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Endpoint:
adsorption / desorption
Remarks:
adsorption
Type of information:
(Q)SAR
Adequacy of study:
weight of evidence
Study period:
Not applicable
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:
QSAR prediction: migrated from IUCLID 5.6
Reason / purpose:
reference to same study
Reason / purpose:
reference to other study
Qualifier:
no guideline required
Principles of method if other than guideline:
Calculations based on structure activity.
See QMRF and QPRF in "Attached background material"
GLP compliance:
no
Type of method:
other: QSAR
Specific details on test material used for the study:
Details on properties of test surrogate or analogue material (migrated information):
not applicable
Radiolabelling:
no
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, Molecular Connectivity Index
Type:
log Koc
Value:
1.974 dimensionless
Remarks on result:
other: MCI approach, KOCWIN v2.00
Key result
Type:
Koc
Remarks:
(L/kg)
Value:
94.15
Remarks on result:
other: MCI approach, KOCWIN v2.00
Details on results (HPLC method):
no data
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
Details on results (Batch equilibrium method):
Not applicable
Statistics:
Not applicable

Information for MCI and Kow approaches (KocWIN 2.0) are given through attached QMRF and QPRF documents.

Validity criteria fulfilled:
yes
Conclusions:
Koc value of CAS 106-25-2 is 94.15 L/kg. The substance is considered as highly mobile in soil.
Executive summary:

Koc value of CAS 106 -25 -2 has been assessed by using the KOCWIN v2.00 software. The results are as following:

- MCI approach; log Koc = 1.9738 , Koc (L/kg) = 94.15

Endpoint:
adsorption / desorption
Remarks:
adsorption
Type of information:
(Q)SAR
Adequacy of study:
weight of evidence
Study period:
Not applicable
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:
QSAR prediction: migrated from IUCLID 5.6
Reason / purpose:
reference to same study
Reason / purpose:
reference to other study
Qualifier:
no guideline required
Principles of method if other than guideline:
Calculations based on structure activity.
See QMRF and QPRF in "Attached background material"
GLP compliance:
no
Type of method:
other: QSAR
Specific details on test material used for the study:
Details on properties of test surrogate or analogue material (migrated information):
not applicable
Radiolabelling:
no
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, using Log Kow (input: Log Kow = 2.76)
Type:
log Koc
Value:
2.04
Remarks on result:
other: Kow approach, KOCWIN v2.00 (logKow = 2.76)
Type:
Koc
Remarks:
(L/kg)
Value:
109.7
Remarks on result:
other: Kow approach, KOCWIN v2.00 (logKow = 2.76)
Details on results (HPLC method):
no data
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
Details on results (Batch equilibrium method):
Not applicable
Statistics:
Not applicable

Information for MCI and Kow approaches (KocWIN 2.0) are given through attached QMRF and QPRF documents.

Validity criteria fulfilled:
yes
Conclusions:
Koc value of CAS 106-25-2 is 109.7 L/kg. The substance is considered as highly mobile in soil.
Executive summary:

Koc value of CAS 106 -25 -2 has been assessed by using the KOCWIN v2.00 software. The results are as following:

- Kow approach; log Koc = 2.0403, Koc (L/kg) = 109.7

Endpoint:
adsorption / desorption
Remarks:
adsorption
Type of information:
(Q)SAR
Adequacy of study:
weight of evidence
Study period:
Not applicable
Reliability:
4 (not assignable)
Rationale for reliability incl. deficiencies:
results derived from a valid (Q)SAR model and falling into its applicability domain, with limited documentation / justification
Justification for type of information:
QSAR prediction: migrated from IUCLID 5.6
Reason / purpose:
reference to same study
Reason / purpose:
reference to other study
Qualifier:
no guideline required
Principles of method if other than guideline:
Calculations based on structure activity.
GLP compliance:
no
Type of method:
other: QSAR
Specific details on test material used for the study:
Details on properties of test surrogate or analogue material (migrated information):
not applicable
Radiolabelling:
no
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:
TGD, Part III, Log Kow = 2.76 (input value)
Type:
log Koc
Value:
2.455
Remarks on result:
other: TGD, 2003, part III, table 4, Predominantly nonhydrophobics
Key result
Type:
Koc
Remarks:
(L/kg)
Value:
285
Remarks on result:
other: TGD, part III, table 4, Predominantly non hydrophobic
Details on results (HPLC method):
no data
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
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 non hydrophobics. The corresponding equation is log Koc = 0.52*log Kow + 1.02

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 non hydrophobics.

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

For non hydrophobics: n (number of data) = 390; R² (correlation coefficient) = 0.63; s.e. (standard error of estimate) = 0.56.

5.A mechanistic interpretation, if possible:

No data

Validity criteria fulfilled:
yes
Conclusions:
Koc value of CAS 106-25-2 is 285 L/kg. The substance is considered as medium mobile in soil.
Executive summary:

Koc value of CAS 106 -25 -2 has been assessed by the use of TGD Part III table 4, predominantly hydrophobic. The results are shown below:

- TGD non hydrophobic approach, log Koc = 2.4548, Koc (L/kg) = 285

Description of key information

The adsorption coefficient (log Koc) was estimated by three QSAR models:

- KOCWIN v2.00 in EPI suite (v4.0) - MCI method using log Kow

- KOCWIN v2.00 in EPI suite (v4.0) - log Kow method

- A model described in Technical Guidance on Risk Assessment (European Chemicals Bureau, 2003) - Part III, Chapter 4, table 4, equation for non hydrophobic substances.

Nerol exhibits a Koc of 143 L/kg (geometric mean of the three QSAR results: 285 L/kg, 94.15 L/kg, 109.7 L/kg).

Key value for chemical safety assessment

Koc at 20 °C:
143

Additional information

ECHA Guidance (chapter R.7.a,paragraph R.7.1.15) recommends to calculate the Koc endpoint value as the geometric mean of results obtained by means of QSAR models.

This geometric mean value is considered as the endpoint defining the substance potential for adsorption and can be used as input parameter for environmental risk assessment.

[LogKoc: 2.155]