L'Oréal Issues Voluntary Recall of Benzoyl Peroxide Products Over Benzene Concerns

L’Oréal announced today it is recalling all lots of its acne treatment Effaclar Duo in the US due to concerns over benzene contamination.¹ The product, sold under the La Roche-Posay brand, contains benzoyl peroxide (BPO).

Valisure, an independent testing laboratory, first reported benzene contamination in several BPO-containing acne products more than a year ago,² urging the US Food and Drug Administration (FDA) to take action.

The agency has not yet commented on whether additional recalls will follow.

L’Oréal stated that testing found trace levels of benzene in one lot of Effaclar Duo, leading the company to work closely with the FDA to proactively recall the product.

The company also announced that an improved formulation, which has been in development since 2024, will soon be available.

Click here for exclusive insights from Christopher Bunick, MD, PhD.

Stay tuned for additional updates.

Preceding Developments

Over the past year, multiple subsequent studies have investigated benzene contamination in BPO products. Research published in Journal of Investigative Dermatology confirmed widespread benzene contamination in 111 BPO products from major US retailers.³

Another study in JAMA Dermatology found that benzene levels increased with high-temperature processing but could be mitigated with antioxidants like BHT, highlighting the role of formulation and storage in contamination.⁴ While the chemical link between BPO and benzene is well established, the long-term health risks remain uncertain.

Most recently, a study published in the JID analyzed BPO and its potential link to malignancies, finding a strong signal of increased cancer-related adverse event (AE) reports among BPO users. Using data from the FDA’s Adverse Event Reporting System, researchers identified 452 AE cases from 2019 to Q1 of 2024, with 23 (5.09%) classified as neoplasms, including skin and breast cancer. The study noted that reports of neoplasms increased significantly in the last 2 years.⁵

Statistical analysis showed high reporting odds ratios for malignant neoplasms, skin cancer, and breast cancer, particularly in Proactiv products. While the study does not establish causality, it highlights concerns over benzene contamination in BPO products, aligning with prior research on the topic.

Researchers, including Dermatology Times Editor in Chief Christopher Bunick, MD, PhD, emphasize the need for further studies to assess the long-term safety of BPO, particularly regarding its formulation, storage, and potential to generate benzene.

“The chemical formation of benzene from benzoyl peroxide is well established. Recent research has demonstrated many benzoyl peroxide products have benzene concentrations exceeding the emergency or conditional FDA limit of 2 ppm benzene," said Bunick in a previous interview with Dermatology Times. "While these products are not in line with FDA regulatory policy, the health implications of benzene exposure from BPO products on consumers and patients is less understood. This new research in JID does not establish causality or potential for risk, but does identify a malignancy signal in the FDA’s own adverse event reporting database that warrants further studies into BPO.”

References

1. Edney A. L’Oreal recalls acne treatment on cancer-linked chemical. Bloomberg Law. March 10, 2025. Accessed March 10, 2025. https://news.bloomberglaw.com/health-law-and-business/loreal-recalls-acne-treatment-in-us-on-cancer-linked-benzene
2. Valisure citizen petition on benzene in benzoyl peroxide drug products. Valisure. March 5, 2024. Accessed March 10, 2025. https://assets-global.website-files.com/6215052733f8bb8fea016220/65e8560962ed23f744902a7b_Valisure%20Citizen%20Petition%20on%20Benzene%20in%20Benzoyl%20Peroxide%20Drug%20Products.pdf
3. Kucera K, Zenzola N, Hudspeth A, et al. Evaluation of benzene presence and formation in benzoyl peroxide drug products. J Invest Dermatol. 2024 Oct 7. doi:10.1016/j.jid.2024.09.009
4. Barbieri JS, Rubin CB, Pham JP, Wong M. The role of formulation in benzene formation in benzoyl peroxide products. JAMA Dermatol. 2025 Feb 12. doi: 10.1001/jamadermatol.2024.6443
5. Zhou S, Yan S, Ming S. A comprehensive study on adverse reactions of benzoyl peroxide (BPO) in dermatological aesthetics utilizing the FAERS database. J Cosmet Dermatol. 24: e16787. https://doi.org/10.1111/jocd.16787