n-Hexane: An Omnipresent Solvent, Soon to Be Classified as a “Substance of Very High Concern”?

n-Hexane (CAS No. 110-54-3) is a volatile aliphatic hydrocarbon derived from petroleum distillation. Used as a solvent, it plays a key role in several sectors: 

• Food industry: extraction of vegetable oils (soy, rapeseed, sunflower), flavors, and proteins. 

• Cosmetics and perfumery: obtaining absolutes, essential oils, and pure plant extracts. 

Its popularity is based on its efficiency, high yield, and low cost. However, this solvent requires strict purification to limit residues and protect exposed workers (ANSES).  

Long largely unknown to the general public, its use is now attracting attention. The press (Le Point) recently highlighted that it could indirectly be present in certain food products. Once metabolized, n-hexane is converted into 2,5-hexanedione, a molecule capable of accumulating in the brain and causing neurological effects (Fiche toxicologique n°113 - Edition Juin 2025).  

The ECHA Proposal: Toward Inclusion on the SVHC List 

In February 2025, Slovenia proposed to ECHA (European Chemicals Agency) that n-hexane be classified as a Substance of Very High Concern (SVHC) due to its neurotoxicity. The public consultation, opened in August 2025, will close on October 16, 2025. 

This classification is based on Article 57(f) of the REACH Regulation (EC No. 1907/2006).

The candidate SVHC list already includes over 240 concerning substances (carcinogens, reproductive toxins, endocrine disruptors, etc.). Inclusion triggers information obligations and can lead to authorizations or usage restrictions. 

Implications for the Cosmetic and Food Industries, and for Consumers 

• Transparency and labeling: obligation to inform when a product contains more than 0.1%. 

• Search for alternatives: adoption of safer processes (supercritical CO₂, “green” solvents). 

• Costs and reformulations: adaptation of processes, investments, and potential increase in final product price. 

• Health and public perception: better protection and transparency for consumers, but possible increased concern reported by media. 

• Regulatory pressure and certifications: organic certifications and certain markets will likely require its absence, accelerating the transition to other techniques. 

This trend is already encouraging the development of solvent-free processes, such as the EcoXtract® approach. 

Consideration in Cosmetic Products 

In cosmetics, n-hexane may remain as trace residues after ingredient extraction. At these levels, the risks are considered negligible for consumers. European Cosmetic Regulation No. 1223/2009 requires safety assessors to check for these impurities in their reports. 

Classified as CMR (Repro cat.2, H361f), n-hexane is prohibited as an ingredient in cosmetic products. As in the pharmaceutical sector (ICH Q3C (R8)), it is only tolerated as a residual impurity at strictly limited concentrations. Its neurotoxic effects, severe at high doses, are known and controlled through exposure thresholds. Therefore, the presence of traces does not pose a danger to the end user. 

Ensuring Safety and Anticipating Regulatory Changes 

For manufacturers, having a detailed toxicological profile of each substance is essential to secure formulations and anticipate regulatory developments. Potential inclusion of n-hexane on the SVHC list would mark an important step and could accelerate the transition to more sustainable alternatives. 

In the context of cosmetic regulations, having a detailed toxicological profile helps professionals anticipate and secure their formulations. 

➡️ To explore the complete profile of this substance, visit our dedicated page: 👉 https://www.cehtra.com/cosmetick  

And check out the associated LinkedIn post for a concise overview.