Natural Yellow 23

  • Chrysophanic acid
  • Chrysophanol
  • Turkey Rhubarb
  • 3-Methylchrysazin
  • 2-Methyl-4,5-dihydroxyanthraquinone
  • 1,8-Dihydroxy-3-methyl-9,10-anthracenedione
Formula
C15H10O4
Structure
Description
Golden yellow plates or brown powder. Pale yellow aqueous solutions turn red on addition of alkali. Solutions in concentrated sulfuric acid are red.
Uses
Dye.

Registry Numbers and Inventories.
CAS
481-74-3
EC (EINECS/ELINCS)
207-572-2
RTECS
CB6725000
RTECS class
Mutagen
Merck
12,2318
Beilstein/Gmelin
1252300
Beilstein Reference
4-08-00-03277

Properties.
Formula
C15H10O4
Formula mass
254.24
Melting point, °C
196 - 197
Boiling point, °C
480
Vapor pressure, mmHg
3E-10 (25 C)
Density
0.92 g/cm3 (25C)
Solubility in water
Insoluble
pKa/pKb
6.34 (pKa)
Partition coefficient, pKow
4.26
Heat of vaporization
78.5 kJ/mol

Hazards and Protection.
Storage
Keep container closed when not in use. Store in a tightly closed container. Store in a cool, dry, well-ventilated area away from incompatible substances. Keep away from oxidizing agents.
Handling
Wash thoroughly after handling. Remove contaminated clothing and wash before reuse. Avoid contact with eyes, skin, and clothing. Keep container tightly closed. Avoid ingestion and inhalation. Use with adequate ventilation. Wash clothing before reuse.
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 prevent skin exposure.
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.
Small spills/leaks
Clean up spills immediately, using the appropriate protective equipment. Sweep up or absorb material, then place into a suitable clean, dry, closed container for disposal. Remove all sources of ignition. Provide ventilation.
Stability
Stable at room temperature in closed containers under normal storage and handling conditions.
Incompatibilities
Strong oxidizing agents.
Decomposition
Carbon monoxide, irritating and toxic fumes and gases, carbon dioxide.

Fire.
Flash Point,°C
264
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. Extinguishing media: Use agent most appropriate to extinguish fire. In case of fire use water spray, dry chemical, carbon dioxide, or appropriate foam.
Fire potential
This material is probably combustible.

Health.
Exposure effects
Effects may be delayed.
   Ingestion
May cause gastrointestinal irritation with nausea, vomiting and diarrhea.
   Inhalation
Causes respiratory tract irritation. Causes irritation of mucous membrane. Exposure may cause coughing, breathing difficulty, and possible pulmonary edema.
   Skin
Causes skin irritation.
   Eyes
Causes eye irritation. May cause chemical conjunctivitis.

First aid
 
   Ingestion
Never give anything by mouth to an unconscious person. Get medical aid immediately. 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
Immediately flush eyes with plenty of water for at least 15 minutes, occasionally lifting the upper and lower eyelids. Get medical aid immediately.

Transport.