Phenol, 4-(9H-carbazol-3-ylamino)-, reaction products with sodium sulfide (Na2(Sx)) and sulfur, leuco deriv.

Water solubility

Link to relevant study record(s)

Reference

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

22 August - 26 September, 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

Version / remarks:

July 27, 1995

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method A.6 (Water Solubility)

Version / remarks:

19 March 2014

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPPTS 830.7840 (Water Solubility)

Version / remarks:

March 1998

Deviations:

no

Principles of method if other than guideline:

The solubility of the test item is below 0.01 g/L, so the column elution method should be applied according to the guideline. However, column elution method is not feasible with this test item, because coating of the support material is not possible due to the low solubility of the test item in any solvent. Therefore, the flask method was applied.

GLP compliance:

yes (incl. QA statement)

Type of method:

flask method

Remarks:

shake flask method

Specific details on test material used for the study:

Expiry date: September 12, 2021

Water solubility:

>= 1.69 - <= 1.73 mg/L

Conc. based on:

act. ingr. (dissolved fraction)

Loading of aqueous phase:

5 000 mg/L

Incubation duration:

24 h

Temp.:

20 °C

pH:

>= 4.16 - <= 4.19

Remarks on result:

other: Mean with the 95% confidence intervals 1.71 ± 0.02 mg/L

Water solubility:

>= 1.34 - <= 1.96 mg/L

Conc. based on:

act. ingr. (dissolved fraction)

Loading of aqueous phase:

5 000 mg/L

Incubation duration:

48 h

Temp.:

20 °C

pH:

4.18

Remarks on result:

other: Mean with the 95% confidence intervals 1.65 ± 0.31mg/L.

Water solubility:

>= 1.6 - <= 1.778 mg/L

Conc. based on:

act. ingr. (dissolved fraction)

Loading of aqueous phase:

5 000 mg/L

Incubation duration:

72 h

Temp.:

20 °C

pH:

>= 4.17 - <= 4.22

Remarks on result:

other: Mean with the 95% confidence intervals 1.69 ± 0.09 mg/L

Key result

Water solubility:

1.68 mg/L

Conc. based on:

act. ingr.

Loading of aqueous phase:

5 000 mg/L

Incubation duration:

>= 24 - <= 72 h

Temp.:

20 °C

pH:

4.2

Details on results:

Results of the test and measured concentrations of test item are presented in the following table. The measured concentrations are constant within ± 15 % and thus within the range required by the guidelines

Results of the Method Validation

Measurement repeatability (7 parallels)	CV% ≤ 0.5 %
Repeatability of the Preparation (n=5)	CV%< 2 %
Linear range	0.2 - 20 µg/mL
Correlation coefficients	> 0.999
Limit of Quantification	0.2 µg/mL
Limit of Detection	0.1 µg/mL
Recovery from ISO medium	101 %
Recovery from20X AAPmedium	≥ 99 %
Recovery from ultra-pure water	102 %
Accuracy(samples used for calibration)	≤6 %
Precision	≤ 6 % (9 % at LOQ)
Stability of the test item in ISO medium at the temperature 18-22 °C for 2 days	46 % at the test conditions
Stability of the test item in 20X AAP medium at the temperature 22-26 °C for 7 days	<LOD
Stock solution stability (1 mg/ml), after dissolution, dye complexation and color development	stable for at least 7 days at 5±3 °C

Results of the determination of test item concentrations

Sampling time	Measured concentration of test item (mg/L )		Measured pH
	Test vessels	Mean withthe 95% confidence intervals
After 24h	1.72	1.71 ± 0.02	4.17
	1.70		4.16
	1.71		4.19
After 48h	1.51	1.65 ± 0.31	4.18
	1.69		4.18
	1.76		4.18

Results of the determination of test item concentrations (continued)

Sampling time	Measured concentration of test item (mg/L )				Measured pH
	Test vessels		Mean withthe 95% confidence intervals
After 72h	1.65		1.69 ± 0.09		4.18
	1.72				4.22
	1.71				4.17
Solubility ofthe test item (mg/L)	1.68 ± 0.07	-
RSD%	2	-
Ultra-pure water			< LOQ	5.96-5.98

Conclusions:

In conclusion the water solubility of the test item was determined to be 1.68 ± 0.07 mg/L (95% confidence interval) at 20 °C ± 1 °C using the shake-flask method for the performance.

Executive summary:

The water solubility of the test item was assessed according to OECD Guideline 105, EU Method A.6 and US EPA OPPTS 830.7840 under GLP conditions. The solubility of the test item is below 10 ^-2g/L, so the column elution method should be applied according to the guideline. However, column elution method is not feasible with this test item, because coating of the support material is not possible due to the low solubility of the test item in any solvent. Therefore, the shake-flask method was applied. In result, the water solubility of the test item was determined to be 1.68 +/- 0.07 (95% confidence interval) at 20 °C +/- 1 °C.

Description of key information

The water solubility of the substance was determined to be 1.68 ± 0.07 mg/L (95% confidence interval)  at 20 °C ± 1 °C using the shake-flask method for the performance.

Key value for chemical safety assessment

Water solubility:

1.68 mg/L

at the temperature of:

20 °C

Additional information

The water solubility of the test item was assessed according to OECD Guideline 105, EU Method A.6 and US EPA OPPTS 830.7840 under GLP conditions. The shake-flask method was applied. The water solubility of the test item was determined to be 1.68 ± 0.07 (95% confidence interval) at 20 °C ± 1 °C