Reaction products of tetrazotized 5-amino-2-[(E)-2-(4-amino-2-sulfophenyl)ethenyl]benzenesulfonic acid with 6-amino-4-hydroxynaphthalene-2-sulfonic acid and 4-amino-5-hydroxynaphthalene-2,7-disulfonic acid in 2-[bis(2-hydroxyethyl)amino]ethanol

Hydrolysis

Administrative data

Endpoint:

hydrolysis

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Report date:

2018

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 111 (Hydrolysis as a Function of pH)

Version / remarks:

2004

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

[Reaction mass of 2,7-Naphthalenedisulfonic acid, 5-amino-3-[[4-[2-[4-[(7-amino-1-hydroxy-3-sulfo-2-naphthalenyl)azo]-2-sulfophenyl]ethenyl]-3-sulfophenyl]azo]-4-hydroxy-, compd. with 2,2',2''-nitrilotris[ethanol] (1:5) and 3,3'-[ethylenebis[(3-sulpho-p-phenylene)azo]]bis[5-amino-4-hydroxynaphthalene-2,7-disulphonic] acid, compound with 2,2',2''-nitrilotriethanol (1:6) and 3,3'-[vinylenebis[(3-sulpho-p-phenylene)azo]]bis[6-amino-4-hydroxynaphthalene-2-sulphonic] acid, compound with 2,2',2''-nitrilotriethanol (1:4)]

EC Number:

916-899-6

Molecular formula:

not available

IUPAC Name:

[Reaction mass of 2,7-Naphthalenedisulfonic acid, 5-amino-3-[[4-[2-[4-[(7-amino-1-hydroxy-3-sulfo-2-naphthalenyl)azo]-2-sulfophenyl]ethenyl]-3-sulfophenyl]azo]-4-hydroxy-, compd. with 2,2',2''-nitrilotris[ethanol] (1:5) and 3,3'-[ethylenebis[(3-sulpho-p-phenylene)azo]]bis[5-amino-4-hydroxynaphthalene-2,7-disulphonic] acid, compound with 2,2',2''-nitrilotriethanol (1:6) and 3,3'-[vinylenebis[(3-sulpho-p-phenylene)azo]]bis[6-amino-4-hydroxynaphthalene-2-sulphonic] acid, compound with 2,2',2''-nitrilotriethanol (1:4)]

Test material form:

liquid

Radiolabelling:

no

Study design

Analytical monitoring:

yes

Buffers:

Citrate Buffer (0.05 M): pH 4
Phosphate Buffer (0.05 M): pH 7
Borate Buffer (0.05 M): pH 9

Details on test conditions:

TEST SYSTEM
- Type, material and volume of test flasks, other equipment used: glass volumetric flasks
- Sterilisation method: filtration through pre-assembled sterile 500 mL filters (Nalgene).
- Lighting: performed under dark conditions
- Measures taken to avoid photolytic effects: dark conditions
- Measures to exclude oxygen: each sterilized buffer solution was purged in a gentle stream of nitrogen for approx. 20 min to deplete any dissolved oxygen.
- open system
- No indication of the test material adsorbing to the walls of the test apparatus

TEST MEDIUM
- Volume used/treatment 10 mL
- Kind and purity of water: Millipore
- Mobile phase: Solvent A: 0.05 M Ammonium acetate in Millipore water, Solvent B:Acetonitrile

OTHER TEST CONDITIONS
- Adjustment of pH: buffers used

Number of replicates:

3 replicates at each pH level

Positive controls:

no

Negative controls:

yes

Remarks:

Blanks were tested

Results and discussion

Preliminary study:

The average recoveries obtained in Tier 1 testing were always in the range of 90-110 %. All main components of the substance were hydrolyzed less than the 10 %. This indicated a sufficient hydrolytic stability of three components of the test item different buffer solutions after 5 days of incubation at 50 °C.

Transformation products:

not measured

Total recovery of test substance (in %)

Total recovery of test substance (in %) 1

% Recovery:

> 93.4 - < 103

St. dev.:

9.3

pH:

4

Temp.:

50 °C

Duration:

5 d

Total recovery of test substance (in %) 2

% Recovery:

> 93.9 - < 99.9

St. dev.:

10.1

pH:

7

Temp.:

50 °C

Duration:

5 d

Total recovery of test substance (in %) 3

% Recovery:

> 95.9 - < 97.1

St. dev.:

8.9

pH:

9

Temp.:

50 °C

Duration:

5 d

Dissipation DT50 of parent compound

Key result

Remarks on result:

hydrolytically stable based on preliminary test

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The substance is hydrolytically stable.

Executive summary:

No significant hydrolysis (≤ 10 %) was observed in the preliminary test at 50 °C for all tested pH values (4, 7, 9) of the test item. This indicates a half-life period of analytes at 25 °C of more than 1 year (t_{0.5 25°C} > 1 year). Thus, the test item was considered to be hydrolytically stable and a further testing (Tier 2 experiments) (according to OECD guideline 111) is not required.