Isooctane
molecular structure · PubChem
AKA: 2, 4-Trimethylpentane, Pentane, ISO-OCTANE, HSDB 5682
Synthetic
Solvent
Not Clean
2,2,4-Trimethylpentane is released to the environment through the manufacture, use, and disposal of products associated with the petroleum and gasoline industry. During an accident, 2,2,4-trimethylpentane penetrated the skin of a human which caused necrosis of the skin and tissue in the hand and required surgery. No other information is available on the acute (short-term) effects in humans. Irritation of the lungs, edema, and hemorrhage have been reported in rodents acutely exposed by inhalation and injection. No information is available on the chronic (long-term), reproductive, developmental, or carcinogenic effects of 2,2,4-trimethylpentane in humans. Kidney and liver effects have been observed in rats chronically exposed via gavage (experimentally placing the chemical in the stomach) and inhalation. EPA has not classified 2,2,4-trimethylpentane with respect to potential carcinogenicity.
Solubility PRACTICALLY INSOL IN WATER; SOMEWHAT SOL IN ABS ALC; SOL IN BENZENE, TOLUENE, XYLENE, CHLOROFORM, ETHER, CARBON DISULFIDE, CARBON TETRACHLORIDE, DMF & OILS, EXCEPT CASTOR OIL.
Formula
C8H18
Mol. Weight
114.23
CAS #
540-84-1
Form
Liquid
State
Isooctane appears as a clear colorless liquid with a petroleum-like odor. Less dense than water and insoluble in water. Vapors are heavier than air.
Functions
Solvent
Dissolves other ingredients so they distribute evenly in the formula. Often the invisible "base" everything else is mixed into.
Quells irritation
Traditional Use
A synthetic hydrocarbon developed in the mid-20th century as a volatile solvent for cosmetics. Used to replace or supplement traditional solvents and to improve product spreadability and drying time.
Skin Types
●all-skin-types
Best For
General
Pregnancy & Breastfeeding Safe
Yes
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.
Verified Jun 2026
Data: PubChem · CosIng · EWG · CIR