Sodium pyruvate

Partition coefficient

Link to relevant study record(s)

Reference

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Study period:

from 2018-05-03 to 2018-05-30

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 107 (Partition Coefficient (n-octanol / water), Shake Flask Method)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method A.8 (Partition Coefficient - Shake Flask Method)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPPTS 830.7550 (Partition Coefficient, n-octanol / H2O, Shake Flask Method)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

flask method

Partition coefficient type:

octanol-water

Analytical method:

high-performance liquid chromatography

Key result

Type:

log Pow

Partition coefficient:

-3.83

Temp.:

20 °C

pH:

>= 6.88 - <= 7.63

Type:

Pow

Partition coefficient:

0

Temp.:

20 °C

pH:

>= 6.88 - <= 7.63

Table - Measured concentrations

Ratio of solvents (n-Octanol : Water)	Measured concentration in n-octanol phase (µg/mL)		Measured concentration in aqueous phase (µg/mL)		pH
10:1	0.23		1498.8		7.41
	0.28		1587.1		7.29
	0.27		1603.6		7.24
Mean	0.26		1563.1		7.31
RSD %	10		4		-
Measured quantity of test item (Mo; Mw)	11.8 µg		7112 µg		-
Total nominal quantity of test item (Ms)	7217 µg
Total quantity of test item (Mo + Mw)	7124 µg
Recovery	99 %
Ratio of solvents (n-Octanol : Water)	Measured concentration in n-octanol phase (µg/mL)		Measured concentration in aqueous phase (µg/mL)		pH
20:1	0.38		2892.0		7.12
	0.35		2963.4		7.17
	0.39		2971.5		7.22
Mean	0.37		2942.3		7.17
RSD%	6		1		-
Measured quantity of test item (Mo; Mw)	17.7 µg		7061 µg		-
Total nominal quantity of test item (Ms)	7217 µg
Total quantity of test item (Mo + Mw)	7079 µg
Recovery	98 %
5:1	0.15	906.3		7.63
	0.16	916.8		7.34
	0.11	924.9		6.88
Mean	0.14	916.0		7.28
RSD%	19	1		-
Measured quantity of test item (Mo; Mw)	5.8 µg	7648 µg		-
Total nominal quantity of test item (Ms)	7217 µg
Total quantity of test item (Mo + Mw)	7654 µg
Recovery	106 %

Table - Calculated partition coefficient (Pow) and log Pow

Ratio of solvents (n-Octanol : Water)	Partition coefficient	Log Partition coefficient
	Pow	Log Pow
10:1	0.0002	-3.78
20:1	0.0001	-3.90
5:1	0.0002	-3.82
Mean all	0.0001	-3.83

 

Conclusions:

The partition coefficient (Pow) of the test item in an n-octanol / water two-phase system was determined to be 0.0001 using shake flask method. The logPow was determined to be -3.83 ± 0.055 (95 % confidence interval).

Executive summary:

A study was conducted in accordance with OECD TG 107, Regulation (EC) No 440/2008 method A.8 and OPPTS 830.7550 to determine the partition coefficient of the test item using the shake flask method. A stock solution of known concentration (~ 0.8 g/L) of the test substance in n-octanol, pre-saturated with water, was prepared. The samples were extracted with ultrapure water in 1:1 volume ratio. The phases were separated by centrifugation (4000 rpm, 5 min, 20 °C) and the aqueous phase was diluted with ultrapure water for HPLC analysis. The samples of n-octanol phases were concentrated with ultrapure water, then directly measured by HPLC. The samples of water phases were diluted with ultrapure water before the HPLC analysis. Test vessels with octanol/water mixture in three different ratios were shaken for 5 minutes by hand. Separation of the two phases was achieved by centrifugation at 20 °C (5 min, 4000 rpm). Then the two phases were analysed using HPLC. The partition coefficient (Pow) of the test item in an n-octanol / water two-phase system was determined to be 0.0001 using shake flask method. The logPow was determined to be -3.83 ± 0.055 (95 % confidence interval).

Description of key information

The partition coefficient (Pow) of the test item in an n-octanol / water two-phase system was determined to be 0.0001 using shake flask method. The logPow was determined to be -3.83 ± 0.055 (95 % confidence interval).

Key value for chemical safety assessment

Log Kow (Log Pow):

-3.83

at the temperature of:

20 °C

Additional information

A study was conducted in accordance with OECD TG 107, Regulation (EC) No 440/2008 method A.8 and OPPTS 830.7550 to determine the partition coefficient of the test item using the shake flask method. A stock solution of known concentration (~ 0.8 g/L) of the test substance in n-octanol, pre-saturated with water, was prepared. The samples were extracted with ultrapure water in 1:1 volume ratio. The phases were separated by centrifugation (4000 rpm, 5 min, 20 °C) and the aqueous phase was diluted with ultrapure water for HPLC analysis. The samples of n-octanol phases were concentrated with ultrapure water, then directly measured by HPLC. The samples of water phases were diluted with ultrapure water before the HPLC analysis. Test vessels with octanol/water mixture in three different ratios were shaken for 5 minutes by hand. Separation of the two phases was achieved by centrifugation at 20 °C (5 min, 4000 rpm). Then the two phases were analysed using HPLC. The partition coefficient (Pow) of the test item in an n-octanol / water two-phase system was determined to be 0.0001 using shake flask method. The logPow was determined to be -3.83 ± 0.055 (95 % confidence interval).