Triclopyr

Fresh air, rest.

Remove contaminated clothes. Rinse and then wash skin with water and soap.

Rinse with plenty of water for several minutes (remove contact lenses if easily possible).

Rinse mouth.

Suitable extinguishing media: Use water spray, alcohol-resistant foam, dry chemical or carbon dioxide.

Advice for firefighters: Wear self contained breathing apparatus for fire fighting if necessary.

Keep container tightly closed in a dry and well-ventilated place.

Keep in the dark.

Store above 35 °F. Agitate before use if stored near freezing.

ACCIDENTAL RELEASE MEASURES: Personal precautions, protective equipment and emergency procedures: Use personal protective equipment. Avoid dust formation. Avoid breathing vapors, mist or gas. Ensure adequate ventilation. Avoid breathing dust. Environmental precautions: Do not let product enter drains. Methods and materials for containment and cleaning up: Pick up and arrange disposal without creating dust. Sweep up and shovel. Keep in suitable, closed containers for disposal.

Personal protection: particulate filter respirator adapted to the airborne concentration of the substance. Sweep spilled substance into covered containers. Wash away remainder with plenty of water.

SRP: 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 air, soil or water; effects on animal, aquatic and plant life; and conformance with environmental and public health regulations. If it is possible or reasonable use an alternative chemical product with less inherent propensity for occupational harm/injury/toxicity or environmental contamination.

Product: Offer surplus and non-recyclable solutions to a licensed disposal company; Contaminated packaging: Dispose of as unused product.

ACCIDENTAL RELEASE MEASURES: Personal precautions, protective equipment and emergency procedures: Use personal protective equipment. Avoid dust formation. Avoid breathing vapors, mist or gas. Ensure adequate ventilation. Avoid breathing dust. Environmental precautions: Do not let product enter drains.

Precautions for safe handling: Avoid contact with skin and eyes. Avoid formation of dust and aerosols. Provide appropriate exhaust ventilation at places where dust is formed. Normal measures for preventive fire protection.

Appropriate engineering controls: Handle in accordance with good industrial hygiene and safety practice. Wash hands before breaks and at the end of workday.

Gloves must be inspected prior to use. Use proper glove removal technique (without touching glove's outer surface) to avoid skin contact with this product. Dispose of contaminated gloves after use in accordance with applicable laws and good laboratory practices. Wash and dry hands.

For more Preventive Measures (Complete) data for Triclopyr (7 total), please visit the HSDB record page.

The purpose of this study was to determine the neurotoxicity of two commonly used herbicides: picloram and triclopyr and the neuroprotective effects of the mitochondria-targeted antioxidant, SS31. Using mouse neuroblastoma (N2a) cells and primary neurons from C57BL/6 mice, we investigated the toxicity of these herbicides, and protective effects of SS31 peptide against picloram and triclopyr toxicity. We measured total RNA content, cell viability and mRNA expression of peroxiredoxins, neuroprotective genes, mitochondrial-encoded electron transport chain (ETC) genes in N2a cells treated with herbicides and SS31. Using primary neurons from C57BL/6 mice, neuronal survival was studied in neurons treated with herbicides, in neurons pretreated with SS31 plus treated with herbicides, neurons treated with SS31 alone, and untreated neurons. Significantly decreased total RNA content, and cell viability in N2a cells treated with picloram and triclopyr were found compared to untreated N2a cells. Decreased mRNA expression of neuroprotective genes, and ETC genes in cells treated with herbicides was found compared to untreated cells. Decreased mRNA expression of peroxiredoxins 1-6 in N2a cells treated with picloram was found, suggesting that picloram affects the antioxidant enzymes in N2a cells. Immunofluorescence analysis of primary neurons revealed that decreased neuronal branching and degenerating neurons in neurons treated with picloram and triclopyr. However, neurons pretreated with SS31 prevented degenerative process caused by herbicides. Based on these results, we propose that herbicides picloram and triclopyr appear to damage neurons, and the SS31 peptide appears to protect neurons from herbicide toxicity.

LD50; Species: Anas platyrhynchos (Mallard duck) oral via capsule 1,698 mg/kg (95% confidence interval: 1204-2394 mg/kg)

LC50; Species: Anas platyrhynchos (Mallard duck) dietary >5620 ppm for 8 days

LC50; Species: Coturnix japonica (Japanese quail) dietary 3,278 ppm for 8 days

LC50; Species: Colinus virginianus (Northern Bobwhite quail) dietary 2,935 ppm for 8 days

For more Ecotoxicity Values (Complete) data for Triclopyr (27 total), please visit the HSDB record page.

