Fragrance Oil Versus Essential Oil on Your Ingredient List

A maker emailed us asking why her supplier's lavender fragrance oil needed a totally different ingredient declaration than the lavender essential oil she used in the same product line. Fair question, and it trips up a lot of people because both smell like lavender and both get sold as "lavender oil" on the supplier's invoice. What they are, chemically, is not remotely the same.

Essential oil: one plant, one INCI, usually one CAS

A true essential oil is extracted directly from a plant, typically by steam distillation, and it declares on your ingredient list as a single INCI entry tied to the botanical source. Lavender essential oil is Lavandula Angustifolia Oil. Tea tree is Melaleuca Alternifolia Leaf Oil. Peppermint is Mentha Piperita Oil.

Each of those has its own CAS number, or in some cases more than one CAS number depending on the extraction method or chemotype, since CAS numbers track specific chemical registrations rather than plant names. What you're declaring is the whole oil as it comes off the still, a complex natural mixture that nonetheless gets one line on your ingredient list.

The regulatory catch: that single oil is not chemically simple. Lavender oil naturally contains linalool, linalyl acetate, and smaller amounts of other constituents. Some of those constituents are fragrance allergens in their own right, so even though you're listing "Lavandula Angustifolia Oil" as one INCI, you may still owe an allergen declaration for what's inside it once it crosses the disclosure threshold.

Fragrance oil: a blend that hides behind one word

A synthetic or compounded fragrance oil is a different animal. It's a mixture, often dozens of individual aroma chemicals, put together by a fragrance house to smell like lavender, or vanilla, or "ocean breeze," without necessarily containing much or any of the actual plant material.

On an ingredient list, this typically declares as Parfum (or Fragrance), a single umbrella INCI term that lets the fragrance house protect its formula as proprietary. The trade name, "Lavender Dreams Fragrance Oil #4471," never appears on your filing. It gets mapped to Parfum.

But the umbrella term doesn't exempt the individual allergens hiding inside it. If the fragrance house's blend contains linalool, limonene, coumarin, or any of the other declarable allergens above the disclosure threshold, those need to be pulled out and listed individually alongside the Parfum entry, not buried inside it.

Side by side

Source	Typical INCI declaration	CAS situation	Allergen exposure
Essential oil (e.g. lavender)	Named botanical oil (Lavandula Angustifolia Oil)	Usually one CAS, sometimes more than one	Allergens naturally present, still need individual disclosure above threshold
Fragrance oil / synthetic blend	Parfum / Fragrance	Not applicable to the blend as a whole; individual aroma chemicals inside have their own CAS numbers	Allergens are compounded ingredients, supplier must disclose which are present and at what level
Fragrance oil with natural isolates	Parfum, sometimes with named naturals declared separately	Depends on formulation	Same disclosure obligation

Where people get this wrong

The most common mistake I see is someone taking a supplier's "fragrance oil" and declaring it with a botanical INCI name because the product name says "rose" or "lavender." If the supplier's documentation calls it a fragrance oil, parfum compound, or aroma blend, you need their allergen breakdown to file correctly. You cannot guess the allergen content from the scent name alone. Ask your supplier for either a full ingredient disclosure or, at minimum, an allergen statement listing which of the declarable allergens are present and above what percentage.

The reverse mistake also happens: treating a real essential oil as if it needs no further breakdown at all because "it's natural." Natural doesn't mean allergen-free. Linalool, geraniol, citronellol, eugenol, and limonene are naturally occurring in dozens of common essential oils, and Canada's fragrance allergen disclosure rules apply regardless of whether the allergen arrived via a lab or a lavender field.

The practical fix

Get supplier documentation for every scent ingredient before you file, not after. For essential oils, that means a certificate of analysis or a spec sheet confirming the botanical source and, ideally, a breakdown of major constituents. For fragrance oils, that means an allergen disclosure statement from the fragrance house, since you as the brand owner are the one accountable for what's on the CNF and the label, not the supplier.

This is one of the fiddlier parts of putting a filing together by hand, matching a shelf full of trade-named oils back to the right INCI and pulling out every allergen that needs its own line. Cosmetic Comply does exactly that matching, oil by oil, and flags anything that needs a supplier follow-up before the filing goes out.