Fragrance Allergens in Cosmetic Products: Current Analytical Strategies and Regulatory Challenges

Fragrance allergens are widely used in cosmetics and personal care products to make them more attractive to consumers. However, their presence has raised increasing concerns due to their potential to induce allergic contact dermatitis and other adverse health effects. As a result, regulatory authorities have progressively strengthened labelling requirements and restrictions for fragrance allergens in cosmetics, creating new analytical and compliance challenges for both industry and regulatory laboratories. In this context, the development of sensitive, selective, and reliable analytical methodologies has become essential for the identification and quantification of these compounds in complex cosmetic matrices. This review provides a comprehensive overview of analytical methodologies reported between 2015 and 2025 for the determination of fragrance allergens in cosmetic matrices, with a focus on sample preparation. Conventional extraction methodologies are critically discussed together with advanced, miniaturized and microextraction approaches. The advantages, limitations, and applicability for routine quality control and regulatory compliance are critically discussed. Chromatographic developments, including the use of multidimensional approaches, are assessed. Recent regulatory updates are examined, and the challenges related to allergen labelling, low-level detection, matrix complexity, standardization, and harmonization of analytical protocols are also addressed. Finally, future perspectives on innovative analytical tools, and green analytical chemistry approaches are highlighted.