Cobalt bis(2-ethylhexanoate)

Water solubility

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Qualifier:

according to guideline

Guideline:

other: OECD guideline for testing of chemicals - draft proposal - February 2001. Transformation dissolution of metals and metal compounds in aqueous media.

Qualifier:

according to guideline

Guideline:

other: The standard operating procedure for the transformation/dissolution of metals and sparingly soluble metal compounds, version February 2004.

GLP compliance:

no

Remarks:

The tests were following as close as possible the GLP guidelines proposed by OECD

Type of method:

flask method

Water solubility:

18 µg/L

Temp.:

21.8 °C

pH:

6.11

Remarks on result:

other: Co2Et concentration at 0 hour sampling time at 1 mg/L loading. Sample analysis was conducted in triplicate per test vessel (3 test vessels per loading). Average value from the tests is given.

Water solubility:

141.6 µg/L

Temp.:

21.5 °C

pH:

6.08

Remarks on result:

other: Co2Et concentration at 24 hour sampling time at 1 mg/L loading. Sample analysis was conducted in triplicate per test vessel (3 test vessels per loading). Average value from the tests is given.

Water solubility:

126.3 µg/L

Temp.:

21.4 °C

pH:

6.1

Remarks on result:

other: Co2Et concentration at 48 hour sampling time at 1 mg/L loading. Sample analysis was conducted in triplicate per test vessel (3 test vessels per loading). Average value from the tests is given.

Water solubility:

144.1 µg/L

Temp.:

21.3 °C

pH:

6.08

Remarks on result:

other: Co2Et concentration at 96 hour sampling time at 1 mg/L loading. Sample analysis was conducted in triplicate per test vessel (3 test vessels per loading). Average value from the tests is given.

Water solubility:

134.5 µg/L

Temp.:

21.3 °C

pH:

6.08

Remarks on result:

other: Co2Et concentration at 168 hour sampling time at 1 mg/L loading. Sample analysis was conducted in triplicate per test vessel (3 test vessels per loading). Average value from the tests is given.

Water solubility:

127.7 µg/L

Temp.:

21.9 °C

pH:

5.94

Remarks on result:

other: Co2Et concentration at 672 hour sampling time at 1 mg/L loading. Sample analysis was conducted in triplicate per test vessel (3 test vessels per loading). Average value from the tests is given.

Water solubility:

379 µg/L

Temp.:

22.4 °C

pH:

6.06

Remarks on result:

other: CoZEt concentration at 0 hour sampling time at 10 mg/L loading. Sample analysis was conducted in triplicate per test vessel (3 test vessels per loading). Average value from the tests is given.

Water solubility:

1 549.8 µg/L

Temp.:

21.1 °C

pH:

6.14

Remarks on result:

other: Co2Et concentration at 24 hour sampling time at 10 mg/L loading. Sample analysis was conducted in triplicate per test vessel (3 test vessels per loading). Average value from the tests is given.

Water solubility:

1 454.4 µg/L

Temp.:

21.3 °C

pH:

6.01

Remarks on result:

other: Co2Et concentration at 48 hour sampling time at 10 mg/L loading. Sample analysis was conducted in triplicate per test vessel (3 test vessels per loading). Average value from the tests is given.

Water solubility:

1 405.1 µg/L

Temp.:

21.8 °C

pH:

5.84

Remarks on result:

other: Co2Et concentration at 168 hour sampling time at 10 mg/L loading. Sample analysis was conducted in triplicate per test vessel (3 test vessels per loading). Average value from the tests is given.

Water solubility:

261.1 µg/L

Temp.:

21.7 °C

pH:

6.6

Remarks on result:

other: Co2Et concentration at 0 hour sampling time at 100 mg/L loading. Sample analysis was conducted in triplicate per test vessel (3 test vessels per loading). Average value from the tests is given.

