Home › CFR › Title 21 › Part 17121 CFR Part 171 — Food Additive PetitionsSubpart A — General Provisions§ 171.1— Petitions.§ 171.6— Amendment of petition.§ 171.7— Withdrawal of petition without prejudice.§ 171.8— Threshold of regulation for substances used in food-contact articles.Subpart B — Administrative Actions on Applications§ 171.100— Regulation based on petition.§ 171.102— Effective date of regulation.§ 171.110— Procedure for objections and hearings.§ 171.130— Procedure for amending and repealing tolerances or exemptions from tolerances.