The European Union has launched a new safety assessment concerning cuminaldehyde and p-cymene, two fragrance-related substances that may occur naturally in essential oils used in cosmetic products.
The European Commission has requested the Scientific Committee on Consumer Safety (SCCS) to evaluate whether cuminaldehyde and p-cymene can be safely used in cosmetics.
Both substances may occur naturally as constituents of essential oils and natural complex substances used in fragrances, skincare products and other personal care formulations. As a result, the outcome of the SCCS assessments could have implications extending beyond the individual substances and potentially affect cosmetic formulations containing certain essential oils.
The SCCS mandates for both substances were approved on 29 July 2026.
What Is the EU Cosmetics Industry Requesting?
The EU cosmetics industry has indicated that it does not intend to defend the use of cuminaldehyde or p-cymene as intentionally added standalone cosmetic ingredients.
Instead, the industry is seeking to maintain their use when they occur naturally as constituents of essential oils, subject to maximum concentrations considered safe by the SCCS.
This distinction is particularly important because the substances cannot necessarily be selectively removed from the relevant botanical raw materials.
For example:
- Cuminaldehyde occurs naturally in cumin oil and other natural complex substances.
- p-Cymene may be present in thyme, oregano and cumin oils.
Therefore, an unfavourable regulatory outcome could potentially affect a much wider range of formulations containing these essential oils rather than only products in which cuminaldehyde or p-cymene are deliberately added as individual ingredients.
Why Are Cuminaldehyde and p-Cymene Under Review?
The SCCS reviews follow developments under the EU’s chemicals classification framework.
Within the European Chemicals Agency (ECHA) process, reproductive toxicity classifications have been proposed for p-cymene and related substances, including cuminaldehyde. ECHA documentation includes a proposed classification of Reproductive Toxicity Category 1B – Repr. 1B, H360FD for p-cymene.
A Repr. 1B classification indicates that a substance is presumed to be toxic to human reproduction, primarily on the basis of evidence obtained from animal studies.
Such a classification is particularly significant for the cosmetics industry because substances classified as carcinogenic, mutagenic or toxic to reproduction (CMR substances) under the CLP Regulation are subject to specific requirements under the EU Cosmetics Regulation.
What Would a Repr. 1B Classification Mean for Cosmetics?
Article 15 of Regulation (EC) No 1223/2009 on cosmetic products sets out the rules applying to substances classified as CMR under the EU CLP Regulation.
Substances classified as CMR Category 1A or 1B are generally prohibited from use in cosmetic products unless specific exemption conditions are met.
EU legislation also provides for such substances to be reflected in Annex II of the Cosmetics Regulation, which contains substances prohibited in cosmetic products.
Importantly, however, the current SCCS review does not mean that cuminaldehyde or p-cymene are already subject to a confirmed cosmetics ban.
The ongoing scientific assessment and subsequent EU regulatory process will determine whether restrictions, maximum concentrations or other risk management measures are required.
Can CMR Category 1A or 1B Substances Be Exempted?
Article 15(2) of the EU Cosmetics Regulation provides a specific exemption mechanism that may allow a Category 1A or 1B CMR substance to continue to be used in cosmetics where all applicable conditions are fulfilled.
These include requirements that the substance:
- complies with relevant EU food safety requirements;
- has no suitable alternative available, supported by appropriate justification;
- is intended for use in a specific product category with a known exposure profile; and
- is considered safe by the SCCS, taking into account aggregate exposure from cosmetics and other relevant sources.
This mechanism may be particularly relevant where a substance occurs naturally as part of an essential oil or other Natural Complex Substance (NCS).
Why Could Essential Oils Be Affected?
The regulatory significance of the cuminaldehyde and p-cymene assessments goes beyond the two individual molecules.
Both may naturally occur in essential oils used as botanical cosmetic ingredients. Consequently, a restrictive regulatory outcome could potentially affect formulations containing:
- cumin oil,
- thyme oil,
- oregano oil,
- natural fragrance blends,
- botanical skincare ingredients,
- essential oil-based personal care products
For formulators, removing a particular constituent from a natural oil is not always technically feasible. In some cases, compliance with a future concentration limit could therefore require reducing, replacing or completely removing the essential oil from the formulation.
What Should Cosmetic Companies Consider?
Although no final prohibition or restriction has yet been adopted, companies operating in the EU cosmetics market may wish to begin assessing potential exposure.
Relevant steps may include:
- identifying raw materials containing cuminaldehyde or p-cymene;
- reviewing formulations containing cumin, thyme or oregano oils;
- checking essential oil specifications and compositional data;
- requesting concentration information from raw material suppliers;
- evaluating potential reformulation scenarios;
- monitoring SCCS opinions and the relevant CLP classification process.
Early assessment may help manufacturers and Responsible Persons anticipate possible future compliance requirements.
When Will the SCCS Opinions Be Published?
The SCCS has been given approximately nine months to complete each assessment. Based on the mandates adopted in July 2026, the scientific opinions are therefore expected around April 2027.
At this stage, there is no confirmed EU cosmetics ban or final maximum concentration for either cuminaldehyde or p-cymene.
Companies using essential oils or natural fragrance ingredients should therefore continue monitoring the SCCS assessments and subsequent regulatory developments.