subchapter_subject: "ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS"
part_code: "556"
part_subject: "TOLERANCES FOR RESIDUES OF NEW ANIMAL DRUGS IN FOOD"
subpart_code: "B"
subpart_subject: "Specific Tolerances for Residues of New Animal Drugs"
section_number: "556.277"
section_subject: "Fenprostalene."
cfr_reference: "21 CFR 556.277"
title_name: "Title 21"
title_subject: "Food and Drugs"
parts_covered: "Parts 500 to 599"
revised_date: "Revised as of April 1, 2019"
publication_date: "As of April 1, 2019"
contains_description: "Containing a codification of documents of general applicability and future effect"
publication_info: "Published by the Office of the Federal Register National Archives and Records Administration as a Special Edition of the Federal Register"
---
A tolerance for marker residue of fenprostalene in cattle is not needed. The safe concentrations for the total residues of fenprostalene in the uncooked edible tissues of cattle are 10 parts per billion in muscle, 20 parts per billion in liver, 30 parts per billion in kidney, 40 parts per billion in fat, and 100 parts per billion in the injection site. As used in this section “tolerance” refers to a concentration of a marker residue in the target tissue selected to monitor for total residues of the drug in the target animal, and “safe concentrations” refer to the concentrations of total residues considered safe in edible tissues.