Benzoyl peroxide, a common ingredient in formulations for the treatment of acne-prone skin, has come under scrutiny following a 2024 study by Valisure published in Environmental Health Perspectives.1 The research found that benzoyl peroxide products can release benzene— unacceptably toxic, carcinogenic chemical substance—when stored at typical body or transport temperatures. This revelation has sparked alarm among consumers and formulators alike, especially given the increasing scrutiny on ingredient safety in personal care products. Following this study, several over-the-counter benzoyl peroxide containing products have been voluntarily recalled due to the detection of elevated benzene levels, a known human carcinogen.
Regulatory status Azelaic Acid vs. Benzoyl Peroxide in the EU and US
In the EU, azelaic acid is allowed in cosmetic products without concentration limits, making it easy for brands to formulate and market products across Europe. In the US, azelaic acid is not regulated for cosmetics application and regulated in pharma application as a prescription drug for acne and rosacea. So both in EU and in US markets is it possible to find a wide range of cosmetic formulations with azelaic acid concentrations up to 10–25%.
Meanwhile, benzoyl peroxide, once a staple in acne treatment, is increasingly scrutinized due to its instability, cytotoxic potential, skin sensitization and risk of forming carcinogenic benzene under certain conditions. While its use is banned in cosmetic and medical device applications within the European Union, citing the above safety concerns, it continues to be permitted as an over the counter (OTC) ingredient for acne treatment in the United States.
1 Kucera, K., Zenzola, N., Hudspeth, A., Dubnicka, M., Hinz, W., Bunick, C.G., Dabestani, A., & Light, D.Y. (2024). Benzoyl Peroxide Drug Products Form Benzene. Environmental Health Perspectives, 132(3), 037702. https://doi.org/10.1289/EHP13984
However, this legal allowance may be approaching a turning point. The U.S. Food and Drug Administration (FDA) has initiated a comprehensive evaluation of benzoyl peroxide’s safety, and industry experts anticipate that heightened regulatory restrictions—or even market withdrawal—may soon follow. These developments signal a potentially significant shift in the availability and future viability of benzoyl peroxide-based formulations in the US market
A smarter alternative: why formulators are turning to Azelaic acid over Benzoyl peroxide?
As formulators seek safe, effective alternatives, azelaic acid—particularly the high-purity, 100% bio-based form Azepur99® azelaic acid from Azeco Cosmeceuticals—emerges as a standout solution. Unlike benzoyl peroxide, azelaic acid does not decompose into harmful compounds and maintains a remarkable safety profile. It shows no significant side effects, it has no cytotoxic properties and does not exhibit carcinogenic, mutagenic or reprotoxic (CMR) properties, nor make the skin more sensitive to sunlight.
In cosmetic formulations, azelaic acid offers antimicrobial, anti-inflammatory, comedolytic, and hyperpigmentation reducing properties—making it particularly effective for acne-prone and rosacea-prone sensitive skin. Unlike benzoyl peroxide, which eradicates both harmful and beneficial skin microbiota indiscriminately, azelaic acid assists in normalisation of the skin’s microflora, targeting Propionibacterium acnes and Staphylococcus epidermidis2 while preserving microbial balance.
One of the key advantages of Azepur99® azelaic acid is its self-preserving nature, which simplifies formulation. Its stability profile further sets it apart: while benzoyl peroxide is notoriously unstable, degrading readily to form radicals and potentially harmful by-products (including benzene), azelaic acid remains stable under normal cosmetic processing and storage conditions
2 - Holland, K., & Bojar, R. (1993). Antimicrobial effects of azelaic acid. Journal of Dermatological Treatment, 4(sup1), S8–S11. https://doi.org/10.3109/09546639309082152
Multi-tasking care without compromise
Despite their similarities and proven efficacy in treating acne, azelaic acid is gentler, then the suitable choice for people with sensitive skin. Benzoyl peroxide is known to cause peeling, irritation, and may dry out skin in its attempts to inhibit excess oil. In addition, the skin treated with benzoyl peroxide is more vulnerable to sun damage. Another key difference between azelaic acid and benzoyl peroxide is that azelaic acid promotes the skin’s cell turnover process, triggering collagen production to heal and repair damaged skin. Azelaic acid is also an antioxidant, then able to react with free radicals in the skin.
Benzoyl peroxide, on the other hand, works thanks to the formation of free radicals in the skin and, if used repeatedly, it may create skin changes similar to sun damage.3
Then, azelaic acid offers a compelling alternative to benzoyl peroxide, especially for consumers seeking gentle, multi-tasking, and cosmetically elegant solutions for skin prone to acne, pigmentation, and sensitive skin. Its broad spectrum of benefits, lower irritation risk, and additional advantages such as antioxidant protection and pigment regulation position it as a premium ingredient in modern cosmetic skincare formulations. Azepur99® azelaic acid high purity (≥99%) and European bio-based origin meet clean beauty standards and appeal to environmentally conscious brands.
As regulatory pressures mount and consumer demand for safe, sustainable skincare intensifies, azelaic acid offers a science-backed, skin-kind alternative to benzoyl peroxide—proving that efficacy doesn't have to come at the cost of safety.
References:
- Kucera, K., Zenzola, N., Hudspeth, A., Dubnicka, M., Hinz, W., Bunick, C.G., Dabestani, A., & Light, D.Y. (2024). Benzoyl Peroxide Drug Products Form Benzene. Environmental Health Perspectives, 132(3), 037702. https://doi.org/10.1289/EHP13984
- Holland, K., & Bojar, R. (1993). Antimicrobial effects of azelaic acid. Journal of Dermatological Treatment, 4(sup1), S8–S11. https://doi.org/10.3109/09546639309082152
- Webster, G. (2000), Combination azelaic acid therapy for acne vulgaris, J Am Acad Dermatol; 43(2 Pt3): S47-50. doi: 10.1067/mjd.2000.108318