Hydroquinone
Agent Name
Hydroquinone
Alternative Name
Dihydroxybenzene
CAS Number
123-31-9
Formula
C6-H6-O2
Major Category
Other Classes
Synonyms
1,4-Benzenediol; 1,4-Dihydroxy-benzeen [Dutch]; 1,4-Dihydroxy-benzol [German]; 1,4-Dihydroxybenzen [Czech]; 1,4-Dihydroxybenzene; 1,4-Diidrobenzene [Italian]; 4-Hydroxyphenol; Arctuvin; Benzene, p-dihydroxy-; Benzohydroquinone; Benzoquinol; Black and White Bleaching Cream; Derma-Blanch; Diak 5; Eldopaque; Eldopaque Forte; Eldoquin; Eldoquin Forte; HE 5; Hidroquinone; Hydrochinon [Czech, Polish]; Hydroquinol; Hydroquinole; Hydroquinone; Idrochinone [Italian]; Phiaquin; Pyrogentistic acid; Quinol; Solaquin Forte; Tecquinol; Tenox HQ; Tequinol; p-Benzenediol; p-Dihydroxybenzene; p-Dioxybenzene; p-Hydroquinone; p-Hydroxyphenol; para-Dihydroxybenzene; para-Dioxybenzene; para-Hydroquinone; [ChemIDplus] UN2662
Category
Phenols
Description
Light-tan, light-gray, or colorless crystals; [NIOSH]
Sources/Uses
Used as a developer (photographic & lithographic), stabilizer in paints and oils, polymerization inhibitor, and chemical intermediate. [ACGIH] Used as a photo developer, oil and fat antioxidant, chemical intermediate, topical medication, and inhibitor of vinyl acetate and acrylic polymerization; [HSDB]
Comments
Workers exposed to high concentrations developed corneal ulcers. [ACGIH] Animals exposed to lethal doses have convulsions and methemoglobinemia. [HSDB] Can cause leukoderma (depigmentation of skin); [LaDou, p. 328] Allergic contact dermatitis in photographers; [Marks] Allergic contact dermatitis reported in developers of photographs, x-rays, and microfilms; also reported in dental technicians; [Kanerva, p. 1802] Severe eye irritant; [ICSC] Induces genetic damage in germ cells of humans or animals (3A); [MAK]
Biomedical References
Exposure Assessment
Skin Designation (ACGIH)
Insufficient data
TLV (ACGIH)
1 mg/m3
PEL (OSHA)
2 mg/m3
IDLH (NIOSH)
50 mg/m3
Excerpts from Documentation for IDLHs
Human data: It has been reported that 5 to 12 grams is the lethal oral dose [Zeidman and Deutel 1945]. [Note: An oral dose of 5 to 12 grams is equivalent to a worker being exposed to 3,333 to 8,000 mg/m3 for 30 minutes, assuming a breathing rate of 50 liters per minute and 100% absorption.]
Vapor Pressure
1.9E-05 mm Hg
Explanatory Notes
Flash point = 329 deg F; VP from HSDB;
Reference Link #2
NFPA
must be preheated
Adverse Effects
Skin Sensitizer
Yes
Methemoglobinemia
MetHgb is secondary toxic effect
IARC Carcinogen
Not classifiable
ACGIH Carcinogen
Confirmed Animal
Diseases, Processes, and Activities Linked to This Agent
Diseases
Occupational diseases associated with exposure to this agent:
Processes
Industrial Processes with risk of exposure: