Following the France Inter programme “Le Mag de la vie quotidienne” broadcast on 20 October 2025, home fragrances (scented candles, incense, diffusers, room sprays) are regularly questioned regarding their emissions of volatile organic compounds (VOCs) and their potential impacts on indoor air quality.
These concerns are legitimate. However, when it comes to home fragrances, the key question is not “natural or synthetic?”, but rather: what hazard and what level of exposure does the finished product represent under normal and reasonably foreseeable conditions of use?
Can the toxicity of a home fragrance be assessed based on the origin of its ingredients?
Natural or synthetic origin: a false safety criterion
A widely held belief is that a home fragrance would be less concerning when formulated from natural raw materials (the same belief also exists for wax). This approach is nevertheless scientifically unfounded.
Toxicity cannot be inferred from the origin of substances. A molecule remains a molecule, regardless of its origin. Some natural substances present severe toxicological profiles (irritation, sensitisation, specific toxicity), while synthetic substances can be controlled and safe at the concentrations used.
Hazard is not risk
It is essential to distinguish between:
- hazard, which corresponds to the intrinsic properties of a substance;
- risk, which depends on actual exposure to that substance under the conditions of use of the product.
This distinction is fundamental to understanding why the origin of ingredients alone is not sufficient to characterise the safety of a home fragrance.
VOC emissions: highly variable levels depending on products and uses
Significant differences between product categories
VOC emissions and the associated exposure levels vary greatly depending on the category of home fragrance:
- scented candles,
- incense,
- electric diffusers,
- room sprays,
- reed diffusers.
Each category relies on a different diffusion mode (combustion, evaporation, spraying), resulting in distinct emission profiles.
…but also within the same category
It is misleading to generalise within a single product family. Two scented candles, for example, may present very different VOC emission levels depending on multiple parameters:
- the fragrance formulation,
- the nature and proportion of substances,
- the wax used,
- the size of the candle,
- the burning duration.
Thus, classifying a home fragrance as “more or less toxic” solely on the basis of its category has limited relevance: the analysis must be carried out at the level of the finished product.
Why are such differences in emissions observed?
The key role of components and their interactions
The differences observed between products are largely due to:
- the individual substances present in the formulation,
- the interactions between these substances during combustion or diffusion.
Certain reactions may generate by-products whose toxicological profile differs from that of the initial substances, which justifies a cautious, data-driven approach.
The importance of use conditions
Beyond formulation, use-related factors strongly influence exposure:
- product size,
- diffusion mode,
- duration and frequency of emission,
- room volume,
- air renewal.
A home fragrance used occasionally in a well-ventilated room does not generate the same exposure as a product diffused continuously in a confined space.
Naturalness: why it is not a guarantee of safety
Essential oils: natural but not harmless
Essential oils are often perceived as reassuring because they are natural. However, their natural origin does not imply safety.
Certain essential oils are:
- irritating,
- sensitising,
- neurotoxic,
- or toxic by inhalation at certain doses.
Combustion: increased vigilance
Potential risk may be increased when odorant substances are burned (incense, candles, oil burners). Combustion can modify chemical composition and generate secondary substances that may be of concern.
Thus, a product claimed to be “100% natural” may, depending on formulation and conditions of use, present a higher level of risk than a product formulated with rigorously assessed synthetic substances.
How can the safety of a home fragrance be assessed?
A hazard- and exposure-based approach
The only scientifically robust way to assess the safety of a home fragrance is through a health risk assessment combining:
- the hazard of the substances present,
- the actual exposure linked to the finished product and its use (representative use scenarios).
This approach corresponds to the methodological frameworks used in regulatory assessments.
Assessing the finished product, not isolated ingredients
It is essential to emphasise that this assessment focuses on the finished product as used by the consumer, and not on ingredients taken in isolation or out of context.
It is this global view that makes it possible to objectively conclude on the actual level of risk.
Risk assessment: what is it used for in practice?
