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Butylene Glycol
Butylene GlycolHydrator
It holds water and dissolves other ingredients. In one clinic’s patch tests, fewer people reacted to it than to propylene glycol.
The evidence, graded
moderateIn one US clinic’s patch tests of 893 patients, 13 (1.46%) reacted to butylene glycol and 53 (5.94%) to propylene glycol; 46.2% of those allergic to butylene glycol also reacted to propylene glycol. US safety reviewers found no allergy in a repeated patch test and judged it safe as used in cosmetics in 1985.Ekstein 2024 · Dermatitis ↗
expert consensusUS safety reviewers’ 1985 report describes butylene glycol and three related glycols as thick liquids. Cosmetics use them to draw in water, keep oil and water mixed, keep films flexible and dissolve other ingredients.Cosmetic 1985 · Journal of the American College 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
BG
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