Fatty acids, C9-13-neo-, copper 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:

2018-01-16 to 2018-02-23

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:

Two vessels will be set up in a parallel design, each vessel will be 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:

Two vessels will be set up in a parallel design, each vessel will be 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:

signed 2016-05-31

Type of method:

flask method

Specific details on test material used for the study:

Storage conditions: Room temperature tightly closed

Key result

Water solubility:

158 mg/L

Conc. based on:

test mat. (dissolved fraction)

Loading of aqueous phase:

350 mg/L

Incubation duration:

>= 36 - <= 37 d

Temp.:

20 °C

pH:

>= 6.1 - <= 6.2

Remarks on result:

other: SD: ± 41.0 mg/L

Remarks:

based on a purity of 97 %

Water solubility:

24.9 mg/L

Conc. based on:

element (dissolved fraction)

Remarks:

Cu

Loading of aqueous phase:

350 other: mg test item /L

Incubation duration:

>= 36 - <= 37 d

Temp.:

20 °C

pH:

>= 6.1 - <= 6.2

Remarks on result:

other: SD: ± 6.5 mg/L

Details on results:

- Mean temperature: was 19.9 ± 0.7 °C (necessary range 20.0 ± 1.0 °C)
- pH value of solutions containing the test item: from 5.8-6.1 (day 1) to 6.1-6.2 (day 37)
- pH value in method blanks: from 7.3–7.5 at (day 1) to 6.5–6.6 (day 37)
- turbidity in samples from test was always <1 NTU indicating that filtered solutions did not contain any undissolved material

Recovery / validation data for copper

Element Cu	Recovery [%]	SD [%]	n (total)	n (valid)
TMDA-70.2 nominal value Cu: 407 μg/L	109	0.6	4	4
	107	0.3	4	4
TMDA-70.2 (dilution factor 2) nominal value Cu: 407 μg/L diluted 203.5 μg/L	102	0.8	4	4
	102	1.1	3	3
	104	1.7	3	3
Quality control standard (Roth) 7.5 μg/L	103	5.3	4	4
	102	6.6	5	4
Quality control standard (Roth) 75 μg/L	104	1.5	4	4
	104	0.4	5	4
	105	1.7	4	4
	104	0.3	3	3
	106	0.9	3	3
Quality control standard (Roth) 750 μg/L	105	0.8	4	4
	103	0.6	4	4
	105	1.3	4	4
	104	0.5	3	3
	104	0.5	3	3
Recalibration standard 100 μg/L	97.5	1.5	4	4
	99.3	1.1	4	4
Recalibration standard 400 μg/L	101	1.1	4	4
	99.7	0.2	3	3
	101	0.6	3	3

 

Fortification of test samples with copper

Sample	element	measured concentration [μg/L]	calculated level after addition [μg/L]	recovery [μg/L] / [%]
Vessel 1 sample a 1d 1 mL sample + 4 mL 100 μg/L standard	Cu	64.5	92.9	90.7 / 97.7
Vessel 1 sample a 13d 1 mL sample + 4 mL 250 μg/L standard	Cu	479	296	297 / 100
Vessel 2 sample a 28d 1 mL sample + 4 mL 75 μg/L standard	Cu	381	136	137 / 101
Vessel 2 sample a 37d 1 mL sample + 4 mL 75 μg/L standard	Cu	419	144	142 / 98.8

Mean copper concentrations of vessel 1 and 2 over the whole sampling time.

