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CarCareTruthProducts · Ranked

Dibutyl Phthalate

  • Esters
  • CAS 84-74-2
  • IUPAC: Dibutyl benzene-1,2-dicarboxylate

Dibutyl Phthalate (CAS 84-74-2) appears in 1 of the 1,812 car-care products CarCareTruth tracks (as of June 2026), 1 of which carry a DANGER signal word on their published Safety Data Sheet. It is listed on California's Proposition 65.

California Prop 65–listed reproductive toxin. EU-designated endocrine disruptor (SVHC under REACH). GHS classification includes suspected reproductive toxicity. At trace concentrations (<3%) in a solvent-borne putty used by home users, direct exposure is limited, but the Prop 65 listing requires label disclosure. The reproductive toxicity classification (Category 2 suspected) contributes to the product's Prop 65 warning.

Dibutyl phthalate (DBP) is a phthalate ester plasticizer historically used in nitrocellulose lacquers and putties to maintain flexibility in the cured film and prevent cracking. It is listed under California Proposition 65 as a reproductive toxin and is designated as a Substance of Very High Concern (SVHC) under the EU REACH regulation due to its endocrine-disrupting properties. DBP is classified as aquatically toxic (H411) and bioaccumulates in aquatic organisms. In consumer polyester putty formulations, DBP appears at trace concentrations (<3%) but its Prop 65 status requires label disclosure regardless of concentration. It is one of several phthalate plasticizers being phased out in newer formulations in favor of non-phthalate alternatives.

Health & environment profile

VOC
no
Prop 65 listed
yes
Asthmagen
no
EPA Safer Choice
no
Aquatic toxicity
yes
Biodegradable
yes
Bioaccumulative
yes
Persistent
no
Ozone depleting
no
Microplastic
no
PFAS
no
Env. score
1/5
Purpose: Plasticizer in nitrocellulose lacquers and putties; improves flexibility and adhesion of the cured film

Common questions about Dibutyl Phthalate

What is Dibutyl Phthalate used for in car care?
Plasticizer in nitrocellulose lacquers and putties; improves flexibility and adhesion of the cured film
Is Dibutyl Phthalate a VOC?
No. Dibutyl Phthalate is not classified as a volatile organic compound (VOC).
Is Dibutyl Phthalate on California's Proposition 65 list?
Yes. Dibutyl Phthalate appears on California's Proposition 65 list.
Is Dibutyl Phthalate biodegradable?
Yes. Dibutyl Phthalate has a confirmed biodegradable profile.

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.