# What’s Really in Our Sunscreens? > This case study reports a multi-technique characterization of two commercially available sunscreens—one mineral-based (TiO₂/ZnO) and one chemical-based—motivated by real-world differences in skin irritation. Volatile organic compounds in the chemical sunscreen were identified by GC–MS/TOF-MS both immediately after dispensing and after two hours of sunlight exposure; the post-exposure chromatogram showed a shifted chemical profile and new […] Source: https://covalent.com/resource-library/whats-really-in-our-sunscreens/ Updated: 2026-02-19T17:29:46+00:00 --- ![](https://spcdn.shortpixel.ai/spio/ret_img,q_cdnize,to_auto,s_webp:avif/covalent.com/wp-content/themes/covalent/assets/images/blog-default-banner.jpg) ![](https://spcdn.shortpixel.ai/spio/ret_img,q_cdnize,to_auto,s_webp:avif/covalent.com/wp-content/themes/covalent/assets/images/blog-mobile-banner.jpg) # What’s Really in Our Sunscreens? ![What’s Really in Our Sunscreens?](https://spcdn.shortpixel.ai/spio/ret_img,q_cdnize,to_auto,s_webp:avif/covalent.com/wp-content/uploads/2026/02/whats-really-in-our-sunscreens.jpg) Feb 11, 2026 This case study reports a multi-technique characterization of two commercially available sunscreens—one mineral-based (TiO₂/ZnO) and one chemical-based—motivated by real-world differences in skin irritation. Volatile organic compounds in the chemical sunscreen were identified by [GC–MS](https://covalent.com/techniques/chemical-analysis/gas-chromatography-mass-spectroscopy-gc-ms/)/TOF-MS both immediately after dispensing and after two hours of sunlight exposure; the post-exposure chromatogram showed a shifted chemical profile and new peaks consistent with UV-driven reactions/photodegradation products. Trace metals were quantified by [ICP-MS](https://covalent.com/techniques/chemical-analysis/inductively-coupled-plasma-mass-spectroscopy-icpms/) across a broad elemental panel; both sunscreens contained detectable metals, but all were measured at concentrations below topical toxicity thresholds. Finally, [SEM-EDS](https://covalent.com/techniques/electron-microscopy/scanning-electron-microscopy-sem/) was used to examine mineral sunscreen particulates, revealing two distinct nanoparticle morphologies and confirming (via elemental mapping and spectra) a relatively uniform TiO₂ distribution alongside Zn-rich, rod-like agglomerates that likely contribute to visible “white cast.” Subscribe to Our Newsletter Subscribe to our newsletter for the latest updates, insights, and breakthroughs - delivered straight to your inbox.