Bu
Butane
Butane
A gas kept liquid under pressure that carries sprays and foams out of the can.
What it does
As you press the nozzle, it turns from liquid to gas and pushes the product out, then evaporates into the air.
The evidence, graded
expert consensusUS safety reviewers judged propane, isobutane, isopentane and butane safe as used in 1982, and kept that verdict in reviews published in 2005 and 2025. They noted that these are propellants, and that despite very high amounts in some leave-on products they evaporate completely and don’t stay on skin. Newer studies showed no harm to development or reproduction from propane or butane, and their tests for DNA damage were negative.Tucker 2025 · International Journal of Toxicology ↗
Graded per the methodology: strong · moderate · emerging · expert consensus. A weak source on a strong claim gets the weaker label.
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