TERRESTRIAL FATE: Based on a classification scheme(1), Koc values of 12 to 134(2), indicate that triclopyr is expected to have very high to high mobility in soil(SRC). The pKa of triclopyr is 2.68(3), indicating that this compound will exist almost entirely in the anion form in the environment and anions generally do not adsorb strongly to soils containing organic carbon and clay relative to their neutral counterpart(4). Volatilization of triclopyr from moist soil surfaces is not expected to be an important fate process(SRC) given an estimated Henry's Law constant of 9.7X10-10 atm-cu m/mole(SRC), based upon its vapor pressure, 1.26X10-6 mm Hg(3), and water solubility, 440 mg/L(3). Triclopyr is not expected to volatilize from dry soil surfaces(SRC) based upon its vapor pressure(3). Additionally, the pKa indicates triclopyr will exist almost entirely in the anion form at pH values of 5 to 9 and, therefore, volatilization from moist or dry soil surfaces is not expected to be an important fate process. Under aerobic conditions, triclopyr biodegrades with half-lives of 1.4 to 69 days in various soils(4,5). Triclopyr has an aerobic half-life of 142 days in a soil:water system(4). Triclopyr is persistent under anaerobic conditions with a half-life of approx 1,300 days(4). These data indicate that biodegradation may be an important environmental fate process under certain conditions in soil(SRC).

TERRESTRIAL FATE: The mean disappearance half-life of triclopyr on four soils was 138 days (range, 9-314 days)(1). The dissipation rate of triclopyr depended on temperature (positive relationship) and organic matter content (inverse relationship) but not on water potential(1). Also the dissipation rate was slower in the subsurface than at the surface(1). When sunlight is removed as a dissipation mechanism for triclopyr, the disappearance of triclopyr slows dramatically(1).

AQUATIC FATE: Based on a classification scheme(1), Koc values of 12 to 134(2), indicate that triclopyr 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 of 9.7X10-10 atm-cu m/mole(SRC), based upon its vapor pressure, 1.26X10-6 mm Hg(4), and water solubility, 440 mg/L(4). A pKa of 2.68(4) indicates triclopyr will exist almost entirely in the anion form at pH values of 5 to 9 and, therefore, volatilization from water surfaces is not expected to be an important fate process(SRC). According to a classification scheme(5), BCF values of 0.6 to 31(6), suggests the potential for bioconcentration in aquatic organisms is low(SRC). Triclopyr has an aerobic half-life of 142 days in a soil:water system, indicating that biodegradation may be a slow environmental fate process under certain conditions in water(7).

ATMOSPHERIC FATE: According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere(1), triclopyr, which has a vapor pressure of 1.26X10-6 mm Hg at 25 °C(2), will exist in both the vapor and particulate phases in the ambient atmosphere. Vapor-phase triclopyr 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 2.2 days(SRC), calculated from its rate constant of 4.8X10-12 cu cm/molecule-sec at 25 °C(SRC) that was derived using a structure estimation method(3). Particulate-phase triclopyr may be removed from the air by wet and dry deposition(SRC). Triclopyr contains chromophores that absorb at wavelengths >290 nm(4) and, therefore, may be susceptible to direct photolysis by sunlight. Triclopyr has photodegradation half-lives of less than 12 hours to 1.7 days,(5,6).

Occupational hepatotoxin - Secondary hepatotoxins: the potential for toxic effect in the occupational setting is based on cases of poisoning by human ingestion or animal experimentation.；Skin Sensitizer - An agent that can induce an allergic reaction in the skin.

IDENTIFICATION AND USE: Triclopyr is a solid. It is used as an herbicide that acts via the auxin system in plants. HUMAN EXPOSURE AND TOXICITY: Triclopyr is irritating to skin and eyes. One case report describes patient who ingested triclopyr and developed metabolic acidosis and coma with cardiovascular impairment. ANIMAL STUDIES: In male mice, triclopyr (480 mg/kg/day) caused single cell necrosis of the liver, significant increases in alkaline phosphatase, aspartate transaminase, and alanine transaminase, and enlargement of the liver with dark color. Centrilobular swelling and degeneration of hepatocytes were observed in a dose-dependent fashion at 120 mg/kg/day and above in male mice, along with mild increases in liver enzymes at 240 mg/kg/day. Degeneration of the proximal tubules of the kidneys of male and female rats was observed in increased incidence at 20 mg/kg/day and above for both sexes. Absolute and relative kidney weight was significantly increased in male rats at the 50 mg/kg/day dose, while relative kidney weight was increased in male and female rats at 250 mg/kg/day. In a chronic toxicity/carcinogenicity study in mice, there were no compound-related tumors observed in male mice. Female mice had a significant increasing trend in mammary gland adenocarcinomas. In an Ames assay, the mutagenic potential of triclopyr was negative in Salmonella tester strains TA-1535, TA-1537, TA-1538, TA-98, and TA-100 in the absence and presence of metabolic activation. Rats maintained on diets supplying 0, 3, 10, or 30 mg/kg/day over three generations exhibited no consistent treatment-related effects on reproductive performance, pregnancy, parturition, or neonatal survival. ECOTOXICITY STUDIES: Experiments on zebrafish embryos demonstrated that 3,5,6-trichloro-2-pyridinol, a metabolite of triclopyr, appears to be more toxic during development compared to the parent compound.

