Barium 4-dodecylphenolate

Water solubility

Link to relevant study record(s)

Reference

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2017-11-02 to 2017-12-06

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

Version / remarks:

1995

Deviations:

yes

Remarks:

Exclusion of CO2 and O2, two vessels was set up in a parallel design at 20 ± 1 °C, each vessel was sampled several times instead of sampling one vessel at every time point.

Qualifier:

according to guideline

Guideline:

EU Method A.6 (Water Solubility)

Version / remarks:

2008

Deviations:

yes

Remarks:

Exclusion of CO2 and O2, two vessels was set up in a parallel design at 20 ± 1 °C, each vessel was sampled several times instead of sampling one vessel at every time point.

GLP compliance:

yes

Type of method:

flask method

Specific details on test material used for the study:

Conditions of storage: Store at a dry place at room temperature (10 °C – 30 °C), in original container
Handling: Please handle the substance as far as possible under inert gas.

Water solubility:

7.172 g/L

Conc. based on:

element

Remarks:

barium

Loading of aqueous phase:

257.34 g/L

Incubation duration:

<= 16 d

Temp.:

20 °C

pH:

>= 12.9 - <= 13.1

Remarks on result:

other: loading based on test material barium 4-dodecylphenolate

Preliminary test

The preliminary test showed no equilibrium, the highest measurable water solubility of barium 4-dodecylphenolate was approximately 20 g / L at 20 °C after measuring the content of barium in the filtered solutions outside GLP. Based on the results of the pre-test and the measured pH it is assumed that the solubility of barium 4-dodecylphenolate corresponds to barium hydroxide (~ 40 g/L corresponding to 32 g Ba/L). Hence, the expected water solubility of barium 4-dodecyphenolate is in the range of 140 g/L. Using 5 times the expected solubility leads to an initial weight of barium 4-dodecylphenolate of ~ 700 g/L. Since, this loading is no more stirrable. Therefore, it was decided to use 250 g test substance/L for the main test.

 

	Test substance initial weight  [mg/L]	Ba dissolved [mg/L]		Content solved [%]	pH- Wert
1	400	17.3		19	9.30
2	904	53.6		27	10.70
3	2300	88.9		17	11.07
4	12842	539		19	11.95
5	99442	2183		10	12.52
6	247915	4430		8	12.82

 

Main test

The temperature of the water bath was 20 ± 1°C.

The pH of the test solutions were in the range between 12.9 and 13.1, the pH of the blanks were in the range between 6.9 and 7.1.

Measured dissolved barium concentrations of solutions containing the test item do not continuously increase during the test but vary from 6990 to 7440 mg barium / L. Measured dissolved barium concentrations of control solutions (i.e. background concentrations) are below the limit of quantification (LOQ).

Based on the barium content of barium 4-dodecylphenolate of 22.4 %, mean water solubility is estimated with 32.020 g barium 4-dodecylphenolate / L.

 

Calculated water solubility of barium in solution

 

 

Equilibration time (Days)	Measured concentration in mg barium / L
	Blank	1^st	2^nd	Mean (1^st& 2^nd)
8	< 0.93	7020	7140	7080
9	< 0.93	6990	7220	7105
14	< 0.93	7060	7340	7200
15	< 0.93	7040	7340	7190
16	< 0.93	7130	7440	7285
Mean	< 0.93	7048	7296	7172
Standard deviation	---	53	117	82
Relative standard deviation (%)	---	0.7	1.6	1.1

Conclusions:

Under the conditions of this test (under exclusion of CO2and O2, under inert gas; flask method; loadings of 255.21 g and 259.47 g test substance/L), a solubility equilibrium was reached during the first eight days of testing. The mean measured amount of dissolved barium on day 8, 9, 14, 15 and 16 at 20 ± 1 °C is 7172 mg/L (determined as dissolved barium, separated by filtration from undissolved test item). This would correspond to a water solubility of dissolved barium 4-dodecylphenolate of 32.02 g/L, calculated on a barium content of 22.4 %. However, this calculation may overestimate the solubility of 4-dodecylphenolate. Solution pH in samples containing the test item remained at 12.9 – 13.1 while the pH in method blanks ranged from 6.9 – 7.1.

Description of key information

The water solubility of barium 4-dodecylphenolate is 32.02 g/L at 20 ± 1 °C.

Key value for chemical safety assessment

Water solubility:

32.02 g/L

at the temperature of:

20 °C

Additional information

Under the conditions of this test (under exclusion of CO₂and O₂, under inert gas; flask method; loadings of 255.21 g and 259.47 g test substance/L), a solubility equilibrium was reached during the first eight days of testing. The mean measured amount of dissolved barium on day 8, 9, 14, 15 and 16 at 20 ± 1 °C is 7172 mg/L (determined as dissolved barium, separated by filtration from undissolved test item). This would correspond to a water solubility of dissolved barium 4-dodecylphenolate of 32.02 g/L, calculated on a barium content of 22.4 %. However, this calculation may overestimate the solubility of 4-dodecylphenolate. Solution pH in samples containing the test item remained at 12.9 – 13.1 while the pH in method blanks ranged from 6.9 – 7.1.