2,4,5-trichlorophenoxyacetic acid

herbicide

Also known as: 2,4,5-T

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Last updated

July 14, 2026

Quick Summary

2,4,5-trichlorophenoxyacetic acid, commonly known as 2,4,5-T, is a crystalline compound historically used as an herbicide and defoliant. It was developed in the late 1940s as part of a new era of chemical weed killers.12

A significant concern with 2,4,5-T is its association with dioxins, which are toxic by-products generated during its manufacture. The most notorious dioxin, 2,3,7,8-tetrachlorodibenzo-para-dioxin (2,3,7,8-TCDD), is a known human carcinogen and can cause various health issues. Due to these safety concerns, 2,4,5-T has been discontinued in many countries.32

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dioxin
Chemical characteristics and production
…Silvex (fenoprop) and 2,4,5-T (2,4,5-trichlorophenoxyacetic acid). The latter is a major active ingredient of Agent Orange, a defoliant formerly used in Vietnam by the U.S. military and in the United States to kill unwanted vegetation. This 2,4,5-trichlorophenol is used in the production of hexachlorophene, an antibacterial agent formerly used…
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…Silvex (fenoprop) and 2,4,5-T (2,4,5-trichlorophenoxyacetic acid). The latter is a major active ingredient of Agent Orange, a defoliant formerly used in Vietnam by the U.S. military and in the United States to kill unwanted vegetation. This 2,4,5-trichlorophenol is used in the production of hexachlorophene, an antibacterial agent formerly used…
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weed
Chemical control
…2,4-D (2,4-dichlorophenoxyacetic acid), 2,4,5-T (2,4,5-trichlorophenoxyacetic acid), and IPC (isopropyl-N-phenylcarbamate), the first two selective as foliar sprays against broad-leaved weeds, the third selective against grass species when applied through the soil. The new herbicides were revolutionary in that their high toxicity allowed for effective weed control at dosage rates as…
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…2,4-D (2,4-dichlorophenoxyacetic acid), 2,4,5-T (2,4,5-trichlorophenoxyacetic acid), and IPC (isopropyl-N-phenylcarbamate), the first two selective as foliar sprays against broad-leaved weeds, the third selective against grass species when applied through the soil. The new herbicides were revolutionary in that their high toxicity allowed for effective weed control at dosage rates as…
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chlorophenol
…grubs in cattle; and into 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) or 2,4,5-trichlorophenoxypropionic acid (2,4,5-TCPPA), both widely used as weed killers.
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…grubs in cattle; and into 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) or 2,4,5-trichlorophenoxypropionic acid (2,4,5-TCPPA), both widely used as weed killers.
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