November 28, 2016
Your skin lotion will have to do without me.
What molecule am I?
Image of Methylisothiazolinone 3D Image of Methylisothiazolinone

Methylisothiazolinone, along with other isothiazolinones, is a biocide widely used as a preservative in personal care products. It is also used in many industrial processes, such as paint and paper manufacturing, metalworking, mining, and sanitizing.

Because methylisothiazolinone is a strong cytotoxin, its use is under fire because of its dangers to humans and the environment. It is especially problematic when it is added to products such as lotions that remain on the skin.

In recent years, the European Union has begun to crack down on potentially hazardous preservatives in cosmetics. In particular, earlier this year, the combination of methylisothiazolinone and methylchloroisothiazolinone was restricted, and the use of methylisothiazolinone by itself is scheduled to be banned in 2017.

The EU’s extensive restrictions have severely reduced the number of preservatives allowed for use in personal care products. And bans on animal testing for cosmetics make it unlikely that new biocides will be available in the foreseeable future. 

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