Disodium 5-amino-4-hydroxy-3-(phenylazo)naphthalene-2,7-disulphonate

Endpoint summary

Additional information

Appearance/physical state/colour:

The substance, disodium-5-amino-4-hydroxy-3-(phenylazo)naphthalene-2,7-disulphonate, is an organic solid present as Dark reddish brown powder.

Melting point/freezing point:

The melting point determination of disodium-5-amino-4-hydroxy-3-(phenylazo)naphthalene-2,7-disulphonate (CAS No. 3567-66-6) was done following OECD Guideline 102 and according to the metal block capillary method. The test was conducted in replicates and mean decomposition point was inferred to be greater than 350 °C at 976.4hPa.

Boiling point:

From Danish QSAR the boiling point of test substance disodium 5-amino-4-hydroxy-3-(phenylazo)naphthalene-2,7-disulphonate was estimated to be 717.34°C. This value has been considered for the purpose of chemical safety assessment.

Density:

The density of test itemdisodium-5-amino-4-hydroxy-3-(phenylazo)naphthalene-2,7-disulphonate(CAS No. 3567-66-6) was determined following OECD guideline 109 and according to themethod recommended in the International Pharmacopoeia, fourth Edition, 2014. The mean pour and tapped  density of the test item was found to be0.4000 g/cm³and 0.4880 g/cm³at 32.8^oC and 967.3hPa

Particle size distribution (Granulometry):

The particle size distribution of test itemdisodium-5-amino-4-hydroxy-3-(phenylazo) naphthalene-2,7-disulphonate(CAS No. 3567-66-6 ) was determined by granulometric analysis with rotap sieve shaker. The particle size distribution was found to be in the range of 150 micron to 10 micron. The majority of the particles were found to range between 75 to 150 micrometer (microns) indicating that the particles are not of inhalable size

Vapour pressure:

Vapour pressure of test substance D&C Red No 33 was found to be 1.002584E-21 Pa at 25 °C.

Partition coefficient:

Partition coefficient of test substance D&C Red No 33 was found to be log Kow -2.09.This log Kow value indicate that test substance is hydrophilic in nature.

Water solubility:

The water solubility determination of test itemdisodium-5-amino-4-hydroxy-3-(phenylazo) naphthalene-2,7-disulphonate (CAS No. 3567-66-6 ) was done as per the shake flask method. The water solubility value was found to be 54.45 g/L at 26 °C. Thus, it can be concluded that the test chemical is very soluble in water.

Surface tension:

In accordance with column 2 of Annex VII of the REACH regulation, this testing needs to be carried out only if surface activity is a desired property of the chemical. The chemical disodium 5-amino-4-hydroxy-3-(phenylazo)naphthalene-2,7-disulphonate (Common name: D&C Red 33) is used mostly as a home products and personal care color. For these uses, surface activity is not a desired property and hence this end point was considered for waiver.

Flash point:

The flash point determination of Test itemdisodium-5-amino-4-hydroxy-3-(phenylazo)naphthalene-2,7-disulphonate(CAS No. 3567-66-6) was done. The method is closed cup method using Pensky-Martens Flash Point Apparatus. The mean flashpoint of the test item was found to be greater than 250°C at 970.5 hPa. For the purpose of chemical safety assessment, the flash point has been considered to be 251oC

Auto flammability:

The chemical disodium 5-amino-4-hydroxy-3-(phenylazo)naphthalene-2,7-disulphonate (Common name: D&C Red 33) does not catch fire spontaneously upon exposure to air under normal conditions of temperature and pressure. Thus, the chemical is unlikely to be "Auto Flammable". Thus, this end point was considered for waiver.

Flammability:

The NFPA rating for flammability is not applicable to the chemical disodium 5-amino-4-hydroxy-3-(phenylazo)naphthalene-2,7-disulphonate (Common name: D&C Red 33). Also, there are no evidences that indicates that this chemical is flammable. Thus, this end point was considered for waiver. For the purpose of chemical safety assessment, the chemical is considered to be "Non Flammable".

Explosiveness:

In accordance with column 2 of Annex VII of the REACH regulation, the study is scientifically unjustified since there are no chemical groups associated with explosive properties present in the molecule of the chemical disodium 5-amino-4-hydroxy-3-(phenylazo)naphthalene-2,7-disulphonate (Common Name: D&C Red 33); except the azo group. Also, there are no known evidence that the chemical is explosive. Thus, this end point was considered for waiver. For the purpose of chemical safety assessment, the chemical is considered as "Non Explosive".

Oxidising properties:

In accordance with column 2 of Annex VII of the REACH regulation, the substance disodium 5-amino-4-hydroxy-3-(phenylazo)naphthalene-2,7-disulphonate (Common Name: D&C Red 33) is incapable of reacting exothermically with combustible materials,on the basis of the chemical structure. It is an organic substance containing oxygen atoms but no halogen atoms but these elements are not chemically bonded to nitrogen or oxygen. THus, the chemical is unlikely to exhibit oxidising properties and this study was therefore considered for waiver. The chemical is not considered to be Oxidising for the purpose of chemical safety assessment.

pH

The pH determination of test item disodium-5-amino-4-hydroxy-3-(phenylazo)naphthalene-2,7-disulphonate (CAS No.3567-66-6) was done as per the test guideline OECD 122. The pH of the test solution was determined with the help of digitalpH meter. The pH was found to be 6.60 at 28.3 °C.