Economic Analysis of the Impacts of the Chemicals Strategy for Sustainability Mixture Assessment Factor (MAF)

The idea of a ​‘Mixture Assessment Factor’ (MAF) was first put forward in the Chemicals Strategy for Sustainability (CSS) in 2020. It included a commitment to assess how best to introduce one (or several) MAFs into the chemical safety assessment of substances under REACH, to address the combined exposure to chemicals.

Since then, EU policy priorities have shifted towards competitiveness and simplification, with the Clean Industrial Deal and the Action Plan for the Chemicals Industry, both published in 2025. The MAF remains under discussion in the context of targeted adjustments to REACH.

Today, the safety of an individual substance is demonstrated by comparing exposure levels against no-effect thresholds. A MAF would apply an additional, generic safety margin to these thresholds, to account for combined exposure to multiple substances from multiple sources. Its size and how it would be applied have not been defined. Yet REACH already relies on conservative methodologies that cover substances on their own and in mixtures, across their entire life cycle, and that capture potential combined exposures.

A fragrance mixture typically combines dozens to hundreds of ingredients, in most cases at less than one percent of the final product.

To help inform the discussions, IFRA commissioned a study to examine what the introduction of a generic MAF could mean in practice for the fragrance industry.

The analysis finds that meeting a MAF-adjusted threshold would typically require fragrance manufacturers to combine several types of action, from refining exposure assessments and generating new safety data to introducing additional risk management measures and, in some cases, withdrawing or substituting certain uses. Even where such measures are taken, the study estimates that a substantial share of current business activity could no longer be supported. This would affect turnover, employment and value added across the EU fragrance value chain, as well as the sector’s competitiveness and supply chains.

The report supports IFRA’s opposition to a generic, one-size-fits-all MAF.

Combined exposure is a complex matter that cannot be addressed through such a simple solution, for which there is no scientific justification. IFRA believes that any additional MAF should be based on robust scientific assessment and be subject to an impact assessment by the authorities, taking into account existing sector-specific risk management measures.

Scientific assessments, including by experts from the German Federal Institute for Risk Assessment (BfR)¹, have found no general evidence that combined exposure to multiple substances inherently increases toxicity compared to individual exposures.

These findings are reflected in IFRA’s position on REACH (June 2026), available on a separate webpage.

¹ Herzler, M., Marx-Stoelting, P., Pirow, R. et al. The ​“EU chemicals strategy for sustainability” questions regulatory toxicology as we know it: is it all rooted in sound scientific evidence?. Arch Toxicol 95, 2589 – 2601 (2021). https://​doi​.org/​1​0​.​1​0​0​7​/​s​0​0​2​0​4-021 – 03091‑3: ​“the impression that people exposed to mixtures of chemicals will always experience higher toxicity than when exposed to the same chemicals alone is not reflected in the current state of science or that of previous regulatory assessments.”