Overview
What it is
Hair serum with 19 ingredients
Cool Features
It is cruelty-free, fungal acne (malassezia) safe, and reef safe
Suited For
It has ingredients that are good for dry skin, sensitive skin and scar healing
Free From
It doesn't contain any oils, parabens or sulfates
Fun facts
BioSilk is from United States. This product is used in 24 routines created by our community.
We independently verify ingredients and our claims are backed by peer-reviewed research. Does this product need an update? Let us know.
What's inside
Ingredients List
Cyclopentasiloxane
EmollientCyclotetrasiloxane
EmollientDimethiconol
EmollientCyclohexasiloxane
EmollientAlcohol Denat.
AntimicrobialC12-15 Alkyl Benzoate
AntimicrobialPhenoxyethanol
PreservativePanthenol
Skin ConditioningEthyl Ester Of Hydrolyzed Silk
Skin ConditioningParfum
MaskingBenzyl Benzoate
AntimicrobialHexyl Cinnamal
PerfumingLinalool
PerfumingAlpha-Isomethyl Ionone
PerfumingCitronellol
PerfumingGeraniol
PerfumingHydroxycitronellol
PerfumingButylphenyl Methylpropional
PerfumingEugenol
PerfumingCyclopentasiloxane, Cyclotetrasiloxane, Dimethiconol, Cyclohexasiloxane, Alcohol Denat., C12-15 Alkyl Benzoate, Phenoxyethanol, Panthenol, Ethyl Ester Of Hydrolyzed Silk, Parfum, Benzyl Benzoate, Hexyl Cinnamal, Linalool, Alpha-Isomethyl Ionone, Citronellol, Geraniol, Hydroxycitronellol, Butylphenyl Methylpropional, Eugenol
Benefits
Concerns
Ingredients Explained
Cyclopentasiloxane (D5) is a lightweight silicone that mostly acts as an emollient and solvent in cosmetics. Its the reason your products feel silky, fast-spreading, and non-greasy.
Since D5 is volatile, it does its thing and then evaporates off the skin quickly.
The safety profile of this ingredient is reassuring; the US CIR Expert Panel concluded D5 is safe as used in cosmetics and Health Canada concluded that D5 is not harmful to human health or the environment as currently used in cosmetics
There's a study that people mention about D5 in a rat study showing tumors. This study is related to long-term inhalation of high D5 levels.
Regulatory bodies have judged this study to be not applicable in topical skincare since skin absorption of D5 is very low and we're not really inhaling huge amounts of D5.
The only restriction for this ingredient is environmental. The European Chemicals Agency (ECHA) restricted D5 in wash-off cosmetics at or above 0.1% due to their persistence in water.
Learn more about CyclopentasiloxaneThis ingredient is a small silicone made to be silky and weightless. It works as an emollient and solvent for heavier pigments/silicones as well.
According to the CIR Expert Panel, this ingredient is considered gentle and doesn't penetrate deeply into skin.
The EU and UK have banned this ingredient in cosmetics since 2020. A separate EU REACH (Registration, Evaluation, Authorisation, and Restriction of Chemicals) rule caps D4 as a trace impurity at under 0.1% in any cosmetic.
In September of 2025, the US EPA's draft TSCA risk evaluation that came out in September 2025 preliminarily found D4 poses "unreasonable risk to human health and the environment". This could lead to restrictions in the next year or so.
Learn more about CyclotetrasiloxaneDimethiconol is a silicone that resembles the popular dimethicone. Like other silicones, it is an emollient. Emollients create a thin film on skin to prevent moisture from escaping.
This ingredient helps to create a silky texture and improve spreadability. Due to its high molecular weight and thickness, it is often combined with cyclopentasiloxane.
Cyclohexasiloxane is a type of silicone more commonly known as D6. It is an emollient and solvent.
Cyclohexasiloxane is used to evenly distribute ingredients throughout the product. When applied to the skin, Cyclohexasiloxane evaporates and leaves behind a silky feel.
As an emollient, it can help the skin feel soft and hydrated. It is also used to reduce frizz in hair products.
Learn more about CyclohexasiloxaneAlcohol Denat. is an alcohol with a denaturant property. It is created by mixing ethanol with other additives.
The "denat" part just means "denatured"; common denaturants include Denatonium Benzoate, t-butyl alcohol, and Diethyl Phthalate. This step makes the alcohol undrinkable (and lets brand skip taxes related to beverage alcohol).
This ingredient gets a bad rep because it is irritating and drying due to its astringent property. Astringents draw out natural oils in tissue to constrict pores and dry out your skin.
However, alcohol denat. is not all that bad.
Due to its low molecular weight, alcohol denat. tends to evaporate quickly. One study on pig skin found half of applied alcohol evaporated in 10 seconds and less than 3% stayed on skin.
