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2,4,6-Tri-tert-butylphenol

  • Antioxidants
  • CAS 732-26-3
  • IUPAC: 2,4,6-tri-tert-butylphenol

2,4,6-Tri-tert-butylphenol (CAS 732-26-3) appears in 1 of the 1,812 car-care products CarCareTruth tracks (as of June 2026).

H301 (toxic if swallowed Acute Tox Cat 3), H317 (skin sensitizer Cat 1B), H372 (STOT RE Cat 1 — causes damage to organs through prolonged or repeated exposure) at the substance level. Despite the severe substance-level classifications, at <1% in a diesel treatment formulation, these hazards typically do not propagate to the mixture-level SDS classification. The skin sensitizer (H317) classification means products containing this ingredient may produce allergic reactions in sensitized individuals upon repeated skin contact.

2,4,6-Tri-tert-butylphenol (CAS 732-26-3) is a hindered phenol antioxidant used at trace concentrations (<1%) in fuel additive formulations. Despite its benign-sounding function, it carries significant substance-level hazard classifications: H301 (toxic if swallowed, Acute Tox Cat 3), H317 (skin sensitizer Cat 1B), and H372 (STOT RE Cat 1 — causes damage to organs through prolonged or repeated exposure). At <1% in a diesel treatment formulation, these classifications typically do not propagate to the mixture-level SDS classification per GHS concentration cutoffs, but the SDS §2 precautionary statement may still note: "Contains 2,4,6-tri-tert-butylphenol. May produce an allergic reaction."

Health & environment profile

VOC
no
Prop 65 listed
no
Asthmagen
no
EPA Safer Choice
no
Aquatic toxicity
no
Biodegradable
no
Bioaccumulative
no
Persistent
no
Ozone depleting
no
Microplastic
no
PFAS
no
Env. score
4/5
Purpose: Hindered phenol antioxidant used as a stabilizer in fuel additive and lubricant formulations.

Common questions about 2,4,6-Tri-tert-butylphenol

What is 2,4,6-Tri-tert-butylphenol used for in car care?
Hindered phenol antioxidant used as a stabilizer in fuel additive and lubricant formulations.
Is 2,4,6-Tri-tert-butylphenol a VOC?
No. 2,4,6-Tri-tert-butylphenol is not classified as a volatile organic compound (VOC).
Is 2,4,6-Tri-tert-butylphenol on California's Proposition 65 list?
No. 2,4,6-Tri-tert-butylphenol is not on California's Proposition 65 list.

1 product contain this

Related

Health and environment notes translate the manufacturer Safety Data Sheet, the GHS classification, and authoritative regulatory listings (California Prop 65, EPA). Not medical advice. They describe the ingredient itself; whether a hazard applies to a finished product depends on its concentration and how it's used.