Monoterpene with citrus scent, a natural component of lemon and orange essential oils. Listed among the 26 mandatory EU fragrance allergens.
Topical application
CWeak evidence. In vitro data, open-label studies, or expert consensus.
Oxidized limonene ranks among the top fragrance allergens by positive patch-test frequency. Listed separately on labels at 0.001%+ in leave-on cosmetics.
Limonene is a monoterpene with a characteristic citrus scent. Main component of citrus peel essential oils: orange (90–95%), lemon (60–70%), mandarin, grapefruit. In cosmetics it appears either as part of essential oil or as isolated fragrance. Mechanism. Limonene itself has no cosmetic action – it is a scent component. The molecule rapidly oxidizes in air to form hydroperoxides (limonene-1-hydroperoxide and others), which are the actual contact allergens. Oxidized limonene is significantly more dangerous than fresh. Where applied. Almost any fragranced cosmetics: creams, shampoos, soaps, deodorants, perfumery. The EU lists limonene among the 26 mandatory fragrance allergens: above 0.001% in leave-on and 0.01% in rinse-off, manufacturers must declare it on the label. Allergenicity evidence base. Contact allergy to oxidized limonene is confirmed in multicenter patch-test studies by the European EECDRG group: sensitization prevalence 0.9–3.2% in the general population, up to 5–7% in eczema patients (Christensson 2014, Bråred Christensson 2016). Patch tests with fresh limonene rarely turn positive – the reaction targets the oxidation products. 'Natural vs synthetic' controversy. Natural cosmetics marketing positions limonene as 'natural', opposed to 'chemical' fragrances. From an allergy standpoint there is no difference: the molecule is the same and oxidizes the same way. Natural products with citrus essential oils often contain more limonene than mass-market cosmetics with synthetic fragrance. Who should avoid it. Atopic dermatitis, rosacea, perioral dermatitis, history of contact dermatitis – any fragranced cosmetics with limonene are unsuitable. For sensitive skin, choose 'fragrance-free' ranges (La Roche-Posay Toleriane, Avène Tolerance Control, CeraVe). In pregnancy and lactation – use topically with caution due to frequent sensitization; oral use (essential-oil supplements) is better avoided because terpene effects on the fetus are not studied.
Irritation potential
MediumAllergen risk
HighPregnancy
CautionThe Evigrade extension adds an evidence panel to Wildberries, Goldapple, Letu, iHerb, Sephora and 12 more stores. This ingredient and every other one in the product show evidence-tier, allergen risk and pregnancy/lactation flags at a glance.
Limonene should be used with caution during pregnancy. Consulting a dermatologist or OB-GYN is advisable.
Limonene suits: normal. Use with caution in: sensitive, dry.
Limonene has moderate irritation potential. Sensitive skin may show a transient reaction that usually settles with adaptation.
Limonene has high allergen potential. Perform a patch test on the inner forearm 24 hours before facial application.
Monoterpene with citrus scent, a natural component of lemon and orange essential oils.
Published: · updated:
For sensitive skin
Oxidizes on air to highly allergenic hydroperoxides. Sensitive and atopic skin should avoid it.
Suitable for
Use with caution
The INCI name is Limonene.