/BIRDS and MAMMALS/ ... In the sublethal effects experiment, when birds were exposed to 500 mg/kg triclopyr butoxyethyl ester (TBEE) in the diet for 29 days, food consumption and body weight were significantly depressed (P<0.05). Similar prolonged exposures to 50 and 150 mg/kg TBEE in the diet had no significant effect on food consumption or body weight (P>0.05). Perch-hopping activity was depressed relative to controls in the 500 mg/kg group, and elevated in the 150 mg/kg group, but neither of these differences was significant (P>0.05). Disappearance of TBEE residues from treated seeds over the 29 day experimental period followed an exponential decay model, with half-lives in the order of 15 to 18 days. On the basis of our observation that TBEE had no significant adverse effects at a concentration greater than the maximum expected environmental concentration, we propose that forestry applications of triclopyr at registered dosage rates pose little risk to wild songbirds. /Triclopyr butoxyethyl ester/

/AQUATIC SPECIES/ Estrogenic potencies of four herbicides (triclopyr, 2,4-dichlorophenoxyacetic acid (2,4-D), diquat dibromide, glyphosate), two alkylphenol ethoxylate-containing surfactants (R-11 and Target Prospreader Activator (TPA)), and the binary mixture of surfactants with the herbicides were evaluated using an in vivo rainbow trout vitellogenin (Vtg) assay. Juvenile rainbow trout exposed to 2,4-D (1.64 mg/L) for 7 days had a 93-fold increase in plasma Vtg levels compared with untreated fish, while rainbow trout exposed to other pesticides alone did not show elevated vitellogenin levels compared to the control fish. When combined with surfactants, trends indicated enhanced estrogenicity for all combinations, but only 2,4-D and triclopyr caused significant induction of Vtg. Concentration-response studies demonstrated that the lowest observed effect concentrations (LOECs) for 2,4-D and triclopyr were 0.164 mg/L and 1 mg/L, respectively. In terms of measured 4-nonylphenol (4-NP), the LOECs of R-11 and TPA were 20 ug/L and 9.5 ug/L, respectively. Binary mixtures of TPA and 2,4-D showed a greater than additive estrogenic response at the lowest concentrations tested, but a less than additive response at the highest combined concentrations. Binary mixtures of TPA with triclopyr also caused greater than additive Vtg responses in two middle concentrations when compared to TPA or triclopyr alone. When trout were exposed to water collected from a site where triclopyr was used in combination with TPA, a concentration-dependent increase in Vtg expression was observed. Measured values of 4-NP were 3.7 ug/L, and triclopyr concentrations were below detection (<5 ng/L). Estradiol equivalents (EEQs) of the lake water were calculated from an estradiol concentration-response curve and were similar (8.5 +/- 7.7 ng/L) to the mean values for the combined triclopyr + TPA treatments (9.9-12.2 ng/L) in the laboratory, suggesting the estrogenicity of the water may have been due to the

Cough.

Redness.

Redness.

EPA has released the Interactive Chemical Safety for Sustainability (iCSS) Dashboard. The iCSS Dashboard provides an interactive tool to explore rapid, automated (or in vitro high-throughput) chemical screening data generated by the Toxicity Forecaster (ToxCast) project and the federal Toxicity Testing in the 21st century (Tox21) collaboration. /The title compound was tested by ToxCast and/or Tox21 assays/[USEPA; ICSS Dashboard Application; Available from, as of December 8, 2016: http://actor.epa.gov/dashboard/]

Based on adsorption/desorption studies using sand, sandy loam, silt loam, and clay loam, triclopyr was considered mobile in soils; Koc values for triclopyr range from 12 to 134 at pH values of 5.0 to 7.7(1,2). Kd values ranged from 0.165 to 0.975 mL/g (pH 5.0 to 7.7)(1,2). Freundlich sorption constants(Kf) evaluated on four soils, 2 silty loams and 2 silty clays, ranged from 0.54 to 1.73 and relative sorption coefficient(Kd) values for triclopyr evaluated on the four soils ranged from 0.08 to 0.61 mL/g (pH 5 to 7)(3). From sorption studies on two soil types, triclopyr has Koc values of 14 and 66 days in clay soils with high organic matter(pH 6.3) and loamy-clay with less organic matter(pH 5.1), respectively(4). These data indicate that pH and organic matter influenced sorption and the mobility of triclopyr was greatest in soils with the higher pH(3,4). Koc values reported for its major degradation product, trichloropyridinol, are 77 to 242(1,5). According to a classification scheme(6), these Koc data suggest that triclopyr will have high to very high mobility in soil(SRC).

