O-phosphoserine

Partition coefficient

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

partition coefficient

Data waiving:

study technically not feasible

Justification for data waiving:

other:

Reference 2

Endpoint:

partition coefficient

Type of information:

(Q)SAR

Adequacy of study:

supporting study

Study period:

2017

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model and falling into its applicability domain, with adequate and reliable documentation / justification

Justification for type of information:

Please refer to the QMRF and QPRF files provided under the section attached justification.

Qualifier:

according to guideline

Guideline:

other: REACH guidance on QSAR R.6

Principles of method if other than guideline:

Estimates the log octanol-water partition coefficient, log KOW, of chemicals using an atom/fragment contribution method.

GLP compliance:

no

Type of method:

calculation method (fragments)

Partition coefficient type:

octanol-water

Specific details on test material used for the study:

SMILES: OC(=O)C(N)COP(O)(O)=O

Key result

Type:

log Pow

Partition coefficient:

-4.54

Temp.:

25 °C

Remarks on result:

other: QSAR predicted value. The substance is within the applicability domain of the model.

SMILES : OC(=O)C(N)COP(O)(O)=O

CHEM  : O-Phospho-L-Serine

MOL FOR: C3 H8 N1 O6 P1

MOL WT : 185.07

 

KOWWIN Program (v1.68) Results:

===============================

 

Log Kow(version 1.68 estimate): -4.54

 

SMILES : OC(=O)C(N)COP(O)(O)=O

CHEM  : O-Phospho-L-Serine

MOL FOR: C3 H8 N1 O6 P1

MOL WT : 185.07

 

TYPE	NUM	LOGKOW FRAGMENT DESCRIPTION	COEFF	VALUE
Frag	1	-CH2-  [aliphatic carbon]	0.4911	0.4911
Frag	1	-CH    [aliphatic carbon]	0.3614	0.3614
Frag	1	-NH2   [aliphatic attach]	-1.4148	-1.4148
Frag	1	-COOH  [acid, aliphatic attach]	-0.6895	-0.6895
Frag	1	-O-P   [aliphatic attach]	-0.0162	-0.0162
Frag	1	O=P	-2.4239	-2.4239
Frag	2	-OH [phosphorus attach]	0.4750	0.9500
Factor	1	Amino acid (alpha-position) correction	-2.0238	-2.0238
Const		Equation Constant		0.2290

 

NOTE |    | Zwitterionic calculation made for all Amino Acids  |

 

Log Kow  = -4.5367

Conclusions:

Using KOWWIN v1.68 the logPow of the test item was calculated to be -4.54 at 25 °C. The substance is within the applicability domain of the model.

Executive summary:

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 -4.54 at 25 °C (EPI Suite, 2014).

 

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.

Description of key information

The predicted log Pow value is out of the applicability domain of any OECD method. Thus, the study is technically not feasible.

Additional information

In accordance with REACH Annex XI section 2, the study was not performed as the estimated log Pow is below the applicability range of the OECD TG 107, 117 and 123 according to ECHA guidance on IR/CSA R7.a, table R 7.1 -6. A QSAR estimation was performed with the test item. The predicted log Pow value was -4.54 which is out of the applicability domain of any OECD method. Thus, the study is technically not feasible.