Cited skincare — every flag names its source, no upsell.What it does
It spread quickly as a preservative after parabens fell out of favor in the late 2000s, and within years became one of the most-cited skin allergens in patch-test surveys. Unlike in the EU, products sold in the US may still contain it, even ones you leave on. If preservatives or fragrance have bothered your skin, avoid it, even in shampoo and body wash.
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
moderateFragrance, essential oils, denatured alcohol and certain preservatives (methylisothiazolinone, the formaldehyde-releasers) are the usual suspects on sensitive skin. In the patch-test data read here — patients whose dermatitis was linked to a cleanser — the preservative quaternium-15 topped the list at 11.2% and fragrance mix I came fifth at 7.7%. Test a new product on a small patch of skin before you use it on your face.Warshaw 2018 · Dermatitis ↗ expert consensusSCCS/1521/13 (adopted 12 December 2013, revised 27 March 2014) assessed sensitization only. It found that 100 ppm MI in cosmetic products is not safe for the consumer. For leave-on products, including wet wipes, no safe concentration for inducing or eliciting contact allergy had been adequately demonstrated. For rinse-off products it considered 15 ppm (0.0015%) safe for inducing contact allergy, with no information on elicitation.SCCS 2013 · European Commission SCCS (adopted 12 December 2013) ↗ Graded per the methodology: strong · moderate · emerging · expert consensus. A weak source on a strong claim gets the weaker label.
Browse all 1238 ingredients — grouped by what they do, each with whatever evidence we can cite.
This page is public so a shared ingredient card always has its sources behind it — and so you can check them without an account.
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