Fatty acids, C6-19-branched, calcium salts

Water solubility

Link to relevant study record(s)

Reference

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2019-01-18 to 2019-02-18

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:

Three vessels were set up in a parallel design, each vessel was sampled several times instead of sampling one vessel at every point in time/ exclusion of O2 and CO2, under inert gas (argon)

Qualifier:

according to guideline

Guideline:

EU Method A.6 (Water Solubility)

Version / remarks:

2008

Deviations:

yes

Remarks:

Three vessels were set up in a parallel design, each vessel was sampled several times instead of sampling one vessel at every point in time/ exclusion of O2 and CO2, under inert gas (argon)

GLP compliance:

yes (incl. QA statement)

Remarks:

2016-05-31

Type of method:

flask method

Specific details on test material used for the study:

Appearance: yellow brown highly viscous sticky solid
Storage conditions: Keep in a well-ventilated place. Containers which are opened must be carefully resealed and kept upright to prevent leakage. Observe label precautions. Do not store in heat or direct sunlight.

Key result

Water solubility:

323 mg/L

Conc. based on:

test mat. (dissolved fraction)

Loading of aqueous phase:

1 g/L

Incubation duration:

>= 23 - <= 24 d

Temp.:

20 °C

pH:

>= 8.51 - <= 8.96

Remarks on result:

other: S.D: ± 59 mg/L

Remarks:

Calculated on a mean dissolved calcium concentration of 21.9 ± 4.0 mg/L and a calcium content of 6.8 %.

Water solubility:

21.9 mg/L

Conc. based on:

element

Remarks:

Ca

Loading of aqueous phase:

1 other: g test item /L

Incubation duration:

>= 23 - <= 24 d

Temp.:

20 °C

pH:

>= 8.51 - <= 8.96

Remarks on result:

other: S.D: ± 4.0 mg/L

Details on results:

- Observations: During the test the substance adhered to the sample boat and after 22 days a slight layer (probably organic parts) was observed on the surface of the test solutions. Sample boats were transferred inside the test vessels prior to start. For the method blank vessels, blank sample boats were added to the ultrapure water.
- Mean temperatur: 20.3 ± 0.1 °C and 20.1 ± 0.1 °C
- Oxygen: Almost no oxygen was detectable (– 0.2 – 2.3 %)
- Turbidity: < 1 NTU indicating that filtered solutions did not contain any undissolved material
- Subtraction of method blanks is not needed because the calcium concentrations in method blanks (< 0.021 mg/L) were far below concentrations in actual samples (6.5 mg/L - 26.9 mg/L).
- The variation of the mean dissolved calcium concentration of sampling days 23, 24 is less than 15 % and an increasing trend was not observed, therefore the requirements of the OECD 105 were fulfilled.

ICP-OES measurement (series on January 24, 2019) with corresponding LOD/LOQ, correlation coefficient and sum of quality assurance samples and recovery.

Calibration [µg/L] – lowest and highest calibration point	Chosen wavelength [nm]	LOD [µg/L]	LOQ [µg/L]	Correlation coefficient	Sum of quality assurance samples	Recovery of quality assurance samples [%]
January 24, 2019; measurement of samples and method blanks (days 1, 2, 3). Samples a, b from vessel 5 after 3 days are above calibration range. Repeated at February 01, 2019.
2.5 – 1000 (total of 13 calibration points, 12 used + blank)	396.847	0.078	0.233	0.99997	27	92.6
February 01, 2019; measurement of samples and method blanks (days 8, 9, 10). Repeated measurement of samples a, b from vessel 5 after 3 days.
2.5 – 1000 (total of 13 calibration points, 12 used + blank)	422.673	0.317	0.952	0.99999	19	94.7
February 18, 2019; measurement of samples and method blanks (days 22, 23, 24).
2.5 – 1000 (total of 13 calibration points, 12 used + blank)	183.944	1.30	3.90	0.99993	19	100

Recovery/validation data copper of measurement series

Element Ca	Recovery [%]	SD [%]	n (total)	n (valid)
January 24, 2019
Recalibration standard 25 µg/L	103	7	6^#	5^#
Quality control standard (Roth) 50 µg/L	98.3	0.9	6^$	5^$
Recalibration standard 250 µg/L	97.0	0.5	6	5
Quality control standard (Roth) 500 µg/L	98.8	0.9	6	6
February 01, 2019
Quality control standard (Roth) 75 µg/L	100	1	4	4
LGC6019 (dilution factor 1000), nominal value Cu: 109 mg/L – diluted 109 µg/L	106²	1²	4²	3²
Recalibration standard 250 µg/L	98.2	0.7	4	4
Quality control standard (Roth) 750 µg/L	96.9	0.3	4	4
February 18, 2019
Quality control standard (Roth) 75 µg/L	98.9	1.3	4	4
LGC6019 (dilution factor 1000), nominal value Cu: 109 mg/L – diluted 109 µg/L	104	1	4	4
Recalibration standard 250 µg/L	98.5	0.7	4	4
Quality control standard (Roth) 750 µg/L	99.3	0.4	4	4

^#    Recovery of one sample is at 118 % and therefore not within the limits of 100 ± 15 %. This is not critical because 92.6 % of all QA/QC samples are within these limits.

