Kojic acid

  • 5-Hydroxy-2-hydroxymethyl-4-pyrone
  • 5-Hydroxy-2-hydroxymethyl-4H-pyran-4-one
  • 2-(Hydroxymethyl)-5-hydroxy-4H-pyran-4-one
Formula
C6H6O4
Structure
Description
White powder.
Uses
Converted to maltol and ethyl maltol, flavor-enhancing additives.

Registry Numbers and Inventories.
CAS
501-30-4
EC (EINECS/ELINCS)
207-922-4
S 22 36/37
RTECS
UQ0875000
RTECS class
Tumorigen; Drug; Mutagen
Merck
13,5334
Beilstein/Gmelin
120895
Beilstein Reference
5-18-01-00378
US TSCA
Listed
New Zealand
Listed

Properties.
Formula
C6H6O4
Formula mass
142.11
Melting point, °C
149 - 152
Boiling point, °C
323
Density
1.58 g/cm3
Solubility in water
Soluble
pKa/pKb
8.05 (pKa)
Partition coefficient, pKow
-2.45

Hazards and Protection.
Storage
Store in a cool, dry place. Store in a tightly closed container.
Handling
Wash thoroughly after handling. Remove contaminated clothing and wash before reuse. Use with adequate ventilation. Avoid contact with eyes, skin, and clothing. Keep container tightly closed. Avoid ingestion and inhalation. Use only in a chemical fume hood.
Protection
Eyes: Wear appropriate protective eyeglasses or chemical safety goggles as described by OSHA's eye and face protection regulations in 29 CFR 1910.133 or European Standard EN166. Skin: Wear appropriate protective gloves to prevent skin exposure. Clothing: Wear appropriate protective clothing to minimize contact with skin.
Respirators
A respiratory protection program that meets OSHA's 29 CFR 1910.134 and ANSI Z88.2 requirements or European Standard EN 149 must be followed whenever workplace conditions warrant a respirator's use. Wear a NIOSH/MSHA or European Standard EN 149 approved full-facepiece airline respirator in the positive pressure mode with emergency escape provisions.
Small spills/leaks
Clean up spills immediately, using the appropriate protective equipment. Sweep up, then place into a suitable container for disposal. Provide ventilation.
Disposal code
3
Stability
Stable under normal temperatures and pressures.
Incompatibilities
Oxidizing agents.
Decomposition
Carbon monoxide, carbon dioxide, acrid smoke and fumes.

Fire.
Fire fighting
Wear a self-contained breathing apparatus in pressure-demand, MSHA/NIOSH (approved or equivalent), and full protective gear. During a fire, irritating and highly toxic gases may be generated by thermal decomposition or combustion. To extinguish fire use water spray, dry chemical, carbon dioxide, or appropriate foam.
Health
0
 
Flammability
0
 
 
Reactivity
0
 

Health.
Exposure effects
   Ingestion
May cause irritation of the digestive tract. The toxicological properties of this substance have not been fully investigated.
   Inhalation
May cause respiratory tract irritation. The toxicological properties of this substance have not been fully investigated.
   Skin
May cause skin irritation.
   Eyes
May cause eye irritation.

First aid
 
   Ingestion
Never give anything by mouth to an unconscious person. Get medical aid. Do NOT induce vomiting. If conscious and alert, rinse mouth and drink 2-4 cupfuls of milk or water.
   Inhalation
Remove from exposure to fresh air immediately. If not breathing, give artificial respiration. If breathing is difficult, give oxygen. Get medical aid.
   Skin
Get medical aid. Flush skin with plenty of soap and water for at least 15 minutes while removing contaminated clothing and shoes. Wash clothing before reuse.
   Eyes
Flush eyes with plenty of water for at least 15 minutes, occasionally lifting the upper and lower eyelids. Get medical aid.

Transport.
HS Code
2932 99 95