Also known as: KCl, [KCl], Potassium chloride (KCl), EC No.: 231-211-8, Caswell No. 686 (+15 more)
INCI: POTASSIUM HYDROXIDE
Potassium Hydroxide (CAS 7447-40-7) is a cosmetic cosmetic ingredient functioning as Strong alkali used in cuticle remover formulations at 2–5%. Dissolves dead. NOAEL 1820 mg/kg bw/day (cross-referenced against ToxValDB ECHA IUCLID); EU Regulation 1223/2009 status: restricted, max Regulated as alkaline agent; EU cosmetic regulations require pH and concentration control for alkaline products. Cuticle remover-specific formulations must be assessed for skin safety at use concentration/pH. Not for use on broken or irritated skin.. Industrial safety data is also available in the chemical safety dat
Strong alkali used in cuticle remover formulations at 2–5%. Dissolves dead cuticle tissue via alkaline hydrolysis of peptide bonds in the stratum corneum proteins of the cuticle. Caustic — strict pH control and precise concentration are essential for safe use. Also used as a pH adjuster in cosmetic formulations at much lower concentrations.
EU Max Conc.Regulated as alkaline agent; EU cosmetic regulations require pH and concentration control for alkaline products. Cuticle remover-specific formulations must be assessed for skin safety at use concentration/pH. Not for use on broken or irritated skin.
US US Statuspermitted
US NotesFDA GRAS for direct food use under 21 CFR 184.1631. No separate cosmetic approval system; cosmetic use governed by general FD&C Act safety provisions. CIR Expert Panel (2021, Int J Toxicol 40(2_suppl):16S-35S) concluded safe as used when formulated to be non-irritating. Not a sunscreen active.
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Safety Data
Margin of Safety, dermal absorption, and sensitization profile summaries for Potassium Hydroxide.
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Toxicological Studies
4 study endpoints found for Potassium Hydroxide. 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
195 mg/kg bw/day
oral
dog
Short Term Toxicity
COSMOS_DB
NOAEL
235 mg/kg bw/day
oral
mouse
Developmental
COSMOS_DB
NOAEL
310 mg/kg bw/day
oral
rat
Developmental
COSMOS_DB
NOAEL
=310 mg/kg bw/day
oral
Rat
developmental
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 and respiratory tract. Ingestion of large amounts could cause effects on the cardiovascular system. This may result in cardiac dysrhythmia.
Routes of Exposure
The substance can be absorbed into the body by ingestion.
Pre-Calculated Safety Assessment
Pre-calculated NOAEL → SED → MoS audit trail for Potassium Hydroxide across SCCS product categories, with measured dermal absorption where available.
EPA ToxValDB — Toxicity Values
6 toxicity values from EPA ToxValDB (aggregated from CCTE, HPV, ToxRefDB, IRIS, and other regulatory dossiers).
Endpoint
Value
Species
Route
Duration
Source
LEL
=40 mg/kg-day
Human
oral
short-term
EFSA
NOAEL
=310 mg/kg-day
Rat
oral
-
ECHA IUCLID
NOAEL
=310 mg/kg-day
Rat
oral
-
ECHA IUCLID
NOAEL
>141.96 mg/kg-day
Rat
oral
chronic
ECHA IUCLID
LD50
=1500 mg/kg
Mouse
oral
-
ChemIDplus
LD50
=2600 mg/kg
Rat
oral
-
ChemIDplus
ECHA REACH Registration
European Chemicals Agency REACH dossier and Substances of Very High Concern listing.
Registration Type
Full
Tonnage Band
10,000 - 100,000 tonnes
Substance Type
SUBSTANCE
SVHC Candidate
No
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
AU
restricted
-
specific uses
Additional Ingredient Properties
5 property records from structured ingredient metadata.
Potassium Hydroxide has a safety rating of "MODERATE" in our database. EU status: restricted. US status: permitted. 4 toxicological study endpoint(s) are available in our database.
Is Potassium Hydroxide allowed in the EU?
Potassium Hydroxide EU regulatory status: restricted. Maximum allowed concentration: Regulated as alkaline agent; EU cosmetic regulations require pH and concentration control for alkaline products. Cuticle remover-specific formulations must be assessed for skin safety at use concentration/pH. Not for use on broken or irritated skin.. This is based on EU Regulation 1223/2009 and its amendments.
What does Potassium Hydroxide do in cosmetics?
Potassium Hydroxide functions as: Strong alkali used in cuticle remover formulations at 2–5%. Dissolves dead cuticle tissue via alkaline hydrolysis of peptide bonds in the stratum corneum proteins of the cuticle. Caustic — strict pH control and precise concentration are essential for safe use. Also used as a pH adjuster in cosmetic formulations at much lower concentrations.. It is classified as a cosmetic ingredient in our database. CAS number: 7447-40-7.
What is the NOAEL for Potassium Hydroxide?
The NOAEL (No Observed Adverse Effect Level) for Potassium Hydroxide is 195 mg/kg bw/day based on a Short Term Toxicity study via oral route in dog. A total of 4 study endpoints are available. Source: COSMOS_DB.
Is Potassium Hydroxide used outside cosmetics?
Potassium Hydroxide 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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