Quaternium-15

Also known as: methenamine 3-chloroallylochloride

Higher concernunder our published method

By NordicScan Evidence Engine · generated from structured evidence records · source spans verified by automated gates · Reviewed 2026-07-08 · Evidence snapshot geo-wave1-evidence-snapshot-2026-07-08 · Scoring engine det_v3 · how we score.

What it is

Quaternium-15 is a preservative that belongs to the formaldehyde-releaser ingredient family.

Why people ask

People ask because it can be discussed as a named preservative and as part of the formaldehyde-releaser labelling family.

What our method flags — by use

Cosmetic · EU cosmetics (prohibited substance)

In EU cosmetics, our method rates quaternium-15 as higher-concern: the EU added it to the prohibited-substances list (Annex II) in 2019, ending its former preservative listing.

The EU restricted by Regulation (EU) 2019/831 quaternium-15 — prohibited in cosmetic products (Annex II).

Authority / source	Finding (our paraphrase)	Evidence tier	Date	Link
European Union / EUR-Lex	The EU restricted by Regulation (EU) 2019/831 quaternium-15 — prohibited in cosmetic products (Annex II).	authority_regulatory	2019-05-22	source
European Union / EUR-Lex	The EU restricted by Regulation (EU) 2019/831 quaternium-15 — added to the prohibited-substances list (Annex II) of the Cosmetics Regulation; the former Annex V preservative entry no longer applies.	authority_regulatory / --	2019-05-22	source
European Union / EUR-Lex	The EU restricted by Regulation (EU) 2022/1181 finished cosmetic products containing listed formaldehyde releasers to carry the warning "releases formaldehyde" above 0.001% released formaldehyde.	authority_regulatory / --	2022-07-08	source

Evidence coverage for this use: Good (computed from source count × authority tier × recency; signals depth, does not change the concern band).

How this moves a product’s score

On a product's score, quaternium-15 contributes a higher concern signal: it is a prohibited substance in EU cosmetics (Annex II), and our method weights a regulator prohibition at the top of the ingredient's contribution.

Nordic Scan provides ingredient information and a concern score under our published method, for general consumer research. It is not medical advice and not a medical device, and does not diagnose, treat, cure, or prevent any disease, or determine the safety of any product. Decide for yourself.

This is what Quaternium-15 is. What’s in the products you buy? Scan a label and see the concern signals our method flags. Get the app.

Reviewed 2026-07-08 · Evidence snapshot geo-wave1-evidence-snapshot-2026-07-08 · Scoring engine det_v3 · Sources checked 2026-07-08 · See how we score.