Kiehl's Midnight Recovery Concentrate Serum With Botanical Oil Blend For Radiant Skin

DESCRIPTION

What It Does: Lightweight, stable emollient that solubilizes oil-soluble actives for excellent delivery without greasy feel.

Why It's Used: Universal lightweight emollient base and solubilizer for oil-soluble actives in serums and low-viscosity formulations where mineral oil or petrolatum would be too heavy.

How It Works: Medium-chain length provides ideal balance of spreading coefficient, penetration rate, and barrier-sealing properties. excellent solubilizer for vitamin e, retinoids, and other lipophilic actives.

Typically Found In: Serums,facial oils,sunscreens,anti-aging products,hair products

TECHNICAL DETAILS

Primary Category: Active ingredient – medium-chain triglyceride emollient

Secondary Functions: Active solubilizer,spreading agent

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 1%–50%

SOURCING & ETHICS

Vegan Status: Yes – from coconut/palm kernel oil

Halal Status: Yes

Source Notes: Fractionated by hydrolysis and re-esterification of coconut oil. only c8 and c10 fatty acids retained.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 1/5 – very low; medium-chain length generally non-comedogenic

Sensitivity Concerns: Non-irritating.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

Safety Profile: Excellent safety profile. ewg score: 1.

Works Well With: Humectants,ceramides,actives as carrier

Avoid Combining With: No significant incompatibilities

SCIENTIFIC NOTE

Mct oil's medium-chain length (c8/c10) provides superior oxidative stability vs longer polyunsaturated chains and better skin aesthetics (lighter, less greasy) vs longer chain emollients (c16/c18). excellent solubilizer for retinoic acid, tocopheryl esters, and other lipophilic actives.

Last Verified: Cosing database,cir safety assessment,ewg skin deep

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Provides the defining intense lemon-citrus fragrance note.

Why It's Used: The lemon scent compound – citral defines the fresh lemon scent in lemon essential oil and lemongrass with potent antimicrobial activity.

How It Works: Mixture of e-isomer (geranial) and z-isomer (neral). antimicrobial via michael addition to thiol enzymes. inhibits nf-kb for anti-inflammatory activity. antioxidant via allylic aldehyde.

Typically Found In: Citrus fragrances,antibacterial products,lemon-scented cosmetics

TECHNICAL DETAILS

Primary Category: Fragrance component – lemon aldehyde

Secondary Functions: Skin conditioning

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 0.001%–0.5%

SOURCING & ETHICS

Vegan Status: Yes – from lemon, lemongrass, melissa oils

Halal Status: Yes

Source Notes: Commercially produced for cosmetic use. verify vegan/halal status with supplier.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 0/5 – non-comedogenic

Sensitivity Concerns: Well-tolerated by most skin types.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

Safety Profile: Eu cosmetics regulation: declared fragrance allergen. high sensitisation potential from alpha,beta-unsaturated aldehyde structure. ifra strict limits.

Works Well With: Standard skincare actives

Avoid Combining With: No known significant incompatibilities

SCIENTIFIC NOTE

Citral's high sensitisation potential (llna ec3 ~0.11%) is a consequence of its alpha,beta-unsaturated aldehyde structure providing a highly reactive michael acceptor for skin protein covalent binding. the e/z mixture (geranial/neral) in natural citral means both isomers contribute to the sensitisation burden – explaining why lemongrass oil (very high citral content, ~60-80%) is one of the more common essential oil allergens.

Last Verified: Cosing database,ifra standards

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Provides soft, lasting rose-floral fragrance note.

Why It's Used: Essential rose fragrance monoterpene for lasting smooth floral notes in high-quality perfumery and cosmetic fragrances.

How It Works: Allylic alcohol monoterpene provides fixative property in fragrance blends. good skin substantivity for lasting scent. softer, rounder rose note vs geraniol's fresher character. natural in rose otto at 18-34%.

Typically Found In: Rose perfumes,floral fragrances,luxury skincare

TECHNICAL DETAILS

Primary Category: Fragrance component – monoterpene alcohol

Secondary Functions: Skin conditioning

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 0.001%–1%

SOURCING & ETHICS

Vegan Status: Yes – from rose, geranium, citronella oils

Halal Status: Yes

Source Notes: Commercially produced for cosmetic use. verify vegan/halal status with supplier.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 0/5 – non-comedogenic

Sensitivity Concerns: Well-tolerated by most skin types.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

Safety Profile: Eu cosmetics regulation: declared fragrance allergen. ifra guidelines apply.

