A Worked Example: Passing One Restricted Entry Correctly

Say you're formulating a leave-on facial serum with a boron-based buffering ingredient in the mix, and your ingredient screen flags it as restricted rather than prohibited. That flag alone tells you nothing useful yet. What you need is the actual entry, the actual math, and a decision about whether your formula fits inside the line the Hotlist draws. Let's walk through it the way you'd actually do it on a real notification.

Start with the entry itself, not the flag

The Cosmetic Ingredient Hotlist splits substances into two buckets: those that can't appear in a cosmetic at all, and those that can appear but only under conditions, usually a maximum concentration, sometimes a restriction to certain product types or a required warning statement. A "restricted" flag means you're in the second bucket. Before you touch your formula, pull the actual Hotlist entry and read every column. The concentration limit is often expressed against the finished product as sold, not against a raw material or a supplier blend, and that distinction is where most mistakes happen.

For our example, imagine the entry caps the ingredient at 3% in the finished product, with no restriction on product category. Simple enough on paper.

Do the concentration math against the finished product

Here's where it gets real. Suppose you're using a supplier-blended additive that's 60% of the restricted substance and 40% carrier. You're using that blend at 8% of your total formula. The actual concentration of the restricted substance in your finished serum is:

0.60 x 8% = 4.8%

That's above the 3% ceiling, even though "8%" sounds modest on your batch sheet. This is the single most common way a restricted entry gets missed: makers screen the blend's trade name or check the raw material percentage, not the true finished-product concentration of the actual restricted substance inside it.

To pass, you'd need to either cut the blend's use level (to keep the substance under 3%, you'd want roughly 5% blend or less) or reformulate with a lower-concentration version of the additive.

Rebuild the formula and recheck

Once you drop the blend to 4.5% of the formula, the math becomes:

0.60 x 4.5% = 2.7%

That's under the 3% limit. Rerun the full formula through your screening step again, not just this one line, because changing one ingredient's percentage shifts everyone else's share of the total too if you're working in percent-of-batch rather than absolute grams.

What goes on the Cosmetic Notification Form

Once the formula is clean, the CNF needs:

Field	What you enter
Ingredient name	INCI name of the restricted substance, plus the carrier if it's separately notifiable
Concentration	The true post-dilution percentage (2.7% in our example), or an approved concentration range
Function	Its actual role in the formula (buffering agent, in this case)
Product category	Leave-on facial

Health Canada wants the INCI name and a concentration or range, not the supplier's trade name for the blend. If your formula changes again later, even by a percent, that's an amendment to the existing Cosmetic Notification, not a brand-new filing.

The 10-day clock still applies

None of this changes your timing obligation. The CNF is due within 10 days of first sale, and it's a notification, not a pre-market approval, so you're not waiting on a green light from Health Canada before you can ship. But that also means the burden of getting the concentration math right sits entirely with you. There's no reviewer catching a bad calculation before it happens; the exposure is remediation after the fact if it's ever checked.

A few things to check before you file

• Confirm the Hotlist limit applies to the finished product and not a raw material, since both formats exist across different entries.
• Trace every supplier blend back to its component percentages before you calculate anything.
• Recheck the whole formula after any single ingredient adjustment, not just the line you changed.
• Keep your math on file. If Health Canada ever asks how you arrived at a concentration, "the supplier blend was 8%" isn't an answer, but "0.60 x 4.5% = 2.7%" is.

This kind of worked calculation is exactly the part Cosmetic Comply automates for you: it expands supplier blends into their real components, carries the percentages through to the finished product, and screens the result against the Hotlist with a confidence score before a human reviewer signs off and the filing goes in. If you're doing this math by hand on every reformulation, it's worth seeing what a second set of eyes, human and otherwise, catches.