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Molybdenum Disulfide

  • Other
  • CAS 1317-33-5
  • IUPAC: molybdenum(IV) sulfide

Molybdenum Disulfide (CAS 1317-33-5) appears in 1 of the 1,812 car-care products CarCareTruth tracks (as of June 2026).

Molybdenum disulfide (MoS2) is not classified as a sensitizer, carcinogen, or reproductive toxicant under OSHA HCS at ingredient level. ACGIH TLV exposure limits apply for dust/powder handling. In paste format bound in a grease carrier, inhalation pathway is not present during normal application.

Molybdenum disulfide (MoS2) is a black solid mineral used as an extreme-pressure lubricant additive in anti-seize compounds, dry film lubricants, and greases. In Never-Seez Blue Moly and similar nickel/moly anti-seize products, MoS2 contributes extreme-pressure film strength alongside the nickel metal flake, making the combination suitable for high-load, slow-moving threaded assemblies and stainless steel fastener applications.

MoS2 has a layered crystal structure that allows the layers to slide easily under pressure, providing low-friction protection even when the grease carrier has burned off under heat cycling. It is thermally stable to approximately 350°C in air (higher in inert or reducing atmospheres).

heavy_metal_containing: true — contains molybdenum (heavy metal, though of low toxicological concern in MoS2 form).

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: Extreme-pressure lubricant additive (MoS2); provides lubrication in high-load, high-temperature fastener and anti-seize applications

Common questions about Molybdenum Disulfide

What is Molybdenum Disulfide used for in car care?
Extreme-pressure lubricant additive (MoS2); provides lubrication in high-load, high-temperature fastener and anti-seize applications
Is Molybdenum Disulfide a VOC?
No. Molybdenum Disulfide is not classified as a volatile organic compound (VOC).
Is Molybdenum Disulfide on California's Proposition 65 list?
No. Molybdenum Disulfide 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.