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Potassium hydroxide

RTECS #
TT2100000
CAS #
1310-58-3
See: NMAM or OSHA Methods
Updated
March 2018
Molecular Weight
56.11
Molecular Formula
HKO
Synonyms
Caustic potash
Hydroxyde de potassium (French)
Kaliumhydroxid (German)
Kaliumhydroxyde (Dutch)
LYE
Potassa
Potasse caustique (French)
Potassio (idrossido di) (Italian)
Potassium (hydroxyde de) (French)
Potassium hydrate
Potassium hydroxide (ACGIH)

Skin and Eye Irritation and References

Route/OrganismDoseEffectReference
eye /rabbit 1 mg/24H rinse moderateTXAPA9 32,239,1975
skin /guinea pig 50 mg/24H severeTXAPA9 31,481,1975
skin /human 50 mg/24H severeTXAPA9 31,481,1975
skin /rabbit 50 mg/24H severeTXAPA9 31,481,1975

Mutation Data and Reference

System TestRoute/Organism/TissueDoseReference
Cytogenetic AnalysisAscites tumor/rat1800 mg/kgGANNA2 54,155,1963
Cytogenetic Analysisovary/hamster12 mmol/LMUREAV 225,55,1989

Acute Toxicity Data and References

Route/OrganismDoseEffectReference
In Vitro/Human, skin Inhibitor Concentration Low: 20 mmol/LNutritional and Gross Metabolic: Changes in: CaTIVIEQ 27,402,2013
In Vitro/Human, skin Inhibitor Concentration Low: 5 pph/1HIn Vitro Toxicity Studies: Cell viability (mitochondrial reductase assays): MTT, XTT, MTS, WSTs assays etc.TIVIEQ 28,616,2014
In Vitro/Human, skin Inhibitor Concentration Low: 10 pph/3MIn Vitro Toxicity Studies: Cell viability (mitochondrial reductase assays): MTT, XTT, MTS, WSTs assays etc.TIVIEQ 28,616,2014
In Vitro/Human, skin Inhibitor Concentration Low: 47 µL/well/45MIn Vitro Toxicity Studies: Cell viability (mitochondrial reductase assays): MTT, XTT, MTS, WSTs assays etc.TIVIEQ 28,742,2014
oral/rat lethal dose (50 percent kill): 273 mg/kgFAATDF 8,97,1987

Reviews

OrganizationStandardReference
American Conference of Governmental Industrial Hygienists (ACGIH)Threshold Limit Value-ceiling concentration 2 mg/m3DTLVS* TLV/BEI,2013
TOXICOLOGY REVIEWARTODN 39,299,1978
TOXICOLOGY REVIEWHUTOX* -,671,1996
TOXICOLOGY REVIEWHUTOX* -,683,1996

Standards and Regulations

OrganizationStandardReference
Environmental Protection Agency (EPA) Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) 1988 PESTICIDE SUBJECT TO REGISTRATION OR RE-REGISTRATIONFEREAC 54,7740,1989
Environmental Protection Agency (EPA) Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) 1998 STATUS OF PESTICIDESCancelledRBREV* -,326,1998
Occupational Exposure Limit IN ARGENTINA, BULGARIA, COLOMBIA, JORDAN check ACGIH TLV;
Occupational Exposure Limit IN SINGAPORE, VIETNAM check ACGIH TLV
Occupational Exposure Limit-AUSTRALIAceiling concentration 2 mg/m3, JUL2008
Occupational Exposure Limit-AUSTRIAMAK-TMW 2 mg/m3, inhal, 2007
Occupational Exposure Limit-BELGIUMshort term exposure limit 2 mg/m3, MAR2002
Occupational Exposure Limit-DENMARKceiling concentration 2 mg/m3, MAY2011
Occupational Exposure Limit-FINLANDceiling concentration 2 mg/m3, NOV2011
Occupational Exposure Limit-FRANCEVLE 2 mg/m3, FEB2006
Occupational Exposure Limit-HUNGARYtime-weighted average 2 mg/m3, short term exposure limit 2 mg/m3, SEP2000
Occupational Exposure Limit-ICELANDshort term exposure limit 2 mg/m3, NOV2011
Occupational Exposure Limit-JAPANceiling concentration 2 mg/m3, MAY2012
Occupational Exposure Limit-KOREAceiling concentration 2 mg/m3, 2006
Occupational Exposure Limit-NEW ZEALANDceiling concentration 2 mg/m3, JAN2002
Occupational Exposure Limit-NORWAYtime-weighted average 2 mg/m3, JAN1999
Occupational Exposure Limit-PERUshort term exposure limit 2 mg/m3, JUL2005
Occupational Exposure Limit-SWEDENtime-weighted average 1 mg/m3;short term exposure limit 2 mg/m3, (inhal. dust), JUN2005
Occupational Exposure Limit-SWITZERLANDMAK-week 2 mg/m3, inhal, JAN2011
Occupational Exposure Limit-THE NETHERLANDSMAC-C 2 mg/m3, 2003
Occupational Exposure Limit-UNITED KINGDOMshort term exposure limit 2 mg/m3, OCT2007

NIOSH Documentation and Surveillance

OrganizationStandardReference
National Institute for Occupational Safety and Health (NIOSH) Recommended Exposure Level TO POTASSIUM HYDROXIDE-airceiling concentration 2 mg/m3NIOSH* DHHS #92-100,1992
National Occupational Exposure Survey 1983Hazard Code X3783; Number of Industries 11; Total Number of Facilities 543; Number of Occupations 16; Total Number of Employees Exposed 6722; Total Number of Female Employees Exposed 2651
National Occupational Exposure Survey 1983Hazard Code 60440; Number of Industries 346; Total Number of Facilities 74278; Number of Occupations 221; Total Number of Employees Exposed 1959889; Total Number of Female Employees Exposed 797390
National Occupational Hazard Survey 1974Hazard Code 60440; Number of Industries 340; Total Number of Facilities 80620; Number of Occupations 181; Total Number of Employees Exposed 1081553

Status in Federal Agencies

OrganizationReference
EPA TSCA Section 8(b) CHEMICAL INVENTORY
EPA TSCA Section 8(e) Risk Notification, 8EHQ-0892-9197
EPA TSCA TEST SUBMISSION (TSCATS) DATA BASE, JANUARY 2001
NIOSH Analytical Method, 1994: Alkaline dusts, 7401
Page last reviewed: November 16, 2018