Risk assessment is not only used to conclude on product safety. It also makes it possible to define proportionate risk management measures, such as:
- a maximum burning or diffusion duration,
- a recommended minimum room volume,
- ventilation recommendations,
- specific conditions of use (e.g. frequency, combined uses).
These measures help control exposure and ensure safe use, while providing clear and proportionate information.
Regulatory compliance: a key issue for economic operators
Regulation (EU) 2023/988 on general product safety requires economic operators to place on the market only products that do not present an unacceptable risk to consumer health and safety.
In this context, risk assessment applied to home fragrances constitutes an approach that is:
- tailored,
- scientifically grounded,
- essential for responsible market placement.
It makes it possible to move beyond common misconceptions and to address safety with rigour and objectivity.
Conclusion: moving beyond shortcuts between naturalness, origin, and toxicity
Media debates around home fragrances help raise awareness, but they must avoid shortcuts between naturalness, origin of materials, and toxicity.
The reality is more complex: the safety of a home fragrance is not assumed, it is assessed.
Only a health risk assessment based on hazard and exposure makes it possible to conclude on the absence of unacceptable risk under defined conditions of use, while meeting European regulatory requirements.
FAQ: frequently asked questions about home fragrances
Is a “natural” home fragrance necessarily safer?
No. Origin alone does not allow conclusions to be drawn: risk depends on hazard and exposure.
Are VOC emissions the same for all diffusers and candles?
No. They vary greatly depending on formulation, diffusion mode, and conditions of use.
Why is combustion a key point of vigilance?
Because it can lead to the formation of secondary substances and modify emission profiles.
What is the right approach to conclude on product safety?
A health risk assessment of the finished product, based on representative use scenarios.
Need support with the compliance of your home fragrances?
EcoMundo supports brands, manufacturers, and distributors in risk assessment, risk management, and regulatory compliance of home fragrance products placed on the European market.
Would you like to secure your market placement or structure your safety demonstration?
Contact EcoMundo for tailored support (risk assessment, scientific justification, regulatory requirements, and associated documentation).
Following the France Inter programme “Le Mag de la vie quotidienne” broadcast on 20 October 2025, home fragrances (scented candles, incense, diffusers, room sprays) are regularly questioned regarding their emissions of volatile organic compounds (VOCs) and their potential impacts on indoor air quality.
These concerns are legitimate. However, when it comes to home fragrances, the key question is not “natural or synthetic?”, but rather: what hazard and what level of exposure does the finished product represent under normal and reasonably foreseeable conditions of use?
Can the toxicity of a home fragrance be assessed based on the origin of its ingredients?
Natural or synthetic origin: a false safety criterion
A widely held belief is that a home fragrance would be less concerning when formulated from natural raw materials (the same belief also exists for wax). This approach is nevertheless scientifically unfounded.
Toxicity cannot be inferred from the origin of substances. A molecule remains a molecule, regardless of its origin. Some natural substances present severe toxicological profiles (irritation, sensitisation, specific toxicity), while synthetic substances can be controlled and safe at the concentrations used.
Hazard is not risk
It is essential to distinguish between:
- hazard, which corresponds to the intrinsic properties of a substance;
- risk, which depends on actual exposure to that substance under the conditions of use of the product.
This distinction is fundamental to understanding why the origin of ingredients alone is not sufficient to characterise the safety of a home fragrance.
VOC emissions: highly variable levels depending on products and uses
Significant differences between product categories
VOC emissions and the associated exposure levels vary greatly depending on the category of home fragrance:
- scented candles,
- incense,
- electric diffusers,
- room sprays,
- reed diffusers.
Each category relies on a different diffusion mode (combustion, evaporation, spraying), resulting in distinct emission profiles.
…but also within the same category
It is misleading to generalise within a single product family. Two scented candles, for example, may present very different VOC emission levels depending on multiple parameters:
- the fragrance formulation,
- the nature and proportion of substances,
- the wax used,
- the size of the candle,
- the burning duration.
