Sodium (S)-lactate

Partition coefficient

Link to relevant study record(s)

Reference

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2013-05-27 to 2013-12-10

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)

Version / remarks:

adopted 27th July 1995

Deviations:

no

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

GLP compliance:

yes

Type of method:

flask method

Partition coefficient type:

octanol-water

Specific details on test material used for the study:

- Name of test material (as cited in study report): PURASAL S
- Chemical name: Sodium-L-lactate
- Appearance: light yellow liquid
- Analytical purity: 59.8% (12.3% Na)
- Lot/batch No.: 1208001453
- Expiry date: 13 August 2014
- Storage condition: at room temperature

Analytical method:

high-performance liquid chromatography

other: ICP-AES

Key result

Type:

log Pow

Partition coefficient:

< -1.52

Temp.:

20 °C

pH:

7

Remarks on result:

other: based on sodium (mean)

Type:

log Pow

Partition coefficient:

< -2.13

Temp.:

20 °C

pH:

7

Remarks on result:

other: based on lactate (mean)

Type:

log Pow

Partition coefficient:

-4.77

Remarks on result:

other: calculated result (QSAR)

Details on results:

see box "Any other information on results incl. tables".

Table 1: Sodium analysis - sample compositions & results

Sample No	Volume of		Initial amount of	Actual amount after equilibrium in		Recovery in both phases
	Buffer (ml)	n-octanol (ml)	Sodium (mg)	Buffer (mg)	n-octanol (mg)	In % of used amount
1A	10	10	2.12	2.15	<0.068	101.3
1B	10	10	2.32	2.32	<0.068	100.3
2A	10	20	2.12	2.14	<0.136	101.1
2B	10	20	2.32	2.33	<0.136	100.5
3A	20	10	4.24	4.25	<0.068	100.3
3B	20	10	4.64	4.61	<0.068	99.6

 

Table 2: Sodium analysis - concentrations in the phases and partition coefficients

Sample No	Actual concentration of Na in		Pow	log Pow	pH of the aqueous phase in equilibrium
	n-octanol (mg/l)	Buffer (mg/l)
1A	<6.8	215	<0.032	<-1.50	7
1B	<6.8	232	<0.029	<-1.54	6.9
2A	<6.8	214	<0.032	<-1.50	7
2B	<6.8	233	<0.029	<-1.53	7
3A	<6.8	213	<0.032	<-1.50	7
3B	<6.8	231	<0.029	<-1.53	7

Table 3: Lactate analysis - sample compositions & results

Sample No	Volume of		Initial amount of	Actual amount after equilibrium in		Recovery in both phases
	Buffer (ml)	n-octanol (ml)	Lactate (mg)	Buffer (mg)	n-octanol (mg)	In % of used amount
1A	10	10	8.21	12.86	<0.1	157.9
1B	10	10	8.97	14.00	<0.1	157.2
2A	10	20	8.21	12.86	<0.1	159.1
2B	10	20	8.97	13.98	<0.1	158.1
3A	20	10	16.42	25.74	<0.2	157.4
3B	20	10	17.94	28.00	<0.2	156.6

Table 4: Lactate analysis - concentrations in the phases and partition coefficients

Sample No	Actual concentration of lactate in		Pow	log Pow	pH of the aqueous phase in equilibrium
	n-octanol (mg/l)	Buffer (mg/l)
1A	<10	1286	<0.0078	<-2.11	7
1B	<10	1400	<0.0071	<-2.15	6.9
2A	<10	1286	<0.0078	<-2.11	7
2B	<10	1398	<0.0072	<-2.15	7
3A	<10	1287	<0.0078	<-2.11	7
3B	<10	1400	<0.0071	<-2.15	7

The log Pow of <-1.52 of sodium was taken as most appropriate to represent the log Pow of Sodium (S)-lactate.

Conclusions:

The log Pow of Sodium (S)-lactate is < –1.52.

Executive summary:

In a GLP study conducted according to OECD 107, the shake flask method was applied to determine the octanol/water partition coefficient of Sodium (S)-lactate. The test substance is a salt - therefore the partition coefficient of the test item was determined from cations and anions, i.e., the analysis of the sodium content and the lactate content in both liquid phases.
Based on sodium, the partition coefficient was determined as log Pow < -1.52 (key value).
Based on lactate, the partition coefficient was determined as log Pow < -2.13.

Description of key information

In a GLP study conducted according to OECD 107, the shake flask method was applied to determine the octanol/water partition coefficient of Sodium (S)-lactate.

The log Pow was determined to be < -1.52 at 20 °C.

Key value for chemical safety assessment

Log Kow (Log Pow):

-1.52

at the temperature of:

20 °C