Trisodium bis[3-hydroxy-4-[(2-hydroxy-1-naphthyl)azo]naphthalene-1-sulphonato(3-)]chromate(3-)

Water solubility

Link to relevant study record(s)

Reference

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

February from 09 to 26, 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

test procedure in accordance with generally accepted scientific standards and described in sufficient detail

Reason / purpose for cross-reference:

reference to other study

Remarks:

validated analytical method

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

Version / remarks:

1995

GLP compliance:

yes (incl. QA statement)

Type of method:

flask method

Water solubility:

132.92 g/L

Conc. based on:

test mat.

Temp.:

20 °C

pH:

4.56 - 4.68

Details on results:

The recovery rate of the measured standard solutions was in the range from 98.6 to 105.9 %, which shows a good accuracy of the analytical method.

PRELIMINARY TEST
The preliminary test at room temperature indicated that the water solubility of the test item is between 7.6 and 28.7 g/l.

Flask	1a	2a	3a	4a
pH value	4.56	4.66	4.68	5.95
measured value [mg/l]	329.7 / 332.2	333.9 / 335.4	328.9 / 333.8	-- / --
aliquot of the flask [ml]	0.5	0.5	0.5	0.5
total volume after 1^stdilution [ml]	100	100	100	100
aliquot of the 1^stdilution [ml]	0.5	0.5	0.5	0.5
total volume after 2^nddilution [ml]	1	1	1	1
average water solubility [g/l]	132.38	133.84	132.53	--
mean value of the water solubility [g/l]	132.92			--
standard deviation [g/l]	0.81			--
relative standard deviation [%]	0.61			--

Conclusions:

132.92 g/l at ca 20 °C and pH 4.56 – 4.68

Executive summary:

The water solubility of the test item was determined according to the OECD guideline 105. The preliminary test at room temperature indicated that the water solubility of the test item is between 7.6 and 28.7 g/l. The solubility of the test item in water at room temperature was estimated to be clearly bigger than 0.01 g/l. Therefore, the flask method was performed.

For the main test three flasks were prepared with an amount of test item and water, and one flask only with water. After stirring and centrifugation the aqueous phases were measured by means of HPLC. The solution of each flask has been measured twice at ca 20 °C. To verify the accuracy of the analytical method a fresh prepared standard solution (prepared with the test item) was measured in between the samples of the flask method.

In the main test, the recovery rate of the measured standard solutions was in the range from 98.6 to 105.9 %, which shows a good accuracy of the analytical method.

The water solubility at ca 20 °C and pH 4.56 – 4.68 of the test item was determined to be 132.92 g/l RSD = 0.61 %

Conclusion

132.92 g/l at ca 20 °C and pH 4.56 – 4.68

Description of key information

132.92 g/l at ca 20 °C and pH 4.56 – 4.68

Key value for chemical safety assessment

Water solubility:

132.92 g/L

at the temperature of:

20 °C

Additional information

OECD 105 - flask method