Fragrance Diffusers: What Are the Chemical Safety and Regulatory Compliance Challenges?
- 17 hours ago
- 5 min read
Fragrance diffusers, often perceived as wellness or decorative products, are becoming increasingly common in homes: reed diffusers, electric diffusers (plug-in, nebulisers, ultrasonic devices, etc.), sprays, stone diffusers, candles, and more. Their promise is simple: to create a pleasant and relaxing olfactory atmosphere. However, from a regulatory and safety perspective, these products are far from trivial. Whenever they contain a chemical mixture, whether of natural or synthetic origin, intended for release into indoor air, they raise a fundamental question: how can their chemical safety for consumers be ensured?
Even when their function is exclusively fragrance-related, with no sanitising, antimicrobial, or repellent claims, these products may expose consumers to various chemical substances through inhalation, accidental dermal contact during refilling, or even accidental ingestion.
brands, the challenge is therefore not merely aesthetic or marketing-related. It is about demonstrating that the product placed on the market has been properly classified, labelled, and can be used safely under foreseeable conditions of use.
Proper Product Qualification: A Fragrance Diffuser Remains a Chemical Product
In the case of a fragrance diffuser, the product should first and foremost be considered a chemical mixture, sometimes associated with a support or diffusion device.
The fragrance formulation may contain solvents, fragrance compositions, essential oils, allergens, volatile organic compounds (VOCs), or substances presenting physicochemical, toxicological, or environmental hazards. The diffusion system itself, bottle, reeds, cap, refill, or electrical device, also plays a key role and influences the overall safety of the product.
CLP: Classification, Labelling and Packaging of the Fragrance Mixture
The CLP Regulation forms the European foundation for the classification, labelling, and packaging of hazardous substances and mixtures. It requires the hazards of a mixture to be determined before it is placed on the market.
For a fragrance diffuser, this step is essential because it directly determines the information that must appear on the label: hazard pictograms, signal words, hazard statements, precautionary statements, supplier identification, and product identification. The Unique Formula Identifier (UFI) provides the link between the marketed product and the information submitted to Poison Centres. In the event of accidental exposure, it facilitates rapid identification of the mixture composition and supports appropriate medical advice.
REACH and GPSR: From Substance Data to Finished Product Safety
The REACH Regulation is a key source of information for documenting the hazards and risks of substances used in fragrance diffusers. However, it operates on a substance-by-substance basis, and the extent of available data largely depends on manufacturing or import volumes.
From one tonne per year per registrant, a substance subject to registration must be supported by a dossier containing minimum hazard information. From ten tonnes per year onwards, additional requirements apply, including a Chemical Safety Assessment (CSA) and, where certain hazard criteria are met under Article 14(4) of REACH, an exposure assessment and risk characterisation.
For products intended for release into indoor air, this information can help determine whether anticipated consumer exposure remains compatible with available toxicological reference values.
However, REACH alone does not always answer the question of finished product safety. Some substances may be used below registration thresholds, toxicological information may be limited, certain uses may be described too broadly, and available exposure scenarios may not accurately reflect the real conditions of use of a fragrance diffuser, such as diffusion duration, frequency of use, or exposure of sensitive populations.
In such cases, the General Product Safety Regulation (GPSR) acts as a safety net. Since 13 December 2024, every consumer product must be safe under normal or reasonably foreseeable conditions of use (see our related article on the subject).
For a fragrance diffuser, this assessment should be based on a comprehensive chemical safety approach applied to the finished product, taking into account both the hazards associated with the substances contained in the formulation and the exposure resulting from the product’s normal and reasonably foreseeable conditions of use (see our related article on the subject).
The GPSR places responsibility on the economic operator placing the product on the market to demonstrate that the fragrance diffuser does not present an unacceptable chemical risk to consumers under normal and reasonably foreseeable conditions of use.
The Complex Case of Essential Oils
The relationship between REACH and GPSR is particularly important when a formulation contains essential oils. An essential oil is a complex natural substance composed of numerous constituents whose proportions may vary depending on plant species, geographical origin, cultivation conditions, extraction method, and plant part used. Its composition is not always fully characterised, and the frequent lack of toxicological data can make hazard and risk assessment particularly challenging.
In this context, the GPSR plays a crucial role by enabling a broader assessment than that based solely on information available under REACH. It allows a more refined evaluation of the risks associated with the presence of essential oils in the finished product.
When available information is limited, it becomes necessary to examine the composition of the essential oil more closely, identify relevant constituents, and assess the robustness of the toxicological reference values used for risk characterisation.
Essential oils are widely used in fragrance diffusers and are often marketed based on their natural origin. However, natural origin does not necessarily simplify toxicological assessment. On the contrary, it may make it significantly more complex.
This raises an important methodological question: should an essential oil be assessed as a whole substance, or should the assessment focus on its major constituents and identified substances of concern, even when present at low concentrations?
The answer is critical when establishing a representative toxicological reference value. Failure to identify certain constituents and their associated hazards limits the overall representativeness of the available data. Furthermore, toxicological information is often insufficient, both for the essential oil itself and for some of its identified constituents.
In the absence of fully established assessment methodologies for these complex natural substances, defining a robust and representative toxicological reference value may prove particularly challenging.
How Can the Compliance and Safety of a Fragrance Diffuser Be Ensured?
Compliance should not be viewed solely through the lens of labelling requirements or the natural origin of ingredients. Rather, it requires a robust chemical safety strategy that combines the use of relevant data available under REACH with a finished-product risk assessment under the GPSR whenever necessary. This involves identifying the substances present in the product, evaluating their hazards, classifying the mixture correctly, fulfilling Poison Centre notification obligations where applicable, selecting appropriate toxicological reference values for the relevant exposure routes, documenting the intended conditions of use, and ensuring that any potential risks are adequately controlled through qualitative and/or quantitative risk assessment and suitable risk management measures.
Auteure : Anna Chelle, Toxicologue et Responsable du service Évaluation des risques chimiques et sécurité