^$    Recovery of one sample is at 1549 % and therefore not within the limits of 100 ± 15 %. A reason for this is not known, might be a contamination. Therefore, this recovery is not included in calculation. This is not critical because 92.6 % of all QA/QC samples are within these limits.

²    Probable contamination of one sample because Ca concentration is above detector maximum. Therefore, this sample is excluded from calculation of recovery.

 

Selected samples were fortified with known amounts of calcium (by standard addition of commercial standard) to determine the standard recoveries of this element.

Fortification of measurement series

Sample	Element	Measured concentration [µg/L]	Calculated level after addition [µg/L]	Recovery [µg/L] / [%]
January 24, 2019
Vessel 3 sample a 1d (19Y0175, dilution 10-fold) – 1 mL sample 4 mL 500 µg/L standard	Ca	718	544	536/98.7
Vessel 5 sample a 2d (19Y0195, dilution 10-fold) – 1 mL sample 4 mL 750 µg/L standard	Ca	974	795	778/97.9
Vessel 3 sample a 3d (dilution 10-fold) – 1 mL sample 4 mL 1000 µg/L standard	Ca	931	986	975/98.9
February 01, 2019
Vessel 3 sample a 8d (19Y0227, dilution 20-fold) – 1 mL sample 4 mL 750 µg/L standard	Ca	605	721	722/100
Vessel 4 sample a 9d (19Y0239, dilution 20-fold) – 1 mL sample 4 mL 1000 µg/L standard	Ca	461	892	891/99.8
Vessel 5 sample a 10d (19Y0251, dilution 20-fold) – 1 mL sample 4 mL 750 µg/L standard	Ca	693	739	746/101
February 18, 2019
Vessel 3 sample a 22d (19Y0471, dilution 20-fold) –1 mL sample 4 mL 750 µg/L standard	Ca	227	645	661/102
Vessel 4 sample a 23d (19Y0483, dilution 20-fold) – 1 mL sample 4 mL 500 µg/L standard	Ca	189	438	441/101
Vessel 5 sample a 24d (19Y0495, dilution 20-fold) – 1 mL sample 4 mL 1000 µg/L standard	Ca	218	844	858/102

The determination of the water solubility of Fatty acids, C6-19-branched, calcium saltsis based on mean dissolved Ca concentrations of sampling days (23, 24 d) and a calcium amount of 6.8 % in the test item

Calculation of water solubility according to calcium (6.8 %). (3, 4, 5 – triplicate vessels; a, b – duplicate samples).

	Ca conc. [mg/L]	Mean Ca conc. [mg/L]	SD [mg/L]	mean Ca all samples [mg/L]	SD [mg/L]	Ca in test item [%]	Calculated amount of test item dissolved on Basis of Ca (6.8 %) [mg/L]	Mean dissolved test item [mg/L]	SD [mg/L]	mean all samples [mg/L]	SD [mg/L]
3a d23	26.3	26.5	0.5	21.9	4.0	6.8	386	389	7	323	59
3b d23	26.8						394
3a d24	25.9						381
3b d24	26.9						395
4a d23	18.9	17.4	2.1				279	256	30
4b d23	19.3						283
4a d24	16.7						245
4b d24	14.9						218
5a d23	22.1	21.9	0.2				326	322	2
5b d23	21.8						321
5a d24	21.8						320
5b d24	21.9						323

Mean Ca concentrations:

Vessel 3:        26.5 ± 0.5 mg/L

Vessel 4:        21.9 ± 2.0 mg/L

Vessel 5:        19.5 ± 0.1 mg/L

Mean:             21.9 ± 4.0 mg/L

Water solubility of Fatty acids, C6-19-branched, calcium salts is calculated: Mean of concentration x 100 % / 6.8 %:

Vessel 3:        389.3 ± 6.9 mg/L

Vessel 4:        322.1 ± 30 mg/L

Vessel 5:        287.1 ± 2.1 mg/L

Mean:             322.7 ± 58.9 mg/ L

Conclusions:

Under the conditions of this test (under exclusion of CO2 and O2, under inert gas; flask method; loadings of 1020, 987.8 and 1079 mg/L test substance in triplicate vessels, a solubility equilibrium was observed during testing. No increasing trend in calcium concentrations after 22 days was observed. The mean measured amount of dissolved calcium at 20.0 ± 1.0 °C is 21.9 ± 4.0 mg/L (determined as dissolved calcium on days 23 and 24 separated by filtration from undissolved test item). This corresponds to a test item water solubility of 323 ± 59 mg/L, calculated on a calcium content of 6.8 %.
The pH of test solutions remained within 8.3 and 9.2. The pH of method blanks ranged between 5.4 – 7.6.

Description of key information

Fatty acids, C6-19-branched, calcium salts has a water solubility of 323 ± 59 mg/L at 20 °C.

Key value for chemical safety assessment

Water solubility:

323 mg/L

at the temperature of:

20 °C

Additional information

Under the conditions of this test (under exclusion of CO2 and O2, under inert gas; flask method; loadings of ~1 g/L test substance in triplicate vessels), a solubility equilibrium was observed during testing. No increasing trend in calcium concentrations after 22 days was observed. The mean measured amount of dissolved calcium at 20.0 ± 1.0 °C is 21.9 ± 4.0 mg/L (determined as dissolved calcium on days 23 and 24 separated by filtration from undissolved test item). This corresponds to a test item water solubility of 323 ± 59 mg/L, calculated on a calcium content of 6.8 %.