This also helps other ingredients become better absorbed upon application.
Studies are conflicted about whether this ingredient causes skin dehydration. One study from 2005 found adding emollients to propanol-based sanitizer decreased skin dryness and irritation. Another study found irritation only occurs if your skin is already damaged.
Small amounts of alcohol are generally tolerated by oily skin or people who live in humid environments.
The rule of thumb is this ingredient will probably not affect your skin much if it is near the end of an ingredients list.
One thing to note:
People with ALDH2 (aldehyde dehydrogenase 2) deficiency may experience skin irritation from continued alcohol use. About 8% of the world's population have this deficiency.
The Cosmetic Ingredient Review Expert Panel has determined denatured alcohols to be safe for use in concentrations between 0.05% and 12% (depending on which denaturant is used).
Also...
This ingredient has antimicrobial and solvent properties.
The antimicrobial property helps preserve products and increase their shelf life. As a solvent, it helps dissolve other ingredients.
Look for formulas that contain glycerin, hyaluronic acid, or panthenol if you want to offset any drying effect.
This ingredient will trip away your skin's natural oils/lipids that help it lock in moisture. This can worsen dryness, trigger eczema flare-ups, and aggravate rosacea.
Be sure to patch test any product with this ingredient if you have dry or sensitive skin, eczema, or rosacea.
Learn more about Alcohol Denat.C12-15 Alkyl Benzoate is a lightweight emollient made by combinig benzoic acid with fatty alcohols that are 12-15 carbons long.
In cosmetics, it plays several roles:
The Cosmetic Review Expert Panel has concluded the alkyl benzoate group to be safe as used in cosmetics; it wasn't found to be a skin irritant and unlikely to be absorbed due to its low water solubility.
This report recorded almost 1000 reported uses with concentrations up to 59% in leave-on products but your cosmetics will typically use 0.5-15% depending on the product.
It's often called a "SPF booster": this is because it keeps UV filters properly dissolved and evenly distributed to support a sunscreen's performance. It doesn't actually raise SPF on its own.
Overall, this ingredient is well tolerated.
This ingredient is fungal acne safe.
The Malassezia yeast feeds on free fatty acids and this ingredient is made up of an aromatic acid and fatty alcohols.
When this ingredient breaks down, it yields benzoic acid (which is antifungal) and fatty alcohols. Neither of these have been found in studies to be a known food source for Malassezia.
Learn more about C12-15 Alkyl BenzoatePhenoxyethanol is a preservative that has germicide, antimicrobial, and aromatic properties. Studies show that phenoxyethanol can prevent microbial growth. By itself, it has a scent that is similar to that of a rose.
It's often used in formulations along with Caprylyl Glycol to preserve the shelf life of products.
Panthenol is a common ingredient that helps hydrate and soothe the skin. It is found naturally in our skin and hair.
There are two forms of panthenol: D and L.
D-panthenol is also known as dexpanthenol. Most cosmetics use dexpanthenol or a mixture of D and L-panthenol.
Panthenol is famous due to its ability to go deeper into the skin's layers. Using this ingredient has numerous pros (and no cons):
Like hyaluronic acid, panthenol is a humectant. Humectants are able to bind and hold large amounts of water to keep skin hydrated.
This ingredient works well for wound healing. It works by increasing tissue in the wound and helps close open wounds.
Once oxidized, panthenol converts to pantothenic acid. Panthothenic acid is found in all living cells.
This ingredient is also referred to as pro-vitamin B5.
Learn more about PanthenolWe don't have a description for Ethyl Ester Of Hydrolyzed Silk yet.
Parfum is a catch-all term for an ingredient or more that is used to give a scent to products.
Also called "fragrance", this ingredient can be a blend of hundreds of chemicals or plant oils. This means every product with "fragrance" or "parfum" in the ingredients list is a different mixture.
For instance, Habanolide is a proprietary trade name for a specific aroma chemical. When used as a fragrance ingredient in cosmetics, most aroma chemicals fall under the broad labeling category of “FRAGRANCE” or “PARFUM” according to EU and US regulations.
The term 'parfum' or 'fragrance' is not regulated in many countries. In many cases, it is up to the brand to define this term.
For instance, many brands choose to label themselves as "fragrance-free" because they are not using synthetic fragrances. However, their products may still contain ingredients such as essential oils that are considered a fragrance by INCI standards.
One example is Calendula flower extract. Calendula is an essential oil that still imparts a scent or 'fragrance'.
Depending on the blend, the ingredients in the mixture can cause allergies and sensitivities on the skin. Some ingredients that are known EU allergens include linalool and citronellol.
Parfum can also be used to mask or cover an unpleasant scent.
