Fragrance Oils vs. Essential Oils: What’s Really in Your Soap’s Scent?
When you pick up a bar of soap and breathe in its scent—whether it’s fresh lavender, warm vanilla, or citrus zest—you’re experiencing one of the most important ingredients in soapmaking: fragrance. But what’s actually responsible for that scent? Is it essential oils, synthetic fragrance, or something else entirely?
The truth is more complex than “natural vs. artificial.” Both essential oils and fragrance oils can contain allergens, and both are regulated to ensure safe use by organizations like the International Fragrance Association (IFRA). In this post, we’ll break down the science of scent, explore common allergens, and explain how makers like The Clean Chemist choose safe, sustainable, and skin-friendly options for every bar.
What are Essential Oils?
Essential oils are concentrated, complex mixtures of volatile aromatic compounds created through natural chemical processes in plants. While “volatile substances” sounds a little scary, this just means that they’re substances that evaporate easily. A typical essential oil will have more than 90 distinct volatile compounds — terpenes, esters, ethers, aldehydes, and more!
Essential oils are typically extracted using one of three methods:
Steam distillation: Steam passes through crushed plant material, carrying volatile compounds into a cooling chamber, where they condense into liquid essential oil.
Where botany meets chemistry—steam distillation extracts essential oils by harnessing heat, vapor, and a little molecular magic.
Solvent extraction: Solvents like carbon dioxide, alcohol, or hexane, are used to extract the volatile substances from the plant mixture at lower temperatures, preserving the oil’s natural molecular structures.
Supercritical style—CO₂ under pressure dives into plants and comes out smelling like science, no heat required!
Cold pressing: Often used for citrus peels, this method mechanically presses oils out without heat, relying solely on pressure.
What about Fragrance Oils?
Fragrance oils are also concentrated, complex mixtures of volatile aromatic substances. However, instead of these volatile aromatic substances being only from plants, fragrance oils are made from a combination of essential oils, animal products (musk, ambergris, civet, and castoreum) and synthetic oils.
Synthetic oils are made by specialized chemists called perfumers. Perfumers bring their extensive knowledge of chemistry, raw materials, and consumer preferences to their work. They blend essential oils, lab-created aromas, and resins to create complex scent profiles.
Just like essential oils, the volatile substances in fragrance oils are created first by chemical reactions then isolated using steam distillation and solvent extraction. Once the components are created and isolated, they are then mixed by the perfumer to create a complete fragrance.
A single fragrance oil can be made from over 80 different essential oils, synthetic oils, and animal products.
Natural vs. Synthetic: Which is Safer?
It’s easy to assume that “natural” always means safer — but when it comes to fragrance, that’s not always the case. Essential oils, though plant-based, are highly concentrated chemical mixtures that can include known allergens like limonene, linalool, cinnamaldehyde, benzyl alcohol, and citronellal.
Synthetic fragrance oils, while lab-made, are often formulated to avoid common allergens and are rigorously tested. Both essential and synthetic oils are subject to IFRA guidelines, which regulate their use in personal care products.
So while essential oils are plant-based, they aren’t automatically non-toxic. And just because a fragrance is synthetic doesn’t mean it’s unsafe.
Hidden Irritants: More on Allergens
Whether derived from nature or synthesized in a lab, many fragrance components can cause irritation or allergic reactions. These allergens are usually naturally occurring compounds within essential oils or are part of synthetic blends.
More than 1 in 10 people are allergic to substances found in fragrances.
Common fragrance allergens include:
Linalool (in lavender, citrus, mint)
Limonene (in citrus peels, dill, bergamot)
Cinnamyl alcohol & Cinnamal (in cinnamon oils)
Eugenol (in clove, nutmeg, cinnamon)
Oakmoss and tree moss extracts
Anisyl alcohol (in vanilla and anise oils)
Amylcinnamyl alcohol (synthetic)
To protect consumers, the IFRA mandates disclosure of 26 common allergens on product labels if their concentrations exceed certain thresholds.
Our Approach to Allergens
At The Clean Chemist, transparency and safety are our top priorities. We comply fully with IFRA guidelines and clearly label all fragrance ingredients. For sensitive customers, we offer unscented options and custom formulas to meet individual needs. Every product is designed with skin health in mind—because clean chemistry means radiant skin.
