Agent Name
Alternative Name
CAS Number
Major Category
Other Classes
o-Cresol formula graphical representation
1-Hydroxy-2-methylbenzene; 2-Cresol; 2-Hydroxy-1-methylbenzene; 2-Hydroxytoluene; 2-Methylphenol; Orthocresol; Phenol, 2-methyl-; o-Cresol; o-Cresylic acid; o-Hydroxytoluene; o-Kresol [German]; o-Methylphenol; o-Methylphenylol; o-Oxytoluene; o-Toluol; Cresol, o-; Cresol, o-isomer; Cresol, ortho-; [ChemIDplus] 2-Hydroxy-1-methylbenzene; ortho-Hydroxytoluene; [ICSC] OCRE; [NTP] UN2076; UN3455
Solid or liquid with a phenolic odor; Darkens with age and exposure to light and air; mp = 30 deg C; [Merck Index] Colorless solid; [ICSC] Colorless, yellow to yellowish-brown, or pink liquid; [CAMEO] White powder; [Sigma-Aldrich MSDS]
Used to make synthetic resins; Also used as an industrial solvent and in disinfectants and fungicides; [Merck Index] Used to make herbicides, pesticides, dyes, drugs, antioxidants, perfumes, and other chemicals; Also used as a food antioxidant, textile scouring agent, surfactant, metal cleaner, and ore flotation agent; Exposure may occur in the explosives, petroleum, photographic, paint, and agricultural industries; [HSDB] Used primarily as an intermediate; Other uses for o-cresol and cresol mixtures include cleaning compounds, degreasers, paints and paint strippers, adhesives, fiber treatment, wood preservatives, and cutting oils; [Reference #2] Used as flavoring agent or adjuvant; [FDA]
Causes burns; Inhalation may cause pulmonary edema; Short-term exposure may have effects on the CNS (lowering of consciousness) and blood (destruction of blood cells); Prolonged or repeated exposure may have effects on the nervous system (impaired functions) and blood (anemia); Can be absorbed through skin; [ICSC] May cause second degree skin burns after a few minutes contact; Effects of chronic exposure may include CNS damage, chronic gastritis, heart and brain lesions, and liver and kidney injury; [CHRIS] More toxic than the m-isomer and less toxic than the p-isomer; May cause skin sensitization; [HSDB] Safe when used as a flavoring agent in food; [JECFA] Causes burns; Inhalation may cause corrosive injuries to upper respiratory tract and lungs; Highly toxic by inhalation; Toxic by ingestion and skin absorption; Targets the CNS, lungs, liver, kidney, pancreas, spleen, and cardiovascular system; [Sigma-Aldrich MSDS] See "Cresol, all isomers." See "o-Cresol" and "p-Cresol."
Reference Link #1
Biomedical References

Exposure Assessment

Skin Designation (ACGIH)
20 mg/m3, inhalable fraction and vapor
22 mg/m3
Vapor Pressure
0.299 mm Hg
Odor Threshold Low
0.26 ppm
Odor Threshold High
0.65 ppm
Lethal Concentration
LC50 (rat) > 1,220 mg/m3/1hr
Explanatory Notes
Odor threshold low (detection) and high (recognition) from CHRIS; The Guide in the Emergency Response Guidebook is for "Cresols."
Reference Link #2
high ambient temp required

Adverse Effects

Hemolytic anemia
Toxic Pneumonitis
MetHgb is secondary toxic effect
Hepatoxic (a) from occupational exposure (secondary effect) or (b) in animal studies or in humans after ingestion
Skin burns
ACGIH Carcinogen
Not Classifiable

Diseases, Processes, and Activities Linked to This Agent