[4-14C]Estra-l,3,5(10)-triene-2,3, 17β-triol was injected iv into two female patients with T-tube drainage of the common bile duct, and bile and urine collected for 24 hr. Routine liver function tests were normal on the day of the study. [3H]2-Hydroxyestradiol-glutathione and [3H]2-hydroxyestrone-N-acetylcysteine were added to the bile and urine to act as carriers and recovery tracers. The bile and urine were analyzed by solvent extraction and repeated column chromatography. In the bile extracts, it was shown that no 14C label was associated with the [3H] estrogen-glutathione. Some 14C label remained in association with the [3H]estrogen-N-acetylcysteine but treatment with Ketodase or thinlayer chromatography separated the radioisotopes. It is concluded that in these subjects, in contrast to the rat, the synthesis of estrogen-glutathione conjugates from injected 2-hydroxyestradiol did not occur. Much of the excreted 14C label in both bile and urine was characterized as the 3-glucosiduronate of 2-methoxyestrone.