21 CFR § 172.185 - Tbhq.

---
identifier: "/us/cfr/t21/s172.185"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "21 CFR § 172.185 - TBHQ."
title_number: 21
title_name: "Food and Drugs"
section_number: "172.185"
section_name: "TBHQ."
chapter_name: "FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES"
subchapter_number: "B"
subchapter_name: "FOOD FOR HUMAN CONSUMPTION"
part_number: "172"
part_name: "FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION"
positive_law: false
currency: "2026-04-05"
last_updated: "2026-04-05"
format_version: "1.1.0"
generator: "[email protected]"
authority: "21 U.S.C. 321, 341, 342, 348, 371, 379e."
regulatory_source: "42 FR 14491, Mar. 15, 1977, unless otherwise noted."
cfr_part: "172"
---


# 172.185 TBHQ.

The food additive TBHQ, which is the chemical 2-(1,1-dimethylethyl)-1,4-benzenediol (Chemical Abstracts Service Registry Number 1948-33-0), also known as tertiary butylhydroquinone, may be safely used in food in accordance with the following prescribed conditions:

(a) The food additive has a melting point of not less than 126.5 °C.

(b) The percentage of TBHQ in the food additive is not less than 99.0 percent when tested by the assay described in the Food Chemicals Codex, 9th ed. (2014), pp. 1192-1194, which is incorporated by reference, or an equivalent method. The Director of the Office of the Federal Register approves this incorporation by reference in accordance with 5 U.S.C. 552(a) and 1 CFR part 51. You may obtain copies from the United States Pharmacopeial Convention, 12601 Twinbrook Pkwy., Rockville, MD 20852 (Internet address: *http://www.usp.org*). Copies may be examined at the Dockets Management Staff (HFA-305), Food and Drug Administration, 5630 Fishers Lane, Rm. 1061, Rockville, MD 20852, 240-402-7500, between 9 a.m. and 4 p.m., Monday through Friday, or at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call 202-741-6030 or go to: *http://www.archives.gov/federal-register/cfr/ibr-locations.html*.

(c) It is used as an antioxidant alone or in combination with BHA and/or BHT.

(d) The total antioxidant content of a food containing the additive will not exceed 0.02 percent of the oil or fat content of the food, including the essential (volatile) oil content of the food.

[42 FR 14491, Mar. 15, 1977, as amended at 80 FR 34276, June 16, 2015; 88 FR 17719, Mar. 24, 2023]