Agent Name

Sodium hydroxide

CAS Number




Major Category

Other Classes


Aetznatron; Ascarite; Caustic soda; Caustic soda, liquid; Collo-Grillrein; Collo-Tapetta; Fuers Rohr; Hydroxyde de sodium [French]; Lewis-red devil lye; Liquid-plumr; Natrium causticum; Natrium-hydroxid, reinstes; Natriumhydroxid [German]; Natriumhydroxyde [Dutch]; Plung; Rohrputz; Rohrreiniger Rofix; Soda lye; Soda, caustic; Soda, hydrate; Soda, kaustische; Sodio(idrossido di) [Italian]; Sodium hydrate; Sodium hydrate solution; Sodium hydroxide; Sodium hydroxide (Na(OH)); Sodium hydroxide (Na2(OH)2); Sodium hydroxide dimer; Sodium(hydroxyde de) [French]; White caustic; White caustic solution; [ChemIDplus] UN1823 (solid); UN1824 (solution);




Colorless to white, odorless solid (flakes, beads, granular form); [NIOSH] Deliquescent; [CHEMINFO]


Used to neutralize acids, produce sodium salts, hydrolyze fats to make soaps, and precipitate metals; large amounts are used in petroleum refining, rayon production, and rubber reclaiming; [Merck Index # 8627] Also used in metal cleaning, electroplating, processing cotton fabrics, and bleeching; [ATSDR Medical Management] Used in photography (developing bath); [] In semiconductor manufacturing, sodium hydroxide is used to "develop" the pattern in the photoresists and also as a wet echant. [CHS, p. 44-5] Caustic soda is used in hide preparation for leather production; [PMID 21938525]


Liquid causes second or third degree burns after short contact; [CHRIS] In studies using rabbits, instillation by oral intubation caused within 10 seconds: erosion into the stomach muscle with 12% solutions; perforation with 28% solutions; and no damage with 1% solutions. Application to the skin of a 5% solution caused severe necrosis after 4 hours. Application of a 1% solution to the eyes caused no damage if the eyes were immediately irrigated. [ACGIH] Solutions > 30% are highly corrosive to skin. [Quick CPC] Inhalation of the aerosol can cause pulmonary edema. [ICSC]

Reference Link

ATSDR Medical Management - Sodium hydroxide

Exposure Assessment
Skin Designation (ACGIH)

Insufficient data

Ceiling (ACGIH)

2 mg/m3


2 mg/m3


10 mg/m3

Excerpts from Documentation for IDLHs

Human data: Workplace concentrations ranging from 2 to 8 mg/m3 have been associated with irritation of the respiratory system [Ott et al. 1977].

Reference Link

ICSC: Sodium hydroxide

Adverse Effects
Toxic Pneumonitis



Skin Burns

Links to Other NLM Databases
Health Studies

Human Health Effects from Hazardous Substances Data Bank:

Toxicity Information


Chemical Information

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Biomedical References

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Related Information in HazMap

Industrial Processes with risk of exposure:


Activities with risk of exposure: