Fragrance Allergens That Also Sit on the Hotlist

Here's a detail that trips people up: an ingredient being a declarable fragrance allergen and an ingredient being restricted on the Cosmetic Ingredient Hotlist are two completely separate rules, and a single substance can be caught by both at once. Eugenol is a good example. It is a well-known fragrance allergen that also appears with its own entry and considerations on the Hotlist side. Treat the allergen disclosure requirement and the Hotlist check as one task, and you will miss one of them.

Two different questions, one ingredient

The fragrance allergen rule asks: does this substance need to be named on the label and the CNF because it can trigger a reaction in sensitized individuals. The Hotlist rule asks something entirely different: is this substance's presence in a cosmetic restricted or prohibited outright, regardless of whether anyone is allergic to it.

An ingredient can be:

• Just a declarable allergen, with no separate Hotlist restriction.
• Just Hotlist-restricted, with no allergen disclosure requirement.
• Both at once, meaning it needs allergen disclosure above the trigger threshold and it needs to stay under whatever ceiling the Hotlist sets for that ingredient and product type.

Eugenol falls into that last group for many formulators, since it is one of the recognized fragrance allergens (commonly found in clove-derived essential oils and some other botanicals) and it also warrants a Hotlist check depending on concentration and product type. Coumarin is another substance worth double-checking on both fronts, given how often it appears naturally in tonka bean and some other botanical extracts used in fragrance work.

Why this catches naturals-focused brands especially hard

If your fragrance comes from essential oils rather than a synthetic fragrance compound, you are more exposed to this overlap, not less. Essential oils are natural mixtures, and a single oil can carry several allergens at once, some of which may also carry separate Hotlist considerations. Clove bud oil, for instance, is prized for its eugenol content precisely because eugenol is the active aromatic and antimicrobial component, which means a formulator reaching for clove oil for its scent or its preservative-boosting reputation is deliberately increasing the concentration of a substance that needs checking on two separate lists.

The disclosure thresholds, as a reminder

Allergen disclosure is triggered above 0.001% (10 ppm) in leave-on products and above 0.01% (100 ppm) in rinse-off products. List 1, the original fragrance allergen set, becomes mandatory on the CNF and the label on April 12, 2026. List 2, an expanded set aligned with international lists, becomes mandatory August 1, 2026. Common allergens across both lists include Limonene, Linalool, Citronellol, Geraniol, Eugenol, and Coumarin, all of which occur naturally in a wide range of essential oils.

A working checklist table

Ingredient	Allergen status	Hotlist consideration	Common natural source
Eugenol	List 1 declarable allergen	Check current Hotlist entry and limit for your product type	Clove bud oil, some cinnamon leaf oil
Coumarin	List 1 declarable allergen	Check current Hotlist entry	Tonka bean absolute, some lavender-adjacent botanicals
Linalool	Declarable allergen	Verify against current Hotlist before assuming no restriction	Lavender, bergamot, many florals
Citronellol	Declarable allergen	Verify against current Hotlist before assuming no restriction	Rose, geranium, citronella

Treat this table as a starting point for what to check, not a final answer. Hotlist entries and their limits change, and the safest habit is confirming the current status of every fragrance constituent against the live Hotlist at filing time, not from memory or an old printout.

What this means for your filing workflow

Do not treat allergen disclosure and Hotlist screening as two boxes you check with one glance at an ingredient name. Run each fragrance constituent through both checks separately: first, is it above the disclosure threshold for your product type (leave-on or rinse-off), and second, does its concentration sit under whatever the current Hotlist says for that ingredient. An essential oil blend with several allergens can pass the disclosure check easily (you just name what's above threshold) while still failing the Hotlist check if one constituent's concentration is too high, or vice versa.

This double-checking is genuinely tedious to do ingredient by ingredient across a full fragrance blend, especially once you are tracking two allergen list deadlines alongside Hotlist limits. It's part of why Cosmetic Comply screens every mapped ingredient against both the current Hotlist and the applicable allergen thresholds in one pass, flagging overlaps like this with a confidence score before a human reviewer signs off and the notification gets filed.