BHT
Butylated hydroxytoluene (BHT)
- Role
- Protects the oils and fragrance in a formula from oxidation.
- Catalog formulas
- 15
- Type
- Stability
- Verified
- 06.11.2026
What does this ingredient do in an antiperspirant?
As an antioxidant, it slows reactions with oxygen that make oils and fragrance ingredients go rancid or change their smell or color.
Part of a system, not a label in isolation
In antiperspirants it usually sits near the end of the list: oil-based sticks and fragranced aerosols need only a little of it. Its job is to keep the product stable, not to care for the skin.
Since 2023, BHT has been restricted in the EU under Annex III of Regulation 1223/2009: up to 0.8% in leave-on and rinse-off products (lower limits apply to mouthwash and toothpaste). The CIR found BHT safe at the low concentrations used in cosmetics.
According to the CIR, limited skin studies and clinical reports showed no significant irritation, sensitization or photosensitization.
It is not the same as BHA (butylated hydroxyanisole), a different antioxidant with its own assessment. Nor is it a preservative: other ingredients protect against microbes.
Products containing BHT
Links are based on the complete published INCI list for the exact product version.
Sources
The conclusions apply to the stated conditions and jurisdictions, not automatically to every concentration or product.
- Regulation (EU) 2022/2195: BHT in Annex III Supports: permitted concentration, restrictions
- CIR: Final report on the safety assessment of BHT (2002) Supports: safety assessment, irritation and sensitisation
- COSMILE Europe (CosIng data): BHT Supports: function