It is an essential for summer vacations. Sun protection is strongly recommended in case of exposure to UV rays emitted by the sun. But if some vacationers are tempted to take their half-used tube of sunscreen from the previous year to the beach, it’s not a very good idea.
If the gesture is economical, the National Medicines Agency (ANSM) invites you to “respect the expiration date and the storage period after opening indicated on the packaging”.
“In fact, over time the filters tend to degrade and, therefore, reduce the effectiveness of the protection,” explain the health authorities.
compounds that break down
“Sun protection products are products that are subject to particular temperature rhythms and restrictions,” insisted Dr. Christine Lafforgue, dermopharmacologist, from the Allo Doctors site. “It’s hot, I get home, they’re at room temperature, I go outside, they’re back in the sun, these are life cycles that disrupt the formulation and accelerate the degradation of all the molecules inside.”
This is not without health consequences. At issue is octocrylene, a chemical compound used in many sunscreens to filter out UV rays. If this is effective, it gradually breaks down into benzophenone, a suspected carcinogenic and endocrine-disrupting compound, a French-American study concluded in 2021.
“Even in a closed tube, the product is transformed,” specifies Marc Perrussel, dermatologist-oncologist and physician at the University Hospital of Rennes (Ille-et-Vilaine) in Parisian.
Adverse effects on the environment
Beyond the sanitary component of octocrylene, its harmful effects on the environment and in particular on corals have also been pointed out by the National Health Security Agency (Anses). The latter also transmitted last May to the government a request to restrict theoctocrylene, according information from France info.
However, there are more and more sunscreens that do not contain this component that breaks down into benzophenone.
In any case, it is advisable to respect the expiration dates indicated on sunscreen products and keep them away from moisture, heat and light to limit their deterioration.
Source: BFM TV
