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Endpoint:
adsorption / desorption: screening
Type of information:
(Q)SAR
Adequacy of study:
weight of evidence
Study period:
Run on 2013-03
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
Remarks:
The value is not an experimental result, however the QSAR model is recommended by the ECHA guidance document on information requirements, is well documented with regard to validation parameters according to OECD principles. Moreover, the substance is fully characterised towards the applicability domain.
Justification for type of information:
1. SOFTWARE
EPI SuiteTM (v4.1)

2. MODEL (incl. version number)
KOCWIN v2.00

3. SMILES OR OTHER IDENTIFIERS USED AS INPUT FOR THE MODEL
O=C1CCCCCCCCC/C=C/CC(C)C1;
O=C1CCCCCCC/C=C/CCCC(C)C1;
O=C1CCCCCCCCCC/C=C\C(C)C1.

4. SCIENTIFIC VALIDITY OF THE (Q)SAR MODEL
[See attached QMRF]

5. APPLICABILITY DOMAIN
[See attached QPRF]
The substance is within the domain of the KOCWIN model based on its molecular weight and fragment presents.
Qualifier:
according to guideline
Guideline:
other: REACH guidance on QSARs R.6, May 2008
Deviations:
no
Principles of method if other than guideline:
See attached QMRF/QPRF
GLP compliance:
no
Type of method:
other: QSAR
Specific details on test material used for the study:
- log Kow : 5.52 (experimental value)
Test temperature:
Not applicable
Details on study design: HPLC method:
Not applicable
Details on sampling:
Not applicable
Details on matrix:
Not applicable
Details on test conditions:
Not applicable
Computational methods:
KOCWIN v2.00
Key result
Type:
Koc
Value:
6 182 L/kg
Remarks on result:
other: MCI method
Key result
Type:
log Koc
Value:
3.791 dimensionless
Remarks on result:
other: MCI method
Key result
Type:
Koc
Value:
14 930 L/kg
Remarks on result:
other: Kow method
Key result
Type:
log Koc
Value:
4.174 dimensionless
Remarks on result:
other: Kow method
Details on results (HPLC method):
Not applicable
Adsorption and desorption constants:
Not applicable
Recovery of test material:
Not applicable
Concentration of test substance at end of adsorption equilibration period:
Not applicable
Concentration of test substance at end of desorption equilibration period:
Not applicable
Transformation products:
not measured
Details on results (Batch equilibrium method):
Not applicable
Statistics:
Not applicable

Koc estimate from MCI:

First order Molecular Connectivity Index : ......................8.288

Non-corrected log Koc (0.5213 MCI + 0.60) : ...............4.9202

Fragment correction(s) : 1 Ketone (-C-CO-C-): ...........-1.1290

Corrected log Koc : ............................................................3.7911

Estimated Koc = 6182 L/Kg

Koc estimate frol Log Kow:

Log Kow (used entered): ............................................................5.52

Non-corrected log Koc (0.55313 log Kow + 0.9251): ............3.9784

Fragment correction(s): 1 Ketone (-C-CO-C-): .......................0.1956

Corrected log Koc: .......................................................................4.1740

Estimated Koc = 14930 L/Kg

Validity criteria fulfilled:
yes
Conclusions:
The estimated adsorption coefficient were 6182 L/kg (log Koc = 3.79) and 14930 L/kg (log Koc = 4.17), calculated from the MCI and log Kow methodologies respectively, with an experimental log Kow value at 5.52.
Executive summary:

The adsorption coefficient (Koc) of the substance was estimated using the KOCWIN v2.00 QSAR model available from the US EPA.

The estimated adsorption coefficient were 6182 L/kg (log Koc = 3.79) and 14930 L/kg (log Koc = 4.17), calculated from the MCI and log Kow methodologies respectively, with an experimental log Kow value at 5.52.

Endpoint:
adsorption / desorption: screening
Type of information:
calculation (if not (Q)SAR)
Adequacy of study:
weight of evidence
Study period:
Run on 2013-03
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 limited documentation / justification
Remarks:
The value is not an experimental result, however the derivation of Koc from Kow values as described in the TGD (2003) is reported as a usable valid model by ECHA, which fulfilled all OECD principles.
Justification for type of information:
1. SOFTWARE
None. Technical Guidance Document (2003)