Works Well With: Standard skincare actives

Avoid Combining With: No known significant incompatibilities

SCIENTIFIC NOTE

Citronellol's r-enantiomer (natural) vs s-enantiomer (synthetic) provide meaningfully different scent character – a remarkable demonstration of chiral scent discrimination by olfactory receptors. the (r) form provides the characteristic rose note while the (s) form has a distinctly different, less pleasant character. this enantiomeric scent difference means that the biological handedness of naturally-sourced vs racemic synthetic citronellol produces perceptibly different fragrance quality.

Last Verified: Cosing database,ifra standards

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Delivers characteristic cosmetic function at recommended use concentration.

Why It's Used: Selected for functional contribution and formulation compatibility supported by cosmetic science and regulatory safety data.

How It Works: Works through the mechanism of its molecular class — physicochemical or biological interaction with skin proteins, lipids, or receptors as documented in peer-reviewed cosmetic literature.

Typically Found In: Skin care formulations

TECHNICAL DETAILS

Primary Category: Active ingredient – cosmetic active

Secondary Functions: Skin conditioning

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 0.1%–10%

SOURCING & ETHICS

Vegan Status: Conditional

Halal Status: Yes

Source Notes: Commercially produced for cosmetic use. verify vegan/halal status with supplier.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 0/5 – non-comedogenic

Sensitivity Concerns: Well-tolerated by most skin types.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

Safety Profile: Good safety profile at recommended concentrations. ewg score: 1–2.

Works Well With: Standard skincare actives

Avoid Combining With: No known significant incompatibilities

SCIENTIFIC NOTE

Dicaprylyl carbonate has an established safety and efficacy profile within the cosmetic regulatory framework at standard use concentrations.

Last Verified: Cosing database,dicaprylyl carbonate technical literature

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Provides fresh rose-geranium floral scent with antimicrobial activity.

Why It's Used: The rose fragrance terpene – geraniol defines the fresh, sweet rose-geranium note found in more than 60 essential oils and is essential for recreating natural floral fragrance profiles.

How It Works: Monoterpene alcohol inhibits bacterial membrane integrity for antimicrobial activity. activates trpv1 for anti-nociception. inhibits nf-kb for anti-inflammatory activity. antioxidant via allylic radical scavenging.

Typically Found In: Rose-scented products,floral fragrances,natural cosmetics

TECHNICAL DETAILS

Primary Category: Fragrance component – acyclic monoterpene alcohol

Secondary Functions: Skin conditioning

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 0.001%–1%

SOURCING & ETHICS

Vegan Status: Yes – from rose, geranium, palmarosa oils

Halal Status: Yes

Source Notes: Commercially produced for cosmetic use. verify vegan/halal status with supplier.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 0/5 – non-comedogenic

Sensitivity Concerns: Well-tolerated by most skin types.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

Safety Profile: Eu cosmetics regulation: declared fragrance allergen. ifra guidelines apply.

Works Well With: Standard skincare actives

Avoid Combining With: No known significant incompatibilities

SCIENTIFIC NOTE

Geraniol's isomers (geraniol, nerol, citronellol) provide subtly different scent characters despite identical molecular formulae (c10h18o): geraniol provides the sweet, fresh rose note while its z-isomer nerol has a more delicate, neroli-like character. these isomeric scent differences arise from different spatial presentation of the hydroxyl and double bond groups to the olfactory receptor – demonstrating the extraordinary structural sensitivity of olfactory perception.

Last Verified: Cosing database,ifra standards

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Provides emollient conditioning from sc-compatible fatty acids and sterols with the lipid profile of lavandula hybrida determining barrier repair and skin feel properties.

Why It's Used: Lavandula hybrida oil is selected for the distinctive lipid profile of lavandula hybrida — the specific efa and sterol composition determines spreading speed, occlusion level, and sc barrier integration properties unique to this botanical source.

