Sodium glyoxylate

Partition coefficient

Administrative data

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Experimental starting date: 28 March 2017 Experimental completion date: 22 June 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2017

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

flask method

Partition coefficient type:

octanol-water

Test material

Test material information

Constituent 1

Reference substance name:

Sodium glyoxylate

EC Number:

220-298-8

EC Name:

Sodium glyoxylate

Cas Number:

2706-75-4

Molecular formula:

C2H2O3.Na

IUPAC Name:

sodium oxoacetate

Specific details on test material used for the study:

Identification: Safelink SPM-01
Appearance/Physical state: colorless to slightly yellow powder
Batch: G150201
Purity: 99.9%
Expiry date: not supplied
Storage conditions: room temperature, in the dark

Study design

Analytical method:

photometric method

Results and discussion

Partition coefficient

Key result

Type:

log Pow

Partition coefficient:

2.2

Temp.:

22 °C

pH:

6.8

Details on results:

Preliminary Estimate
The log10 Pow was calculated to be: -5.21

Discussion
The determination of partition coefficient was performed using the shake-flask method. This
was due to the expected partition coefficient obtained in the preliminary assessment.
The stock solution was prepared in n-octanol saturated water in place of water saturated
n-octanol. This was due to the insolubility of the test item in the organic phase. This issue
has been considered to have had a negligible impact on the overall result and has been
considered to be more appropriate to obtain a realistic partition coefficient value.
As there was no definitive test item detected in the organic phases, a limit valve for the
sample concentrations was taken based on the organic phase sample with the highest
absorbance. This result was corrected for the absorbance of the organic phase matrix blank
extract. This approach provided a worst case scenario and resulted in the final result being a
limit value. Although the test item was a complex mixture, it is considered that the test result
represents the test item as a whole.

Validation
The linearity of the detector response with respect to concentration was assessed over the
nominal concentration ranges of 5 to 50 mg/L (organic phases) and 50 to 500 mg/L (aqueous
phases). The results were satisfactory with a correlation coefficient (r) of 0.998 and 0.999
being obtained respectively.

Any other information on results incl. tables

Results

The partition coefficient determined for each flask is shown in the following table:

Flask	Organic/ Aqueous Volume Ratio	Partition Coefficient	Log10 Pow	Mean Partition Coefficient
1	02:01	≤6.00 x 10^3	≤2.22	≤2.22
2		≤5.98 x 10^3	≤2.22
3	04:01	≤5.82 x 10^3	≤2.24	≤2.22
4		≤6.08 x 10^3	≤2.22
5	08:01	≤6.02 x 10^3	≤2.22	≤2.22
6		≤6.30 x 10^3	≤2.22

Overall Pow : ≤6.30 x 10^-3

Overall log₁₀ P_ow : ≤2.20

Applicant's summary and conclusion

Conclusions:

The partition coefficient of the test item has been determined to be less than or equal to be
6.30 x 10-3 at 22.0 ± 0.5 °C, log10 Pow of ≤2.20.

Executive summary:

Less than or equal to be 6.30 x 10^-3 at 22.0 ± 0.5 °C,

log₁₀ P_ow of ≤2.20, using the shake-flask method, designed to be compatible with Method A.8

Partition Coefficient of Commission Regulation (EC) No 440/2008 of 30 May 2008 and

Method 107 of the OECD Guidelines for Testing of Chemicals, 13 April 2004.