Ethylhexyl salicylate, also known as octisalate, is an organic compound that belongs to the class of salicylates (derived from salicylic acid). It is used in sunscreens as a UV filter due to its ability to absorb harmful UVB (ultraviolet) rays that can damage the skin. Its use is restricted in the European Union and the United States to a maximum concentration of 5% in cosmetic products.
As its chemical structure is very similar to that of other molecules suspected of being endocrine disruptors, in 2018, the European Chemicals Agency (ECHA) requested further testing to determine the toxicity of this UV filter. The Agency specifically cites three studies showing the in vitro (in a test tube in a laboratory) effects on male and female hormones. However, to date, the endocrine-disrupting potential of this chemical has not yet been proven in vivo (in a living organism). A 2012 study reported by ECHA on its database shows a significant reproductive and developmental toxicity of octisalate in rats. The reported effects were an increase in gestation length and a difference in offspring weight gain. Delayed growth and liver hypertrophy were also observed in rats. These effects have not been proven in humans, but appropriate caution should be exercised in pregnant women. The industry has also reported a risk of skin irritation to the ECHA but at much higher doses than those associated with exposure from cosmetic products. Lastly, the ECHA withdrew its request for further evaluation in 2022, as the Agency is awaiting the conclusions of the assessment of salicylic acid, a compound in the same chemical family, will make it possible to better assess its potential to disrupt the endocrine system. The Agency has stated that a request for an assessment can be resubmitted at a later date if concerns persist. Some cases of allergic reactions have also been reported.
From an environmental perspective, in the European Union, the majority of manufacturers have reported very high toxicity for aquatic life to the ECHA. Moreover, a study in the ECHA database shows evidence of a disturbance in the reproduction of small aquatic invertebrates. As these species are at the bottom of the food chain, this could lead to dramatic negative impacts on the entire marine ecosystem. Some studies show that octisalate is present in coral tissue and sediments in many seas, oceans, lakes, and rivers.
Sources :
ECHA. Substance infocard : 2-ethylhexyl salicylate. https://echa.europa.eu/fr/substance-information/-/substanceinfo/100.003.877
ECHA (2018). Justification Document for the Selection of a CoRAP Substance : 2-ethylhexyl salicylate. 20/03/2018. https://echa.europa.eu/documents/10162/1129b382-579f-b108-3925-24cb573fc951
ECHA. Registration dossier : 2-ethylhexyl salicylate. https://echa.europa.eu/fr/registration-dossier/-/registered-dossier/14203/6/2/5
US EPA. Comtox database : 2-Ethylhexyl salicylate. https://comptox.epa.gov/dashboard/chemical/details/DTXSID7040734
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