BHT

Protects the formula.

What it is

Butylated hydroxytoluene, an antioxidant made in a lab.

An antioxidant that helps keep the oils in the product from going rancid.

A short summary from the dictionary, not yet an in-depth article. About these entries

Protects the formulaOfficial EU function: Antioxidant

Adds scentOfficial EU function: Fragrance

Restricted in certain uses · Cosmetics, EU

Allowed in EU cosmetics only within set limits and conditions (Annex III, entry 325).

A label gives no amounts, so none of this says a product is unsafe.