Molecular Formula: C₃₀H₁₅FeN₃Na₃O₁₅S₃
Molar mass: 878.46 g/mol
EINECS: 243-010-2
Water solubility: 30 mg/mL
Appearance: Dark green to black powder
Product categories: Organometallics;Transition Metal Compounds;Classes of Metal Compounds
Structure of Naphthol Green B (19381-50-1):
 
XLogP3-AA: 2.9
H-Bond Donor: 0
H-Bond Acceptor: 18
IUPAC Name: Trisodium; iron(3+); 5-oxidoimino-6-oxonaphthalene-2-sulfonate
Canonical SMILES: C1=CC2=C(C=CC(=O)C2=N[O-])C=C1S(=O)(=O)[O-].C1=CC2=C(C=CC(=O)C2=N[O-])C=
C1S(=O)(=O)[O-].C1=CC2=C(C=CC(=O)C2=N[O-])C=C1S(=O)(=O)[O-].[Na+].[Na+].
[Na+].[Fe+3]
InChI: InChI=1S/3C10H7NO5S.Fe.3Na/c3*12-9-4-1-6-5-7(17(14,
15)16)2-3-8(6)10(9)11-13;;;;/h3*1-5,13H,(H,14,15,16);;;;/q;;;+3;3*+1/p-6 
InChIKey: ZHHKVLCBIBQGKO-UHFFFAOYSA-H

 Naphthol Green B (19381-50-1) is a green nitroso dye and is used in histology to stain collagen and for polychrome stains with animal tissue. For industry purposes Naphthol, it is used for staining wool, nylon, paper, anoxidized aluminium and soap.

Carcinogenicity ofNaphthol Green B (19381-50-1) hasn't been listed as a carcinogen by NTP, IARC,ACGIH, or CA Prop 65.You can see actual entry in RTECS for complete information.

Reported in EPA TSCA Inventory.

Moderately toxic by intravenous route. When heated to decomposition it emits very toxic fumes of SO_x and NO_x.
 

Safety Statements:
22:  Do not breathe dust
24:  Avoid contact with skin
25:  Avoid contact with eyes

 Naphthol Green B (19381-50-1) also can be called Trisodium tris[5,6-dihydro-5-(hydroxyimino)-6-oxo-2-naphthalenesulfonato(2-)-N5,O6]-ferrate(III) ; Acid green 1 .It is hazardous,so the first aid measures and others should be known.Such as: When on the skin: should  flush skin with plenty of water immediatelyfor at least 15 minutes while removing contaminated clothing.Or in the eyes: Flush eyes with plenty of water for at least 15 minutes, occasionally lifting the upper and lower eyelids.While ,it's Inhaled: Remove from exposure and move to fresh air immediately.Then you have the ingesting of the product : Do not induce vomiting.If conscious and alert, rinse mouth and drink 2-4 cupfuls of milk or water.
In addition, Naphthol Green B (19381-50-1) can be stable under normal temperature and pressure conditions.You must not take it with strong oxidants.And also prevent it to broken down into hazardous decomposition products: irritating and toxic fumes and gases, oxides of sulfur, oxides of nitrogen, carbon dioxide, carbon monoxide.