Natural vs. Synthetic Fragrance

Natural fragrance materials are botanical extracts obtained by approved physical, microbiological or enzymatic methods; synthetic materials are aroma molecules made by controlled chemical processes or isolated from natural sources. Neither origin decides safety or sustainability on its own: safety depends on exposure, concentration and use case, and environmental impact depends on lifecycle. Both are assessed under the same IFRA and RIFM frameworks, and professional perfumery uses both — chosen by what the finished product has to do.

Key Takeaways

• 01Under ISO 9235, a material counts as natural only if it comes from a botanical source and is extracted by an approved method — steam distillation, cold pressing, CO₂ extraction, solvent extraction, or fermentation.
• 02From a toxicology standpoint there is no inherent human health advantage to plant-based ingredients. Safety depends on exposure, concentration and use case.
• 03Natural and synthetic materials are assessed under the same frameworks: IFRA and RIFM evaluate dermal exposure, inhalation exposure, allergen content, phototoxicity and environmental toxicology.
• 04Sustainability depends on impact and lifecycle. Many natural extracts need thousands of pounds of plant matter per kilogram of oil; many modern synthetics are made from upcycled or renewable feedstocks.

• What Are Natural Fragrance Materials?
• What Are Synthetic Fragrance Materials?
• How Do Natural and Synthetic Materials Compare?
• Are Natural Fragrances Safer Than Synthetic?
• Plant-Based or Hybrid: Which Path Fits Your Product?
• Does Natural Mean a Shorter Allergen Declaration?
• Where Do Declared Allergens Actually Come From?
• How Are Fragrance Materials Assessed for Safety?
• Are Natural Ingredients More Sustainable Than Synthetics?

What Are Natural Fragrance Materials?

Natural fragrance ingredients come directly from plants through physical, microbiological, or enzymatic processes. Under ISO 9235, a material is considered “natural” only if it originates from a botanical source and is extracted using approved methods such as:

• Steam distillation
• Cold pressing
• CO₂ extraction
• Solvent extraction (concretes, absolutes)
• Fermentation or enzymatic modification

Examples include essential oils, absolutes, resinoids, CO₂ extracts, and tinctures.

What Are Synthetic Fragrance Materials?

Synthetic fragrance materials are aroma molecules produced through controlled chemical processes or isolated from natural sources. Many are identical to molecules found in nature — others are inspired by it.

Common examples include:

• Linalool (found in lavender)
• Citronellol (found in rose)
• Vanillin (found in vanilla beans)

How Do Natural and Synthetic Materials Compare?

Are Natural Fragrances Safer Than Synthetic?

Modern fragrance creation blends the beauty of natural materials with the precision and sustainability of contemporary aroma chemistry. At Stock Fragrance, we use both 100% plant-based fragrance oils and hybrid natural + man-made formulations depending on the goals of the final product.

This is the foundation of IFRA, RIFM, EU Cosmetics Regulation, and global fragrance safety assessment.

Why plant-based doesn’t automatically mean safer

Natural materials often have:

• High allergen content (citral, limonene, linalool, farnesol, etc.)
• Phototoxic compounds (especially in citrus oils)
• Variation in composition from crop to crop

For example, brands developing hypoallergenic products typically avoid natural materials entirely, since many botanicals naturally contain EU-regulated allergens that cannot be removed.

Why synthetics are essential

Modern aroma molecules are often designed to:

• reduce sensitization risk
• eliminate phototoxicity
• improve biodegradability
• lower environmental footprint
• provide consistency across production cycles

This makes them a responsible choice for many applications — especially for laundry, candles, cleaning products, fine fragrance, or any formula needing stability.

Plant-Based or Hybrid: Which Path Fits Your Product?

Does Natural Mean a Shorter Allergen Declaration?

This is where the two words part company with the label, and it surprises people. The European declarable-allergen list is written by substance. It names molecules. It does not ask where a molecule came from, and it gives no exemption to a material that arrived in the bottle by being pressed out of a peel rather than built in a reactor.

