Study on primary microplastics in cosmetics: their isolation, spectral and thermal analysis

Eight samples of personal care and cosmetic products (PCCPs) available on the market were analyzed to isolate and characterize intentionally added polymer particles. In four of the samples, particles of synthetic polymers (microplastics, MP) were detected. Among the various types of PCCPs, the most abundant MP sources were glitter gels and hand cleaning pastes. Results demonstrate that the combination of FTIR and Raman spectroscopy, which is the most widely used approach for MP identification, is not always sufficient for the accurate detection and differentiation of synthetic polymers in the products analyzed. The use of independent methods (solubility tests and DSC thermal analysis) allowed us to achieve additional important information and helped prevent incorrect conclusions regarding the presence of microplastics in PCCPs. DSC thermal analysis proved to be particularly useful in cases wherein a combination of spectroscopic methods was ineffective in MP identification.