully collect remainder. Then store and dispose of according to local regulations.

PRECAUTIONS FOR "CARCINOGENS": Smoking, drinking, eating, storage of food or of food & beverage containers or utensils, & the application of cosmetics should be prohibited in any laboratory. All personnel should remove gloves, if worn, after completion of procedures in which carcinogens have been used. They should ... wash ... hands, preferably using dispensers of liq detergent, & rinse ... thoroughly. Consideration should be given to appropriate methods for cleaning the skin, depending on nature of the contaminant. No standard procedure can be recommended, but the use of organic solvents should be avoided. Safety pipettes should be used for all pipetting. /Chemical Carcinogens/

PRECAUTIONS FOR "CARCINOGENS": In animal laboratory, personnel should remove their outdoor clothes & wear protective suits (preferably disposable, one-piece & close-fitting at ankles & wrists), gloves, hair covering & overshoes. ... clothing should be changed daily but ... discarded immediately if obvious contamination occurs ... /also,/ workers should shower immediately. In chemical laboratory, gloves & gowns should always be worn ... however, gloves should not be assumed to provide full protection. Carefully fitted masks or respirators may be necessary when working with particulates or gases, & disposable plastic aprons might provide addnl protection. If gowns are of distinctive color, this is a reminder that they should not be worn outside of lab. /Chemical Carcinogens/

PRECAUTIONS FOR "CARCINOGENS": ... Operations connected with synth & purification ... should be carried out under well-ventilated hood. Analytical procedures ... should be carried out with care & vapors evolved during ... procedures should be removed. ... Expert advice should be obtained before existing fume cupboards are used ... & when new fume cupboards are installed. It is desirable that there be means for decreasing the rate of air extraction, so that carcinogenic powders can be handled without ... powder being blown around the hood. Glove boxes should be kept under negative air pressure. Air changes should be adequate, so that concn of vapors of volatile carcinogens will not occur. /Chemical Carcinogens/

PRECAUTIONS FOR "CARCINOGENS": Vertical laminar-flow biological safety cabinets may be used for containment of in vitro procedures ... provided that the exhaust air flow is sufficient to provide an inward air flow at the face opening of the cabinet, & contaminated air plenums that are under positive pressure are leak-tight. Horizontal laminar-flow hoods or safety cabinets, where filtered air is blown across the working area towards the operator, should never be used ... Each cabinet or fume cupboard to be used ... should be tested before work is begun (eg, with fume bomb) & label fixed to it, giving date of test & avg air-flow measured. This test should be repeated periodically & after any structural changes. /Chemical Carcinogens/

For more Preventive Measures (Complete) data for AMITROLE (18 total), please visit the HSDB record page.

... Effects on rat of 2 inhibitors ... on oxidation of methanol & ethanol to carbon dioxide, & on activities in vitro of rat-liver alcohol dehydrogenase & catalase. ... 3-amino-1,2,4-triazole considerably decreased ... carbon dioxide production from methanol ... & marginally ... from ethanol. ... There was additive effect ... when /used simultaneously with/ pyrazole ... .

3-amino-1,2,4-triazole administration (AT) at 3 and 6 hr led to the formation of round small vesicles from the rough endoplasmic reticulum, detachment of ribosomes, appearance of extensive areas of smooth endoplasmic reticulum, appearance of elongated and distorted mitochondria with an increase in the number of peroxisomes. The administration of carbon tetrachloride to AT-pretreated animals led to a mutual cancellation of the effects on the reticulum, & formation of myelin figures was prevented.

The placental transport of mercury in pregnant mice and its localization in the embryo and fetus from early organogenesis through the whole fetal period was studied by whole-body autoradiography and gamma counting. Preadmission to the dams of aminotriazole resulted in higher fetal concentration (esp in the liver) of mercury after inhalation of mercuric oxide but not after injection of (2+)mercury ion.

Inhalation of radioactive metallic mercury vapor in the mouse resulted in an accumulation of mercury in several organs where no specific uptake was observed after iv injection of inorganic mercury. Ethanol and aminotriazole (catalase inhibitors) decreased the concentration in several of these organs, although not in an exactly similar pattern. In the livers of non-treated animals most of the inhaled mercury accumulated in the hepatocytes in the periphery of the lobuli (periportal region), close to where the blood vessels enter the liver parenchyma. Treatment with aminotriazole increased the liver mercury content, with more or less all the hepatocytes apparently engaged in the oxidation of mercuric oxide.

