Hydroquinone

Melting point :172-175 °C(lit.)
Boiling point :285 °C(lit.)
Density :1.32
bulk density :600kg/m3
vapor density :3.81 (vs air)
vapor pressure :1 mm Hg ( 132 °C)
refractive index :1.6320
Flash point :165 °C
storage temp. :Store below +30°C.
solubility :H₂O: 50 mg/mL, clear
pka :10.35(at 20℃)
form :Needle-Like Crystals or Crystalline Powder
color :White to off-white
Odor :odorless
biological source :synthetic
Water Solubility :70 g/L (20 ºC)
Sensitive :Air & Light Sensitive
Merck :14,4808
BRN :605970
Henry's Law Constant :(x 10^-9 atmm³/mol): <2.07 at 20 °C (approximate - calculated from water solubility and vapor pressure)
Exposure limits :NIOSH REL: 15-min ceiling 2, IDLH 50; OSHA PEL: TWA 2; ACGIH TLV: TWA 2 (adopted).
Stability :Stable. Combustible. Incompatible with strong oxidizing agents, strong bases, oxygen, ferric salts. Light and air-sensitive. Discolours in air.
Cosmetics Ingredients Functions :FRAGRANCE
HAIR DYEING
REDUCING
ANTIOXIDANT
BLEACHING Cosmetic Ingredient Review (CIR) :Hydroquinone (123-31-9)
InChI :1S/C6H6O2/c7-5-1-2-6(8)4-3-5/h1-4,7-8H
InChIKey :QIGBRXMKCJKVMJ-UHFFFAOYSA-N
SMILES :Oc1ccc(O)cc1
LogP :0.59 at 20℃
CAS DataBase Reference :123-31-9(CAS DataBase Reference)
IARC :3 (Vol. 15, Sup 7, 71) 1999
NIST Chemistry Reference :Hydroquinone(123-31-9)
EPA Substance Registry System :Hydroquinone (123-31-9)

Symbol(GHS):
Signal word:	Danger
Hazard statements:	Code Hazard statements Hazard class Category Signal word Pictogram P-Codes H302 Harmful if swallowed Acute toxicity,oral Category 4 Warning P264, P270, P301+P312, P330, P501 H315 Causes skin irritation Skin corrosion/irritation Category 2 Warning P264, P280, P302+P352, P321,P332+P313, P362 H317 May cause an allergic skin reaction Sensitisation, Skin Category 1 Warning P261, P272, P280, P302+P352,P333+P313, P321, P363, P501 H318 Causes serious eye damage Serious eye damage/eye irritation Category 1 Danger P280, P305+P351+P338, P310 H341 Suspected of causing genetic defects Germ cell mutagenicity Category 2 Warning P201,P202, P281, P308+P313, P405,P501 H351 Suspected of causing cancer Carcinogenicity Category 2 Warning P201, P202, P281, P308+P313, P405,P501 H370 Causes damage to organs Specific target organ toxicity, single exposure Category 1 Danger P260, P264, P270, P307+P311, P321,P405, P501 H372 Causes damage to organs through prolonged or repeated exposure Specific target organ toxicity, repeated exposure Category 1 Danger P260, P264, P270, P314, P501 H373 May cause damage to organs through prolonged or repeated exposure Specific target organ toxicity, repeated exposure Category 2 Warning P260, P314, P501 H410 Very toxic to aquatic life with long lasting effects Hazardous to the aquatic environment, long-term hazard Category 1 Warning P273, P391, P501
Precautionary statements:	P201 Obtain special instructions before use. P202 Do not handle until all safety precautions have been read and understood. P260 Do not breathe dust/fume/gas/mist/vapours/spray. P264 Wash hands thoroughly after handling. P264 Wash skin thouroughly after handling. P270 Do not eat, drink or smoke when using this product. P272 Contaminated work clothing should not be allowed out of the workplace. P273 Avoid release to the environment. P280 Wear protective gloves/protective clothing/eye protection/face protection. P302+P352 IF ON SKIN: wash with plenty of soap and water. P333+P313 IF SKIN irritation or rash occurs: Get medical advice/attention. P391 Collect spillage. Hazardous to the aquatic environment P405 Store locked up. P501 Dispose of contents/container to..…