Thus, classifying a home fragrance as “more or less toxic” solely on the basis of its category has limited relevance: the analysis must be carried out at the level of the finished product.
Why are such differences in emissions observed?
The key role of components and their interactions
The differences observed between products are largely due to:
- the individual substances present in the formulation,
- the interactions between these substances during combustion or diffusion.
Certain reactions may generate by-products whose toxicological profile differs from that of the initial substances, which justifies a cautious, data-driven approach.
The importance of use conditions
Beyond formulation, use-related factors strongly influence exposure:
- product size,
- diffusion mode,
- duration and frequency of emission,
- room volume,
- air renewal.
A home fragrance used occasionally in a well-ventilated room does not generate the same exposure as a product diffused continuously in a confined space.
Naturalness: why it is not a guarantee of safety
Essential oils: natural but not harmless
Essential oils are often perceived as reassuring because they are natural. However, their natural origin does not imply safety.
Certain essential oils are:
- irritating,
- sensitising,
- neurotoxic,
- or toxic by inhalation at certain doses.
Combustion: increased vigilance
Potential risk may be increased when odorant substances are burned (incense, candles, oil burners). Combustion can modify chemical composition and generate secondary substances that may be of concern.
Thus, a product claimed to be “100% natural” may, depending on formulation and conditions of use, present a higher level of risk than a product formulated with rigorously assessed synthetic substances.
How can the safety of a home fragrance be assessed?
A hazard- and exposure-based approach
The only scientifically robust way to assess the safety of a home fragrance is through a health risk assessment combining:
- the hazard of the substances present,
- the actual exposure linked to the finished product and its use (representative use scenarios).
This approach corresponds to the methodological frameworks used in regulatory assessments.
Assessing the finished product, not isolated ingredients
It is essential to emphasise that this assessment focuses on the finished product as used by the consumer, and not on ingredients taken in isolation or out of context.
It is this global view that makes it possible to objectively conclude on the actual level of risk.
Risk assessment: what is it used for in practice?
Risk assessment is not only used to conclude on product safety. It also makes it possible to define proportionate risk management measures, such as:
- a maximum burning or diffusion duration,
- a recommended minimum room volume,
- ventilation recommendations,
- specific conditions of use (e.g. frequency, combined uses).
These measures help control exposure and ensure safe use, while providing clear and proportionate information.
Regulatory compliance: a key issue for economic operators
Regulation (EU) 2023/988 on general product safety requires economic operators to place on the market only products that do not present an unacceptable risk to consumer health and safety.
In this context, risk assessment applied to home fragrances constitutes an approach that is:
- tailored,
- scientifically grounded,
- essential for responsible market placement.
It makes it possible to move beyond common misconceptions and to address safety with rigour and objectivity.
Conclusion: moving beyond shortcuts between naturalness, origin, and toxicity
Media debates around home fragrances help raise awareness, but they must avoid shortcuts between naturalness, origin of materials, and toxicity.
The reality is more complex: the safety of a home fragrance is not assumed, it is assessed.
Only a health risk assessment based on hazard and exposure makes it possible to conclude on the absence of unacceptable risk under defined conditions of use, while meeting European regulatory requirements.
FAQ: frequently asked questions about home fragrances
Is a “natural” home fragrance necessarily safer?
No. Origin alone does not allow conclusions to be drawn: risk depends on hazard and exposure.
Are VOC emissions the same for all diffusers and candles?
No. They vary greatly depending on formulation, diffusion mode, and conditions of use.
Why is combustion a key point of vigilance?
Because it can lead to the formation of secondary substances and modify emission profiles.
What is the right approach to conclude on product safety?
A health risk assessment of the finished product, based on representative use scenarios.
Need support with the compliance of your home fragrances?
EcoMundo supports brands, manufacturers, and distributors in risk assessment, risk management, and regulatory compliance of home fragrance products placed on the European market.
Would you like to secure your market placement or structure your safety demonstration?
Contact EcoMundo for tailored support (risk assessment, scientific justification, regulatory requirements, and associated documentation).
