Also known as: Aquilite, Caswell No. 812, Colloidal-S, Collokit, Corosul D and S (+15 more)
INCI: SULFUR
Sulfur (CAS 7704-34-9) is a cosmetic active ingredient functioning as Keratolytic; antimicrobial; antifungal; sebum regulator; acne-control active;. NOAEL 200 mg/kg bw/day (cross-referenced against ToxValDB ECHA IUCLID); EU Regulation 1223/2009 status: permitted. Industrial safety data is also available in the chemical safety database. Same-CAS public records also appear in industrial chemical safety and pharmaceutical data.
Keratolytic; antimicrobial; antifungal; sebum regulator; acne-control active; structurally critical for keratin disulfide bonds in hair and nail; traditional balneotherapy active for psoriasis and atopic dermatitis
Editorial assessment
GOOD
Preliminary editorial note — not a computed safety verdict.
US NotesFDA GRAS OTC drug: acne treatment 3-10% standalone (21 CFR 333.310(e)) or 3-8% with resorcinol 2%; dandruff/seborrheic dermatitis 2-5% (OTC Monograph M032). Permitted combinations: resorcinol 2%, resorcinol monoacetate 3%, salicylic acid 1.8-3%. CIR Expert Panel deferred evaluation to FDA OTC drug assessment.
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Safety Data
Margin of Safety, dermal absorption, and sensitization profile summaries for Sulfur.
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Toxicological Studies
1 study endpoint found for Sulfur. NOAEL (No Observed Adverse Effect Level) values are used to calculate the Margin of Safety per SCCS methodology.
Endpoint
Value
Route
Species
Study Type
Source
NOAEL
=400 mg/kg bw/day
dermal
Rat
short-term
ECHA
GHS Hazard Classification
Globally Harmonized System classification per ECHA C&L inventory and ILO/WHO International Chemical Safety Cards.
Short-term Exposure Effects
The substance is irritating to the eyes, skin and respiratory tract. Inhalation of the powder may cause inflammation of the nose and respiratory tract.
Long-term Exposure Effects
Repeated or prolonged contact with skin may cause dermatitis. The substance may have effects on the respiratory tract. This may result in chronic bronchitis.
Routes of Exposure
The substance can be absorbed into the body by inhalation and by ingestion.
Pre-Calculated Safety Assessment
Pre-calculated NOAEL → SED → MoS audit trail for Sulfur across SCCS product categories, with measured dermal absorption where available.
Dermal Penetration Profile
Skin absorption and penetration characteristics of Sulfur, relevant to systemic exposure and MoS calculations.
Absorption %
0.5-2%
Penetration Level
surface
Penetration Depth
stratum corneum
Molecular Weight
32.1 Da
Log P
n/a
Systemic Absorption
minimal
Topical Bioavailability
0.2-1%
Safety Margin Factor
minimal
Vehicle Dependent
Yes — absorption varies by formulation
Source: CIR Expert Panel
EU CLP Annex VI Harmonized Classification
Legally binding harmonized classification per Regulation (EC) No 1272/2008 (CLP) Annex VI.
Signal Word
Warning
Pictograms
Harmful / Irritant
Hazard Class and Category
Skin Irrit. 2
Hazard Statements
H315Causes skin irritation
Inserted via ATP: ATP22
ECHA REACH Registration
European Chemicals Agency REACH dossier and Substances of Very High Concern listing.
Registration Type
Full
Tonnage Band
1,000,000 - 10,000,000 tonnes
Substance Type
SUBSTANCE; GROUP
SVHC Candidate
No
Hazard classification:Restricted (Annex XVII)
Expanded Jurisdictional Detail
Additional regulatory detail beyond the 7-jurisdiction summary: Saudi SFDA, Korea MFDS, ASEAN ACD, Japan/Korea, Brazil/India, and cross-jurisdictional restriction entries.
Additional Jurisdictional Restrictions (1)
Jurisdiction
Status
Max %
Product Type
BR
restricted
5 (anti-dandruff) / 10 (anti-acne)
a) Anti-dandruff: 5%; b) Anti-acne: 10%; external use only
Function Categories & List Membership
Cosmetic/Chemical Function Categories
Alloying elementAnti-dandruffAnti-static agentBinderBiocideCatalystChemical reaction regulatorDegradant/impurityHardenerNo specific technical function
Regulatory List Membership (2)
EU Regulated in Personal CareFDA Indirect Food Contact Additives
Editorial summary
Preliminary editorial summary for Sulfur — not a computed safety verdict. See the sourced toxicological data above.
Sulfur has a safety rating of "GOOD" in our database. EU status: permitted. US status: permitted. 1 toxicological study endpoint(s) are available in our database.
Is Sulfur allowed in the EU?
Sulfur EU regulatory status: permitted. This is based on EU Regulation 1223/2009 and its amendments.
What does Sulfur do in cosmetics?
Sulfur functions as: Keratolytic; antimicrobial; antifungal; sebum regulator; acne-control active; structurally critical for keratin disulfide bonds in hair and nail; traditional balneotherapy active for psoriasis and atopic dermatitis. It is classified as a Active Ingredient in our database. CAS number: 7704-34-9.
What is the NOAEL for Sulfur?
The NOAEL (No Observed Adverse Effect Level) for Sulfur is =400 mg/kg bw/day based on a short-term study via dermal route in Rat. Source: ECHA.
Is Sulfur used outside cosmetics?
Sulfur also appears in industrial chemical safety and pharmaceutical data. The cross-vertical cards on this page render same-CAS public rows from the matched databases.
Compliance Tools
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