{"topic_id":"vet_drug_mrl_us_cfr556","category":"vet-drug-mrl","context":"---\ntopic_id: vet_drug_mrl_us_cfr556\ncategory: vet-drug-mrl\ntitle: \"US 21 CFR Part 556 — tolerances for new animal drugs in food-producing animals\"\nlang: en\nsource: \"US eCFR 21 CFR Part 556 (landed pdf-raw/vet-drug-mrl/us_cfr_556.xml / .html)\"\nsource_file: pdf-raw/vet-drug-mrl/us_cfr_556.xml\ndate_parsed: 2026-08-09\ntokens_estimated: 220\nverified: true\nverification: c1_substring\nsource_document: \"21 CFR Part 556 — Tolerances for residues of new animal drugs in food\"\ncitation:\n  authority: \"U.S. FDA / U.S. Government Publishing Office (eCFR)\"\n  title: \"21 CFR Part 556 — Tolerances for residues of new animal drugs in food\"\n  url: \"https://www.ecfr.gov/current/title-21/chapter-I/subchapter-E/part-556\"\n  retrieved: \"2026-08-09\"\n  ref: \"21 CFR 556\"\n  doc_type: \"official web page\"\n  needs_review: false\nlicense: public_domain\n---\n\nIn the United States, residue limits for veterinary (new animal) drugs in food are set as tolerances under 21 CFR Part 556. Per § 556.1 Scope, the Federal Food, Drug, and Cosmetic Act requires an applicant seeking approval or conditional approval of a new animal drug to submit a proposed tolerance as part of its new animal drug application when such a tolerance is needed to assure that the proposed use of the new animal drug is safe.\n\nEach substance sub-section in Part 556 (e.g., § 556.xxx) lists the commodity (target food-producing animal tissue), the tolerance (in ppm / µg/g), and the relevant § 500.4(d) regulatory status. This is the US analogue to the EU 2377/90 MRL framework and China GB 31650.\n\nScope note: 21 CFR 556 targets food-producing animals; companion-animal pet food relevance is indirect (animal-derived ingredient residue controls).\n\nSource: `pdf-raw/vet-drug-mrl/us_cfr_556.xml` (eCFR 21 CFR Part 556, first-hand).\n\n## Claims (verified C1 substrings of source_file)\n- `§ 556.1 Scope.`\n- `The Federal Food, Drug, and Cosmetic Act requires an applicant seeking approval or conditional approval of a new animal drug`\n- `submit a proposed tolerance as part of its new animal drug application when such a tolerance is needed to assure that the proposed use of the new animal drug`\n","sources":["EU Regulation — 21 CFR Part 556 — Tolerances for residues of new animal drugs in food (retrieved 2026-08-09)"],"source":{"authority":"EU Regulation","title":"21 CFR Part 556 — Tolerances for residues of new animal drugs in food","url":"https://www.ecfr.gov/current/title-21/chapter-I/subchapter-E/part-556","retrieved":"2026-08-09","ref":"","doc_type":"official PDF","source_document":"21 CFR Part 556 — Tolerances for residues of new animal drugs in food","verification_file":"pdf-raw/vet-drug-mrl/us_cfr_556.xml"},"source_document":"21 CFR Part 556 — Tolerances for residues of new animal drugs in food","source_file":"pdf-raw/vet-drug-mrl/us_cfr_556.xml","trust":{"authority_tier":"ungraded","fidelity":"verbatim","license":"public_domain","display_grade":"pending"},"tokens_estimated":220,"generated_at":null,"tip":"Use /api/v1/topics to discover more topics. /api/v1/nutrient for precise single-point queries. /api/v1/cross_compare for 2-3 standard comparisons."}