In the European Union, cosmetics are regulated under Regulation (EC) No 1223/2009, which establishes harmonised rules to ensure a high level of protection of human health for products placed on the market. This regulation applies to any substance or mixture intended for contact with external parts of the human body, such as skin, hair, nails, lips, and external genital organs, or with teeth and the mucous membranes of the oral cavity, for the purposes of cleaning, perfuming, changing appearance, protecting, keeping in good condition, or correcting body odour. Before a cosmetic product can be marketed, it must undergo a rigorous safety assessment to ensure that it does not present a risk to human health when used under normal or reasonably foreseeable conditions.
Every cosmetic manufacturer or the designated “responsible person” must prepare a Product Information File, known as the PIF, which contains all data demonstrating that the product is safe. One of the most important elements of the PIF is the Cosmetic Product Safety Report (CPSR). This report is divided into two parts: the first includes detailed safety information such as ingredient properties, toxicological data, formulation characteristics, stability, microbiological quality, packaging compatibility, and exposure assessment. The second part contains the safety assessment, which is a professional opinion written by a qualified safety assessor holding appropriate scientific qualifications, typically in toxicology, pharmacy, or a related discipline. The assessor must evaluate potential risks by considering the toxicological profile of each ingredient, systemic exposure, and cumulative exposure from multiple products used on the skin. Special attention must be given to vulnerable populations such as children, pregnant women, and people with skin conditions.
The European Scientific Committee on Consumer Safety (SCCS) provides official guidance for assessors in its “Notes of Guidance for Testing of Cosmetic Ingredients and Their Safety Evaluation,” currently in its 12th revision. This document outlines best practices for evaluating ingredients, promoting the use of non-animal alternative methods such as in vitro assays, computational toxicology, integrated approaches to testing and assessment, and in silico modelling. Because the use of animals for testing cosmetic ingredients or finished products has been banned in the EU since 2013, manufacturers must rely on validated alternative methods. These approaches are recognised internationally and are continuously being updated to reflect advances in toxicology and biomedical science. The safety assessor must consider all available scientific evidence, including published literature, historical data, and relevant data from analogous ingredients.
Efficacy evaluation is another critical element of cosmetic development. While cosmetics are not intended to treat or cure diseases, the claims made about them must be truthful, substantiated, and not misleading to consumers. Under Commission Regulation (EU) No 655/2013, companies must support any marketing claim with adequate and verifiable evidence. For example, statements such as “reduces wrinkles,” “provides 24-hour hydration,” or “improves skin elasticity” must be backed by appropriate testing. Depending on the nature of the claim, substantiation can come from instrumental measurements, consumer perception studies, or controlled in vivo tests. Common scientific methods include corneometry for skin hydration, cutometry for skin elasticity, profilometry for wrinkle analysis, and transepidermal water loss measurements to assess barrier function. Subjective evaluation by expert graders or consumer self-assessment questionnaires is also frequently used. Study designs must follow ethical and scientific standards, including informed consent, clearly defined inclusion criteria, blinding when applicable, statistical analysis plans, and adverse event monitoring. Results are compiled in a claims substantiation dossier that must be kept within the PIF and made available to authorities upon request.
Once a product is placed on the market, manufacturers must maintain continuous oversight through a process known as cosmetovigilance. This involves collecting and evaluating reports of undesirable or serious undesirable effects that occur during product use. If such effects are identified, the responsible person must notify the competent national authorities and take corrective actions if necessary, such as reformulating or withdrawing the product. The PIF and CPSR must be retained for at least ten years after the last batch of the product has been released, and any significant change to the formula, packaging, or intended use requires a reassessment of safety and efficacy.
The industry also faces ongoing challenges as science and consumer expectations evolve. The prohibition of animal testing has driven the development of alternative approaches, such as reconstructed human epidermis models, cell culture assays, and computational toxicology methods. These tools make it possible to assess skin irritation, corrosion, sensitization, and phototoxicity without the use of animals. However, not all toxicological endpoints can yet be fully addressed by non-animal methods, which means assessors must integrate diverse data sources using weight-of-evidence approaches. Meanwhile, new areas such as nanomaterials, endocrine disruptors, microbiome-related products, and personalised formulations require updated testing strategies and regulatory scrutiny. The SCCS continues to issue scientific opinions on these emerging topics to ensure consumer safety.
The efficacy side is also becoming more complex. Consumers are increasingly demanding measurable performance and transparency, which pushes companies to conduct more sophisticated and reproducible studies. Technologies such as high-resolution imaging, bioinstrumentation, and artificial intelligence-based data analysis are improving the accuracy and reproducibility of cosmetic claim validation. For instance, advanced 3D skin imaging systems can quantify wrinkle depth or pigmentation changes with high precision, while AI-driven analysis can standardise subjective consumer feedback. These innovations are helping bridge the gap between marketing and scientific validation.
Ultimately, clinical evaluation of cosmetics is a multidisciplinary effort combining toxicology, dermatology, analytical chemistry, and regulatory science. Proving safety and efficacy requires more than laboratory tests; it involves ongoing scientific judgement, ethical conduct, and transparent documentation. Regulation (EC) No 1223/2009 ensures that every cosmetic product sold within the EU meets high standards for consumer health protection. By implementing robust safety assessments, substantiating performance claims, maintaining effective cosmetic vigilance, and following scientific advancements, the cosmetics industry can continue to innovate responsibly while maintaining the trust of consumers and regulators alike.