What is Butylated hydroxytoluene – BHT (E321)?
Last updated on: 12/21/2025
Sources: WHO, US-FDA, EFSA, FSSAI.
6
/10
Moderate Concern
Generally safe within limits, intake monitoring is advised for children.
CTL SAFETY SCORE
A higher score reflects higher confidence in safety; it is based on regulatory approvals, intake limits, and individual sensitivities data.
Butylated hydroxytoluene (BHT) is a synthetic antioxidant used to prevent fats and oils from oxidative degradation. It is typically used in fat-rich and processed foods, where oxidation would otherwise reduce the quality and stability of the products.
Safety Summary
- Approved by all major regulatory bodies under specified limits.
- WHO / JECFA established an ADI of 0–0.3 mg/kg body weight/day, based on long-term toxicological studies.
- EFSA confirmed the same average daily intake (ADI) and concluded that BHT does not raise a safety concern at authorized use levels for the general population.
- EFSA exposure assessments showed that high consumers, particularly children, may reach or slightly exceed the ADI in certain dietary scenarios.
- Sensitivity group involves children with high exposure to BHT products; individuals exposed occupationally (inhalation/skin contact), and species with insufficient tolerance data
Who should be cautious?
Children at high exposure percentiles; individuals exposed occupationally (inhalation/skin contact); species with insufficient tolerance data
Quick Facts
|
E-Number : |
E321 |
|
INS Number : |
INS-321 |
|
Category : |
Preservative |
|
Sub-category : |
Antioxidant |
|
Origin : |
Synthetic (Chemically derived) |
|
Used In : |
Food |
|
Alternative Names : |
321, BHT |
|
Similar Ingredients : |
Butylated hydroxyanisole (BHA, E320); TBHQ (E319); Ethoxyquin (E324) |
Common Products
You may find this in the following food products:
- Vegetable oils and fats,
- Ghee,
- Lard, tallow, fish oil,
- Fat spread,
- Snacks – potato,
- Cereal,
- Flour or starch based Ready-to-eat savouries etc.
Regulatory Approval.
1. Food and drug administration (fDA – USA)
Status |
Usage Limit |
|---|---|
|
Approved (with restrictions) |
Limit varies by food category (total BHA and BHT) eg. Dry breakfast cereals 50ppm, Potato flakes 50 ppm etc. |
2. European Food Safety authority (eFSA)
Status |
Usage Limit |
|---|---|
|
Approved |
Group Average Daily intake(ADI): 0.25 mg/kg body weight per day, feed use considered safe up to 150 mg/kg complete feed for certain species (e.g., chickens, pigs) |
3. Food safety and standardization authority India (FSSAI)
Status |
Usage Limit |
|---|---|
|
Approved |
Maximum permitted levels vary by food category, eg. Fine Bakery ware 200 mg/kg, Chewing gum 400 mg/kg, pre-cooked pastas and noodles 200 mg/kg etc. |
Health concerns
- EFSA and WHO/JECFA, both regulatory bodies, identify dietary exposure level as the key risk factor rather than inherent toxicity in BHT.
- EFSA observed liver and thyroid effects in animal studies at doses well above human dietary exposure, while mild gastrointestinal or metabolic effects are reported in humans in some experimental settings.
- EFSA highlighted that children with high intake of foods containing BHT may approach or exceed the ADI, making them the most sensitive group from a dietary exposure perspective.
- Population with high consumption of processed and fat-rich foods may have higher cumulative exposure.
- No specific risks were identified for pregnant women or the general adult population when intake remains within the ADI.
- EFSA did not identify acute toxicity concerns but emphasized the importance of maintaining exposure below the ADI, especially for children.
Conclusions
Butylated hydroxytoluene BHT (E321) is an effective antioxidant with long-standing regulatory approval. While it is considered safe within established ADIs, EFSA highlights that children and high consumers of processed foods may approach or exceed safe intake levels. For this reason, BHT is best consumed in moderation, requiring controlled use according to studies.