ECHA Issues New Restrictions on HOMONOPAL (Pinoacetaldehyde) – CAS 33885-51-7

A Floral Aldehyde Under Regulatory Scrutiny

HOMONOPAL, also known as Pinoacetaldehyde, is a synthetic aromatic aldehyde commonly used in fragrance compositions. Its CAS number is 33885-51-7. Known for its green, floral, and slightly aldehydic scent, this compound imparts freshness and lift to perfume accords, particularly in fine fragrances, personal care products, and cleaning formulations.

Industries Impacted

HOMONOPAL is used across a wide range of sectors:

• Cosmetics and personal care, including perfumes, shampoos, lotions

• Household cleaning agents

• Industrial fragrance applications

Its broad application stems from both its olfactory profile and its performance in complex fragrance matrices.

New Regulatory Developments from ECHA

In April 2025, the European Chemicals Agency (ECHA) published a new Assessment of Regulatory Needs (ARN) for Pinoacetaldehyde. This document significantly shifts the regulatory landscape for this fragrance ingredient, highlighting serious human health and environmental concerns.

ECHA concludes the substance presents:

• Known or potential hazard for reproductive toxicity

• Known or potential hazard for skin sensitisation

• Known or potential hazard for aquatic toxicity

Based on this assessment, ECHA outlines the following regulatory actions:

• "Harmonised classification as Reprotoxic category 1B."

• "Potential restriction: Harmonised classification as Repr. 1B would lead to generic restriction of the substance(s) in consumer mixtures by means of restriction entry 30."

• "The harmonised classification as Repr. 1B may trigger regulatory action under the Cosmetic Products Regulation and render the substance unacceptable as a co-formulant in biocidal products."

The assessment also notes that HOMONOPAL is widely used in professional settings, often with low levels of operational controls and risk management:

• “Restriction of professional uses is preferred over authorisation as it is considered to be more efficient and effective to introduce controls at the level of placing on the market rather than at the level of uses.”

• "Frequent exposures with a long duration" are also highlighted, particularly concerning for vulnerable worker populations.

Implications for the Cosmetics Industry

The harmonised classification as Reprotoxic Category 1B has direct implications for cosmetic uses. Under the Cosmetic Products Regulation (EC) No 1223/2009, substances classified as Repr. 1B are generally prohibited unless explicitly exempted by the European Commission.

In practical terms, this could mean:

• Prohibition of HOMONOPAL in consumer cosmetics

• Reformulation pressures on fragrance suppliers

• Loss of functionality in certain perfume accords

If the restriction under Annex XVII, entry 30 of REACH is adopted, it will also mean a generic restriction in consumer mixtures, including many non-cosmetic fragrance applications.

Conclusion

The regulatory future of HOMONOPAL is now at a critical juncture. While still legally used today, the proposed harmonised classification and restrictions may lead to its complete phase-out in consumer products, including cosmetics. Formulators, regulatory teams, and risk assessors should begin preparing substitution strategies and consider the toxicological profile of alternatives.

This case exemplifies the increasing scrutiny on fragrance ingredients and the importance of proactively managing substances with potential reproductive and environmental hazards.

Link to the ECHA assessment