How It Works: Botanical lipid: fatty acid triglycerides → sc barrier emolliency; phytosterols → sc barrier lipid integration; efa → ceramide precursor; sterol esters → enhanced sc penetration.

Typically Found In: Skin care,barrier repair

TECHNICAL DETAILS

Primary Category: Active ingredient – antioxidant

Secondary Functions: Free radical scavenging,anti-aging

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 0.5%–30%

SOURCING & ETHICS

Vegan Status: Conditional

Halal Status: Conditional

Source Notes: Plant-derived extract or synthetic.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 0/5 – non-comedogenic

Sensitivity Concerns: Non-irritating; well-tolerated.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

Safety Profile: Excellent safety profile. ewg score: 1.

Works Well With: Vitamin c,vitamin e,ferulic acid,spf,other antioxidants

Avoid Combining With: No significant incompatibilities

SCIENTIFIC NOTE

Efa and sterol content should be verified — oxidative rancidity raises free radical load rather than reducing it.

Last Verified: Cosing database,lavandula hybrida botanical lipid review

Primary Sources: 2026-03-22

DESCRIPTION

What It Does: Provides the defining fresh citrus fragrance note alongside solvent and antimicrobial properties.

Why It's Used: The citrus industry's primary fragrance compound and the most abundant terpene in essential oils – limonene provides the clean, universally appealing fresh citrus scent character.

How It Works: D-limonene activates trpv1 mildly at high concentrations. antimicrobial via membrane disruption. solvent for oils and lipophilic compounds. cleaning via emulsification of lipid soils.

Typically Found In: Citrus-scented products,cleaning products,fragrance compounds

TECHNICAL DETAILS

Primary Category: Fragrance component – cyclic monoterpene

Secondary Functions: Skin conditioning

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 0.001%–3%

SOURCING & ETHICS

Vegan Status: Yes – from citrus peel essential oils

Halal Status: Yes

Source Notes: Commercially produced for cosmetic use. verify vegan/halal status with supplier.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 0/5 – non-comedogenic

Sensitivity Concerns: Well-tolerated by most skin types.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

Safety Profile: Eu cosmetics regulation: declared fragrance allergen. oxidises to sensitising compounds (limonene hydroperoxides) on air exposure – use with antioxidant stabilisers. ifra guidelines apply.

Works Well With: Standard skincare actives

Avoid Combining With: No known significant incompatibilities

SCIENTIFIC NOTE

Limonene's sensitisation risk arises not from limonene itself but from its autooxidation products (limonene-1,2-epoxide and limonene hydroperoxides) formed on air exposure. fresh limonene has low sensitisation potential, but air-oxidised limonene's hydroperoxide products are potent skin sensitisers. this explains why oxidation-stabilised formulations (with bht or other antioxidants) are required to manage limonene safety.

Last Verified: Cosing database,ifra standards,bråred christensson et al. limonene oxidation study

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Provides the most common natural floral-citrus fragrance note with additional anti-inflammatory properties.

Why It's Used: The most abundant fragrance terpene in nature – linalool forms the primary scent character of lavender, responsible for lavender's documented aromatherapy calming effects.

How It Works: Monoterpene alcohol activates gaba-a receptors for anti-anxiety activity (same receptor as benzodiazepines). inhibits glutamate-induced excitotoxicity. antimicrobial via membrane disruption. anti-inflammatory via nf-kb inhibition.

Typically Found In: Virtually all fragranced cosmetics

TECHNICAL DETAILS

Primary Category: Fragrance component – tertiary terpene alcohol

Secondary Functions: Skin conditioning

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 0.001%–3%

SOURCING & ETHICS

Vegan Status: Yes – from lavender, coriander, bergamot

Halal Status: Yes

Source Notes: Commercially produced for cosmetic use. verify vegan/halal status with supplier.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 0/5 – non-comedogenic

Sensitivity Concerns: Well-tolerated by most skin types.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

Safety Profile: Eu cosmetics regulation: declared fragrance allergen on label when >0.001% (leave-on) or >0.01% (rinse-off). ifra guidelines apply.

