CD29 Collaborative patch testing audits: bridging dermatology and the cosmetics industry

Abstract

Patch testing is an important tool for dermatologists to identify contact allergens and irritants in cosmetic formulations. As cosmetic products evolve with new ingredients, collaboration between dermatologists and cosmetics companies through patch testing audits has become a strategic approach to evaluate allergenic potential and support product safety. This abstract explores the successful joint patch testing audits from the industry perspective. The cosmetics industry plays a crucial role in these audits – not only as a supplier of products but also as an active partner in consumer safety. When industry expertise is combined with dermatological knowledge, the rigour, transparency and impact of patch testing initiatives are significantly elevated. Dermatologists contribute clinical excellence, standardized methodologies and access to diverse patient populations, enabling robust assessment of sensitisation risks. Cosmetics companies provide formulation data, ingredient sourcing, manufacturer coordination for sample preparation and research to develop tailored testing protocols. Together, both parties codesign audit protocols that reflect real-world usage, ensuring that emerging allergen investigations are relevant to actual consumer experiences. The UK trade association for the cosmetics industry (CTPA, the Cosmetic, Toiletry and Perfumery Association) has partnered with British Society for Cutaneous Allergy dermatologists to jointly develop patch testing audits for three categories of cosmetic ingredients, to date. Audits on acrylate copolymers (2021–2022), alkyl glucosides (2023–2024) and anhydride copolymers (initiated in September 2025) have produced results that provide both parties with an accurate understanding of the allergenic potential of these ingredients. This partnership demonstrates a proactive approach to consumer safety. By combining clinical and industry expertise, these joint efforts ensure that allergen assessments are both scientifically rigorous and relevant to real-world product use, ultimately supporting safer cosmetic products for consumers.