The revised COLIPA in vitro UVA method. (21st September 2012)

• Record Type: Journal Article
• Authors: Moyal, D.; Alard, V.; Bertin, C.; Boyer, F.; Brown, M.W.; Kolbe, L.; Matts, P.; Pissavini, M.
• Is Part Of: International journal of cosmetic science. Volume 35:Number 1(2013:Feb.)
• Page Start: 35
• Page End: 40
• Publication Date: 2012-09-21
• Subjects: Cosmetics -- Periodicals; 668.5505
• DOI: 10.1111/j.1468-2494.2012.00748.x
• Languages: English
• ISSNs: 0142-5463

Abstract

<abstract abstract-type="main" id="ics748-abs-0001"> <title>Synopsis</title> <p>A multicentred study derived from the COLIPA <italic>in vitro </italic>UVA method was performed to assess the influence of test conditions on UVA protection factor (UVAPF) values in terms of amplitude, reproducibility between laboratories and correlation with <italic>in vivo </italic>UVA results. Eight products with a range of <italic>in vivo </italic>UVAPF from three to 29 were used. Two different types of plates, namely high‐roughness (5 μm) and low‐roughness (2 μm) plates, were used with a different application rate for each (1.3 mg cm<sup>−2</sup> and 0.75 mg cm<sup>−2</sup> respectively). The UVR dose applied to both plate types followed the same principle as the original test (1.2 J. cm<sup>−2</sup> × UVAPF0). Strong, significant correlations between <italic>in vitro</italic> and <italic>in vivo </italic>UVAPF values were observed for both plate types (Pearson correlation > 0.9, <italic>P</italic> ≤ 0.01). The correlation and slope obtained with the low‐roughness plates confirmed the previous results obtained by COLIPA. Across all laboratories, higher UVAPF values were obtained on the high‐roughness plates (<italic>P</italic> < 0.01). Reproducibility of UVAPF values between laboratories was comparable between the two plate roughness values (low roughness, COV = 8%; high roughness, COV = 12%). Considering the <italic>in vitro</italic>/<italic>in vivo</italic> comparisons, a regression slope of 0.83 was observed for the low‐roughness plates, in comparison with a value of 1.05 for the high‐roughness plates. The accuracy of the method was improved, therefore, with the use of the high‐roughness plates. With a constraint to recommend the use of only one plate type in the COLIPA UVA <italic>in vitro</italic> Test, the high‐roughness plate was selected on an on‐going basis to limit variability of results and to provide better accuracy with <italic>in vivo</italic> data.</p> </abstract>