Namely
BHT or Butylhydroxytoluene is a phenol which is in the form of yellowish-white crystals. It is used for its antioxidant properties in cosmetics.
IARC (International Center for Research on Cancer) classifies BHT among substances whose safety could not be established, the ARTAC (French Association for Therapeutic Anti-Cancer Research), class it, among the substances "probably carcinogenic".
The substance is suspected to be an endocrine disruptor that can destabilize reproductive hormones in men and women. The molecule is also known as sensitizing, which can be a source of allergies.
As far as it is possible in cosmetics to do otherwise, according to the precautionary principle, we classify this molecule in red on INCI Beauty.