Percent in the Fragrance vs Percent in the Product

I have watched this exact mistake happen enough times that I can predict it before someone finishes their sentence. A maker tells me "the fragrance oil supplier says Linalool is at 2 percent, so I'm fine, that's way under the threshold." Then I ask how much of that fragrance oil is actually in the finished lotion, and there is a pause.

The two numbers that get conflated

There are two completely different percentages in play whenever you are dealing with a fragrance or essential oil blend, and disclosure thresholds only care about one of them.

1. Percent within the fragrance itself. This is what your fragrance house or essential oil supplier gives you on their documentation, something like "this fragrance blend contains 2% Linalool." It describes the composition of the fragrance material as a standalone substance.

2. Percent within the finished product. This is the number that actually matters for disclosure, because thresholds are set against the finished product a consumer applies to their skin, not against the concentrate you started with.

The gap between these two numbers can be enormous. A fragrance oil used at 1% in a lotion, containing 2% Linalool, means the Linalool is actually present in the finished lotion at 0.02%, which is 200 ppm. That is not the 2% figure the supplier quoted you, and getting the two confused in either direction leads to real errors.

Doing the math correctly

The calculation is simple multiplication once you see it laid out:

Allergen % in finished product = (Allergen % in fragrance) × (Fragrance % in finished product)

Using the example above: 2% Linalool in the fragrance, multiplied by 1% fragrance in the lotion, equals 0.02% Linalool in the finished product. Converting that to parts per million: 0.02% equals 200 ppm.

Compare that to the Canadian leave-on threshold of 0.001% (10 ppm). At 200 ppm, this fragrance blend would trigger mandatory disclosure of Linalool by name in a leave-on product, even though "2 percent" sounds small and safe when you first read it on the supplier sheet.

Walking through a full example

Step	Value
Linalool percent in the fragrance oil (from supplier documentation)	2%
Fragrance oil percent used in the finished lotion	1%
Linalool percent in the finished lotion	0.02%
Linalool in ppm	200 ppm
Canada leave-on threshold	10 ppm
Result	Well above threshold, disclosure required

Now compare a rinse-off example with the same fragrance oil used at a lower rate:

Step	Value
Linalool percent in the fragrance oil	2%
Fragrance oil percent used in a rinse-off shampoo	0.3%
Linalool percent in the finished shampoo	0.006%
Linalool in ppm	60 ppm
Canada rinse-off threshold	100 ppm
Result	Below threshold, disclosure not triggered at this level

Same fragrance oil, same allergen, two different outcomes, purely because the finished-product percentage and the applicable threshold both shifted.

Why this trips people up so often

Fragrance and essential oil suppliers report their allergen breakdown as a property of the material they are selling, which makes sense from their side. But makers then plug that number directly into a compliance decision without the second multiplication step, treating "2% in the fragrance" as though it were "2% in the product." It is an easy mistake to make once and a genuinely costly one to repeat across a whole product line, especially with fragrance allergen disclosure becoming mandatory on Canada's Cosmetic Notification Form and label, List 1 in April 2026 and List 2 that August.

A habit that prevents the error

Whenever you get an allergen breakdown from a fragrance supplier, write your fragrance's use rate in the finished product right next to it before you do anything else. Do not let the supplier's percentage sit alone in your notes, because that is exactly when it gets mistaken for the finished-product figure weeks later when you are filling out a notification form.

This multiplication step, run across every allergen in every fragrance blend in a formula, is precisely the kind of repetitive, error-prone math Cosmetic Comply automates. It takes your ingredient list, applies the actual use percentages, and surfaces the finished-product concentration for each named allergen so the right numbers are the ones landing on your filing.