Lithium Citrate Tetrahydrate

Partition coefficient

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Principles of method if other than guideline:

The test method ist not indicated in the report.

GLP compliance:

no

Key result

Type:

log Pow

Partition coefficient:

-1.72

Temp.:

20 °C

Remarks on result:

other: pH not indicated

Conclusions:

A log Pow of -1.72 for citric acid is indicated in the OECD SIDS Initial Assessment Report.

Reference 2

Endpoint:

partition coefficient

Type of information:

(Q)SAR

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model, but not (completely) 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.

Principles of method if other than guideline:

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

Type of method:

calculation method (fragments)

Partition coefficient type:

octanol-water

Specific details on test material used for the study:

SMILES: O=C(O)C(O)(CC(=O)O)CC(=O)O

Key result

Type:

log Pow

Partition coefficient:

-1.67

Temp.:

25 °C

Remarks on result:

other: QSAR predicted value. The substance is not completely within the applicability domain of the model.

KOWWIN Program (v1.68) Results:

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

Log Kow(version 1.68 estimate): -1.67

 

Experimental Database Structure Match:

Name    : CITRIC ACID

CAS Num : 000077-92-9

Exp Log P: -1.64

Exp Ref : AVDEEF,A (1997)

 

SMILES : O=C(O)C(O)(CC(=O)O)CC(=O)O

CHEM  : Citric acid

MOL FOR: C6 H8 O7

MOL WT : 192.13

  

TYPE	NUM	LOGKOW FRAGMENT DESCRIPTION	COEFF	VALUE
Frag	2	-CH2-  [aliphatic carbon]	0.4911	0.9822
Frag	1	-OH    [hydroxy, aliphatic attach]	-1.4086	-1.4086
Frag	3	-COOH  [acid, aliphatic attach]	-0.6895	-2.0685
Frag	1	-tert Carbon [3 or more carbon attach]	0.2676	0.2676
Factor	1	Multi-aliphatic carboxylic acids	-0.5865	-0.5865
Factor	1	HO-C-COOH (alcohol-acid carbon)	0.3114	0.3114
Factor	2	HOOC-C-(C-COOH)(C-OH) structure correction	0.3000	0.6000
Const		Equation Constant		0.2290
Log Kow				-1.6734

 

Conclusions:

Using KOWWIN v1.68 the log Pow of citric acid was calculated to be -1.67 at 25 °C. The substance is not within the applicability domain of the model. One Fragment [-COOH] and one correction factor [(HOOC-C-(C-COOH)(C-OH)] exceed the maximum number of instances as listed in Appendix D. Thus, the estimation may be less accurate.

Executive summary:

The log Pow 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 -1.67 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

Lithium citrate and lithium citrate tetrahydrate completely dissociates in water forming lithium cation and the corresponding citrate anion. Therefore a laboratory study determining the partition coefficient is technically not feasible and the partition coefficient of citric acid is indicated.

A log Pow of -1.72 for citric acid at 20 °C is indicated in the OECD SIDS Initial Assessment Report.

Additionally, the log Pow of citric acid in water was estimated. The theoretical, calculated (EPIWIN) log Pow of citric acid is -1.67.

Key value for chemical safety assessment

Log Kow (Log Pow):

-1.72

at the temperature of:

20 °C

Additional information

Lithium citrate and lithium citrate tetrahydrate quickly dissociate in water forming lithium cation and the corresponding citrate anion. Therefore a laboratory study determining the partition coefficient is technically not feasible and the partition coefficient of citric acid was used.

In the OECD SIDS Initial Assessment Report a log Pow of -1.72 for citric acid at 20 °C is indicated.

Additionally the partition coefficient of citric acid was estimated using KOWWIN v1.68 embedded in EPI Suite v4.11 of EPA’s Office of Pollution Prevention Toxics and Syracuse Research Corporation (SRC). The program is a screening level tool and estimates the log octanol/water partition coefficient log Pow of chemicals using an atom/fragment contribution method.

Using KOWWIN v1.68 the log Pow of the test item was calculated to be -1.67 at 25 °C. The substance is not within the applicability domain of the model. One Fragment [-COOH] and one correction factor [(HOOC-C-(C-COOH)(C-OH)] exceed the maximum number of instances as listed in Appendix D. Thus, the estimation may be less accurate.