Sampling [d]	sample	LOD [μg/L]	LOQ [μg/L]	Cu conc. per vessel ± SD [mg/L]	mean Cu conc. all vessels ± SD [mg/L]	Variation / change between samplings [%]
1	Vessel 1	1.17	3.52	3.20 ± 0.03	2.49 ± 1.01	-
	Vessel 2	1.17	3.52	1.78 ± 0.03
2	Vessel 1	1.17	3.52	5.46 ± 0.05	4.15 ± 1.85	66.7
	Vessel 2	1.17	3.52	2.85 ± 0.11
3	Vessel 1	1.17	3.52	7.79 ± 0.10	5.79 ± 2.83	39.6
	Vessel 2	1.17	3.52	3.79 ± 0.12
13	Vessel 1	4.14	12.4	23.2 ± 1.01	15.7 ± 10.7	171
	Vessel 2	4.14	12.4	8.15 ± 0.16
14	Vessel 1	4.14	12.4	24.6 ± 0.09	16.8 ± 11.1	6.75
	Vessel 2	4.14	12.4	8.93 ± <0.01
28	Vessel 1	0.924	2.77	28.4 ± 0.10	23.7 ± 6.76	41.2
	Vessel 2	0.924	2.77	18.9 ± 0.26
29	Vessel 1	0.924	2.77	28.9 ± 0.32	24.3 ± 6.52	2.58
	Vessel 2	0.924	2.77	19.7 ± 0.11
36	Vessel 1	1.61	4.82	29.2 ± 0.19	24.4 ± 6.74	0.49
	Vessel 2	1.61	4.82	19.6 ± 0.07
37	Vessel 1	1.61	4.82	29.8 ± 0.09	25.4 ± 6.19	4.13
	Vessel 2	1.61	4.82	21.0 ± 0.11

The determination of the water solubility of fatty acids, C9-13-neo, copper salts is based on mean copper concentrations of the two last sampling days (36, 37 d) and a mean copper amount of 15.3% in the test item. The amount of dissolved Fatty acids, C9-13-neo, copper salts was calculated, with a test item purity of ≥90 %; ≥ 97 % (boundary composition of the registered substance) and 100 % (w/w) as follows:

Mean copper concentrations

Vessel 1: 29.5 ± 0.38 mg Cu/L

Vessel 2: 20.3 ± 0.81 mg Cu/L

Mean: 24.9 ± 6.5 mg Cu/L

If based on a test item purity of ≥ 90 % the water solubility of fatty acids, C9-13-neo, copper salts is Mean of concentration x 90 % / 15.3 %:

Vessel 1: 173 ± 2.2 mg/L

Vessel 2: 120 ± 4.7 mg/L

Mean: 146 ± 38.0 mg/L

If based on a test item purity of ≥ 97 % the water solubility of fatty acids, C9-13-neo, copper salts is Mean of concentration x 97 % / 15.3 %:

Vessel 1: 187 ± 2.4 mg/L

Vessel 2: 129 ± 5.1 mg/L

Mean: 158 ± 41.0 mg/L

If based on a test item purity of 100% the water solubility of fatty acids, C9-13-neo, copper salts is Mean of concentration x 100 % / 15.3 %:

Vessel 1: 193 ± 2.5 mg/L

Vessel 2: 133 ± 5.3 mg/L

Mean: 163 ± 42.3 mg/L

Conclusions:

Under the conditions of this test (under exclusion of CO2 and O2, under inert gas; flask method; loadings of 350.14 mg and 350.06 mg test substance/L in vessel 1 and 2, respectively), a solubility equilibrium was reached at day 36, 37 of testing. The mean measured amount of dissolved copper on day 36 and 37 at 20 ± 1 °C is 24.9 ± 6.5 mg/L (determined as dissolved copper, separated by filtration from undissolved test item). This corresponds to a water solubility of dissolved fatty acids, C9-13-neo, copper salts of 158 ± 41.0 mg/L, calculated on a copper content of 15.3 % and a test substance purity of 97 % (w/w). Solution pH in samples containing the test item remained at 6.1 – 6.2 while the pH in method blanks ranged from 6.5 – 7.5.

Description of key information

Fatty acids, C9-13-neo, copper salts has a water solubility of 158 ± 41.0 mg/L, calculated on a copper content of 15.3 % and a test substance purity of 97 % (w/w) at

20 ± 1 °

Key value for chemical safety assessment

Water solubility:

158 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 350.14 mg and 350.06 mg test substance/L in vessel 1 and 2, respectively), a solubility equilibrium was reached at day 36, 37 of testing. The mean measured amount of dissolved copper on day 36 and 37 at 20 ± 1 °C is 24.9 ± 6.5 mg/L (determined as dissolved copper, separated by filtration from undissolved test item). This corresponds to a water solubility of dissolved fatty acids, C9-13-neo, copper salts of 158 ± 41.0 mg/L, calculated on a copper content of 15.3 % and a test substance purity of 97 % (w/w). Solution pH in samples containing the test item remained at 6.1 – 6.2 while the pH in method blanks ranged from 6.5 – 7.5.