Butylated Hydroxyanisole E320
synthetic — Primarily synthetic.
tert-Butyl-4-methoxyphenol
CAS: 25013-16-5
Factual Regulatory Reference
This database provides factual regulatory information compiled from official government sources. It does not constitute medical, nutritional, or safety advice. Regulatory status varies by country and is subject to change. Always refer to your local regulatory authority for the most current information.
What Is Butylated Hydroxyanisole?
Butylated hydroxyanisole (BHA, E320) is a synthetic phenolic antioxidant manufactured by alkylating 4-methoxyphenol with isobutylene in the presence of an acid catalyst; it prevents oxidative rancidity in fats and oils and has no natural equivalent. It is found in butter, margarine, vegetable oils, snack foods, breakfast cereals, chewing gum, and dehydrated foods, and is also used in cosmetics, pharmaceuticals, and petroleum products. BHA is approved by the FDA (GRAS, 21 CFR 172.110), EFSA, JECFA (ADI of 0.5 mg/kg body weight per day, 2020), Health Canada, and FSANZ, but is classified as a Group 2B possible carcinogen by IARC and is listed as 'reasonably anticipated to be a human carcinogen' by the US National Toxicology Program, based on forestomach tumor findings in rodents — a species-specific endpoint that has led to scientific disagreement about the relevance of the animal data to human risk.
? Did You Know?
Beyond food, Butylated Hydroxyanisole is also used in cosmetics, medicine, industrial applications, household products. Its versatility makes it one of the most multi-purpose chemical compounds in everyday life.
Regulatory Analysis
BHA presents a textbook case of regulatory fragmentation: IARC classifies it as a Group 2B possible carcinogen, the US National Toxicology Program lists it as 'reasonably anticipated to be a human carcinogen,' and California requires cancer warnings on products containing it, yet the FDA maintains its GRAS status and EFSA keeps it approved with an ADI of 0.5 mg/kg. The animal evidence shows BHA causes forestomach tumors in rodents, but humans lack a forestomach, creating a species-specificity argument that divides toxicologists on whether the finding is relevant to human risk. This anatomical extrapolation debate makes BHA a touchstone case for how structural differences between test animals and humans should influence regulatory weight-of-evidence determinations.
Detailed Regulatory Assessment
European Union (EFSA)
Restricted use; maximum levels typically 100-200 mg/kg
United States (FDA)
Limited to specified levels in specific foods
Japan (MHLW)
Compliant with Japanese food sanitation law.
Acceptable Daily Intake (ADI)
International Standard (JECFA)
mg/kg body weight per day
European Standard (EFSA)
Natural Occurrence
This additive is not known to occur naturally in significant quantities.
Manufacturing
Synthesized by alkylation of 4-methoxyphenol (p-anisole) with isobutylene in the presence of an acid catalyst.
Applications Beyond Food
Used in lipsticks and moisturizers as an antioxidant.
Used in pharmaceutical preparations to prevent oxidation.
Used in petroleum products, rubber, and plastics as a stabilizer.
Found in some food packaging materials
Safety & Regulatory History
Full Timeline →FDA approved BHA (butylated hydroxyanisole) as antioxidant for food preservation.
Japanese studies found BHA caused tumors in forestomach of rats at high doses, raising safety con...
IARC classified BHA as 'possibly carcinogenic to humans' (Group 2B) based on animal studies.
JECFA concluded forestomach tumors in rats are not relevant to humans (humans lack forestomach). ...
FDA reviewed BHA safety following IARC classification, concluded available evidence supports cont...
EFSA re-evaluated BHA (E320), concluded ADI of 0.5 mg/kg bw/day is protective and BHA is safe at ...
California added BHA to Proposition 65 list of chemicals known to cause cancer, requiring warning...
FDA approved BHA (butylated hydroxyanisole) as antioxidant for food preservation.
Japanese studies found BHA caused tumors in forestomach of rats at high doses, raising safety concerns.
IARC classified BHA as 'possibly carcinogenic to humans' (Group 2B) based on animal studies.
JECFA concluded forestomach tumors in rats are not relevant to humans (humans lack forestomach). Maintained ADI of 0-0.5 mg/kg bw/day.
FDA reviewed BHA safety following IARC classification, concluded available evidence supports continued safe use within regulated limits.
EFSA re-evaluated BHA (E320), concluded ADI of 0.5 mg/kg bw/day is protective and BHA is safe at current use levels.
California added BHA to Proposition 65 list of chemicals known to cause cancer, requiring warning labels on products sold in California.