C.I. Reactive Yellow 2

Water solubility

Link to relevant study record(s)

Reference

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

17 November 2016 to 17 November 2016

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:

yes (incl. QA statement)

Type of method:

flask method

Key result

Water solubility:

> 377 g/L

Conc. based on:

test mat.

Loading of aqueous phase:

1.18 other: g/mL

Incubation duration:

30 min

Temp.:

20 °C

pH:

>= 6.97 - <= 7.05

Details on results:

CALIBRATION
Six concentration levels were used: 0.5, 1, 2, 5, 20 and 50 μg/mL. The calibration graph was calculated applying linear regression.

Summary of Standard Curve Parameters:
- Intercept: 0.398
- Slope: 42.2
- Correlation Coefficient: 1.0000

RESULTS OF THE SHAKE FLASK METHOD
The pH of the samples varied in the range of 6.97 – 7.05.
Based on the measured concentrations the test mixtures were homogeneous and the whole amount of the added test substance was dissolved. Measured concentrations are summarised in Table 1.
As the measured concentrations correspond to the total dissolution of the test substance, and also based on the justification measurement, water solubility of the test material is higher than 377 g/L at 20 °C.

Table 1. Results of the determination of the test item concentrations

Nominal Conc. mg/mL	pH	Calculated concentration mg/mL	Mean g/L
392	6.97	391	391
		390
394	7.03	392	394
		395
393	7.05	391	377
		364

Conclusions:

Under the conditions of the study, the water solubility of the test material is higher than 377 g/L at 20 °C.

Executive summary:

The water solubility of the test material was investigated in a GLP study conducted in accordance to the standardised guidelines OECD 105 and EU Method A.6.

As the expected water solubility is above 10^-2 g/L, the flask method was applied. About 10.0 g of test item was weighed into Erlenmeyer flasks. After addition of 20 mL water, the mixtures were stirred for 30 minutes. Three parallel solutions were made. Density of the test solutions was 1.18 g/mL (mean of three replicates). After the stirring flasks were removed the concentration in the clear solvent phase was determined by HPLC. The pH of each sample was recorded. The pH of the samples varied in the range of 6.97 – 7.05. Based on the measured concentrations the test mixtures were homogeneous and the whole amount of the added test substance was dissolved.

As the measured concentrations correspond to the total dissolution of the test substance, and also based on the justification measurement, the water solubility of the test material is higher than 377 g/L at 20 °C.

Description of key information

Under the conditions of the study, the water solubility of the test material is higher than 377 g/L at 20 °C.

Key value for chemical safety assessment

Water solubility:

377 g/L

at the temperature of:

20 °C

Additional information

The water solubilty of the test material was invesigated in a GLP study conducted in accordance to the standardised guidelines OECD 105 and EU Method A.6. The study was assigned a reliability score of 1 in accordance with the criteria for assessing data quality set forth by Klimisch et al. (1997).

As the expected water solubility is above 10^-2 g/L, the flask method was applied. About 10.0 g of test item was weighed into Erlenmeyer flasks. After addition of 20 mL water, the mixtures were stirred for 30 minutes. Three parallel solutions were made. Density of the test solutions was 1.18 g/mL (mean of three replicates). After the stirring flasks were removed the concentration in the clear solvent phase was determined by HPLC. The pH of each sample was recorded. The pH of the samples varied in the range of 6.97 – 7.05. Based on the measured concentrations the test mixtures were homogeneous and the whole amount of the added test substance was dissolved.

As the measured concentrations correspond to the total dissolution of the test substance, and also based on the justification measurement, the water solubility of the test material is higher than 377 g/L at 20 °C.