Because something is natural doesn’t mean it’s good and allergens free!

It’s important to understand basic safety behind using even pure and natural products. If something is natural it doesn’t mean that using more is better and it’s going to work for everybody in the same way. There are some compounds found in natural essential oils which can cause irritations and allergies for people with sensitive skin.

“26 allergens” Legislation

EU Legislations are listing 26 allergens under the Directive 2003/15/EC. Interestingly 16 of them are occurring in natural complex substances (natural essential oils). Reasons for including these compounds as allergens has never been satisfactory explained therefore there is a lot of controversy around this list of potential allergens.

Prof. Schnuch’s Research

Thanks to extended studies undertaken in Germany by Prof. Schnuch in 2004 with network of dermatologists we gained much bigger insight into the topic of 26 allergens. In conclusion not all the 26 allergens identified in the 7th Amendment to the Cosmetics Act carry the same risk and therefore they should not be treated equaly. According to the new report 26 allergens are classified accordingly:

  • 4 Strong potent allergens
  • 3 Less potent allergens
  • 6 Rarely found as allergens
  • 13 Risk of being an allergen too small to consider

This scientific research completely changed the view how we should really treat those potential allergens and how they can influence our choice of products. Organisations like “Cropwatch” try for many years now to reverse “26 allergens” legislation.

If you wish to explore “26 allergens” in more details I grouped them and categorised them in the table below. Also more in depth information on individual allergens are presented below the table.

Enjoy exploring!

