Every morning, it’s the same thing: you draw your straightener to display beautiful shiny hair. The problem ? This common daily object could considerably harm your health. According to a new study, ten to twenty minutes from smoothing thus expose you to more than 10 billion nanoparticles.
Smoothing leads to the release of billions of harmful particles
According to this work, broadcast in the journal Environmental Science and Technologyhair care, and in particular smoothing, constitute an unknown source of pollution. Indeed, by combining certain hair products usually without danger (shampoos, lotions, gels, oils, waxes and sprays) with intense heat (150 ° C), volatile chemicals begin to deteriorate. And concretely, a cloud of chemicals invades air, whose famous nanoparticles which can accumulate in different organs. In detail, ten to twenty “hot” styling is enough to be exposed to more than 10 billion nanoparticles.
“The results of our work are really very worrying”, Confirms the principal researcher, Dr. Nusrat Jung. “”Studies of this type had never been carried out before. Thus, the public has so far been little aware of the potential health risks represented by their daily hair habits “.
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Siloxane D5, a compound in the viewfinder of researchers
In their previous work, Dr. Nusrat and his doctoral student, Jianghui Liu, had already shown that thermal treatments gave off large quantities of Siloxane D5, a prized substance for its smoothing and texturing properties.
The European Chemicals Agency had already classified Siloxane D5 as a compound “very persistent and very bioaccumulative“, since it stays in the environment for a long time and can accumulate in living organisms. When heated, it also breaks down and forms volatile compounds, potentially irritating for respiratory tract.
Smoothing, brushing, loops: how to avoid being exposed to these chemicals?
In order to avoid the potential risks linked to the inhalation of nanoparticles, the researchers recommend that it completely avoid hair care, especially when used with a straightening iron (or any other heating tool, such as curling iron).
If this is not possible, scientists advise to try to reduce your exposure to nanoparticles as much as possible, by choosing products without volatile compounds or with low harmful formulations, by airing your interior, by carrying a filter mask and by spacing the use of hair care and/or heating tools.