2,4,5-Trichlorophenol (TCP) is an organochloride with the molecular formula C6H3Cl3O.

It has been used as a fungicide and herbicide.

[2] Precursor chemical used in the production of 2,4,5-Trichlorophenoxyacetic acid (2,4,5-T) and hexachlorophene involves the intermediate production of 2,4,5-trichlorophenol (TCP) and the formation of 2,3,7,8-Tetrachlorodibenzodioxin (TCDD, commonly referred to simply as dioxin) as an unwanted by-product.

In the course of purifying the hexachlorophene, still bottom wastes were created with concentrated levels of TCP and dioxin.