Read our own glossary of named materials with that in mind and the list reads like a catalogue of naturals:

• Limonene — the dominant molecule in citrus peel oils, mostly recovered as a co-product of citrus juice production.
• Linalool — occurs in lavender, coriander and rosewood, and is also made synthetically at scale.
• Citral — the dominant component of lemongrass and litsea cubeba oils.
• Eugenol — the main constituent of clove and cinnamon leaf oils.
• Cinnamal — the main constituent of cinnamon bark oil.
• Coumarin — occurs naturally in tonka bean and hay, though the material used in formulas is normally synthesized.

So the intuition runs backwards as often as it runs true. An all-natural citrus composition can carry a longer declarable list than a synthetic one built to avoid those molecules, simply because limonene and citral are citrus oil. The point is not that naturals are worse. It is that origin is not the variable the label is measuring.

There is a second reason this matters more in 2026 than it did three years ago. The EU sharply expanded the list in 2023 — from roughly two dozen individually declarable allergens to about eighty. New products must comply from 31 July 2026, with existing stock given until 31 July 2028. That expansion applies to naturals and synthetics alike, and because it reaches further down into trace constituents, it tends to catch complex botanical materials first.

The document that answers it for a specific oil is its allergen declaration, not its origin story. Our primer on how that document is read is Fragrance Allergens Explained.

Where Do Declared Allergens Actually Come From?

The expanded EU allergen statement does something most discussions of this question never get to see: for every component it declares, it records how that component got into the oil. There are separate columns for material added to the formula deliberately, for material arriving indirectly from a natural ingredient, and for material arriving indirectly from a synthetic one.

That turns the natural-versus-synthetic argument into something countable. Across the 24 expanded statements Stock Fragrance publishes there are 462 declared component entries. Sorted by which columns carry a figure, they fall out like this:

The row that matters is the third one, taken together with the fourth. 142 of the 462 entries — just over 30 % — carry a figure in both the natural and the synthetic column at once. The same allergen, in the same oil, arrived partly from a botanical ingredient and partly from an aroma chemical. It happens at least once on 21 of the 24 statements.

Which is the measured version of the point this whole page is making. A declaration cannot be sorted into a natural half and a synthetic half, because in roughly a third of cases the molecule is both. Only 15 entries out of 462 — about 3 % — come from a synthetic route and nothing else. Linalool is declared on 23 of the 24 statements, and on 14 of those it arrives by both routes in the same bottle.

A regulator reading that declaration does not care which route the molecule took, and neither does a person with a sensitivity. The limit applies to the molecule.

How Are Fragrance Materials Assessed for Safety?

Whether natural or synthetic, all fragrance materials are evaluated under the same global safety frameworks. IFRA and RIFM assess ingredients based on:

• Dermal exposure
• Inhalation exposure
• Allergen content
• Phototoxicity
• Environmental toxicology

This ensures products remain safe when used as intended. All Stock Fragrance oils come with:

• IFRA 51 Regulatory Data Sheets
• SDS documentation
• Allergen declarations
• Full ingredient disclosure upon request

For details on how to read these documents, see: How to Read an SDS

Are Natural Ingredients More Sustainable Than Synthetics?

A common misconception is that natural materials are more environmentally friendly.

Final Thoughts

The natural-versus-synthetic discussion is often oversimplified. The real question is not which is “better,” but which materials best support responsible, safe, high-performing fragrance creation. At Stock Fragrance, we use both plant-based and modern aroma materials intentionally — based on science, safety, sustainability, and the needs of the final product.

Related reading

More background on materials, documentation and formulation sits in our fragrance oil knowledge center. To smell the range before committing to a formula, the Discovery Set ships individually wrapped paper blotters scented with our oils — the complete set covers the current collection, and a plant-based version covers the ISO 9235 oils only.