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Endpoint:
adsorption / desorption
Remarks:
adsorption
Type of information:
read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
supporting study
Justification for type of information:
α-Pinene is a bicyclic monounsaturated monoterpene and (-)-α-pinene is an enantiomeric form of α-pinene. Therefore, data on (-)-alpha pinene can be extrapolated to alpha-pinene. (see read-across justification document in section 13).
Reason / purpose:
read-across source
Type:
log Koc
Value:
3.87 dimensionless
Remarks on result:
other: Kow approach, KOCWIN v2.00 (logKow = 4.46)
Key result
Type:
Koc
Value:
7 421 L/kg
Remarks on result:
other: Kow approach, KOCWIN v2.00 (logKow = 4.46)
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 specified
Remarks:
QSAR
Statistics:
Not applicable

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

Validity criteria fulfilled:
not applicable
Remarks:
QSAR
Conclusions:
The Koc of (-)-alpha-pinene predicted from the log Kow value is 7421.
Executive summary:

Koc has been predicted by KOCWIN v2.00 from EPISUITE 4.0 software.

The Koc of substance (-)-alpha-pinene predicted from the log Kow value is 7421 L/kg.

Endpoint:
adsorption / desorption
Remarks:
adsorption
Type of information:
read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
supporting study
Justification for type of information:
α-Pinene is a bicyclic monounsaturated monoterpene and (-)-α-pinene is an enantiomeric form of α-pinene. Therefore, data on (-)-alpha pinene can be extrapolated to alpha-pinene. (see read-across justification document in section 13).
Reason / purpose:
read-across source
Type:
log Koc
Value:
3.009 dimensionless
Remarks on result:
other: MCI approach, KOCWIN v2.00
Key result
Type:
Koc
Value:
1 020 L/kg
Remarks on result:
other: MCI approach, KOCWIN v2.00
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:
no
Statistics:
Not applicable

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

Validity criteria fulfilled:
not applicable
Remarks:
QSAR
Conclusions:
The Koc of substance (-)-alpha-pinene predicted from KOCWIN v2.00 (EPISUITE 4.0 software) is 1020 L/kg.
Executive summary:

Koc has been predicted by KOCWIN v2.00 from EPISUITE 4.0 software.

The Molecular Connectivity Index method predicted the following Koc for (-)-alpha-pinene: 1020 L/kg.

Endpoint:
adsorption / desorption
Remarks:
adsorption
Type of information:
read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
supporting study
Justification for type of information:
α-Pinene is a bicyclic monounsaturated monoterpene and (-)-α-pinene is an enantiomeric form of α-pinene. Therefore, data on (-)-alpha pinene can be extrapolated to alpha-pinene. (see read-across justification document in section 13).
Reason / purpose:
read-across source
Type:
other: log Koc
Value:
3.339 dimensionless
Remarks on result:
other: TGD, 2003, part III, table 4, Predominantly nonhydrophobics
Key result
Type:
Koc
Value:
2 184 L/kg
Remarks on result:
other: TGD, 2003, part III, table 4, Predominantly nonhydrophobics
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
Transformation products:
no

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 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
Remarks:
QSAR
Conclusions:
The Koc of (-)-alpha-pinene predicted from log Kow following equations of Sabljic and Güsten (1995) for non hydrophobic susbtances is 2184 L/Kg
Executive summary:

Koc has been predicted by calculations from log Kow using equations of Sabljic and Güsten (1995) for non hydrophobic susbtances.

The predicted Koc of (-)-alpha-pinene is 2184 L/kg.

Description of key information

Koc of alpha-pinene has been estimated by 3 QSAR methods conducted on (-)-alpha-pinene: 
1. with KOCWIN from EPISUITE 4.0 using CAS number as input and the Molecular Connectivity Method (MCI) = 1020 L/kg;
2. with KOCWIN from EPISUITE 4.0 using experimental Log Kow and CAS number as input = 7421 L/kg;
3. from experimental log Kow with equation of Sabljic and Güsten (1995) for non hydrophobic susbtances as reported in TGD (2003) = 2184 L/kg.
The geometric mean of the 3 Koc predicted values is considered for chemical safety assessment = 2547 L/kg.

Key value for chemical safety assessment

Koc at 20 °C:
2 547

Additional information

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

This geometric mean value is considered as the endpoint defining the substance for adsorption and is used as input parameter for Environmental Risk Assessment.