Fragrance Allergens: What the Science Actually Says

The Numbers Are Clear

According to a landmark 2015 study across five European countries, 1-3% of the general population has clinically relevant fragrance allergy. Among dermatitis patients, that number jumps to approximately 16%.

These aren't small numbers. In a population of 450 million Europeans, we're talking about 4.5 to 13.5 million people who react to fragrance ingredients in their skincare.

Key Statistics at a Glance

Population	Sensitization Rate	Source
General population (EU)	1-3%	Diepgen 2015
Dermatitis patients (EU)	~16%	SCCS 2012
Fragrance Mix I	6.81%	Botvid 2024
Oxidized Linalool	11.7%	Dittmar 2019
Oxidized Limonene	9.4%	Dittmar 2019

The 82 Regulated Allergens

In 2023, the EU expanded its fragrance allergen labeling requirements from 26 substances to 82 substances. This wasn't arbitrary - it was based on decades of clinical patch test data and the comprehensive SCCS Opinion (SCCS/1459/11).

The SCCS identified 82 substances as "established human contact allergens" - 54 individual chemicals and 28 natural extracts. Among these, 12 chemicals are classified as "high-risk" with over 100 reported cases each:

Cinnamal - Cinnamon fragrance
Cinnamyl alcohol - Cinnamon-related
Citral - Lemon scent (in lemongrass, verbena)
Coumarin - Vanilla-like
Eugenol - Clove scent
Farnesol - Floral
Geraniol - Rose-like
Hydroxycitronellal - Lily of the valley
HICC/Lyral - Now BANNED (>1,500 cases)
Isoeugenol - Clove-related
Oxidized limonene - Citrus
Oxidized linalool - Lavender/floral

The Oxidation Problem

Here's something most people don't know: limonene and linalool themselves are weak sensitizers. The problem is their oxidation products - the hydroperoxides that form when these terpenes are exposed to air and light.

A 2019 Dutch study found that oxidized linalool has an 11.7% sensitization rate among dermatitis patients. Oxidized limonene hits 9.4%. These are now among the most common fragrance allergens - more prevalent than traditional fragrance markers.

What This Means For You

Products with limonene/linalool should contain antioxidants (BHT, tocopherol)
Check expiration dates - oxidation increases over time
Store products away from heat and light
The SCCS recommends maximum 10 ppm total hydroperoxides
Current EU labeling requirements don't distinguish oxidized forms - this is a regulatory gap

Essential Oils: Not Always "Natural" and "Safe"

According to the German IVDK database (2010-2019), 8.3% of dermatitis patients react to at least one essential oil. The highest sensitization rates:

Ylang Ylang Oil - 3.9% (highest)
Lemongrass Oil - 2.6%
Jasmine Absolute - 1.8%
Sandalwood Oil - 1.8%
Clove Oil - 1.6%
Neroli Oil - 1.1%

Massage therapists and cosmeticians show significantly elevated risk due to repeated exposure. If you work in these fields, this is especially relevant.

The Banned Substances

Three fragrance ingredients have been completely banned in the EU:

PROHIBITED in EU Cosmetics

HICC (Lyral) - Banned 2021
Over 1,500 sensitization cases. No safe use level could be established.
Atranol - Banned 2017
Oak moss constituent. Extreme sensitization potential.
Chloroatranol - Banned 2017
Tree moss constituent. No safe use level.

How to Read Labels

Under EU regulation, fragrance allergens must be declared when they exceed:

10 ppm (0.001%) in leave-on products
100 ppm (0.01%) in rinse-off products

If you see individual fragrance components listed (linalool, limonene, citronellol, etc.) in the ingredient list, they're present above these thresholds. If you only see "Parfum" or "Fragrance," the individual allergens may still be present - just below labeling thresholds.

The Bottom Line

Fragrance allergens are the leading cause of cosmetic-related contact dermatitis worldwide. The science is clear:

1-3% of the general population is affected
Oxidized terpenes (limonene/linalool hydroperoxides) are now top allergens
Essential oils carry real sensitization risk - "natural" doesn't mean "safe"
The EU's 82-allergen labeling system is evidence-based
Product storage and freshness matter

If you have sensitive skin or known fragrance allergies, use our Product Decoder to check ingredient lists before purchasing.

References

Botvid S, et al. (2024). Contact sensitization to fragrance mix I and fragrance mix II among European dermatitis patients: A systematic review. Contact Dermatitis. DOI: 10.1111/cod.14618
Diepgen TL, et al. (2015). Prevalence of fragrance contact allergy in the general population of five European countries: a cross-sectional study. British Journal of Dermatology. DOI: 10.1111/bjd.14151
Dittmar D, Schuttelaar MLA. (2019). Contact sensitization to hydroperoxides of limonene and linalool. Contact Dermatitis. DOI: 10.1111/cod.13137
Geier J, et al. (2022). Contact sensitization to essential oils: IVDK data of the years 2010-2019. Contact Dermatitis. DOI: 10.1111/cod.14126
SCCS. (2012). Opinion on Fragrance allergens in cosmetic products. SCCS/1459/11. European Commission.
EU Regulation 2023/1545 amending Annex III to Regulation (EC) No 1223/2009.