The bottom line is: not all fragrances/parfum/ingredients are created equally. If you are worried about fragrances, we recommend taking a closer look at an ingredient. And of course, we always recommend speaking with a professional.
Learn more about ParfumBenzyl Benzoate is usually created from the condensation of benzoic acid and benzyl alcohol. It is used as a preservative, solvent, and has a floral/balsamic scent in large amounts.
As a preservative, Benzyl Benzoate works against bacteria and fungus. It is often used to treat scabies and lice in medicine.
Solvents are used to keep ingredients together in a product. They can help dissolve ingredients to stable bases or help evenly distribute ingredients throughout the product.
Due to its fragrance, Benzyl Benzoate can be sensitizing and may cause contact dermatitis. It is a known EU allergen. We recommend speaking with a professional if you have any concerns.
Benzyl Benzoate can be naturally found in cranberries and peaches.
Learn more about Benzyl BenzoateHexyl Cinnamal is a fragrance ingredient with a similar scent to jasmine. It can be naturally found in chamomile essential oil.
This ingredient is a known EU allergen and may sensitize the skin. The EU requires this ingredient to be listed separately on an ingredients list.
Hexyl Cinnamal is not water soluble but is soluble in oils.
Learn more about Hexyl CinnamalLinalool is a fragrance and helps add scent to products. It's derived from common plants such as cinnamon, mint, citrus, and lavender.
Like Limonene, this ingredient oxidizes when exposed to air. Oxidized linalool can cause allergies and skin sensitivity.
This ingredient has a scent that is floral, spicy tropical, and citrus-like.
Learn more about LinaloolAlpha-Isomethyl Ionone is a fragrance. It can be synthetically created or naturally occurring.
The scent of Alpha-Isomethyl Ionone is described as "flowery" but can also be "woody".
Naturally occurring Alpha-Isomethyl Ionone may be found in Saccharomyces cerevisiae, or the yeast used to make wine and bread.
The term 'fragrance' is not regulated in many countries. In many cases, it is up to the brand to define this term. For instance, many brands choose to label themselves as "fragrance-free" because they are not using synthetic fragrances. However, their products may still contain ingredients such as essential oils that are considered a fragrance.
Learn more about Alpha-Isomethyl IononeCitronellol is used to add fragrance/parfum to a product. It is often derived from plants such as roses. In fact, it can be found in many essential oils including geranium, lavender, neroli, and more. The scent of Citronellol is often described as "fresh, grassy, and citrus-like".
Since the Citronellol molecule is already unstable, Citronellol becomes irritating on the skin when exposed to air.
Citronellol is a modified terpene. Terpenes are unsaturated hydrocarbons found in plants. They make up the primary part of essential oils.
Citronellol is not able to be absorbed into deeper layers of the skin. It has low permeability,
Citronellol is also a natural insect repellent.
Learn more about CitronellolGeraniol is used to add fragrance/parfum to a product. It is the main component of citronellol. It is a monoterpenoid and an alcohol.
Monoterpenes are naturally found in many parts of different plants.
Geraniol can be found in many essential oils including Rose Oil and Citronella Oil. The scent of Geraniol is often described as "rose-like". Many foods also contain Geraniol for fruit flavoring.
Geraniol can irritate the skin when exposed to air. However, irritation depends on the ability of geraniol to penetrate into the skin. In general, geraniol is not able to penetrate skin easily.
Geraniol is colorless and has low water-solubility. However, it is soluble in common organic solvents.
Like citronellol, it is a natural insect repellent.
2,6-Octadien-1-ol, 3,7-dimethyl-, (2E)-
Learn more about GeraniolHydroxycitronellol is a fragrance.
Butylphenyl Methylpropional is a synthetic fragrance. You might know it as "lilial". The scent of this ingredient is floral-like and similar to the scent of lily flowers.
In March of 2022, the EU banned this ingredient in both rinse-off and leave-on products. This is because research found Butylphenyl Methylpropional to disrupt fertility in rats.
This ingredient is also a known EU allergen, meaning it is likely to cause an allergic reaction. Irritated skin can be damaging.
We always recommend speaking with a professional if you have any concerns or questions about this ingredient.
Learn more about Butylphenyl MethylpropionalEugenol is naturally found in cloves, basil, and bay leaves. It is an aromatic oil used to add fragrance to a product. The scent of eugenol is described as "clove-like". Eugenol is a known EU allergen, meaning it causes contact allergies.
Studies show eugenol possesses antibacterial and antioxidant properties.
Besides cosmetics, eugenol is also added as a flavor in teas and cakes.
Learn more about EugenolReviews
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Where it's from
BioSilk is a American brand
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The data we've presented on this page has been verified by a member of the SkinSort Team.
Read more about us· Updated May 15, 2025 • Added by Maritake_N