2,4,5-Trichlorophenoxyacetic acid (2,4,5-T)

Structure of 2,4,5-T

CAS Number: 93-76-5

2,4,5‐T was used in the past to control weeds in forests, parks, pastures, lawns, and along roadsides and railroad tracks. Because of toxicity concerns, most uses were ended in the U.S. in the 1970s. All uses of 2,4,5‐T in the U.S. ended by 1985. Biomonitoring California tests for 2,4,5‐T only because it is included in a laboratory method that measures a group of similar chemicals. We do not expect to find 2,4,5‐T in people’s urine.

2,4,5-Trichlorophenoxyacetic acid (2,4,5-T) is part of the group of Herbicides. Click here to learn more about this group of chemicals.

Fact Sheet

2,4,5-T was found in

Weed control products used in the past in forests, parks, pastures, lawns and along roadsides and railroad tracks. All uses of 2,4,5‐T in the U.S. ended by 1985.

Possible health concerns of 2,4,5-T

Weed control products that contained 2,4,5‐T were contaminated with dioxin, a toxic chemical known to cause cancer and harm the developing fetus. Use of these weed
control products ended because of toxicity concerns, but it is not known whether 2,4,5‐T itself posed health concerns or if toxicity was due to dioxin alone.