Is Sulfur safe in cosmetics?
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.
Sulfur
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.
View industrial chemical safety profile for CAS 7704-34-9 →
Auto-generated CPSR Part A draft with source citations
Function
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
Safety Rating
GOOD
Regulatory Status
EU EU Status
permitted
US US Status
permitted
US Notes
FDA 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.
For full compliance data across multiple jurisdictions, use the Substance Compliance tool.
Safety Data
Margin of Safety, dermal absorption, and sensitization profile summaries for Sulfur.
Calculate MoS for your specific formulation with the MoS Calculator.
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 | ToxValDB_ECHA_IUCLID |
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
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
- H315 Causes 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 |
Additional Ingredient Properties
7 property records from structured ingredient metadata.
concentration
{"min_concentration_pct": "3.0", "max_concentration_pct": "10.0", "typical_concentration_pct": "8.0", "product_type": "Mask", "function_at_concentration": "Anti-acne, oil control", "source": "FDA OTC Monograph"}
dermal_absorption
{"molecular_weight_da": "32.1", "skin_penetration_level": "surface", "penetration_depth": "stratum corneum", "absorption_pct": "0.5-2", "systemic_absorption": "minimal", "penetration_enhancer": "no", "occlusion_effect": "no", "vehicle_dependent": "yes", "skin_barrier_effect": "neutral", "bioavailability_topical_pct": "0.2-1", "safety_margin_factor": "minimal", "source": "CIR"}
exfoliant
{"cas_number": "7704-34-9", "ingredient_class": "keratolytic", "chemical_subclass": "sulfur_compound", "molecular_weight_Da": "32.07", "pH_dependent_activity": "no", "penetration_depth": "stratum_corneum", "mechanism_of_action": "keratin_dissolution", "target_bonds": "disulfide bonds", "onset_of_action": "hours", "peak_effect_timeline": "2-4 weeks", "cell_turnover_increase_pct": "15-20%", "comedol…
interactions
{"ingredient_2": "Salicylic Acid", "interaction_type": "synergistic", "severity": "caution", "effect": "Enhanced acne treatment but very drying", "recommendation": "Effective for resistant acne; buffer with hydrators", "data_source": "Formulation science literature, dermatological research, cosmetic chemistry best practices", "last_updated": "2026-03-05"}
microbiome_impact
{"microbiome_effect": "mixed", "prebiotic": "no", "probiotic_compatible": "limited", "antimicrobial_spectrum": "selective", "preservative_effect_on_microbiome": "Keratolytic; antimicrobial; reduces C. acnes; moderate disruption", "skin_flora_disruption": "moderate", "gut_microbiome_risk": "low", "microbiome_recovery_time": "7-14 days", "selective_antimicrobial": "yes", "beneficial_bacteria_support…
pediatric_safety
{"safe_for_newborn_0_6m": "caution", "safe_for_infant_6_12m": "caution", "safe_for_toddler_1_3y": "yes", "safe_for_child_3_12y": "yes", "safe_for_teen_12_18y": "yes", "pediatric_max_concentration_pct": "3.0", "adult_max_concentration_pct": "10.0", "pediatric_dermal_absorption_factor": "low", "immature_skin_barrier_risk": "low", "oral_ingestion_risk": "low", "eye_irritation_risk": "low", "diaper_ar…
uv_stability
{"uv_stable": "yes", "uv_degradation_rate": "stable", "photosensitizer": "no", "phototoxic": "no", "photoallergic": "no", "requires_uv_protection_packaging": "no", "color_change_uv": "no", "odor_change_uv": "no", "efficacy_loss_uv_pct": "0", "spf_contribution": "no", "uva_protection": "no", "uvb_protection": "no", "photostable_sunscreen": "no", "boost_spf_of_others": "no", "antioxidant_under_uv": …
Function Categories & List Membership
Cosmetic/Chemical Function Categories
Alloying element
Anti-dandruff
Anti-static agent
Binder
Biocide
Catalyst
Chemical reaction regulator
Degradant/impurity
Hardener
No specific technical function
Regulatory List Membership (2)
EU Regulated in Personal Care
FDA Indirect Food Contact Additives
Expert Verdict
Expert safety assessment and concern-level summary for Sulfur.
Regulatory Flags
skin-irritant
keratolytic
otc-drug-us
fda-grase
odor-concern
anti-acne
anti-dandruff
fda-deferred-cir
NOAEL Studies Summary
View details ->Public NOAEL study rows linked to Sulfur by CAS number or substance name.
Studies
1
Lowest NOAEL
400 mg/kg bw/day
Highest NOAEL
400 mg/kg bw/day
ToxValDB_ECHA_IUCLID
Known Synonyms
Aquilite
Caswell No. 812
Colloidal-S
Collokit
Corosul D and S
EINECS 231-722-6
EPA Pesticide Chemical Code 077501
Flour sulphur
Ground vocle sulfur
Kolloidschwefel 95
Kolofog
Kolospray
Kristex
Magnetic 70, 90, and 95
Microflotox
Netzschwefel
NSC 403664
Polsulkol extra
Rc-schwefel extra
Sperlox-S
Chemical Function
Biocide
Anti-static agent
Softener and conditioner
Pharmaceutical
Anti-dandruff
Regulatory Lists
detected; Europe; Home maintenance - caulk/sealant
active_ingredient; Pesticides
active_ingredient; agricultural; applied; Pesticides
active_ingredient; agricultural; applied; Pesticides
active_ingredient; Pesticides
active_ingredient; Pesticides
active_ingredient; Pesticides
active_ingredient; Pesticides
active_ingredient; Pesticides
active_ingredient; Pesticides
active_ingredient; Pesticides
active_ingredient; Pesticides
active_ingredient; Pesticides
active_ingredient; Pesticides
active_ingredient; Pesticides
active_ingredient; Pesticides
active_ingredient; Pesticides
active_ingredient; Pesticides
Australian Status
AICIS status: listed
Cross-Vertical Safety Context
Same-CAS public records found in pharmaceutical data.
SOURCE
ChEMBL / DrugCentral / FAERS
DB_PHARMA CAS match
Pharmaceutical Data
Same-CAS rows from the pharmaceutical spoke database.
Compound
SULFUR
ChEMBL ID
CHEMBL1235452
Max Phase
4
Adverse Event Associations
105
Frequently Asked Questions
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: ToxValDB_ECHA_IUCLID.
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
Check Sulfur compliance across multiple jurisdictions:
Ingredient Decoder
Paste a full ingredient list for instant analysis
82 Allergen Checker
Check for EU declarable fragrance allergens
Substance Compliance
Check compliance across multiple jurisdictions
MoS Calculator
Calculate Margin of Safety using SCCS methodology
Heavy Metal Limits
Compare limits across jurisdictions
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