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Sodium Borate (Borax)

  • Bases
  • CAS 1303-96-4
  • IUPAC: Disodium tetraborate decahydrate

Sodium Borate (Borax) (CAS 1303-96-4) appears in 3 of the 1,812 car-care products CarCareTruth tracks (as of June 2026).

Classified Repr. 1B (H360 — may damage fertility or the unborn child) at ingredient level; also H332 (harmful if inhaled) and H319 (eye irritation) at ingredient level. At <1% in the finished product mixture, these ingredient-level classifications do not trigger mixture-level classification per SDS §11 of products containing it. Used at low concentrations as a cleaning and pH-buffering agent.

Sodium borate (borax, CAS 1303-96-4) is an inorganic boron compound used as a cleaning agent, pH buffer, and water softener in cleaning formulations. It occurs naturally as a mineral deposit. At ingredient level it carries H360 (reproductive toxicant Cat 1B), H332 (harmful if inhaled), and H319 (eye irritation) classifications. These hazards are concentration-dependent and typically fall below mixture classification thresholds at <1% use concentrations in cleaning products. Not EPA Safer Choice listed. Not a Prop 65 chemical at this CAS number.

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
3/5
Purpose: Cleaning agent, pH buffer, and water softener in cleaning formulations

Common questions about Sodium Borate (Borax)

What is Sodium Borate (Borax) used for in car care?
Cleaning agent, pH buffer, and water softener in cleaning formulations
Is Sodium Borate (Borax) a VOC?
No. Sodium Borate (Borax) is not classified as a volatile organic compound (VOC).
Is Sodium Borate (Borax) on California's Proposition 65 list?
No. Sodium Borate (Borax) is not on California's Proposition 65 list.

3 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.