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InventoryRef 3698127/06/2016

POTASSIUM HYDROXIDE

Potassium hydroxide

POTASSIUM HYDROXIDE is linked to 1 EU annex record on this page. Inventory note: III/15a, 15d.

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MarketEvidence statusRecordsSource language
European UnionEvidence linked
Restricted entry found
Open this evidence		1English and EU languages
Great BritainEvidence linked
Restricted
Open this evidence		2English
CanadaSource mapped
Official source mapped; ingredient rule not imported
0English and French
New ZealandEvidence linked
Restricted
Open this evidence		2English
ASEANEvidence linked
Restricted
Open this evidence		2English and national languages
ChinaSource mapped
Official source mapped; ingredient rule not imported
0Chinese with selected English material
JapanSource mapped
Official source mapped; ingredient rule not imported
0Japanese; official English translation available
South KoreaEvidence linked
Restricted
Open this evidence		1Korean with some English names
United StatesSource mapped
Official source mapped; ingredient rule not imported
0English
AustraliaSource mapped
Official source mapped; ingredient rule not imported
0English
BrazilSource mapped
Official source mapped; ingredient rule not imported
0Portuguese with INCI crosswalks
IndiaEvidence linked
Restricted
Open this evidence		2English and Hindi
Saudi ArabiaEvidence linked
Restricted
Open this evidence		2Arabic and English

Chemical identity and properties

PubChem 2D chemical structure for CAS 1310-58-3
CAS 1310-58-3PubChem CID 14797

Potassium Hydroxide

Potassium hydroxide is an alkali metal hydroxide. — ChEBI

IUPAC name
potassium hydroxide
Molecular formula
HKO
Molecular weight
56.106 g/mol
Exact mass
55.96644614 Da
Topological polar surface area
1.0 Ų
Hydrogen-bond donors
1
Hydrogen-bond acceptors
1
Covalent units
2
Defined stereocentres
0

Also known as

Caustic potashPotash lyePotassium hydrateHydroxyde de potassiumPotassaPotasse caustiqueCaustic-potashKali causticum
16 more reported names
Caswell No. 693Cyantek CC 723Potassium hydroxide (K(OH))KaliumhydroxidCCRIS 6569Potassio (idrossido di)Potassium (hydroxyde de)WZH3C48M4TEPA Pesticide Chemical Code 075602INS NO.525INS-525E-525CHEBI:32035KaliumhydroxydeRefChem:6672MIRACLE WATER 3 in 1
Open full PubChem recordPubChem annotations3D structure image
External database identifiers

Evidence from additional scientific databases

NIH PubChem PUG-View
Exact identifier match14797

Attributed physical-property, hazard, environmental and use annotations.

