BleachQ: What is hair bleach made of? Is bleach harmful to your health?
A: The bleaching agents used to lighten the hair vary with the level of lightening desired. For small amounts of lift and lightening of the hair's color, hydrogen peroxide is a common bleaching agent. The concentration of hydrogen peroxide used for lightening the hair is much stronger than the solution used to disinfect and treat wounds. It can irritate the bare skin with which it comes in contact, but usually only becomes an issue when an individual is sensitive to it.
For high-lift bleaching processes, most bleach additives include ingredients like Potassium Persulphate, which helps to whiten and lift color, and Sodium Metasilicate (which acts as an alkaline component and helps the bleach penetrate the hair shaft. There are other similar ingredients that may be found in the bleach, and these ingredients make-up a product considered to be an "off-the-scalp" bleaching agent. These products are not intended to come in contact with the skin and are likely to cause chemical burns with exposure.
Not even the mildest bleaching agents could be considered "healthful" and are especially harmful if ingested, or if they get into the eye or other mucous membrane. Always read any packaging carefully before use in order to make sure you know what to do in case of emergency.
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