For more Interactions (Complete) data for AMITROLE (9 total), please visit the HSDB record page.

LC50 /Coturnix japonica/ (Japanese quail) oral >5000 ppm (no mortality to 5000 ppm), age 12 days.

LC50 /Phasianus colchicus/ (Ring-necked pheasant) >5000 ppm (no mortality to 5000 ppm), age 10 days.

LC50 Gammarus fasciatus (Scud) >10 mg/L/96 hr at 18 °C /static conditions without aeration/

LC50 /Pimephales promelas/ (Fathead minnow, weight 1.2 g) >100 mg/L/96 hr at 18 °C. /static conditions without aeration/

For more Ecotoxicity Values (Complete) data for AMITROLE (29 total), please visit the HSDB record page.

TERRESTRIAL FATE: Based on a classification scheme(1), Koc values of 11.6, 29.7, 20.2, and 51.2, measured in four soils(2), indicates that 2-amino-1,3,4-triazole is expected to have high to very high mobility in soil(SRC). Volatilization of 2-amino-1,3,4-triazole from moist soil surfaces is not expected to be an important fate process(SRC) given an estimated Henry's Law constant of 2.2X10-13 atm-cu m/mole(SRC), derived from its vapor pressure, 4.4X10-7 mm Hg(2), and water solubility, 2.8X10+5 mg/L(2). 2-Amino-1,3,4-triazole is not expected to volatilize from dry soil surfaces(SRC) based upon its vapor pressure(2). Field dissipation studies and laboratory degradation studies indicate that 2-amino-1,3,4-triazole is not highly persistent in the environment(2). Aerobic biodegradation studies conducted under laboratory conditions indicated that the half-life of 2-amino-1,3,4-triazole in soil is approximately 22-26 days, while field dissipation studies conducted at sites in Oregon and Washington indicate a 50% dissipation time (DT50) of 17-21 days(2).

AQUATIC FATE: Based on a classification scheme(1), Koc values of 11.6 to 51.2(2), indicate that 2-amino-1,3,4-triazole is not expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is not expected(3) based upon an estimated Henry's Law constant of 2.2X10-13 atm-cu m/mole(SRC), derived from its vapor pressure, 4.4X10-7 mm Hg(2), and water solubility, 2.8X10+5 mg/L(2). According to a classification scheme(4), BCF values of less than 3 measured in fish(5), suggest bioconcentration in aquatic organisms is low(SRC). 2-Amino-1,3,4-triazole does not undergo hydrolysis or photolysis in aqueous systems, and the half-life of 2-amino-1,3,4-triazole was reported as 57-74 days in aerobic aquatic degradation studies(2).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), 2-amino-1,3,4-triazole, which has a vapor pressure of 4.4X10-7 mm Hg at 25 °C(2), is expected to exist in both the vapor and particulate phases in the ambient atmosphere. Vapor-phase 2-amino-1,3,4-triazole 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 3 days(SRC), calculated from its rate constant of 5.5X10-12 cu cm/molecule-sec at 25 °C(SRC) that was derived using a structure estimation method(3). Particulate-phase 2-amino-1,3,4-triazole may be removed from the air by wet and dry deposition(SRC).

...DISAPPEARANCE OF [5-(14)C]-AMITROLE FROM CORN PLANTS IN APPROX 6 WK WITH HALF-LIFE OF ABOUT 8 DAYS. DISAPPEARANCE WAS ALSO OBSERVED FROM SOYBEAN BUT @ MUCH SLOWER RATE.../&/ IN COTTON 4 DAYS AFTER TREATMENT.

2-Amino-1,3,4-triazole residues have been found in marketed cranberries (1958-1959)(1). 2-Amino-1,3,4-triazole is currently a non-food use herbicide used primarily in industrial areas (outdoors), non-agricultural rights-of-way, fencerows, hedgerows, non-agricultural uncultivated areas, soils, ornamental and/or shade trees, and ornamental shrubs and vines(2); therefore, residues on food products are not expected(SRC).

The substance can be absorbed into the body by inhalation of its aerosol.

inhalation, ingestion, skin and/or eye contact

/BIRDS and MAMMALS/ Acute symptoms: ataxia, weakness, slight wing drop, during first 3 days after single oral admin only in /mallard ducks/.

