Skip to content
CarCareTruth

tert-Butylbenzene

  • Aromatic solvents
  • CAS 98-06-6
  • IUPAC: (2-Methylpropan-2-yl)benzene

tert-Butylbenzene (CAS 98-06-6) appears in 2 of the 2,122 car-care products CarCareTruth tracks (as of August 2026). It is classified as a VOC.

Aromatic alkyl-benzene with narcotic effect on inhalation (contributes to mixture-level H336). No specific carcinogenicity classification, but on the California Candidate Chemicals List. Skin and eye irritant at high concentration. Vapor pressure makes inhalation the primary exposure route during aerosol application.

tert-Butylbenzene (CAS 98-06-6) is a single-ring aromatic hydrocarbon — a benzene ring with a branched four-carbon substituent — present at 1–3% in heavy-aromatic-naphtha solvent cuts. It is an identified constituent of the C9–C15 heavy aromatic hydrocarbons fraction (CAS 64742-94-5) and is broken out separately on the SDS because it appears on California's Safer Consumer Products Candidate Chemicals List.

The bioaccumulation potential (log Kow 4.11) and persistence place it in the "of-concern" tier for aquatic and soil environments. As a VOC it contributes to ground-level ozone formation. At 1–3% in a consumer aerosol it is not the dominant health driver, but it stacks with naphthalene, the heavy-aromatic fraction, and the petroleum distillate to push the mixture into multiple GHS classifications simultaneously.

For users: a marker ingredient indicating the product is a true solvent-naphtha-based formula rather than a milder modified-petroleum cleaner. Not a single-ingredient action item by itself.

Health & environment profile

VOC
yes
Prop 65 listed
no
Asthmagen
no
EPA Safer Choice
no
Aquatic toxicity
yes
Biodegradable
no
Bioaccumulative
yes
Persistent
yes
Ozone depleting
no
Microplastic
no
PFAS
no
Env. score
2/5
Purpose: Aromatic-solvent component within the heavy-aromatic-hydrocarbons fraction of petroleum-based degreasers. Contributes to penetration of polar grease residues.

Common questions about tert-Butylbenzene

What is tert-Butylbenzene used for in car care?
Aromatic-solvent component within the heavy-aromatic-hydrocarbons fraction of petroleum-based degreasers. Contributes to penetration of polar grease residues.
Is tert-Butylbenzene a VOC?
Yes. tert-Butylbenzene is classified as a volatile organic compound (VOC).
Is tert-Butylbenzene on California's Proposition 65 list?
No. tert-Butylbenzene is not on California's Proposition 65 list.

2 products 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.