N1,N3-diallylpropane-1,3-diamine dihydrochloride

Water solubility

Link to relevant study record(s)

Reference

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2020-05-25 to 2020-06-25

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

Qualifier:

according to guideline

Guideline:

EU Method A.6 (Water Solubility)

Qualifier:

according to guideline

Guideline:

EPA OPPTS 830.7840 (Water Solubility)

GLP compliance:

no

Type of method:

flask method

Key result

Water solubility:

> 497 g/L

Conc. based on:

test mat. (dissolved fraction)

Temp.:

20 °C

pH:

4.2

Remarks on result:

other: Mean solubility resulting from two experiments

Preliminary estimation of the water solubility - visual estimation:

Increasing amounts of distilled water were added stepwise to 94.11 mg of the test item and the mixture was shaken for 10 minutes (Table 1).

Table 1: Appearance of test mixtures - I

Amount of test item [mg]	Total volume [mL]	Appearance of mixture
94.11	0.1	Undissolved particles
	0.5	Clear solution, test item completely dissolved

In a total volume of 0.5 mL of distilled water the test item was completely dissolved. Thus, the water solubility of the test item in distilled water was estimated to be between 188.22 g/L and 941.1 g/L. Due to the fact that the estimated solubility of the test item was above 10 mg/L, the main test for the determination of the water solubility had to be performed according to the flask method.

Visual estimation with adapted weights and quantities of distilled water:

Due to the wide solubility range, the pre-test was carried out with adapted weights and quantities of distilled water in order to obtain a more accurate result. Increasing amounts of distilled water were added step-wise to 977.19 mg of the test item. The test item was weighed into a 10 mL graduated cylinder, then increasing volumes of distilled water were added portion-wise at room temperature according to Table 2. After each addition up to the indicated amount of distilled water, the mixture was shaken vigorously for 10 minutes and visually checked for any undissolved amounts of the sample.

Table 2: Appearance of the test mixtures - II

Amount of test item [mg]	Total volume [mL]	Appearance of mixture	Final volume [mL]
977.19	0.5	Undissolved particles
	0.6	Undissolved particles
	0.7	Undissolved particles
	0.8	Undissolved particles
	0.9	Undissolved particles
	1.0	Clear solution, test item completely dissolved	1.9

After addition of 1.0 mL distilled water, the test item was completely dissolved. The final volume increased to 1.9 mL. This results in a water solubility in distilled water of about 514 g/L.

Main test (flask method):

The amounts given in Table 3 are initial weights of the test item. 1 mL of distilled water were added to three individual sample weights of approximately 2.5 g of the test item and stirred at 30 °C for different time intervals. After equilibration (24 h at 20 °C), the samples were partly gel-like, partly solid and a separation was not possible. Therefore, the test was stopped and a minimum solubility was determined.

Table 3: Test conditions for the experiments in distilled water

Flask	1	2	3	Blank
Amount test item [mg]	2504.32	2501.29	2503.31	-
Stirring time at 30 °C [h]	72	48	24	72
Equilibration time at 20 °C [h]	24	24	24	24

Minimum solubility:

Two sample weights of approximately 1000 mg of the test item were weighed into 2 mL volumetric flasks. The flasks were filled with distilled water and stirred at 20 °C for 2 hours. After equilibration aliquots of the clear aqueous phases were diluted 0.1 mL to 100 mL with water / acetonitrile (95:5, v/v) and 0.4 mL to 100 mL water / acetonitrile (95:5, v/v). The aliquots were directly analysed by HPLC. Each sample was injected twice.

Table 4: Test conditions of the minimum solubility in distilled water

Test	1	2	Blank
Amount test item [mg]	995.04	1001.52	-
Stirring time at 30 °C [h]	-	-	-
Equilibration time at 20 °C [h]	2.0	2.0	2.0
pH at room temperature	4.29	4.16	6.23

Mean concentration test 1: 490.4 g/L (490.8090 and 490.0683 g/L), mean concentration test 2: 497.2 g/L (495.6553 and 498.7960 g/L), minimum solubility (test 1 and 2) 497 g/L (relative standard deviation: 1%)

The measured concentrations of test no. 1 and test no. 2 were found to be concentrations of clear solutions of the test item in distilled water. As there was no undissolved test item left, the measured concentrations can be regarded as minimum solubilities at the analysed pH. The actual solubility of the test item in distilled water might be higher than the measured minimum solubility.

Conclusions:

The water solubility of the test item at 20 °C was determined to be > 497 g/L (pH 4.2).

Executive summary:

The water solubility of the test item was determined according to OECD guideline 105 by the flask method applying HPLC. The water solubility of the test item at 20 °C was determined to be > 497 g/L (pH 4.2).

Description of key information

The water solubility of the test item was determined according to OECD guideline 105 by the flask method applying HPLC. The water solubility of the test item at 20 °C was determined to be > 497 g/L (pH 4.2).

Key value for chemical safety assessment

Water solubility:

497 g/L

at the temperature of:

20 °C