Parabens, phthalates, and fragrance are ingredients I often talk about, but I thought it would be good to highlight a lesser known ingredient that should be avoided as well. I have many friends that struggle with eczema. It can be itchy and annoying and hard to get rid of. The ingredient methylisothiazolinone should be avoided if you struggle with eczema.
What is methylisothiazolinone?
Often called MI, Methylisothiazolinone is a biocide, a chemical substance that controls or kills microorganisms. MI is often found in antibacterial and cleaning products and is used as a preservative.
MI is another chemical that has been banned for use in personal care products in the European Union (EU) but is still allowed in America. As a reminder, our cosmetics industry uses roughly 10,000 industrial chemical ingredients in personal care products, and the vast majority have never been assessed for safety by any publicly accountable body.
Why avoid methylisothiazolinone?
Methylisothiazolinone can irritate the skin and In 2013, the American Contact Dermatitis Society named MI the contact allergen of the year. Contact dermatitis is a kind of eczema caused when the skin reacts to an allergen. The allergen can be in a product that is applied to the skin or inhaled or ingested. The National Eczema Association names MI, along with fragrance, the metals nickel, cobalt, and chromium, formaldehyde, and other harmful chemicals as the main triggers for contact dermatitis.
There has also been some concern that MI may be related to organ system toxicity (1) and neurotoxicity (2). This means that Methylisothiazolinone may impact the development and function of the organ system or central and/or peripheral nervous system. Sounds like a good chemical to avoid, right?
As you read labels, Methylisothiazolinone is one to watch out for.
If you’re looking for more help reducing your exposure to harmful chemicals get my Guide to Toxin Free Living.
(1) Rohm & Haas (2002). Acute Inhalation toxicity study in rate (methylisothiazolinone 53.52% active ingredient). Rohm & Haas Chemicals, LLC Report, 06R-1002.
(2) Burnett, C. L., Bergfeld, W. F., Belsito, D. V., Klaassen, C. D., Marks, J. G., Shank, R. C., … & Andersen, F. A. (2010). Final report of the safety assessment of methylisothiazolinone. International journal of toxicology, 29(4 suppl), 187S-213S.