SUBSTANCE Ingredient type CAS NUMBER Natural Naturally occurring in complex biological substances/can be also synthetically produced Synthetics
CITRAL III 5392-40-5 *
EUGENOL III 97-53-0 *
ISO EUGENOL I 97-54-1 *
CINNAMAL I 104-55-2 *
COUMARIN IV 91-64-5 *
GERANIOL IV 106-24-1 *
FARNESOL III 4602-84-0 *
LINALOOL IV 78-70-6 *
LIMONENE IV 5989-27-5 *
  • Amyl Cinnamal (III) – It is synthetically produced scent ingredient used in production of perfumes and fragrances and can be found in fragrance oils like: tuberose, peach, cherry, honeysuckle etc. Risk of Amyl Cinnamal of being allergen is very rare.
  • Benzyl Alcohol (IV) – Very weak sensitizer found naturally in wide range of plants.
  • Cinnamyl Alcohol (II) – Can have sensitizing effect on some people and it’s known as potent allergen. It is an organic compound with hyacinth like odour and can be found in esterified form in Storax, Balsam Peru, Cinnamon leaves.
  • Citral (III) – It’s also called lemonal and is naturally present in essential oils of several plants like: lemon tea tree (70-80%), lemon grass (80%), petitgrain (36%), lime (6-9%), lemon (2-5%), orange (1%). It has citrus effect, strong antimicrobial qualities and pheromonal effect in insects. Two studies have shown 1-1.7% of people to be allergic to citral and allergy are frequently reported.
  • Eugenol (III) – Can be naturally found and extracted in some essential oils like: clove, nutmeg, cinnamon, basil, bay leaf etc. It is hepatotoxic, which means it can be toxic to the liver. It is rarely found in perfumery to be a sensitizer and allergen.
  • Hydroxy-citronellal (II) – This synthetic compound is not found in nature. It has floral like odour and can be prepared by hydration of citronellal. It is classified as potent allergen.
  • Isoeugenol (I) – It is naturally occurring strong potent allergen. It is derived from essential oils like: nutmeg, ylang-ylang, clove, cinnamon.
  • Amyl cinnamyl alcohol (IV) – It is synthetically produced compound which have a light floral odour. It gives very small risk of being allergen.
  • Benzyl salicylate (IV) – It is naturally occurring compound in a variety of plants like jasmine or ylang-ylang and most frequent used in cosmetics as UV light absorber. It has mild sweet floral odour. It is reported very rarely to cause irritations, sensitization and allergic reaction.
  • Cinnamal (I) – It is naturally occurring compound, classified as strong potent allergen. It is present in balsam of Tolu and Peru, hyacinth plant, cinnamon etc. It has strong, sweet, balsamic odour.
  • Coumarin (IV) – Found naturally in many plants, in high concentration in tonka bean and vanilla. It is also found in lavender, citrus fruits, strawberries, apricot, cherries and cinnamon. It has shown many biological activities: anti-HIV, anti-tumour, anti-inflammatory, anti-osteoporosis, antiseptic, analgesic. The research show than coumarin has very weak sensitizing properties, if any! In the humans pure coumarin is extremely well tolerated.
  • Geraniol (IV) – Occurs naturally in over 250 essential oils, it is a primary part of rose and citronella oil. It has rose like scent. Pure form of geraniol brings small risk of being allergen, where autoxidation (exposure to air) of geraniol form highly allergenic compound and greatly influence its sensitising capacity.
  • Hydroxy-methylpentylcyclohexenecarboxaldehyd (II) – It’s also known as Lyral. This synthetic compound is classified as potent allergen and important sensitizer in Europe.
  • Anise alcohol (IV) – It’s naturally occurring, very weak sensitizer. Risk of anise alcohol of being allergen is very small. It gives floral aroma.
  • Benzyl cinnamate (IV) – It occurs naturally in a various species of balsams such as Peru or Toru balsam. It is usually produced synthetically and has very weak sensitising potential. It has sweet, balsamic odour.
  • Farnesol (III) – Natural compound, found in many essential oils like: citronella, neroli, lemon grass, tuberose, rose and with sweet floral aroma. It has been suggested to have anti-tumour function (when inhaled as an aerosol it has shown capability to kill cancer cells in the lungs) and also possess anti-bacterial activity. Some people may become sensitive to it, however evidence that farnesol can cause allergic reaction in humans is disputed. It is cited as an infrequent but important cause of allergic contact dermatitis, but in general has very low potential for sensitization.
  • Butylphenyl methylpropional (lilial) (III) – It is synthetic compound with Lily of the Valley aroma. Can sometimes act as an allergen and may cause contact dermatitis, but in general very rare can cause allergies.
  • Linalool (IV) – It is a natural component found in many flowers and a various herbs: lavender, mint, coriander, basil. It is produced by over 200 species of plants: cinnamon, rosewood, citrus fruits, palmarosa, sweet orange. It has floral scent with a touch of spiciness. Can become allergenic when in contact with oxygen, but pure form of linalool give a very small risk of causing allergy.
  • Benzyl benzoate (IV) – It can be natural or synthetic. It is an ester of benzyl alcohol and benzoid acid. It is a natural compound of many essential oils like: cinnamon, jasmine, ylang-ylang, rosewood, benzoin. It has sweet, balsamic aroma. It has a variety of use: anti-parasitic insecticide, fixative in fragrances, food additive, preservative and solvent. The side effect of using it only has being seen at high doses and concentrations. Has being shown to irritate the skin of some individuals, but in general risk of benzyl benzoate to cause allergy is very low.
  • Citronellol (IV) – Natural compound found in citronella, rose and geranium oil. It is very important aromatic isolates used widely in food, soaps, cosmetics, pharmaceutical products and tobaccos. Study indicates that geraniol and citronellol have a low potential for skin penetration. Citronellol has being shown to be an antioxidant. It raises a low level of health concern, may cause contact allergy reaction in fragrance sensitive consumers.
  • Hexyl cinnamal (IV) – Synthetic, organic compound which resembles the naturally occurring spicy cinnamic aldehyde, but it possess a subtle, floral character. It has jasmine like odour. It can become an irritant in concentrations higher than recommended. It carries small risk of causing allergic reaction.
  • D-Limonene (IV) – Naturally occurring hydrocarbon classified as a cyclic terpene. Citrus fruits contains considerable amount of this compound, which contributes to their orange like odour. D-limonene is used in food manufacturing and some medicines, as a fragrant in perfumery and as botanical insecticide. In the natural medicine d-limonene is marked to relieve gastroesophageal refeux disease and heartburn. Limonene and its oxidation products can be skin and respiratory irritants and limonene-1,2-oxide is a known skin sensitizer. A study of patients presenting dermatitis showed that 3% were sensitised to limonene. It is consider by some researchers to be a chemo preventive agent with value as a dietary anti-cancer tool in humans.
  • Methyl 2-octynoate (III) – Also known as methyl heptin carbonate this synthetic compound has green, vegetable, violet like odour. A review of literature shows only one published clinical case where a possible causal link to a cosmetic product has been established. Tests have demonstrated a significant sensitisation potential but reports of clinical cases of allergy to methyl herpin carbonate are very rare with no new reports in the last two decades.
  • Alpha-isomethyl ionone (IV) – or alpha-cetone it is a synthetic compound used in fragrance industry characterised by violet sweet or powdery floral/woody violet odour. It has weak sensitising properties.
  • Oakmoss and Treemoss extract (I) – Naturally occurring strong potent allergens. Oakmoss is one of 8 ingredients of the Fragrance Mix used for diagnosing perfume allergy. Oakmoss products have been identified among the most frequent fragrance contact sensitizers.