Allergen of the Day Immunity Research

Methylisothiazolinone (MI or MIT) and methylchloroisothiazolinone (MCI or CMIT)

The molecule methylchloroisothiazolinone  (CAS 26172-55-4) causes contact dermatitis and was seen in many products world wide  in preparations like cosmetics, lotions, moisturizers, sanitary wipes, shampoos, dish washing detergents, body and hand products, baby wipes, shampoos and even mouth washes.  Methylchloroisothiazolinone is often pared with Methylisothiazolinone, is a clear liquid with no fragrance tones.  It functions as a preservative  and cytotoxin. The contact skin allergies caused by Methylisothiazolinone are documented in journal articles and in the EU Scientific Committee on Consumer Safety (SCCS) in the document “THE SCIENTIFIC COMMITTEE ON COSMETIC PRODUCTS AND NON-FOOD PRODUCTS INTENDED FOR CONSUMERS”.

Contact Allergen of the year 2013 American Contact Dermatitis Society

Methylisothiazolinone – This chemical is used as a preservative in many cosmetics, lotions, and makeup removers; some of its side effects include flaky or scaly skin, breakouts, redness or itchiness, and moderate to severe swelling in the eye area.

What is Methylisothiazolinone?

Methylchloroisothiazolinone often causes contact dermatitis and persistent eczema and causes out breaks of with those who suffer psoriasis on the skin exposed to methylchloroisothiazolinone.  This chemical is listed as a known human immune system toxicant and skin allergen in EU Banned and Restricted Fragrances and Canada lists.   However, we still see it in products in the United States, South American, Africa and Asia.  This is also found as a food additive now.  Clinical we see are seeing and increase with contact dermatitis from this allergen. It is active at 15 parts per million.

Skeletal formula of methylisothiazolinone



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