TETRAMETHYL ACETYLOCTAHYDRONAPHTHALENES

Name / description

Octahydrotetramethyl-2-naphthylethan-1-one (mixture of isomers)

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Function(s) of this ingredient in cosmetic products

FRAGRANCE

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

SKIN CONDITIONING - MISCELLANEOUS

Maintains the skin in good condition

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Origin

synthetic (Information may exclusively reflect the status at initial entry of this ingredient into the relevant INCI dictionary; technological progress may have added new manufacturing options based on substances of different origin)

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Background information on use in cosmetics

According to the EU Cosmetic Products Regulation, this ingredient must be individually listed on a cosmetic product label. For more information on fragrance allergens labelling requirements, see Information on Safe Use section. 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, compounds isolated from natural products such as aldehydes, ketones, esters, alcohols etc. are used (geraniol, citronellal, citral, eugenol, menthol). Semi-synthetic (citronellol, geranyl acetate, jonone) and synthetic scents (eg phenylethyl alcohol and linalool) are used too. Scents of animal origin such as musk and ambra are only rarely used.

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Information on safe use

Some cosmetic ingredients can act as allergens for certain people. This does not mean that the ingredient is unsafe for everyone; it simply means that people who know they are allergic to a specific substance should avoid products that contain it. To support these consumers in the EU, manufacturers highlight the presence of potential fragrance allergens individually on product labels. This allows people with known fragrance allergies to quickly spot and avoid ingredients that may trigger a reaction. The list of fragrance allergens that need to be labelled by name on a cosmetic product is defined in Annex III of the EU Cosmetic Products Regulation (CPR). Such labelling is required when a substance is present in a product above 0.01 % for rinse-off products and 0.001% for leave-on products. In line with the latest amendments to the CPR, from 31 July 2026 cosmetics manufacturers will label 81, instead of 24, fragrance allergens used in products newly placed on the EU market. Products already on the market and not yet meeting the latest labelling requirements must be sold off by 31 July 2028. The change in labelling requirements does not reflect any change in products safety or in their formulations, which already must comply with strict EU safety requirements. The purpose of updated labelling is to provide sensitized consumers with information on the presence of additional fragrance allergens, empowering them to make informed choices and easily identify substances they might be allergic to. Testing for fragrance allergies If a fragrance allergy is suspected, doctors usually start with a simple skin test called a patch test. Small amounts of common contact allergens — including two standard fragrance mixtures (so-called fragrance mix 1 and 2) — are placed on patches and applied to the skin on the patient’s back. The patches stay on for about two days. After the patches are removed, the doctor checks the skin to see if any allergic eczema like reactions appear. This helps show whether the skin reacted to any of the tested substances. The two fragrance mixtures used in this test include 14 ingredients that are currently required to be labelled on cosmetic products. If someone reacts to one of the mixtures, the doctor will then test the individual ingredients separately to find out which specific substance triggers the allergy. 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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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.