Sodium 2,4-diamino-5-(4-(2-sulfoxyethanesulfonyl)phenylazo)benzenesulfonate

Additional toxicological data

Administrative data

Endpoint:

additional toxicological information

Type of information:

other: Expert Statement

Adequacy of study:

supporting study

Study period:

18 May 2006

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: The expert statement report compares the relevant toxicity between the free acid and salt forms with regards to biological and toxicological significance and read across terms. The full comparative report is appended below.

Materials and methods

Type of study / information:

Expert Review of the Comparison Between Reactive Yellow 201 and Everzol Yellow GSP Related to Potential Biological Effects.

Test guideline

Qualifier:

no guideline required

Principles of method if other than guideline:

The paper comprises of an Expert Review of the Comparison Between Reactive Yellow 201 and Everzol Yellow GSP Related to Potential Biological Effects.

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

-

EC Number:

461-870-9

EC Name:

-

Cas Number:

795275-80-8

Molecular formula:

C14H14N4Na2O9S3

IUPAC Name:

Sodium 2,4-diamino-5-(4-(2-sulfoxyethanesulfonyl)phenylazo)b enzenesulfonate

Details on test material:

Not applicable.

Results and discussion

Any other information on results incl. tables

From the information presented it is clear that in any biological system (and hence for the safety evaluation of human or environmental hazard assessment) there will be no difference between the qualitative effects of Reactive Yellow 201 and Everzol Yellow GSP. However, if a risk assessment is being performed based on the exposure to the test item on a weight basis (e.g. mg/kg bodyweight) then there is a small difference between the two materials.

In biological terms, the activity of each material will be identical on a molar basis, but the molecular weight of Reactive Yellow 201 is 522.49 (assuming the di-sodium salt) and the molecular weight of Everzol Yellow GSP is 478.52. So for all toxicology experiments performed on Everzol Yellow GSP, any numeric values such as NOAEL or LC50, to calculate the equivalent value for Reactive Yellow 201, the numeric value should be multiplied by (522.49/478.52) which is all cases will make only a small difference, the heavier molecule being slightly "safer" than Everzol Yellow GSP on a numeric scale. There would in practice be little or no real difference between the two molecules under most experimental situations.

 

In the production of both Everzol Yellow GSP and Reactive Yellow 201, the method of synthesis is identical up to the point of final isolation. The pH of the solution at isolation will affect which salt is produced, the dry pure product will either possess the Na or the H group on the charged oxygen. As described in the report, as soon as the material is dissolved again, the equilibrium will be reached almost instantly and at an acid pH the ionised form will be

predominant.

 

In summary, all biological effects would be the result of dissolved material, and when in an aqueous solution, there is no difference between the biological activities of Everzol Yellow GSP and Reactive Yellow 201 on a molar basis.

Applicant's summary and conclusion

Conclusions:

There is no toxicological or biological significance between Reactive Yellow 201 and Everzol Yellow GSP.

Executive summary:

In summary, all biological effects would be the result of dissolved material, and when in an aqueous solution, there is no difference between the biological activities of Everzol Yellow GSP and Reactive Yellow 201 on a molar basis.