/AQUATIC SPECIES/ /Investigators/ exposed fry of bluegill sunfish, green sunfish and lake chub sucker fish to amitrole at 50 mg/liter for 8 days and reported no deaths. Young bluegill survived a 12-day exposure to 25 mg/liter, although some deaths occurred at higher concentrations.

/AQUATIC SPECIES/ /Investigators/ exposed yearling Coho salmon (Oncorhynchus kisutch) to Amitrole-T at concentrations of between 0.25 and 200 mg/liter. Transfer of the young salmon to sea water with comparable concentrations of amitrole increased the toxic effect of the compound; 56% of fish survived 336 hr in sea water containing 25 mg amitrole/liter and 12.5% survived 50 mg/liter. According to the authors, deaths occurred within 24-48 hr. Smoltification, the adaptation of young salmon to sea water, is under thyroid control. The goitrogenic properties of amitrole may explain the effect.

/OTHER TERRESTRIAL SPECIES/ Foliar and soil application in concentrations below the recommended rate of the herbicide 3-amino-1,2,4-triazole to the host plant Phaseolus vulgaris results in structural alteration of the protein-synthesizing apparatus of midgut and salivary gland cells of the phytophagous spider mite Tetranychus urticae (Acari: Tetranychidae) independent of its mode of application. With prolonged incubation times cytological defects become more intense, and spread to more cells and tissues. Resultant effects on yolk and egg formation were expressed as an inhibition of egg deposition that led to a decrease in the reproduction rat of Tetranychus urticae. ...

Redness.

Redness. Pain.

irritation eyes, skin; dyspnea (breathing difficulty), muscle spasms, ataxia, anorexia, salivation, increased body temperature; lassitude (weakness, exhaustion), skin dryness, depression (thyroid function suppression)

U011; As stipulated in 40 CFR 261.33, when amitrole, 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 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).

Section 8(a) of TSCA requires manufacturers of this chemical substance to report preliminary assessment information concerned with production, exposure, and use to EPA as cited in the preamble in 51 FR 41329.

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. Amitrole is included on this list.

Section 4(g)(2)(A) of FIFRA calls for the Agency to determine, after submission of relevant data concerning an active ingredient, whether products containing the active ingredients are eligible for reregistration. The Agency has previously identified and required the submission of the generic (i.e. active ingredient specific) data required to support reregistration of products containing Amitrole active ingredients. The Agency has completed its review of these generic data, and has determined that the data are sufficient to support reregistration of all products containing Amitrole.

As the federal pesticide law FIFRA directs, EPA is conducting a comprehensive review of older pesticides to consider their health and environmental effects and make decisions about their future use. Under this pesticide reregistration program, EPA examines health and safety data for pesticide active ingredients initially registered before November 1, 1984, and determines whether they are eligible for reregistration. In addition, all pesticides must meet the new safety standard of the Food Quality Protection Act of 1996. 2-Amino-1,3,4-triazole is found on List A, which contains most food use pesticides and consists of the 194 chemical cases (or 350 individual active ingredients) for which EPA issued registration standards prior to FIFRA '88. Case No: 0095; Pesticide type: herbicide; Registration Standard Date: 03/30/84; Case Status: RED Approved 09/96; OPP has made a decision that some/all uses of the pesticide are eligible for reregistration, as reflected in a Reregistration Eligibility Decision (RED) document .; Active ingredient (AI): 2-amino-1,3,4-triazole; Data Call-in (DCI) Date(s): 08/16/91, 12/24/96; AI Status: OPP has completed a Reregistration Eligibility Decision (RED) for the case/AI.

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 10 lb or 4.54 kg. The toll free number of the NRC is (800) 424-8802. The rule for determining when notification is required is stated in 40 CFR 302.4 (section IV. D.3.b).

Amitrole inhibits peroxidase activity in liver & thyroids, & mode of action in producing thyroid tumors appears to be related to goitrogenic effect of amitrole with resultant increased TSH (thyroid-stimulating hormone) ... .