Water solubility:

14 300.2 µg/L

Temp.:

21.9 °C

pH:

6.69

Remarks on result:

other: Co2Et concentration at 168 hour sampling time at 100 mg/L loading. Sample analysis was conducted in triplicate per test vessel (3 test vessels per loading). Average value from the tests is given.

Conclusions:

Under the conditions of the transformation/dissolution test, the dissolution of Co2Et is 127.7 µg/L at 1 mg/L loading for the 28-day endpoint. The dissolution of Co2Et is 1405.1 µg/L at 10 mg/L loading for the 7-day endpoint.The dissolution of Co2Et is 14300.2 µg/L at 100 mg/L loading for the 7-day endpoint.

Executive summary:

A seven day transformation/dissolution test according to the OECD guideline 29 and the GHS (Annex 10) protocol was run on Co2Et at a mass loading of 10 and 100 mg/L, at a pH of 6.0. Also a 28 day transformation/dissolution was run on Co2Et at a mass loading of 1 mg/L and at a pH of 6.0. Under the conditions of this test, the dissolution of Co2Et is 127.7 µg/L for the 28 -day endpoint (1 mg/L loading), 1405.1 µg/L for the 7-day endpoint (10 mg/L loading) and 14300.2 µg/L for the 7-day endpoint (100 mg/L loading).

Reference 2

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2008-09-14 to 2008-10-01

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:

no

GLP compliance:

no

Type of method:

flask method

Water solubility:

40.3 g/L

Temp.:

20 °C

pH:

6.8

Details on results:

The water solubility of the test material has been determined to be 40.3g/L of solution, at 20.0 +/- 0.5°C. however, the visual findings suggest that the solubility may be inversely proportional to temperature.

Conclusions:

Interpretation of results: very soluble (> 10000 mg/L).
The water solubility of the test material has been determined to be 40.3g/L of solution, at 20.0 +/- 0.5 °C. however, the visual findings suggest that the solubility may be inversely proportional to temperature.

Reference 3

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

2008-09-08 to 2008-12-10

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

no method validation was performed (ii) according to the results the test substance is depended on temperature, in this case it is necessary to perform the water solubility testing at 10°C as well

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

Version / remarks:

adopted 1995

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method A.6 (Water Solubility)

Version / remarks:

, 1992

Deviations:

no

GLP compliance:

no

Type of method:

flask method

Water solubility:

25 050 mg/L

Temp.:

20 °C

pH:

ca. 6.97

Water solubility:

6 300 mg/L

Temp.:

37 °C

pH:

>= 6.31 - <= 6.54

Details on results:

The water solubilities of cobalt 2-ethylhexanoate were determined to be 25.05 g/L at 20 °C (after 72 hours shaking) based on a measured concentration of 4.27 g Co/L (+/- 0.201 g Co/L) and 6.30 g/L at 37°C (after 72 hours shaking) based on a measured concentration of 1.07 g Co/L (+/- 0.201 g Co/L).

Conclusions:

Interpretation of results: very soluble (> 10000 mg/L).
The water solubilities of the test item cobalt 2-ethylhexanoate were determined to be 25.05 g/L at 20 °C based on a measured concentration of 4.27 g Co/L (+/- 0.201 g Co/L) and 6.30 g/L at 37°C based on a measured concentration of 1.07 g Co/L (+/- 0.201 g Co/L).

Description of key information

Water solubility of cobalt bis(2-ethylhexanoate) (flask method, guideline study results): 40.3 g/L at  20 °C.

Key value for chemical safety assessment

Water solubility:

40.3 g/L

at the temperature of:

20 °C

Additional information

Acc. to Walker et al. (2008) cobalt bis(2-ethylhexanoate) has a water solubility of 40.3 g/L at 20.0 °C. However, the visual findings suggest that the water solubility may be inversely proportional to temperature.

This observation is supported by a second experiment (Habeck, 2009), investigating the water solubility at 20 and 37°C. Hence, the water solubilities of cobalt bis(2-ethylhexanoate) were determined to be 25.05 g /L at 20 °C and 6.30 g/L at 37 °C.