Regulation (EC) No 396/2005 (amended)

PMN - indicates a commenced PMN (Pre-Manufacture Notices) substance.

Triclopyr is listed in the dataset of EPA Human Health Benchmarks for Pesticides under the Safe Drinking Water Act (40 eCFR 141)

2006/74/EC, Reg (EU) 2020/421, Reg. (EU) 2018/524, Reg. (EU) 2015/307, Reg. (EU) 2019/168, Reg. (EU) 2021/566, Reg. (EU) 2022/378, Reg. (EU) 2023/689, Reg. (EU) 2024/2221, Reg. (EU) No 540/2011, Reg. (EU) No 878/2014

Triclopyr: HSNO Approval: HSR003256 Approved with controls

Tolerances are established for residues of the herbicide triclopyr, including its metabolites and degradates, in or on the commodities in the table below resulting from the application of the butoxyethyl ester of triclopyr, triethylamine salt of triclopyr, or choline salt of triclopyr. Compliance with the tolerance levels specified below is to be determined by measuring only triclopyr, 2-[(3,5,6-trichloro-2-pyridinyl)oxy]acetic acid.[Table#6692]

Tolerances are established for residues of the herbicide triclopyr, including its metabolites and degradates, in or on the commodities in the table below resulting from the application of the butoxyethyl ester of triclopyr, triethylamine salt of triclopyr, or choline salt of triclopyr. Compliance with the tolerance levels specified below is to be determined by measuring the combined residues of triclopyr, 2-[(3,5,6-trichloro-2-pyridinyl)oxy]acetic acid, and its metabolite 3,5,6-trichloro-2-pyridinol (TCP), calculated as the stoichiometric equivalent of triclopyr.[Table#6693]

Based on the reviews of the generic data for the active ingredient triclopyr, the Agency has sufficient information on the health effects of triclopyr and on its potential for causing adverse effects in fish and wildlife and the environment. The Agency has determined that triclopyr products, labeled and used as specified in this Reregistration Eligibility Decision, will not pose unreasonable risks of adverse effects to humans or the environment. Therefore, the Agency concludes that products containing triclopyr for all uses are eligible for reregistration.

New Active Ingredients ... includes pesticide active ingredients initially registered after November 1, 1984, that currently have active product registrations. By law, these newer pesticides are not subject to the reregistration program. They must, however, meet the new safety standard of the FQPA, and will be reviewed on a 15-year cycle under the registration review program. ... Active Ingredient Number: 116001; Type of Pesticide: conventional - herbicide; Use Site: non-food use, turf, grasses; Year: 1997.

Used as herbicide to control woody plants and broad-leaved weeds in uncultivated land, industrial areas, coniferous forests, plantation crops, and rice fields; [HSDB] Used on rights-of-way, pastures, rangelands, forests, rice, and turf, including home lawns; [Reference #1]

No current active registrations in the US for the free acid; [Reference #1]

Farming (Pesticides) [Category: Industry]

For triclopyr (USEPA/OPP Pesticide Code: 116001) 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./

Herbicide

Control of woody plants and many broad-leaved weeds (e.g. nettles, docks, brambles, gorse, broom) in grassland, uncultivated land, industrial areas, coniferous forests, plantation crops and rice fields.

Triclopyr is produced by reaction of 2,3,5,6-tetrachloropyridine with formaldehyde in dimethyl sulfoxide containing potassium cyanide, followed by hydrolysis of the cyano compound to the acid.

Preparation: L. D. Markley, United States of America patent 3862952 (1975 to Dow).

Prevamite (Nufarm America, Inc): Active ingredient: Dicamba 0.5465%; Triclopyr 0.7624%; Fenoxaprop-p-ethyl 0.5465%.

Trycera (Helena Chemical Company): Active ingredient: Triclopyr 29.4%.

Lesco Triclopyr 4 Ester Herbicide (Lesco, Inc): Active ingredient: Triclopyr 61.6%.

Gharda Triclopyr Acid Technical (Gharda Chemicals Limited): Active ingredient: Triclopyr 98.0%.

For more Formulations/Preparations (Complete) data for Triclopyr (25 total), please visit the HSDB record page.

Herbicides

Environmental transformation -> Pesticides (parent, predecessor)

Acetic acid, 2-[(3,5,6-trichloro-2-pyridinyl)oxy]-: ACTIVE

The WHO Recommended Classification of Pesticides by Hazard identifies Tryclopyr (technical grade) as Class II: moderately hazardous; Main Use: herbicide.

Over 70,000 pounds of triclopyr are used annually in the US.

Triclopyr is commercially available mainly as a triethylamine salt or butoxyethyl ester of the parent compound.