CYCLOPENTASILOXANE

Name / description

Cyclopentasiloxane; Decamethylcyclopentasiloxan, D5

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Function(s) of this ingredient in cosmetic products

HAIR CONDITIONING

Leaves the hair easy to comb, supple, soft and shiny and / or imparts volume

SKIN CONDITIONING

Maintains the skin in good condition

SKIN CONDITIONING - EMOLLIENT

Softens and smoothens the skin

SOLVENT

Dissolves other substances

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Origin

synthetic

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Occurrence in cosmetics

Haircare products, styling products and other cosmetic products

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Background information on use in cosmetics

Synthetic polymer organosilicone compounds. Silicones are insoluble in water but well emulsifiable. Decamethylcyclopentasiloxane renders the hair easily combable, smooth, soft and shiny. Silicones, chemically more precisely poly(organo)siloxanes, is a designation for a group of synthetic polymers in which silicone atoms are connected through oxygen atoms. The volatility and viscosity are determined by the chain length. The silicones include various compounds which contain as a characteristic functional group a polyorganosiloxane. Important classes are: dimethylpolysiloxanes, phenylmethyl polysiloxanes, cyclic methylsiloxanes and siloxanes modified with alkyl groups or PEG (polyethylene glycol). Silicones are water insoluble and have a low surface tension. The low surface tension is the reason for their good spreading quality; they constitute protective films on the skin which are vapor-permeable. They have no comedogenic effect and are particularly well tolerated on skin. Because of their favourable technological and cosmetic properties they are used rather frequently in cosmetics and serve for the improvement of care properties in skin and haircare products.

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Information on safe use

Decamethylcyclopentasiloxane may only be used because of environmental aspects after 31 January 2020 up to 0.1 % in cosmetic products which can be rinsed off with water after their application.

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Why are we talking about it?

Cyclopentasiloxane (D5) is suspected of being an endocrine disruptor and a pollutant through accumulation and persistence in the environment. The facts: If in vitro studies (referring to studies carried out in an artificial laboratory environment, for instance in a test tube) seem to show a weak activity on the oestrogens of D4 (substance prohibited in cosmetic products); these data are not confirmed in vivo (referring to studies carried out on living organisms) and the in vitro studies do not show an endocrine disrupting potential for D5. Furthermore, dermal absorption of D5 is minimal. This is why European experts consider its use in cosmetic products to be safe (1). D5 is classified as very persistent and accumulating in the environment, which has led to its limitation to a very low dose in rinse-off cosmetic products (as they are then washed out in the rinsing water). A limitation to this very low dose is also being considered in leave-on cosmetic products. Key points to take away: D5 is not considered an endocrine disruptor. Its use in cosmetic products is safe. Measures have been taken by European experts to limit the release of D5 into waters because it is very persistent and very bioaccumulative. Sources: (1) Opinion of the European Scientific Committee on Consumer Safety SCCS/1549/15: https://ec.europa.eu/health/scientific_committees/consumer_safety/docs/sccs_o_174.pdf

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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.