• Research

Study Shows Many Sunscreens Contain a Carcinogenic Compound

An organic sunscreen filter frequently used in sunscreens and anti-aging creams, octocrylene degrades within the bottles themselves into a known carcinogenic and endocrine disrupting compound: benzophenone. This is the result of a groundbreaking study conducted by researchers from the Laboratory of Biodiversity and Microbial Biotechnology of the Oceanological Observatory of Banyuls-sur-Mer (Sorbonne University/CNRS) in collaboration with their American colleagues, published in the journal Chemical Research in Toxicology on March 8, 2021. 

Industries producing octocrylene know that this molecule is contaminated with benzophenone and that the latter cannot be eliminated in its entirety during octocrylene production. In addition, the concentration of benzophenone in octocrylene-based manufactured products is considered "negligible" by the cosmetics industry. However, octocrylene degrades naturally into benzophenone within the packaging itself. During its study, the Franco-American research team discovered that this substance was present in the 15 commercial products tested. Moreover, the scientists demonstrated that the concentration of benzophenone in these cosmetics increases rapidly as the product ages.

The scientific community and the cosmetic industry commonly agree that both octocrylene and benzophenone are easily absorbed by the skin1. As such, octocrylene no longer meets U.S. FDA2 safety criteria, and accumulated scientific data indicates that it may be a reproductive toxicant, metabolic and endocrine disruptor. In addition, octocrylene is also described as environmentally toxic, affecting corals in swimming areas and potentially decreasing the resilience of coral reefs to climate change3. The fact that octocrylene products are contaminated with benzophenone in significant amounts therefore calls into question the overall safety of these products for public use.

Carcinogen, photomutagen and endocrine disruptor: what we know about benzophenone

In the United States, benzophenone is banned in food products and packaging and is listed as a carcinogen and developmental disruptor under California's Proposition 65. In mammalian model studies, benzophenone exposure induces liver cancer and lymphoma. It may also act as a photomutagen: in the presence of light, the rate of DNA damage increases, thus increasing the risk of skin cancers. Finally, benzophenone is also known to be an endocrine disruptor, affecting thyroid function and inducing anti-androgenic activity, which can retard testicular development and cause anatomical deformities to the female reproductive organs.

To date, octocrylene has already been banned in sunscreen products in some territories such as the U.S. Virgin Islands and the Republic of the Marshall Islands. Cosmetic products containing octocrylene are also banned in the Republic of Palau (Micronesia) since January 1, 2020. President Tommy Remengesau, Jr, who signed the ban, said, "Palau has identified an emerging environmental threat that is uniquely related to tourism: the use of sunscreens in outdoor recreation. Preemptive regulation of these chemicals and other risky contaminants is not only good policy, but also a manifestation of a traditional Pacific paradigm of conservation management. We should demand intensive, independent studies on the safety of all chemicals used in personal care products, and new research like this one further reinforces that imperative. Science must come first; we cannot gamble with the health of the environment.

The findings of this groundbreaking study provide new scientific evidence to argue that octocrylene-based products—and therefore benzophenone-contaminated products—can pose a threat to individual and public health, as well as to the environment. The team concludes: "Our results argue for the implementation of regulations based on the precautionary principle, with the objective of protecting public health and the environment.

1] Dermal absorption of benzophenone into the body can exceed 70%, according to studies conducted by Professor Howard Maibach and colleagues in the 1990s—a strong argument for a regulatory ban on benzophenone and octocrylene in fragrances and other topical products.
2] The Food and Drug Administration
[3] Findings from a previous study conducted by researchers in the Microbial Biodiversity and Biotechnology Laboratory, published on December 5, 2018 in the journal Analytical Chemistry: http://www.sorbonne-universite.fr/actualites/les-coraux-menaces-par-nos-cremes-solaires


Time-dependent benzophenone accumulation in commercial sunscreen products from the degradation of octocrylene, Craig A. Downs, Joseph C. DiNardo, Didier Stien, Alice M. S. Rodrigues and Philippe Lebaron, Chemical Research in Toxicology, 8 March 2021.
DOI: https://doi.org/10.1021/acs.chemrestox.0c00461


Philippe Lebaron

Professeur de microbiologie et d’écologie marine à Sorbonne Université

Didier Stien

Directeur de recherche au CNRS                                                                             

Marion Valzy

Service presse de Sorbonne Université

How to get prepared for the new academic year 2023-2024

Discover our step-by-step guide to get ready for the start of the new academic year. Learn everything there is to know from the application process to the beginning of the first term.

Préparer ma rentrée slider


All publications

Artisans Abroad

Par Fabrice Bensimon

British Migrant Workers in Industrialising Europe, 1815-1870


25 000



bachelor degrees


master degrees




Discover our courses catalog


The Faculty of Medicine teaches the 3 cycles of medical studies: from PASS (integrated into the faculty) to the 3rd cycle including DES, DESC, DU and DIU. The lessons are given mainly on two sites: Pitié-Salpêtrière and Saint-Antoine. The faculty also provides paramedical education: speech therapy, psychomotricity and orthoptics. The Saint-Antoine site includes a midwifery school.

Study | at the faculty of medicine

One of our riches is the diversity of students and their backgrounds. Sorbonne University is committed to the success of each of its students and offers them a wide range of training as well as support adapted to their profile and their project.

Associative life

One of our riches is the diversity of students and their backgrounds. Sorbonne University is committed to the success of each of its students.

21 393


17 527



Doctors in medecine and research


Research centers

Welcome to Sorbonne University's Faculty of Science & Engineering

A unique combination of courses and expertise

Our international study programmes are organised according to the major disciplinary areas of the faculty. They represent the graduate study programmes that are not strictly conducted in French or that could be suitable (in part) for non French-speaking students. They also reflect part of the diversity of the disciplines involved and the bi- and inter-disciplinary aspects of many of the courses we offer.


Research & Innovation

We rely on disciplinary skills and on interdisciplinary approaches to renew concepts, methods and research subjects and to focus on some of the crucial issues faced by our societies: transformations affecting the very construction of knowledge (data, AI), the treatment of complex objects (the environment, marine and ocean sciences, cultural heritage) or our contributions to addressing societal challenges (climate change, healthcare).

Study at | The Faculty of Science & Engineering

Our campuses offer different and unique experiences to our students, visitors and staff. Resources and support services are also available to ensure an equal chance at success to all.

Campus Life

In addition to the cultural activities and events organised throughout the year by our clubs and societies, the Parismus society organises numerous events, evenings and cultural visits that will help you discover France and its parisian life.







Sorbonne University's Faculty of Science & Engineering, Oriented towards excellence