HYDROXYCITRONELLAL

Name / description

Hydroxycitronellal; 7-Hydroxy-3,7-dimethyl-1-octanal

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Function(s) of this ingredient in cosmetic products

FRAGRANCE

Enhances the smell of a product and / or perfumes the skin

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Origin

synthetic

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Occurrence in cosmetics

Perfumes, toilet waters, aftershaves, various perfumed cosmetics

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Occurrence in other products

Perfumed cleaning agents, as flavouring agent in foodstuffs

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Background information on use in cosmetics

Hydroxycitronellal occurs in several essential oils but is also synthetically produced by hydration of citronellal. Hydroxycitronellal has a sweet, flowery fragrance which is reminiscent of lilac, lily, linen or lily of the valley. Because of its adhesive strengths hydroxycitronellal has excellent fixing properties as a perfume ingredient and is, more particularly, contained in perfumes with flower character. Declarable fragrance in accordance with Article 19 Para 1g of the EC Cosmetics Regulation. Fragrances or mixtures of fragrances are often referred to in the cosmetics area as "perfuming agents" or "perfume oils" or "parfum oils". On the cosmetic products they are declared with the INCI name "PARFUM". These are undiluted individual substances or their mixtures which originate from natural raw materials or can be produced (semi-) synthetically. They are starting materials for the production of perfume, eau de parfum, eau de toilette, eau de cologne and other perfumed cosmetic products. The average content of fragrances amounts in perfume to 15-30 %, in eau de parfum to 10-14 %, in eau de toilette to 6-9 %, in eau de cologne to 3-5 % as well as in skin creams, shampoos, hair and deodorant sprays to approximately 0.2-1 % and approximately 1-3 in deodorant sticks. The perfume oils include essential oils, resinoids and absolutes. The sources are, amongst others, flowers, leaves and stems, fruits and fruit peels or roots of plants; woods, grasses or herbs, needles, resins and balsams. Moreover, only compounds isolated from natural products such as aldehydes, ketones, esters, alcohols etc. are used (geraniol, citronellal, citral, eugenol, menthol) as well as semi-synthetic (citronellol, geranyl acetate, jonone) and synthetic scents (eg phenylethyl alcohol and linalool) are used. Scents of animal origin such as musk and ambra are only rarely used.

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Information on safe use

Because of their allergological relevance 26 individual fragrances must be declared in the EU on the packaging of cosmetic products separately. These are alpha-isomethyl ionone, amyl cinnamal, amylcinnamyl alcohol, anise alcohol, benzyl alcohol, benzyl benzoate, benzyl cinnamate, benzyl salicylate, butylphenyl methylpropional, cinnamal, cinnamyl alcohol, citral, citronellol, coumarin, eugenol, Evernia furfuracea extract, Evernia prunastri extract, farnesol, geraniol, hexyl cinnamal, hydroxycitronellal, hydroxyisohexyl 3-cyclohexene carboxaldehyde, isoeugenol, limonene, linalool und methyl 2-octynoate. The labelling of these substances helps allergy sufferers who know that they react allergically to one or more of these substances, to avoid the products. According to a large European study approximately 2 % of the population suffer from a contact allergy against at least one fragrance, whereby women are affected twice as often as men. If there is an initial suspicion of a fragrance allergy, the allergist can carry out an epicutaneous test with two standardised fragrance series (the so-called fragrance mixes 1 and 2). In this connection the suspected allergens are fixed for two days in small cavities with a plaster on the skin on the back. It is observed whether a reaction with reddening and inflammation of the skin, ie an eczema develops in the test field. The two test series of allergenic fragrances allow the identification of a general sensitisation to fragrances in 70 to 80 % of the cases. Because of the partly very low concentration of individual fragrances in cosmetics the threshold concentration to trigger a contact allergy reaction of a substance vis a vis which there is a sensitisation is in many cases not reached under the application conditions, in particular for products which are rinsed off again after use (so-called rinse-off products). In the event of a positive test reaction to a fragrance mix it is by all means required to retest the individual components of the mix. Only then is it possible to precisely state the substances to which the person is allergic. This substance is expressly approved and / or subject to a restriction as a result of an entry in Annex III of the EC Cosmetics Regulation after an assessment by the Scientific Committee on Consumer Safety of the EU Commission (SCCS). Restrictions can relate eg to purity criteria, a maximum concentration or the restriction to certain product categories. Subject to the conditions possibly imposed in Annex III, the use of this substance in cosmetic products is safe.

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Further information

For the clarification of a suspicion of a contact allergy this substance can be routinely tested in the epicutaneous test at the dermatologist.

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Belongs to the following substance groups

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Regulating cosmetics

Cosmetics Ingredients are subject to regulation. Please note, different regulations may apply to cosmetic ingredients outside the EU.