Io
Iodopropynyl Butylcarbamate
Iodopropynyl Butylcarbamate
A preservative that keeps microbes out of a product at well under a tenth of a percent.
What it does
Its molecule carries an iodine atom. It’s often used alongside other preservatives in a formula.
The EU’s ingredient database lists it as a preservative (holds back germs in the product).European Commission, CosIng (© European Union, CC BY 4.0) · uses put in plain words by Drop ↗
The evidence, graded
expert consensusUS safety reviewers (1998) found iodopropynyl butylcarbamate (IPBC) mildly irritating in clinical tests. They judged it safe at up to 0.1%, but not in products meant to be sprayed, given its effects when breathed in by animals. Most products needed less than 0.0125%. In 2013 they decided not to reopen that review, and found the irritation and allergy data gave no reason to think it unsafe at up to 0.05%, the highest amount reported in use.Cosmetic 1998 · International Journal of Toxicology ↗
Graded per the methodology: strong · moderate · emerging · expert consensus. A weak source on a strong claim gets the weaker label.
Also known as
IPBC
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