  • Autoignition Temperature: Not flammable (USCG, 1999) Source: CAMEO Chemicals
  • First Aid: (Act quickly]); EYES: flush with water for at least 15 min.; SKIN: flush with water, then rinse with dilute vinegar (acetic acid).; INGESTION: give water and milk. Do NOT induce vomiting. Call physician at once, even when injury seems to be slight. (USCG, 1999) Source: CAMEO Chemicals
  • First Aid: EYES: First check the victim for contact lenses and remove if present. Flush victim's eyes with water or normal saline solution for 20 to 30 minutes while simultaneously calling a hospital or poison control center. Do not put any ointments, oils, or medication in the victim's eyes without specific instructions from a physician. IMMEDIATELY transport the victim after flushing eyes to a hospital even if no symptoms (such as redness or irritation) develop.; SKIN: IMMEDIATELY flood affected skin with water while removing and isolating all contaminated clothing. Gently wash all affected skin areas thoroughly with soap and water. IMMEDIATELY call a hospital or poison control center even if no symptoms (such as redness or irritation) develop. IMMEDIATELY transport the victim to a hospital for treatment after washing the affected areas.; INHALATION: IMMEDIATELY leave the contaminated area; take deep breaths of fresh air. If symptoms (such as wheezing, coughing, shortness of breath, or burning in the mouth, throat, or chest) develop, call a physician and be prepared to transport the victim to a hospital. Provide proper respiratory protection to rescuers entering an unknown atmosphere. Whene Source: CAMEO Chemicals
  • ERG2024, Guide 154 (Potassium hydroxide, solution; Potassium hydroxide, solid): General First Aid:; · Call 911 or emergency medical service.; · Ensure that medical personnel are aware of the material(s) involved, take precautions to protect themselves and avoid contamination.; · Move victim to fresh air if it can be done safely.; · Administer oxygen if breathing is difficult.; · If victim is not breathing:; -- DO NOT perform mouth-to-mouth resuscitation; the victim may have ingested or inhaled the substance.; -- If equipped and pulse detected, wash face and mouth, then give artificial respiration using a proper respiratory medical device (bag-valve mask, pocket mask equipped with a one-way valve or other device).; -- If no pulse detected or no respiratory medical device available, provide continuous compressions. Conduct a pulse check every two minutes or monitor for any signs of spontaneous respirations.; · Remove and isolate contaminated clothing and shoes.; · For minor skin contact, avoid spreading material on unaffected skin.; · In case of contact with substance, remove immediately by flushing skin or eyes with running water for at least 20 minutes.; · For severe burns, immediate medical attention is required.; · Effects of exposure (inhalation, ingestion, Source: Emergency Response Guidebook (ERG)
  • ERG2024, Guide 154 (Potassium hydroxide, solid; Potassium hydroxide, solution): General First Aid:; · Call 911 or emergency medical service.; · Ensure that medical personnel are aware of the material(s) involved, take precautions to protect themselves and avoid contamination.; · Move victim to fresh air if it can be done safely.; · Administer oxygen if breathing is difficult.; · If victim is not breathing:; -- DO NOT perform mouth-to-mouth resuscitation; the victim may have ingested or inhaled the substance.; -- If equipped and pulse detected, wash face and mouth, then give artificial respiration using a proper respiratory medical device (bag-valve mask, pocket mask equipped with a one-way valve or other device).; -- If no pulse detected or no respiratory medical device available, provide continuous compressions. Conduct a pulse check every two minutes or monitor for any signs of spontaneous respirations.; · Remove and isolate contaminated clothing and shoes.; · For minor skin contact, avoid spreading material on unaffected skin.; · In case of contact with substance, remove immediately by flushing skin or eyes with running water for at least 20 minutes.; · For severe burns, immediate medical attention is required.; · Effects of exposure (inhalation, ingestion, Source: Emergency Response Guidebook (ERG)
  • ERG2024, Guide 154 (Caustic potash, solution; Caustic potash, solid): General First Aid:; · Call 911 or emergency medical service.; · Ensure that medical personnel are aware of the material(s) involved, take precautions to protect themselves and avoid contamination.; · Move victim to fresh air if it can be done safely.; · Administer oxygen if breathing is difficult.; · If victim is not breathing:; -- DO NOT perform mouth-to-mouth resuscitation; the victim may have ingested or inhaled the substance.; -- If equipped and pulse detected, wash face and mouth, then give artificial respiration using a proper respiratory medical device (bag-valve mask, pocket mask equipped with a one-way valve or other device).; -- If no pulse detected or no respiratory medical device available, provide continuous compressions. Conduct a pulse check every two minutes or monitor for any signs of spontaneous respirations.; · Remove and isolate contaminated clothing and shoes.; · For minor skin contact, avoid spreading material on unaffected skin.; · In case of contact with substance, remove immediately by flushing skin or eyes with running water for at least 20 minutes.; · For severe burns, immediate medical attention is required.; · Effects of exposure (inhalation, ingestion, Source: Emergency Response Guidebook (ERG)
