Benzenesulfonic acid, 4-C20-24 (even numbered) sec-alkyl derivs., sodium salts

Partition coefficient

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

partition coefficient

Type of information:

(Q)SAR

Adequacy of study:

key study

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:

1. SOFTWARE
EPI Suite KOWWIN

2. MODEL (incl. version number)
v1.68

3. SMILES OR OTHER IDENTIFIERS USED AS INPUT FOR THE MODEL
Where applicable, the following conditions were entered into the methods.
Molecular formula: C30 H54 O3 S1 Na1
SMILES Notation: CCCCCCCCCCCCCCCCCCCCCC(CC)C1=CC=C(C=C1)S(=O)(=O)[O-].[Na+]

4. SCIENTIFIC VALIDITY OF THE (Q)SAR MODEL
It was not possible to determine the partition coefficient experimentally. The partition coefficient was estimated by using quantitative structure-activity relationship (QSAR) methods.
Full details can be find in the software package KOWWIN v1.68, US Environmental Protection Agency. Office of Chemical Safety and Pollution Prevention, 1200 Pennsylvania Ave, N.W. Washington DC, 20460-0001, USA. The model applies the following methodology to generate predictions:
- Atom/fragment contribution method
- The model and the training and validation sets are published by US Environmental Protection Agency (USA). The experimental Log Kow values in the training set and validation set were measured using one or more methods equivalent or similar to the following guidelines:
- Shake Flask method (OECD TG 107)
- HPLC method (OECD TG 117)
- Slow Stirring method (OECD TG 123)
- Relevant EU (1992 as amended) and US EPA OPPTS (1982 as amended) and ASTM (1993) methods may be also used where appropriate.
A full list of experimental Log Kow reference citations is provided in the KOWWIN help menu with additional reference citations.


5. APPLICABILITY DOMAIN
The applicability domain of the model can be described based on the training and test (external validation) set it was developed on:

Data Minimum molecular weight Maximum molecular weight Number of instances Average MW
Training set 18.02 719.92 2447 199.98
Test (external validation) set 27.03 91.15 10946 259.98

The molecular weight of the test substance is 502 which falls within the boundaries of the training set.


6. ADEQUACY OF THE RESULT
Substance falls within the boundaries of the model.

Principles of method if other than guideline:

The partition coefficient of the test substance was estimated using EPI Suite v4.11 QSAR method.

Key result

Type:

log Pow

Partition coefficient:

8.82

Remarks on result:

other: pH and temperature not reported

Details on results:

Although no temperature and pH were reported it can be assumed that the data reflects ambient temperature and neutral pH.

 Log Kow(version 1.68 estimate): 8.82

SMILES : CCCCCCCCCCCCCCCCCCCCCC(CC)c1ccc(cc1)S(=O)(=O)O([Na])

CHEM   :

MOL FOR: C30 H53 O3 S1 Na1

MOL WT : 516.81

-------+-----+--------------------------------------------+---------+--------

TYPE  | NUM |        LOGKOW FRAGMENT DESCRIPTION         |  COEFF  |  VALUE

-------+-----+--------------------------------------------+---------+--------

Frag  |  2  |  -CH3    [aliphatic carbon]                | 0.5473  |  1.0946

Frag  | 21  |  -CH2-   [aliphatic carbon]                | 0.4911  | 10.3131

Frag  |  1  |  -CH     [aliphatic carbon]                | 0.3614  |  0.3614

Frag  |  6  |  Aromatic Carbon                           | 0.2940  |  1.7640

Frag  |  1  |  -SO2-O [sulfonate, aromatic attach]       |-0.3650  | -0.3650

Factor|  1  |  S-O-{Na,K,Li}   [coef*(1+0.3*(NUM-1))]    |-4.5800  | -4.5800

Const |     |  Equation Constant                         |         |  0.2290

-------+-----+--------------------------------------------+---------+--------

                                                        Log Kow   =   8.8171

Conclusions:

The partition coefficient was estimated by using quantitative structure-activity relationship (QSAR) methods. The partition coefficient estimated from the EPI Suite v4.11 QSAR method conducted was 8.82.

Reference 2

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

20 July 2018 – 23 July 2018

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

Formal testing could not be conducted as the test substance is immiscible in water. Therefore, estimation by visual solubilities is reported

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method A.8 (Partition Coefficient)

Deviations:

no

GLP compliance:

yes

Type of method:

flask method

Partition coefficient type:

octanol-water

Specific details on test material used for the study:

- Batch n°: 2712-106
- Analytical purity: 100%
- Expiration date: not indicated
- Storage condition: at room temperature

Key result

Type:

log Pow

Partition coefficient:

>= 1.7

Remarks on result:

other: As the test item was immiscible in water, formal testing could not be determined. Therefore, estimation by visual solubilities has been reported. No temperature or pH is reported

Table: Estimation of partition coefficient

Solvent	Mass of sample (mg)		Solvent volume (ml)		Predicted solubility (mg.L-1)		Log P
Water	10		1000		< 10		> 1.3
Octanol	4.98		10		498

Conclusions:

The partition coefficient (log Pow) of the test item was determined to be => 1.7.

Description of key information

Based on a GLP guideline study (Dekra, 2018) using the shake flask method according to EU method A.8 and OECD guideline 107, the partition coefficient (log Pow) of the test item was determined to be >= 1.7. Formal testing could not be conducted as the test substance is immiscible in water. Therefore, an unbounded value as estimation from the visual solubilities is reported and the study was assigned to be reliable with restrictions (K2) and considered to be a supporting study.

The partition coefficient was estimated by using quantitative structure-activity relationship (QSAR) methods. The partitioncoefficient estimate from the EPI Suite v4.11 QSAR method conducted was 8.82 (high log Pow) which is considered reliable with restrictions (K2) in a key approach.

Key value for chemical safety assessment

Log Kow (Log Pow):

8.82