This study demonstrated that the compound 3-amino-1,2,4-triazole is a strong inhibitor of erythrocyte glutathione peroxidase activity. Moreover, 3-amino-1,2,4-triazole inhibits arachidonic-induced malondialdehyde formation in platelet-rich plasma and prostacyclin-like activity generation in aorta rings. These results give new lines of evidence on the connection between glutathione peroxidase activity and prostaglandin synthesis in rat platelets and arterial vessel walls.

A technique for the cytochemical demonstration of peroxidase activity in unfixed guinea-pig thyroid tissue is described. Both 3-amino-1,2,4-triazole and methimazole inhibited peroxidase activity in the follicle cells (enzyme activity was still seen in the erythrocytes), maximal inhibition occurring at 10 mmol.

Interference with histidine metabolism, inhibition of pigment biosynthesis, or both have been the principal candidates for the primary site of action of 3-amino-1,2,4-triazole (amitrole). Arabidopsis thaliana is sensitive to 1,2,4-triazole-3-alanine, a feedback inhibitor of histidine biosynthesis, and this effect is reversed by histidine. The combination of triazolealanine and histidine, however, does not reverse the herbicical effect of amitrole. This indicates that amitrole toxicity is not caused by histidine starvation, nor is it caused by the accumulation of a toxic intermediate of the histidine pathway. Amitrole inhibits root elongation at lower concentrations than it causes pigment bleaching in the leaves. In contrast, fluridone, a known inhibitor of the carotenoid biosynthetic pathway does not block root elongation. Fluridone also inhibits carotenoid accumulation in etiolated seedlings in the dark, but amitrole does not. Last, gabaculine and acifluorfen, but not amitrole, prevent chlorophyll accumulation in greeting etiolated seedlings of Arabidopsis. ...

For more Mechanism of Action (Complete) data for AMITROLE (8 total), please visit the HSDB record page.

Two groups of five male and five female Sprague-Dawley rats weighing 200-250 g were exposed (either nose only or whole body) to atmospheres of 5-14C-amitrole (radiochemical purity > 97%) in water aerosols at concentrations in air of 49.2 ug/liter (2.6 uCi/liter) or 25.8 ug/liter (1.4 uCi/liter), respectively, for 1 hr, and then observed for 120 hr. The particle size distribution of the aerosols was not reported. The calculated elimination half-life of radioactivity was approximately 21 hr for both exposures; approximately 75% of the radioactivity was eliminated in the urine within 12 hr.

Rats (5/sex; Charles River Ltd.) were exposed by inhalation to an estimated dose of 25.8 ug/L for "whole body" or 49.2 ug/L for "head only" radiolabelled amitrole for one hour. Blood samples were taken at specified intervals and urine, feces and carcasses were examined for radioactivity. ...The blood plasma half life was estimated to be 20 hours.

After 39-yr-old woman ingested 20 mg/kg of aminotriazole, urine taken some hours later contained unchanged aminotriazole (100 mg/100 mL). No metabolites were found.

Metabolism... in plants: Glycine and serin of plants are utilized in biosynthesis of beta-(3-amino-S-triazolyl-1-)alpha-alanine.

In... studies with Canada thistle, 3 compounds ... observed. One was identified as beta-(3-amino-1,2,4-triazolyl-1)-alpha-alanine).

Major metabolic product formed from amitrole by microbiological activity was carbon dioxide. ... E coli converted 3-ATA into metabolite, 3-amino-1,2,4,-triazolyl alanine.

For more Metabolism/Metabolites (Complete) data for AMITROLE (10 total), please visit the HSDB record page.

Substances that contain a fused three-ring moiety and are used in the treatment of depression. These drugs block the uptake of norepinephrine and serotonin into axon terminals and may block some subtypes of serotonin, adrenergic, and histamine receptors. However, the mechanism of their antidepressant effects is not clear because the therapeutic effects usually take weeks to develop and may reflect compensatory changes in the central nervous system.

Compounds or agents that combine with an enzyme in such a manner as to prevent the normal substrate-enzyme combination and the catalytic reaction.

A subclass of analgesic agents that typically do not bind to OPIOID RECEPTORS and are not addictive. Many non-narcotic analgesics are offered as NONPRESCRIPTION DRUGS.

Drugs that block the transport of adrenergic transmitters into axon terminals or into storage vesicles within terminals. The tricyclic antidepressants (ANTIDEPRESSIVE AGENTS, TRICYCLIC) and amphetamines are among the therapeutically important drugs that may act via inhibition of adrenergic transport. Many of these drugs also block transport of serotonin.