  • First Aid: (General first aid procedures); Eye: Irrigate immediately - If this chemical contacts the eyes, immediately wash (irrigate) the eyes with large amounts of water, occasionally lifting the lower and upper lids. Get medical attention immediately.; Skin: Water flush immediately - If this chemical contacts the skin, immediately flush the contaminated skin with water. If this chemical penetrates the clothing, immediately remove the clothing and flush the skin with water. Get medical attention promptly.; Breathing: Respiratory support; Swallow: Medical attention immediately - If this chemical has been swallowed, get medical attention immediately. Source: The National Institute for Occupational Safety and Health (NIOSH)
  • Signal: Danger Source: Regulation (EC) No 1272/2008 of the European Parliament and of the Council
  • GHS Hazard Statements: H302: Harmful if swallowed [Warning Acute toxicity, oral]; H314: Causes severe skin burns and eye damage [Danger Skin corrosion/irritation] Source: Regulation (EC) No 1272/2008 of the European Parliament and of the Council
  • Precautionary Statement Codes: P260, P264, P270, P280, P301+P317, P301+P330+P331, P302+P361+P354, P304+P340, P305+P354+P338, P316, P321, P330, P363, P405, and P501 (click each P-code to see the statement) Source: Regulation (EC) No 1272/2008 of the European Parliament and of the Council
  • Note: This chemical does not meet GHS hazard criteria for < 0.1% (3 of 4709) of reports. Source: European Chemicals Agency (ECHA)
  • Signal: Danger Source: European Chemicals Agency (ECHA)
  • GHS Hazard Statements: H290 (20.9%): May be corrosive to metals [Warning Corrosive to Metals]; H302 (96.1%): Harmful if swallowed [Warning Acute toxicity, oral]; H314 (99.4%): Causes severe skin burns and eye damage [Danger Skin corrosion/irritation]; H318 (24.7%): Causes serious eye damage [Danger Serious eye damage/eye irritation] Source: European Chemicals Agency (ECHA)
  • Precautionary Statement Codes: P234, P260, P264, P264+P265, P270, P280, P301+P317, P301+P330+P331, P302+P361+P354, P304+P340, P305+P354+P338, P316, P317, P321, P330, P363, P390, P405, P406, and P501 (click each P-code to see the statement) Source: European Chemicals Agency (ECHA)
  • ECHA C&L Notifications Summary: Aggregated GHS information provided per 4709 reports by companies from 79 notifications to the ECHA C&L Inventory. Each notification may be associated with multiple companies.; Reported as not meeting GHS hazard criteria per 3 of 4709 reports by companies.; There are 78 notifications provided by 4706 of 4709 reports by companies with hazard statement code(s).; Information may vary between notifications depending on impurities, additives, and other factors. The percentage value in parenthesis indicates the notified classification ratio from companies that provide hazard codes. Only hazard codes with percentage values above 10% are shown. For more detailed information, please visit ECHA C&L website. Source: European Chemicals Agency (ECHA)
  • Signal: Danger Source: NITE-CMC
  • GHS Hazard Statements: H301: Toxic if swallowed [Danger Acute toxicity, oral]; H304: May be fatal if swallowed and enters airways [Danger Aspiration hazard]; H314: Causes severe skin burns and eye damage [Danger Skin corrosion/irritation]; H318: Causes serious eye damage [Danger Serious eye damage/eye irritation]; H370: Causes damage to organs [Danger Specific target organ toxicity, single exposure]; H372: Causes damage to organs through prolonged or repeated exposure [Danger Specific target organ toxicity, repeated exposure] Source: NITE-CMC
  • Precautionary Statement Codes: P260, P264, P264+P265, P270, P280, P301+P316, P301+P330+P331, P302+P361+P354, P304+P340, P305+P354+P338, P308+P316, P316, P317, P319, P321, P330, P331, P363, P405, and P501 (click each P-code to see the statement) Source: NITE-CMC
  • GHS Hazard Statements: H301: Toxic if swallowed [Danger Acute toxicity, oral]; H304: May be fatal if swallowed and enters airways [Danger Aspiration hazard]; H314: Causes severe skin burns and eye damage [Danger Skin corrosion/irritation]; H318: Causes serious eye damage [Danger Serious eye damage/eye irritation]; H370: Causes damage to organs [Danger Specific target organ toxicity, single exposure] Source: NITE-CMC
  • Cosmetic Ingredient Review Conclusion: The CIR Expert Panel concluded that ... Potassium Hydroxide is safe in hair straighteners and depilatories under conditions of recommended use; users should minimize skin contact. These ingredients are safe for all other present practices of use and concentration described in this safety assessment when formulated to be nonirritating. Source: Cosmetic Ingredient Review (CIR)
