Ectocrylene

Ectocrylene, also called Octocrylene or Octrocrilen, is an oily, clear yellow liquid which is not miscible with water. Octrylenes are a mixture of several isomeric compounds with structural elements of cyanoacrylates and cinnamic acid esters. Octrylene is used as sun protection filter in cosmetics and absorbs wavelengths between 280 and 320 nm with an absorption maximum at 303 nm (UVB).

The pronounced lipophilicity of the substance leads to a high bioaccumulation potential. Traces of octocriles have therefore been found for years in lakes and rivers, as well as in tap water.

Organic light protection filters are all those UV filters whose effect is not exclusively based on the inorganic, physically active substances titanium dioxide or zinc oxide. Organic, also known as chemical UV filters, are photoactive substances that are able to absorb light quanta in a certain wavelength range (ultraviolet radiation in the range of about 280 to 400 nm = ultraviolet radiation = UVB/UVA spectrum). The absorbed UV is then released as thermal energy without penetrating the skin. In this reversible photoisomerization, the energy of the absorbed photon must correspond to the energy required to lift an electron in the molecule of the filter substance from a lower to a higher orbit. In order to protect over the entire width of the wavelengths relevant to humans from 290 to 400 nm, several chemical filters with different absorption maxima are usually combined. With a suitable combination of organic and physical filters, the content of organic filters can also be reduced with the same UV protection. This is desirable, since especially photounstable organic UV filters can cause phototoxic and photoallergic reactions depending on their concentration in the finished product.

1. de Groot AC et al (2014) Contact and photocontact allergy to octocrylene: a review. Contact Dermatitis 70: 193-204