Aminotriazole was applied to skin of rabbits. After 15 min it had penetrated into the blood. Fat was ... /an/ inconsequential site of storage.

Wistar rats were fed 1 mg 14C-amitrole (per rat) via stomach tube. The expired air, urine, feces and tissues were analyzed for radioactivity during a three day period following dosing. During the first 24 hours, 70 to 95.5% of the radioactivity was found in the urine; a small variable amount of activity was found in the feces. After absorption, amitrole was distributed throughout most body tissues. The maximum radioactivity was found in liver and kidney. Within three to four hours of dosing, the tissue levels began decreasing. Paper chromatography revealed both unchanged amitrole and one unidentified metabolite in rat liver slices taken at various times following dosing.

Primary routes of exposure are skin, eye contact and inhalation of powders, liquids, and sprays.

Anesthetized animals were allowed to inhale through a tracheal cannula liquid aerosols of drug solutions generated with an air-jet nebulizer. The aerosols had a mass median aerodynamic diameter of 2.81 um and a geometric standard deviation of 2.53. The time necessary for 50% absorption of amitrole was 1.3 min. Comparison with previously reported absorption rates measured after intratracheal injection of 0.1 mL of drug solution showed that drug inhaled as an aerosol was absorbed roughly 2 times more rapidly than when administered by intratracheal injection.

For more Absorption, Distribution and Excretion (Complete) data for AMITROLE (11 total), please visit the HSDB record page.

Used control grasses, broadleafs, poison ivy, and aquatic weeds. [EXTOXNET]

Use on food crops was canceled by the EPA in 1971; [EXTOXNET]

For 2-amino-1,3,4-triazole (USEPA/OPP Pesticide Code: 004401) ACTIVE products with label matches. /SRP: Registered for 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./

Broadleaf weeds, annual grasses, poison ivy in noncropland; semi-aquatic weeds in marshes, drainage ditches.

/Herbicide/ for perennial broadleaf weeds & grasses in non-cropped areas ... some aquatic weeds ... . Used in mixture with more persistent herbicides for general weed control in non-cropped areas & as directed spray in ornamental nurseries.

... Plant growth regulator; feedstock for chemical synthesis

(1978) 5.38X10+8 G

(1982) 2.11X10+8 G

(1985) 2.63X10+8 G

2023: <50,000 lb

(1978) NOT PRODUCED COMMERCIALLY IN USA

(1982) NOT PRODUCED COMMERCIALLY IN USA

(1990) 10 thousand-500 thousand pounds

Allen, US 2670282 (1954 to American Chemical Paint co.)

Reaction of aminoguanidine with formic acid.

From formylguanine nitrate & sodium carbonate; heating s-triazine to 120 °C in presence of aminoguanidine.

Cyclization /of aminoguanidine/ with formic acid produces 3-amino-1,2,4-triazole

Amitrole is synthesized by condensing formic acid with aminoguanidine and can be purified by recrystallization from methanol.

Amizine is trade name for mixture of amitrole & simazine ... and fenamine refers to combination of amitrole, fenac & atrazine.

... Kleer-lot (mixture of amitrole & linuron) ... .

Amino triazole weedkiller 90 is dry soluble powder formulation containing 90% active ingredient. Cytrol amitrole-t liquid weedkiller is water soluble formulation containing 2 lbs amino triazole plus 19% ammonium thiocyanate/gal.

Pure, technical grades

For more Formulations/Preparations (Complete) data for AMITROLE (9 total), please visit the HSDB record page.

Food Contaminant -> CONTAMINANT -> JECFA Functional Classes

Herbicides

HERBICIDES

All Other Chemical Product and Preparation Manufacturing

1H-1,2,4-Triazol-5-amine: ACTIVE

Foliage spray on weeds. Rates: 2 to 10 lb/acre. Usual carrier: water--20 to 200 gal/acre; water-soluble. /Former use/

Suitable for use with hard water. Not intended for mixing with other pesticides & fertilizers.

All registered uses of amitrole on food crops were cancelled in 1971 /in USA/.

Not registered for use on food crops. ... Industrial areas (outdoor), non-agricultural rights-of-way/fence rows/ hedge rows, non-agricultural uncultivated areas/soils, ornamental and/or shade trees, ornamental shrubs and vines.