Percutaneous Absorption of UV Filters Contained in Sunscreen Cosmetic Products ─ Development of Analytical Methods

Zacarías León's thesis describes the development and validation of analytical methods to estimate the processes set in motion by percutaneous absorption of UV filters in sunscreen cosmetic products. León describes these methods in both in vitro and non-invasive in vivo methodologies. Currently dermatologists recommend the use of sunscreen products not only under conditions of extreme exposure to the sun but also in daily situations. However the chemical compounds in these products contain may lead to undesired processes and cause induced toxicity, estrogenic effects and endocrine activity. León establishes methods to investigate these effects and provides valuable information on the undesired side effects associated with the use of UV filters found in sunscreen products. The work in this thesis has led to a number of publications in renowned analytical chemistry journals.

Zacarias Leon obtained his PhD in 2012 from the University of Valencia (Spain). His research has been focused on bioanalytical chemistry (i.e., body disposition of cosmetic ingredients), using mainly liquid and gas chromatography techniques with mass spectrometry detection. His current research interests are both targeted and untargeted metabolomics, including structural elucidation chemistry, drug metabolism and biomarker discovery.