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CarCareTruthProducts · Ranked

Diethanolamine (DEA)

  • Bases
  • CAS 111-42-2
  • IUPAC: 2,2'-iminobis(ethanol)

Diethanolamine (DEA) (CAS 111-42-2) appears in 5 of the 1,812 car-care products CarCareTruth tracks (as of June 2026). It is listed on California's Proposition 65.

Mild skin and eye irritant at concentrate. No H-codes at typical product concentrations. DEA has some historical concern around nitrosamine formation in cosmetics when combined with nitrosating agents, but this is not a standard concern in automotive formulations.

Diethanolamine is an alkanolamine used as a pH buffer, emulsifier, and foam stabilizer in wax and liquid polish formulations. It adjusts the pH of the formulation and helps stabilize emulsions between water and oil/solvent phases.

At 0.1–2% in automotive waxes and glazes, it contributes minimal health or environmental risk. The historical nitrosamine concern (relevant in cosmetics with nitrosating agents) is not a standard issue in auto-care applications.

In alkaline heavy-duty cleaners and engine degreasers (e.g., Simple Green Pro HD), DEA appears at much lower concentrations — typically <0.01% as a trace pH co-buffer alongside primary alkaline builders. At that level the chemistry contribution is negligible, but DEA's presence on the California Proposition 65 carcinogen list still requires a Prop 65 warning on the product label regardless of concentration.

Health & environment profile

VOC
no
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
3/5
Purpose: pH buffer, emulsifier, and foam stabilizer in wax and polish formulations; trace pH co-buffer in alkaline cleaners and engine degreasers

Common questions about Diethanolamine (DEA)

What is Diethanolamine (DEA) used for in car care?
pH buffer, emulsifier, and foam stabilizer in wax and polish formulations; trace pH co-buffer in alkaline cleaners and engine degreasers
Is Diethanolamine (DEA) a VOC?
No. Diethanolamine (DEA) is not classified as a volatile organic compound (VOC).
Is Diethanolamine (DEA) on California's Proposition 65 list?
Yes. Diethanolamine (DEA) appears on California's Proposition 65 list.
Is Diethanolamine (DEA) biodegradable?
Yes. Diethanolamine (DEA) has a confirmed biodegradable profile.

5 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.