Zilpaterol.

(a) Acceptable daily intake (ADI). The ADI for total residue of zilpaterol is 0.083 µg/kg of body weight per day. (b) Tolerances. The tolerance for zilpaterol freebase (marker residue) is: (1) Cattle. (i) Liver (target tissue): 12 ppb. (ii) Muscle: 10 ppb. (2) [Reserved] (c) Related conditions of use. See § 558.665 of this chapter. [84 FR 32993, July 11, 2019, as amended at 85 FR 18121, Apr. 1, 2020]