title: [In vitro comparison of the efficacy and photostability of three sunscreen creams].
abstract: BACKGROUND
  While sun products are considered as cosmetics within the European Union, in the United States and Japan they are considered as medicines. Following the European market launch of the first sun product considered as a class-1 medical device, Daylong actinica, we compared products having different types of status.
  
  
  METHODS
  Three sun products underwent in vitro testing in order to determine their efficacy in terms of UVB and UVA protection, as well as their photostability. We used a classic cosmetic product (Nivea Sun 50+), a product displaying particular claims in terms of duration of efficacy (Dix20), and a medical device (Daylong actinica). The in vitro method used involves measuring the transmittance of a sample of the product applied to a polymethylmethacrylate plate using an integrating sphere spectrophotometer.
  
  
  RESULTS
  In terms of efficacy, the three products tested were compliant with the European recommendations concerning sun products. In view of the results, the labelling for Nivea Sun 50+ and Daylong actinica) can both display the wording "50+". However, their photostability was poor under our experimental conditions. For Dix20), the labelling that may be displayed is 50. This value gradually decreases to 20 after 10hours of irradiation, accounting for the displayed claim.
  
  
  CONCLUSIONS
  It is somewhat difficult to understand the coexistence on the market of products having different types of status without any prior establishment of clear limits in terms of indices, for example.
authors.affiliation: LPiC, MMS, EA 2160, Faculty of Pharmacy, université de Nantes, Nantes atlantique universités, 1, rue G.-Veil, BP 53508, 44000 Nantes, France.
authors.forename: C
authors.initials: C
authors.lastname: Couteau
authors.forename: L-J-M
authors.initials: LJ
authors.lastname: Coiffard
mesh_terms: D004348:Drug Labeling; D006801:Humans; D066298:In Vitro Techniques; D013053:Spectrophotometry; D013473:Sunscreening Agents / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D013473:Sunscreening Agents