An allergen is a substance capable of causing an allergic reaction in certain sensitive individuals, particularly on the skin. In perfumery and cosmetics, this term refers to certain odorous molecules naturally present in fragranced materials, or used in compositions.

In the European Union, regulations require that certain fragrance allergens be listed on the label of cosmetic products if they exceed certain thresholds in the finished product:

• 0.001% for rinse-off products (perfumes, creams, lotions)

• 0.01% for rinse-off products (soaps, shower gels, shampoos)

Among the most well-known fragrance allergens are:

• Limonene

• Linalool

• Citral

• Geraniol

• Eugenol

These molecules are very often naturally present in essential oils and plant extracts.

The listing of these substances on the label does not mean that the product is dangerous: it simply serves to inform people who may be sensitive to them, in accordance with European regulations.

What causes a reaction in some people may be perfectly tolerated by the majority. Just like pollen, lactose, gluten or nuts.

Derived molecule

Masculine noun. Aromatic extract obtained by plant extraction with an organic solvent (usually hexane) first producing a concrete, then an absolute after alcoholic extraction. Origin: natural. Example: Jasmine absolute (Jasminum grandiflorum)

Olfactory construction resulting from the combination of several odorous materials producing a specific perception. Origin: natural, synthetic or mixed.

Noun, masculine. Molecules used for their powerful, luminous, brilliant, and slightly soapy olfactory effect. These molecules have played a major role in modern perfumery, particularly in the abstract floral compositions of the early 20th century. Chanel No. 5, created in 1921, is the most legendary perfume featuring them. Origin: synthetic.

Amber in perfumery does not correspond to the fossil resin amber in mineralogy. It is an olfactory accord with warm, balsamic, vanilla notes. Origin: natural or synthetic.

Masculine noun. Waxy substance produced in the intestine of the sperm whale (Physeter macrocephalus) and expelled into the sea. It results from a slow transformation of certain dietary components of the cetacean. After oxidation and aging at sea, ambergris develops a complex amber, animal, and marine odor. Historically highly valued as a fixative in perfumery, it is now almost entirely replaced by synthetic molecules. Origin: synthetic. The natural (animal) origin is extremely rare due to regulations in Europe.