Methyl α-D-mannopyranoside

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 2021-01-13 to 2021-01-25

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:

1995

Deviations:

no

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

2008

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

estimation method (solubility ratio)

Partition coefficient type:

octanol-water

Key result

Type:

log Pow

Partition coefficient:

>= -3.2 - <= -2.9

Temp.:

20 °C

pH:

ca. 6.5

First preliminary test for the estimation of the 1-octanol solubility:

Amount of test item / g	Total volume of added octanol / mL	Stirring time at RT / h:min	Remark
0.3	11	3:10	Not dissolved
	41	0:45	Not dissolved
	91	16:10	Not dissolved
	141	96:00	Not dissolved

According to the first preliminary test the solubility of the test item in 1-octanol was estimated to be < 2.13 g/L.

 

Second preliminary test for the estimation of the 1-octanol solubility:

Total amount of test item / g	Added volume of octanol / mL	Stirring time at RT / h:min	Remark
11.2	50	45:00	Dissolved
21.9		120:00	Not dissolved

According to the second preliminary test the solubility of the test item in 1-octanol was estimated to be between 0.2 and 0.4 g/L.

With these values of the estimated 1-octanol solubility and the estimated water solubility in the range of 324.3 and 329.3 g/L, the partition coefficient (log Pow) of the test item can be estimated to be between -3.2 and -2.9

Conclusions:

The log Pow of the test item was estimated to be between -3.2 and -2.9.

Executive summary:

An experimental study was conducted according to OECD Guideline 107 and Regulation (EC) No. 440/2008, Method A.8 using the estimation method based on the solubilities of the test item in water and 1-octanol, respectively. The water solubility was estimated to be in the range of 324.3 and 329.3 g/L. The 1-octanol solubility of the test item was estimated to be between 0.2 and 0.4 g/L. Therefore, the partition coefficient (log Pow) of the test item was estimated to be between -3.2 and -2.9.

Description of key information

The log Pow of the test item was estimated to be between -3.2 and -2.9 (reference 4.7-2).

Key value for chemical safety assessment

Log Kow (Log Pow):

-2.9

at the temperature of:

20 °C

Additional information

Key study

An experimental study was conducted according to OECD Guideline 107 and Regulation (EC) No. 440/2008, Method A.8 using the estimation method based on the solubilities of the test item in water and 1-octanol, respectively. The water solubility was estimated to be in the range of 324.3 and 329.3 g/L. The 1-octanol solubility of the test item was estimated to be between 0.2 and 0.4 g/L. Therefore, the partition coefficient (log Pow) of the test item was estimated to be between -3.2 and -2.9.

 

Supporting study

Additionally, the logPow was calculated using KOWWIN v1.68 as part of EPISuite v4.11 from US Environmental Protection Agency.

Using KOWWIN v1.68 the log Kow of the test item was calculated to be -2.5039 at 25 °C (EPI Suite, 2014). The substance is within the applicability domain of the model. Thus the estimation is accurate (reference 4.7-1).

The adequacy of a prediction depends on the following conditions:

a) the (Q)SAR model is scientifically valid: the scientific validity is established according to the OECD principles for (Q)SAR validation;

b) the (Q)SAR model is applicable to the query chemical: a (Q)SAR is applicable if the query chemical falls within the defined applicability domain of the model;

c) the (Q)SAR result is reliable: a valid (Q)SAR that is applied to a chemical falling within its applicability domain provides a reliable result;

d) the (Q)SAR model is relevant for the regulatory purpose.

For assessment and justification of these 4 requirements the QMRF and QPRF files were developed and attached to this study record.

Description of the prediction model:

The prediction model was descripted using the harmonised template for summarising and reporting key information on (Q)SAR models. For more details please refer to the attached QSAR Model Reporting Format (QMRF) file. 

Assessment of estimation domain:

The assessment of the estimation domain was documented in the QSAR Prediction Reporting Format file (QPRF). Please refer to the attached document for the details of the prediction and the assessment of the estimation domain.

 

Conclusion

Taking into account the results of the key study, log Pow between -3.2 and -2.9, and the prediction from the KOWWIN calculation, log Pow -2.5, a log Pow value of -2.9 is is determinedto be appropriate for the chemical saftey assessment.