Cyclopentasiloxane

Cyclopentasiloxane 1
molecular structure · PubChem CID 10913
AKA: Silicone
Synthetic
Emollient
Solvent
Skin Conditioner
Hair Care
Silicone
Not Clean
OriginCyclopentasiloxane is a cyclic siloxane compound synthesized from silicon-based raw materials in the organosilicon chemical family. It is produced through controlled polymerization and cyclization of siloxane monomers via catalytic processes.
Decamethylcyclopentasiloxane
Formula
C10H30O5Si5
Mol. Weight
370.77
CAS #
541-02-6
Form
Liquid
State
Liquid
Skin Types
●all-skin-types
Best For
General
Pregnancy & Breastfeeding Safe
Yes
Functions
Hair Conditioning
A catch-all term for ingredients that improve how skin looks and feels — softer, smoother, more supple. The workhorse behind most moisturizers.
Skin Conditioning
A catch-all term for ingredients that improve how skin looks and feels — softer, smoother, more supple. The workhorse behind most moisturizers.
Emollient
Fills in the tiny cracks between skin cells to make everything feel smooth and soft. The "silky finish" ingredient.
Solvent
Dissolves other ingredients so they distribute evenly in the formula. Often the invisible "base" everything else is mixed into.
Locks In Moisture
The paper trail
🔬Peer-reviewed1 paper →
⚖️Regulatory1 listing →
🛡️Safety-assessed2 reviews →
Counts, not a verdict. A listing isn't a study. The trail, you decide.
EWG
4
CIR
Safe as used
Pregnancy
Yes
CIR Safety Findings
Not a Skin Irritant
2 studies / 2 not irritating (CIR 497)
Not a Sensitizer
4 studies / 4 not sensitizing (CIR 497)
Dermal Absorption 0.022–1.54%
5 animal and lab (in vitro) studies in the CIR safety assessment (CIR 497)
Regulatory Status
USA✔ permitted
EU⚠ restricted
JAPAN⚠ restricted
CANADA⚠ restricted
Verified Jun 2026
Data: PubChem · CosIng · EWG · CIR