[(3,5,6-trichloro-2-pyridyl)oxy]acetic acid, compound with triethylamine (1:1)

Description

Triclopyr triethylamine salt was first reported in 1975 by Byrd and coworkers. Triclopyr, also known by the trade name Garlon, is an herbicide used extensively in the control of woody plants and broadleaf weeds.

Uses

Triclopyr is an herbicide used to control woody plants and many broadleaf weeds including rights-of-way, industrial areas, forestry, railways, rangeland, home lawns, and permanent grass pastures, rice, turf, and plantation crops such as palm oil. Triclopyr triethylamine salt is a selective systemic herbicide that is rapidly absorbed by the green bark, leaves, and roots and distributed throughout the plant. Triclopyr accumulates in the meristematic tissue (growth region) of the plant. Triclopyr is formulated as triclopyr triethylamine (TEA) salt or triclopyr butoxyethyl ester. Triclopyr is formulated as soluble and emulsifiable concentrates, powders, pellets, granules, and liquids.

Uses

Herbicide.

General Description

Colorless to amber liquid.

Air & Water Reactions

Water soluble.

Reactivity Profile

[(3,5,6-trichloro-2-pyridyl)oxy]acetic acid, compound with triethylamine (1:1) is incompatible with strong oxidizers.

Agricultural Uses

Herbicide: A systemic herbicide used on rice, range land and pasture, rights-of-way, forestry and grasslands, including home lawns, for control of broadleaf weeds and woody plant. Registered for use in EU countries . Registered for use in the U.S.

Trade name

BRUSH-B-GON®; CONFRONT®; CROSSBOW®; DOWELANCO® BRUSH AND WEED; DTDA/DMA-TEA-DMA® SELECTIVE HERBICIDE; GARLON-3A®; GRANDSTAND®; MON® 78736; REDEEM® R & P; RENOVATE®; RIVERDALE DTDA® SELECTIVE HERBICIDE; RIVERDALE HORSEPOWER®; TRICLOPRY-EZ-JECT®; TURFLON® AMINE; XRM-5202®; WEEDEX®

Environmental Fate

Triclopyr TEA is a grayish white granular solid. It is miscible in water, slightly soluble in toluene and ethyl acetate, and practically insoluble in hexane. The Henry’s law constant is 1.15 × 10^-14 atm-m3 mol^-1; octanol/water partition coefficient is <5 (1.23).
Air
Volatilization of triclopyr TEA occurs slightly due to its lower vapor pressure. Low Henry’s law constant indicates little escaping tendency from an aqueous solution. Triclopyr is not found in air with the exception of spray drift and dust from pesticide application.
Water
Triclopyr TEA is degraded by photodegradation in water. It is highly water soluble and dissociates to the weak acid triclopyr acid and triethanolamine. Triethanolamine rapidly degrades to CO2 by aerobic microbial processes (half-life 14–18 days). However, triethanolamine does not degrade under anaerobic aquatic conditions (half-life >2 years). Triclopyr acid further dissociates to triclopyr anion, which is the predominant moiety in the environment. The photolysis of triclopyr acid in aqueous media is rapid and the half-life is approximately 1 day in water. The major photolyzed products of triclopyr acid observed were 5-chloro-3,6-dihydroxy-2-pyridinoloxyacetic acid and oxamic acid in water.
Soil
The major route of dissipation in soil is through microbial degradation. Moisture favors the microbial growth, which in turn increases microbial activity. The triclopyr acid is degraded primarily by microbes with half-lives of 8–18 days to intermediate compounds 3,5,6-trichloro-2-pyridinol (TCP) and 3,5,6-trichloro-2-methoxypyridine (TMP), and CO2. Triclopyr, TMP, and TCP have lower soil mobility due to which there might be limited leaching.
There is no evidence on bioaccumulation of triclopyr in fish or aquatic nontarget microorganisms.

Toxicity evaluation

The mechanism of action of triclopyr in mammals is still unclear, although its mechanism of toxicity in plants is well documented. The triclopyr exerts its toxicity in plants by mimicking the effect of plant growth hormones, which is similar to its pyridine analog 2,4,5-trichlorophenoxy acetic acid. Histopathology and clinical chemistry laboratory data suggest that the liver and kidneys are the primary target organs. Like any chemical, triclopyr can cause lethality at very high doses. Triclopyr is excreted primarily through kidneys by a welldefined active transport process. This process may become impeded and saturated at very high doses.