Benzene
- Aromatic solvents
- CAS 71-43-2
- IUPAC: Benzene
Benzene (CAS 71-43-2) appears in 2 of the 1,812 car-care products CarCareTruth tracks (as of June 2026), 2 of which carry a DANGER signal word on their published Safety Data Sheet. It is listed on California's Proposition 65 and classified as a VOC.
IARC Group 1 (confirmed human carcinogen) — leukemia and other blood cancers with occupational inhalation exposure. California Prop 65 listed: known carcinogen (leukemia), male reproductive toxin, and developmental toxin. ACGIH TLV 0.5 ppm (8-hr TWA), STEL 2.5 ppm — very low permissible level. At <0.02% in undercoating formula, benzene is a trace impurity from the petroleum solvent fraction, not an intentional ingredient. OSHA 29 CFR 1910.1028 applies to occupational exposures ≥0.1% benzene.
Benzene (CAS 71-43-2) is an IARC Group 1 confirmed human carcinogen found at trace levels (<0.02%) as an impurity in petroleum-derived solvents, naphtha fractions, and toluene. In rubberized undercoating formulas, benzene is not intentionally added — it is a residual impurity from the petroleum refining process. The US EPA assigns the D018 hazardous waste code to wastes containing ≥0.5 mg/L benzene. Despite its trace concentration in the finished product, its California Prop 65 listing (carcinogen, male reproductive toxin, developmental toxin) requires disclosure on product labels when present above the No Significant Risk Level.
Health & environment profile
- VOC
- yes
- Prop 65 listed
- yes
- Asthmagen
- no
- EPA Safer Choice
- no
- Aquatic toxicity
- yes
- Biodegradable
- yes
- Bioaccumulative
- no
- Persistent
- no
- Ozone depleting
- no
- Microplastic
- no
- PFAS
- no
- Env. score
- 2/5
Common questions about Benzene
- What is Benzene used for in car care?
- Trace contaminant found at very low levels (<0.02%) in petroleum-derived solvents and naphtha fractions; not intentionally added
- Is Benzene a VOC?
- Yes. Benzene is classified as a volatile organic compound (VOC).
- Is Benzene on California's Proposition 65 list?
- Yes. Benzene appears on California's Proposition 65 list.
- Is Benzene biodegradable?
- Yes. Benzene has a confirmed biodegradable profile.
2 products contain this
Prop 65
Hot Shot's Secret Gasoline Extreme (GE16Z)Prop 65fuel-system-cleaner
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.