Targeted Determination of Residual Sex Hormones in Cosmetics Using Magnetic Solid-Phase Extraction with Isotope-Labeled Internal Standards by UHPLC-MS/MS

The study developed a method using magnetic solid-phase extraction and isotope-labeled internal standards for detecting trace sex hormones in cosmetics via UHPLC-MS/MS. It was applied to 116 cosmetic samples, revealing trace progestins and estrogens in 10 samples, with progesterone frequently detected in hair loss prevention products at concentrations from 6.5 to 70.5 μg/kg. The method demonstrated high sensitivity, precision, and environmental friendliness, with a recovery range of 71.7% to 116.2% and a relative standard deviation of 1.6% to 8.3%. A safety evaluation indicated a low health risk from progesterone exposure, with a margin of safety significantly above the threshold of concern.