Do these substances emit formaldehyde gas when heated?

In summary, the conversation discusses the potential release of formaldehyde gas from two substances, cyclomethicone and glyoxylic acid, when subjected to heat from a hair straightener or hairdryer. It is mentioned that cyclomethicone is commonly used in hair products and would not be used if it emitted formaldehyde, while glyoxylic acid is known to have an unpleasant odor and can cause irritation. The person who asked the question may have had a reaction to these substances and is seeking clarification on their potential for releasing formaldehyde. It is also noted that a quick internet search can provide more information on these compounds.
  • #1
Hey there,

Trying to confirm whether or not these substances emit formaldehyde gas when subject to heat of hair straightener and hairdryers. Both were ingredients in a keratin treatment i used at home and i had a crazy reaction (irritated skin, eyes, hair, nose and lungs) in the process of heating in the application process.

- Cyclomethicone
- Glyoxylic acid
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  • #2
Cyclomethicone - looking at the formula I'd say it was somewhat unlikely. It is in widespread use in hair products, deodorants, skin care products (and some other products as well) and it would not be used in hair products if a hairdrier caused it to release formaldehyde.

Glyoxylic acid is reported as having an obnoxious odour, and it can be an eye, skin and respiratory irritant - it is a weak acid, so that is to be expected.

Why did you mention formaldehyde anyway? Smell?

Given that there would likely be only small amounts of these in any hair treatment, why did you ask about this pair in particular?

I got the info within seconds using google, incidentally. It was easy to find.

And the above is just my opinion. I am not an expert on these compounds, just a normal chemist.
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Likes DrClaude
  • #3
I agree with DrJohn.

It is possible you have allergies. The compounds appear thermostable so it's unlikely to be formaldehyde unless your heat gun belongs to Area 51.

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