Works Well With: Standard skincare actives

Avoid Combining With: No known significant incompatibilities

SCIENTIFIC NOTE

Linalool's gaba-a receptor activation provides a pharmacological basis for lavender aromatherapy's documented anxiolytic effects. the same receptor modulation used by benzodiazepine drugs (such as diazepam) is activated by inhaled linalool vapor, providing receptor-mediated calming without the tolerance and dependence associated with pharmaceutical gaba-a modulators.

Last Verified: Cosing database,ifra standards,elisabetsky et al. linalool gaba study

Primary Sources: 2026-03-12

DESCRIPTION

What It Does: Nourishes and softens skin through its balanced fatty acid profile, while antioxidant compounds protect against oxidative skin damage.

Why It's Used: Plant oils provide physiologically compatible lipid structures that integrate into the skin barrier and deliver fat-soluble antioxidants directly to skin cells.

How It Works: Fatty acids integrate into stratum corneum lipid lamellae, reinforcing the lipid barrier. antioxidants (tocopherols, carotenoids, polyphenols) neutralize ros through electron donation or singlet oxygen quenching.

Typically Found In: Face oils,serums,moisturizers,hair treatments,body oils

TECHNICAL DETAILS

Primary Category: Plant oils

Secondary Functions: Emollient,antioxidant

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 0.5–30%

SOURCING & ETHICS

Vegan Status: Yes

Halal Status: Yes

Source Notes: Cold-pressed or solvent-extracted plant oil; no animal components.

SKIN COMPATIBILITY

Irritancy Rating: 1

Comedogenicity Rating: 2

Sensitivity Concerns: Low sensitization potential at recommended use concentrations.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

Safety Profile: Well-characterized cosmetic ingredient with established safety profile. generally non-irritating at typical use concentrations. suitable for leave-on and rinse-off cosmetics.

Works Well With: Vitamin e,ceramides,other plant oils,squalane

Avoid Combining With: Strong oxidizers (accelerate rancidity)

SCIENTIFIC NOTE

Vegetable oils are triglyceride matrices where the fatty acid composition determines skin compatibility, barrier function, and comedogenicity. oleic acid-rich oils (>60%) soften barrier lipids and enhance penetration; linoleic acid-rich oils reinforce ceramide-poor stratum corneum; saturated fatty acid-rich oils provide occlusion without skin penetration.

Last Verified: Cosing eu database; pcpc cosmetic ingredient safety reviews; aocs plant oil composition databases; fatty acid pharmacology reviews

Primary Sources: 2025-01-15

DESCRIPTION

What It Does: Provides antioxidant protection from reactive oxygen species, reduces inflammatory cytokine production in skin, and conditions skin through the plant's phytochemical complex.

Why It's Used: Natural origin narrative, traditional use heritage, and multi-functional phytochemical profile supporting concurrent skin care claims from one ingredient.

How It Works: Polyphenols, terpenoids, and alkaloids scavenge ros via h• donation, inhibit nf-kb or cox-2 inflammatory pathways, and interact with skin surface proteins for conditioning.

Typically Found In: Botanical skin care,natural products

TECHNICAL DETAILS

Primary Category: Active ingredient – antioxidant

Secondary Functions: Free radical scavenging,anti-aging

Application Areas:

Facial Skincare

Body Care

Hair Care

Beard Care

Color Cosmetics (Makeup)

Dietary/Oral Supplements

Typical Concentration Range: 0.1%–10%

SOURCING & ETHICS

Vegan Status: Conditional

Halal Status: Yes

Source Notes: Plant-derived extract or synthetic.

SKIN COMPATIBILITY

Irritancy Rating: 1/5 – very low

Comedogenicity Rating: 0/5 – non-comedogenic

Sensitivity Concerns: Non-irritating; well-tolerated.

Safe for Sensitive Skin: Yes

SAFETY & COMPATIBILITY

Safety Profile: Excellent safety profile. ewg score: 1.

Works Well With: Vitamin c,vitamin e,ferulic acid,spf,other antioxidants

Avoid Combining With: No significant incompatibilities

SCIENTIFIC NOTE

Plant secondary metabolites evolved as photoprotectants and antimicrobials — mechanisms directly applicable to cosmetic antioxidant and anti-inflammatory activity in human skin.

Last Verified: Cosing database,rosa canina fruit oil botanical review

Primary Sources: 2026-03-12