Registration Dossier

Data platform availability banner - registered substances factsheets

Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Physical & Chemical properties

Endpoint summary

Administrative data

Description of key information

Additional information


On the basis of physical observation , Disodium 2-(3-oxo-6-oxidoxanthen-9-yl)benzoate was found to be a solid dark red crystalline powder.

Melting Point:

The melting point determination of Disodium 2-(3-oxo-6-oxidoxanthen-9-yl)benzoate (CAS No. 518-47-8 )was done following OECD Guideline 102 and according to the metal block capillary method. The test was conducted in replicates and mean melting temperature range was found to be 313.3°C -317°C° at 966.7 hPa

Boiling Point:

According to Column II of Annex VII, the boiling point study does not need to be conducted for solids which either melt above 300 °C or decompose before boiling.

The substance 4-Amino-5-hydroxynaphthalene-1,7-disulphonic acid is a solid at room temperature and it is reported to melt at temperature range of of 313.3- 317 °C .Hence, it is not feasible to determine boiling point and the endpoint was considered for waiver.


The mean pourdensity and tapped densityof test itemDisodium 2-(3-oxo-6-oxidoxanthen-9-yl)benzoate (CAS No. 518-47-8)was determined following OECD Guideline 109 and according to theaccording to themethod recommended in the International Pharmacopoeia, fourth Edition, 2014 using bulk density apparatus.The mean pour density and tapped density of the test item was found to be0.5793 g/cm3and 0.7794 g/cm3at 29.6oC and 966.7 hPa.

Particle Size Distribution:

The particle size distribution of test item Disodium 2-(3-oxo-6-oxidoxanthen-9-yl)benzoate (CAS No. 518-47-8)was determined by granulometric analysis with rotap sieve shaker. The particle size distribution was found to be in the range of 150 micron to 53 micron.

Vapour Pressure:

The estimated vapor pressure of the test chemical at 25°C is 1.6x10-17 mm Hg.

Partition coefficient:

YASUHIRO OBA and SIMON R. POULSON(2012) measured the values of logKow vs. pH for fluorescein and eosin Y, two of the most commonly used fluorescent dye tracers.

Fluorescein (sodium salt, CAS: 518-47-8) was obtained from Sigma-Aldrich. The value of the octanol-water partition coefficient (Kow) was determined by the shake-flask method. The log Pow value for fluorescein sodium at pH = 7.0 was determined to be 0.34.

Water Solubility:

The test compound Fluorescein sodium is very much soluble in water with solubility value of 4.0X10+4 mg/L.

Surface Tension:

In accordance with column 2 of Annex VII of the REACH regulation, the study need only be conducted if surface activity is a desired property of the chemical. The chemical Disodium 2-(3-oxo-6-oxidoxanthen-9-yl)benzoate (Common Name: Fluorescein sodium) is widely used as a fluorescent tracer for many medical applications, where surface activity is not an important consideration. Hence this study was considered for waiver.

Flash point:

The flash point determination of Disodium 2-(3-oxo-6-oxidoxanthen-9-yl) benzoate (CAS No. 518-47-8)was done following closed cup method using Pensky-Martens flash point apparatus. The test was conducted in replicates and mean flash point was found to be 217.6 °C at 967.3 hPa


disodium 3-oxo-3H-spiro[2-benzofuran-1,9'-xanthene]-3',6'-diolate did not catch fire on being exposed to air at room temperature of 27°C and atmospheric pressure of 966 hPa. This indicates that disodium 3-oxo-3H-spiro[2-benzofuran-1,9'-xanthene]-3',6'-diolate is not auto-flammable


The chemical Disodium 2-(3-oxo-6-oxidoxanthen-9-yl)benzoate (Common Name: Fluorescein sodium) does not catch fire upon exposure to air at normal conditions of temperature and pressure. Thus the chemical is not likly to be "Auto flammable" and hence this end point was considered for waiver.


In accordance with column 2 of Annex VII of the REACH regulation, the study does not need to be conducted since there are no chemical groups associated with explosive properties present in the molecule of Disodium 2-(3-oxo-6-oxidoxanthen-9-yl)benzoate (Common Name: Fluorescein sodium). Thus, the chemical is likely to be "Non explosive".

Oxidising Properties:

In accordance with column 2 of Annex VII of the REACH regulation, the substance Disodium 2-(3-oxo-6-oxidoxanthen-9-yl)benzoate (Common Name: Fluorescein sodium) is incapable of reacting exothermically with combustible materials on the basis of the chemical structure. It is an organic substance containing oxygen but no halogen atoms and these elements are not chemically bonded to nitrogen or oxygen. Thus, the chemcial is likely to be "Non-oxidising".


The pH determination of test itemDisodium 2-(3-oxo-6-oxidoxanthen-9-yl) benzoate (CAS No. 518-47-8) wasdone following OECD guideline 122. The pH of 1% w/v aqueoussolutionwas measured with the help of pH meter and the mean pH was observed to be 8.36 at 32°C


In accordance with Section 2 of REACH Annex XI, information requirement section 7.17, this study cannot be conducted on solid materials or gases. According to ECHA Chapter 7 guidance, viscosity measurement is only relevant to liquids.The test chemical Disodium 6-hydroxy 3- oxo 9-xanthene-o-benzoate is a solid . Hence this endpoint was considered for waiver.