  • Cosmetic Ingredient Review Finding(s): Safe for use in cosmetics, with qualifications Source: Cosmetic Ingredient Review (CIR)
  • Toxicity Summary: IDENTIFICATION AND USE: Potassium hydroxide (KOH) is commercialized as a solid or as solutions with varying concentrations. It is used in soap manufacture; drain and pipeline cleaners; bleaching agents; manufacture of potassium carbonate and tetrapotassium pyrophosphate, an electrolyte in alkaline storage batteries and some fuel cells, absorbent for carbon dioxide and hydrogen sulfide; dyestuffs; liquid fertilizers; food additive; herbicides; electroplating; mercerizing; and paint removers. HUMAN EXPOSURE AND TOXICITY: Potassium hydroxide causes direct local effects on the skin, eyes and gastrointestinal tract after direct exposure. If KOH aerosols/mists occur, they will cause direct local effects on respiratory tract. Solutions with concentrations higher than 2% are corrosive, while concentrations of about 0.5 to about 2.0 % are irritating. The irritant effects are reported as coughing, wheezing, conjunctivitis, tearing, and irritation. Children may be accidentally exposed to commercial cleaning products. In a retrospective clinical study with 168 children after alkaline substance ingestion, 9 children (5.3%) developed gastric outlet obstruction. The fatal complications from an al Source: Hazardous Substances Data Bank (HSDB)
  • Consumer Uses: Solvent; Anti-adhesive/cohesive; Anti-freeze agent; Other; Lubricating agent; Processing aids not otherwise specified; Surfactant (surface active agent); Chemical reaction regulator; Fuel agents; pH regulating agent; Cleaning agent; Ion exchange agent; Not Known or Reasonably Ascertainable; Corrosion inhibitor; Soil amendments (fertilizers); Etching agent; Processing aids, specific to petroleum production; Intermediate Source: EPA Chemical Data Reporting (CDR)
  • Industry Uses: Ion exchange agent; Catalyst; Corrosion inhibitor; Not Known or Reasonably Ascertainable; Soil amendments (fertilizers); Cleaning agent; Absorbent; Oxidizing agent; Surface modifier; Processing aids, specific to petroleum production; Intermediate; Chelating agent; Etching agent; Adhesion/cohesion promoter; Freeze-thaw additive; Lubricating agent; Other; Flavoring and nutrient; Anti-adhesive/cohesive; Anti-freeze agent; Conductive agent; Fuel agents; pH regulating agent; Plating agent; Abrasives; Chemical reaction regulator; Semiconductor and photovoltaic agent; Surfactant (surface active agent); Processing aids not otherwise specified Source: EPA Chemical Data Reporting (CDR)
  • Cosmetic Ingredient Review Link: CIR ingredient: Potassium Hydroxide Source: Cosmetic Ingredient Review (CIR)
  • Sources/Uses: Used to make liquid soaps; it is also used in paint, varnish removers, and drain cleaners; it is used in electroplating, photoengraving, and lithography. [ACGIH] Used as a wet etchant in semiconductor manufacturing at standard concentrations of 50% or 10%; [CSH, p. 46] Source: Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
  • Industrial Processes with risk of exposure: Acid and Alkali Cleaning of Metals [Category: Clean]; Electroplating [Category: Plate]; Semiconductor Manufacturing [Category: Industry]; Battery Manufacturing [Category: Industry]; Photographic Processing [Category: Other] Source: Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
  • Activities with risk of exposure: Lithography printing [Category: Hobbies] Source: Haz-Map, Information on Hazardous Chemicals and Occupational Diseases
  • Uses: For potassium hydroxide (USEPA/OPP Pesticide Code: 075602) there are 0 labels match. /SRP: Not registered for current use in the U.S., but approved pesticide uses may change periodically and so federal, state and local authorities must be consulted for currently approved uses./ Source: Hazardous Substances Data Bank (HSDB)
  • Uses: The active ingredient is no longer contained in any registered pesticide products ... "cancelled." Source: Hazardous Substances Data Bank (HSDB)
  • Uses: Manufacturing liquid soap; mordant for wood; absorbing CO2; mercerizing cotton; print and varnish removers; electroplating, photoengraving and lithography; printing inks; in analytical chemistry for alkalimetric titrations; in organic synthesis. Pharmaceutic aid (alkalizer). Source: Hazardous Substances Data Bank (HSDB)
  • Uses: Soap manufacture, bleaching, manufacture of potassium carbonate and tetrapotassium pyrophosphate, electrolyte in alkaline storage batteries and some fuel cells, absorbent for carbon dioxide and hydrogen sulfide, dyestuffs, liquid fertilizers, food additive, herbicides, electroplating, mercerizing, paint removers, reagent. Source: Hazardous Substances Data Bank (HSDB)
  • Uses: For more Uses (Complete) data for POTASSIUM HYDROXIDE (10 total), please visit the HSDB record page. Source: Hazardous Substances Data Bank (HSDB)

