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CarCareTruth

Barium Sulfate

  • Thickeners
  • CAS 7727-43-7
  • IUPAC: Barium sulfate

Barium Sulfate (CAS 7727-43-7) appears in 1 of the 2,168 car-care products CarCareTruth tracks (as of August 2026).

Barium sulfate is one of the least soluble, least bioavailable barium compounds and carries no GHS hazard classification. Its extreme insolubility is the reason it is the barium compound used as an oral and rectal contrast medium in medical X-ray imaging, at doses far higher than any trace exposure from a metal polish. No SDS §2 hazard code applies to this ingredient specifically. Distinct from soluble barium salts (barium chloride, barium carbonate), which are genuinely toxic; solubility is what makes the difference.

Barium sulfate is a naturally occurring inorganic mineral salt (the mineral barite) used industrially as a dense, chemically inert filler and opacifying agent. In metal-polish creams it functions as a bulking agent that contributes to the paste's characteristic thick, creamy body rather than as an active cleaning or abrasive ingredient.

Its defining property is near-total insolubility in water and in body fluids, which is why medicine uses it as the contrast agent swallowed before an abdominal X-ray: the compound passes through the digestive tract essentially unabsorbed. That same insolubility is why the ecological and toxicological data are so mild compared with other barium compounds — soluble barium salts (barium chloride, barium carbonate) are genuinely hazardous, but barium sulfate's insolubility keeps it from being bioavailable in any meaningful way.

Health & environment profile

VOC
no
Prop 65 listed
no
Asthmagen
no
EPA Safer Choice
no
Aquatic toxicity
no
Biodegradable
no
Bioaccumulative
no
Persistent
yes
Ozone depleting
no
Microplastic
no
PFAS
no
Env. score
4/5
Purpose: Inert mineral filler and bulking agent that gives metal-polish cream its characteristic body and consistency

Common questions about Barium Sulfate

What is Barium Sulfate used for in car care?
Inert mineral filler and bulking agent that gives metal-polish cream its characteristic body and consistency
Is Barium Sulfate a VOC?
No. Barium Sulfate is not classified as a volatile organic compound (VOC).
Is Barium Sulfate on California's Proposition 65 list?
No. Barium Sulfate 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.