2,3,4,4'-tetrakis(6-diazo-5,6-dihydro-5-oxo-1-naphthylsulfonato)benzophenone

Water solubility

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

July 15, 1992 to October 13, 1992

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method A.6 (Water Solubility)

Deviations:

no

GLP compliance:

no

Type of method:

column elution method

Key result

Water solubility:

< 10 mg/L

Conc. based on:

test mat.

Temp.:

20 °C

Details on results:

Preliminary experiments showed a water solubility of less than 10 mg/L.
As the substance is not stable in solutions under light exposure, the column elution method was performed under light exclusion, as far as possible.
As a result, the test substance does not elute with water. On the other hand the column check with acetonitrile showed a massive difference of 3 mg between applied and found test substance. Regarding poor stability in solution, both results have to be questioned. The water solubility was thus derived from the preliminary experiments.

Conclusions:

The water solubilty was determined to be <10 mg/L.

Executive summary:

The water solubility was determined using the column elution method, which was not easy to conduct as it is not possible under complete exclusion from light. Thus, the water solubilty was determined to be <10 mg/L based on preliminary results. 

Reference 2

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

October 24, 2019 to February 11,2020

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method A.6 (Water Solubility)

Deviations:

no

GLP compliance:

no

Type of method:

flask method

Specific details on test material used for the study:

Storage conditions: Refrigerator (2°C to 8°C)

Key result

Water solubility:

< 0.046 mg/L

Conc. based on:

test mat.

Temp.:

20 °C

Remarks on result:

other: solubility is below the quantification limit

Details on results:

Preliminary test
ln a stepwise procedure, increasing volumes of demineralized water were added at room temperature to a defined amount of the test item. After each addition of an amount of water the mixture was treated with ultrasound for 15 minutes and visually checked for any undissolved particles. Three additional preliminary tests were carried out with specified amounts of the test item and 100 mL and 500 mL demineralized water, respectively. After each addition of an amount of water, the mixture was stirred for at least 24 hours, and visually checked for any undissolved particles. None of the preliminary tests showed a completely solved test item. However, the solutions showed an intensive yellow colouration. The preliminary test showed that the water solubility of the test item was < 10 mg/L. According to the preliminary test the water solubility should have been determined by the column elution method in the main test. However, due to the colouration and the chemical characteristics of the test item value the flask method with two different loading rates was used.

Flask method (1st test series)
Two different loading rates were used (100 mg/L and 1000 mg/L). ln this test series normal glass equipment was used. The development of an analytical method was performed parallel to the flask method. During the development of the methodology it became apparent that the test item solutions were not stable under the influence of daylight. For this reason, this test series was not evaluated.

Flask method (2ndtest series)
Different from the 1st test series brown glass equipment was used to exclude an influence by light. Furthermore, two different loading rates were used (approx. 100 mg/L and 500 mg/L). After the equilibration time precipitate was observed in the flasks of the experiments excluding in the blank experiment.

ln the experiments with a loading rate of 100 mg/L and 500 mg/L the water solubility was below the detection limit of 0.046 mg/L.
The 1st test series was performed with clear glass equipment and the 2nd test series with brown glass equipment in order to protect the test item solutions from light. Furthermore, the standards for the calibration were diluted mixtures of acetonitrile and buffer solution (pH 4) in the 2nd test series. ln the 1st test series, the HPLC investigation of the test item dissolved in mixtures of acetonitrile and water showed several peaks. The HPLC chromatograms of the 2nd test series showed only one peak which could be assigned to the test item. Therefore, the HPLC measurements which were performed within the two test series indicated that the test item decomposes in the presence of light and depending of the pH value. According to the sponsor the intensive yellow colouration observed in the preliminary test is characteristic for the fine-grained test item. The colouration is presumably due to competing effects like slight amounts of very colour-intense impurities (referred to CoA) or dispersed particles in the test item solution or decomposition effects. Due to the instability of the test item it can only be assumed that the water solubility of the test item is below 10 mg/L.

Conclusions:

The water solubility cs of the test item at a temperature of 20°C was determined according to the flask method. It was found to be below the quantification limit: cs < 0.046 mg/L.

Executive summary:

The water solubility was determined according to OECD 105 using the flask method. The preliminary test showed that the water solubility of the test item is < 10 mg/L. The column elution method showed a solubility: cs < 0.046 mg/L.

Description of key information

The water solubility cs of the test item at a temperature of 20°C was determined according to the flask method and was found to be below the quantification limit, cs < 0.46 mg/L (reference 4.8-1).