Formaldehyde releasers and isothiazolinones

In short: These are preservatives that often cause contact allergies. Formaldehyde releasers slowly release formaldehyde, isothiazolinones (MI, MCI) are very strong allergens.

In more detail: Formaldehyde releasers include DMDM hydantoin, imidazolidinyl urea, diazolidinyl urea, quaternium-15 and sodium hydroxymethylglycinate. Methylisothiazolinone (MIT) has been banned in leave-on products in the EU since 2017 and is allowed in rinse-off products only at very low concentration.

Our context: Both groups lead to the highest deductions in cosmetics in the product scanner.

In Depth

• Symptoms: redness, itching, eczema on hands, face or scalp.
• Where: shampoos, shower gels, wet wipes, paints and cleaning products.
• Test: Dermatologists offer the patch test.
• Avoiding: Choose products without these substances and read the list.

See also: Parabens, INCI: reading cosmetic ingredients