Mapped by: Existing checksum-valid CAS to unique PubChem CID match. Retrieved: 2026-08-31. Open source record

Scientific classifications and hazard annotations provide context and do not replace the market-specific regulatory decision shown above.

Additional source coverage and match status
SourceResultChecked
NIH PubChem PUG-ViewExact match2026-08-31

A recorded no-match is useful evidence that the source was checked; it is not a claim that the substance does not exist elsewhere.

Retrieved from NIH PubChem on 2026-08-31 by checksum-valid CAS matching. Chemical properties do not replace the regulatory decision on this page.

Inventory details for POTASSIUM HYDROXIDE

INCI name

POTASSIUM HYDROXIDE

INN name

potassium hydroxide

Ph. Eur. name

kalii hydroxidum

Description

Potassium hydroxide

Record provenance

Inventory reference
36981
Imported identity
POTASSIUM HYDROXIDE
Source update
27/06/2016
European Commission CosIng source notes

Key data

CAS
1310-58-3
EC
215-181-3
Restriction
III/15a, 15d
Function
BUFFERING
Stabilising the pH of an aqueous medium in a narrow range even if an acid or base is added. Altering and/or maintaining a cosmetic product's pH at the desired level.

Official EU ingredient-name evidence

The ingredient name exactly matches the official 2025 EU glossary of common ingredient names.

#22655 · POTASSIUM HYDROXIDE

Ingredients with overlapping formulation functions

POTASSIUM BITARTRATEBUFFERING
POTASSIUM BORATEBUFFERING
POTASSIUM CARBONATEBUFFERING
POTASSIUM CITRATEBUFFERING, CHELATING
POTASSIUM LACTATEBUFFERING, HUMECTANT, SKIN CONDITIONING
POTASSIUM MAGNESIUM ASPARTATEBUFFERING, SKIN PROTECTING
POTASSIUM OXIDEBUFFERING
POTASSIUM PHOSPHATEBUFFERING

Additional official and scientific sources

11 external databases to check this identity in

Each link searches that source for this identity. What each source is, and its legal weight

ECHA CHEM / Information on chemicalsPubChem PUG RESTEU Safety Gate cosmetic product alertsECHA CHEMUS EPA CompToxCosmetic Ingredient Review safety assessmentsFDA Global Substance Registration SystemILO/WHO International Chemical Safety CardsJapan NITE-CHRIPNIOSH Pocket Guide to Chemical HazardsOECD eChemPortal

How POTASSIUM HYDROXIDE appears in the CosIng inventory

The CosIng inventory lists POTASSIUM HYDROXIDE as a cosmetic ingredient and this page links it to 1 annex record. The inventory entry captures names and identifiers, while the annex record shows where the substance is prohibited, restricted or positively listed in EU cosmetics law.

POTASSIUM HYDROXIDE is also tagged with 1 cosmetic function in the official data. Function labels describe intended use, but they do not replace regulatory review of linked annex records before formulation or labelling work.

Frequently asked questions

POTASSIUM HYDROXIDE appears in the EU CosIng inventory and has linked annex records. Check the annex records above for applicable restrictions, concentration limits and conditions of use. Annex II listing means prohibited; Annex III means restricted; Annexes IV, V and VI mean permitted under specified conditions.

The restriction field for POTASSIUM HYDROXIDE reads: "III/15a, 15d". This is the restriction note recorded in the CosIng inventory for this ingredient. For authoritative conditions and limits, always refer to the linked annex entries above.

According to the EU CosIng inventory, POTASSIUM HYDROXIDE carries the following function designation(s):

CAS 1310-58-3 may appear across multiple EU annex records. Viewing the CAS lookup page shows all Annex II–VI entries sharing this identifier, which is useful for identifying cross-annex regulatory status of the same chemical substance.
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Source note for POTASSIUM HYDROXIDE

This page combines the CosIng inventory entry for POTASSIUM HYDROXIDE with 1 linked Annex II–VI record from the local dataset built from public European Commission cosmetic ingredient materials.

Use this inventory page to research POTASSIUM HYDROXIDE and compare linked records, but verify restrictions and legal status against the current official source text and law before making regulatory decisions.

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