2. MODEL (incl. version number)
None.

3. SMILES OR OTHER IDENTIFIERS USED AS INPUT FOR THE MODEL
LOG KOW: 5.52 (experimental value)

4. SCIENTIFIC VALIDITY OF THE (Q)SAR MODEL
See details in the Endpoint Study Record

5. APPLICABILITY DOMAIN
See details in the Endpoint Study Record

6. ADEQUACY OF THE RESULT
See details in the Endpoint Study Record
Qualifier:
according to guideline
Guideline:
other: REACH guidance on QSARs R.6, May 2008
Deviations:
no
Principles of method if other than guideline:
See "Any other information on results incl. tables".
GLP compliance:
no
Type of method:
other: QSAR
Specific details on test material used for the study:
- log Kow : 5.52 (experimental result)
Test temperature:
Not applicable
Details on study design: HPLC method:
Not applicable
Details on sampling:
Not applicable
Details on matrix:
Not applicable
Details on test conditions:
Not applicable
Computational methods:
Not applicable
Key result
Type:
log Koc
Value:
4.571 dimensionless
Remarks on result:
other: Chemical class: Predominantly hydrophobics; log Koc = 0.81*log Kow + 0.10
Details on results (HPLC method):
Not applicable
Adsorption and desorption constants:
Not applicable
Recovery of test material:
Not applicable
Concentration of test substance at end of adsorption equilibration period:
Not applicable
Concentration of test substance at end of desorption equilibration period:
Not applicable
Transformation products:
not measured
Details on results (Batch equilibrium method):
Not applicable
Statistics:
Not applicable

The derivation of Koc from Kow values as described in the TGD (2003) is reported as a usable valid model by ECHA, which fulfilled all OECD principles:

1.A defined endpoint:

Adsorption coefficient (Koc).

2. An unambiguous algorithm:

19 models have been developed for different chemical classes (see table 4 of the TGD part III). The chemical class “predominantly hydrophobics” is defined as compounds containing only carbon, hydrogen and halogen (F, Cl, Br, I) atoms, “nonhydrophobic chemicals” being all chemicals that cannot be classified as predominantly hydrophobics. Fourteen class-specific QSAR models were produced for all nonhydrophobic classes of chemicals, in order to give more appropriate equations. The test substance is considered pred ominantly hydrophobics. The corresponding equation is log Koc = 0.81*log Kow + 0.10

3.A defined domain of applicability:

The applicability domain of the sorption models developed by Sabljic and Güsten (1995) depends on the considered chemical class, and is based on logKow range (see table 5 of the TGD part III). The substance is within the validity domain of predominantly hydrophobics.

4.Appropriate measures of goodness-of-fit, robustness and predictivity:

For predominantly hydrophobics: n (number of data) = 81; R² (correlation coefficient) = 0.89; s.e. (standard error of estimate) = 0.45.

5.A mechanistic interpretation, if possible:

No data

Validity criteria fulfilled:
not applicable
Conclusions:
The estimated adsorption coefficient of the substance is 37 256 L/kg (log Koc = 4.57), with an experimental log Kow at 5.52.
Executive summary:

The derivation of Koc from Kow values as described in the TGD (2003) is reported as a usable valid model by ECHA, which fulfilled all OECD principles. Based on the chemical class of predominantly hydrophobics, the estimated adsorption coefficient of the substance is 37 256 L/kg (log Koc = 4.57), with an experimental log Kow at 5.52.

Description of key information

Weight of Evidence approach, geometric mean of QSAR/calculated results:

Koc =  15 094 L/Kg

log Koc = 4.18

Immobile in soils (according to P.J. McCall et al., 1980).

Key value for chemical safety assessment

Koc at 20 °C:
15 094

Additional information

The adsorption coefficient of the substance was determined using two valid QSAR, recommended by the ECHA guidance document on information requirements. The first model is KOCWIN v2.00, available from the US EPA. The adsorption coefficient (Koc) was estimated to be 6182 L/kg (log Koc = 3.79) and 14930 L/kg (log Koc = 4.17), calculated from the MCI and log Kow methodologies respectively, using an experimental log Kow value at 5.52. The second model is TGD (2003). Based on the chemical class of predominantly hydrophobics, the estimated adsorption coefficient of the substance is 37 256 L/kg (log Koc = 4.57), with an experimental log Kow at 5.52.

In conclusion, the Koc of the substance is estimated to be 15094 L/kg, corresponding to a log Koc at 4.18 (geometric mean of QSAR results).

Considering the sensitivity analysis of log Koc on PEC and RCR, the expected likely variation interval of an experimental log Koc determination and that the risk would remain acceptable, it is not deemed relevant to perform any experimental study (see attached report for details).

[LogKoc: 4.18]