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CarCareTruthProducts · Ranked

Iron Oxide

  • Dyes & colorants
  • CAS 1309-37-1
  • IUPAC: Iron(III) oxide

Iron Oxide (CAS 1309-37-1) appears in 1 of the 1,812 car-care products CarCareTruth tracks (as of June 2026).

Iron oxide at concentrations used in consumer paints and putties is not classified as a GHS health hazard. Not Prop 65–listed for the inorganic form. IARC classifies certain iron oxide dusts as Group 1 (lung cancer in occupational iron/steel foundry exposure at very high dust concentrations) — this classification does not apply to consumer-product use of iron oxide as a pigment in a liquid matrix where no respirable dust exposure occurs.

Iron oxide (Fe₂O₃, ferric oxide) is a naturally occurring inorganic pigment responsible for the distinctive red-brown color of Bondo glazing putties and many automotive primers. It is chemically inert, non-toxic at consumer product concentrations, and not classified as a GHS health or environmental hazard in liquid coatings formulations. The compound provides excellent UV stability and is one of the most durable inorganic pigments used in coatings.

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: Inorganic red pigment in paints and putties; provides characteristic red-brown color to Bondo-type glazing putties

Common questions about Iron Oxide

What is Iron Oxide used for in car care?
Inorganic red pigment in paints and putties; provides characteristic red-brown color to Bondo-type glazing putties
Is Iron Oxide a VOC?
No. Iron Oxide is not classified as a volatile organic compound (VOC).
Is Iron Oxide on California's Proposition 65 list?
No. Iron Oxide 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.