Oct-2-ene

Adsorption / desorption

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

adsorption / desorption: screening

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:

(Q)SAR prediction

Qualifier:

no guideline followed

Principles of method if other than guideline:

Parameter estimation by QSAR, using KOCW v 2.00, a model within EPI Suite version 4.11, from the U.S. Environmental Protection Agency (EPA), a validated QSAR program which is part of the OECD (Q)SAR Toolbox.

GLP compliance:

no

Remarks:

Not applicable.

Key result

Type:

Koc

Remarks:

Estimate

Value:

8 200 L/kg

Remarks on result:

other: KOC Estimate

Remarks:

Estimated using the “KOC Estimate from log Kow” module within KOCWIN v 2.00 from EPI Suite based on experimental database log Kow=4.51.

Key result

Type:

log Koc

Remarks:

Estimate

Value:

3.914 dimensionless

Remarks on result:

other: log KOC Estimate

Remarks:

Estimated using the “KOC Estimate from log Kow” module within KOCWIN v 2.00 from EPI Suite based on experimental database log Kow = 4.51

Type:

Koc

Remarks:

Estimate

Value:

436.8 L/kg

Remarks on result:

other: KOC Estimate/Estimated using the “KOC Estimate from MCI” module within KOCWIN v 2.00 from EPI Suite

Type:

log Koc

Remarks:

Estimate

Value:

2.64 dimensionless

Remarks on result:

other:

Remarks:

log KOC Estimate/Estimated using the “KOC Estimate from MCI” module within KOCWIN v 2.00 from EPI Suite

Validity criteria fulfilled:

yes

Remarks:

Validated QSAR, part of the OECD (Q)SAR Toolbox

Conclusions:

The adsorption/desorption coefficient (Koc) of the substance was estimated to be 8,200 L/kg (log Koc = 3.9138), as predicted by the “Koc Estimate from Log Kow” module using a user entered log Kow of 4.51, an experimentally-determined value cited by EPI Suite.. This estimate is somewhat different but generally similar to the estimated Koc of 436.8 L/kg (log Koc = 2.6403), as predicted by the “Koc Estimate from Molecular Connectivity Index (MCI)” module. The “Koc Estimate from Log Kow” module using an experimentally determined log Kow of 4.51 was selected as the key value, since it was based on experimental data rather than an estimate. The key predicted Koc value indicates that the substance exhibits high sorption onto soil and sediment.

Reference 2

Endpoint:

adsorption / desorption, other

Remarks:

adsorption

Type of information:

(Q)SAR

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: TGD guideline, QSAR calculation, acceptable with restrictions

Justification for type of information:

Read-across between the target substance Oct-2-ene (EC 203-894-2 / CAS 111-67-1) and source substances Octene (EC 246-920-8 / CAS 25377-83-7) and Oct-1-ene (EC 203-893-7 / CAS 111-66-0 / alpha-C8) is based upon the similarity of the chemical structures and their respective physico-chemical properties. The ECHA Read-Across Assessment Framework (RAAF) states that substances with qualitatively similar properties can form the basis of read-across in circumstances where the source and target substances share such similar characteristics.
Octene, Oct-1-ene and Oct-2-ene are linear olefins, each with a carbon chain length of C8. Structurally, the difference between source and target substances is the position of the carbon-carbon double bond. For Oct-1-ene the double bond is at the terminal C1 position (hence, an alpha-olefin), whereas for Oct-2-ene the double bond is at the non-terminal C2 position (hence, an internal olefin). A comparison of the target and source substance properties shows that both substances would be expected to exhibit similar environmental fate, ecotoxicological and mammalian toxicological behaviours. The justification for this read-across from source substances Octene and Oct-1-ene to target substance Oct-2-ene is detailed in section 13 (Document name: “Oct-2-ene Read Across Document HOPA”).
Further, Oct-2-ene and Oct-1-ene both fit within the boundaries of the chemical category of higher olefins. Studies conducted by the HOPA consortium on a large range of higher olefin category members (including Oct-1-ene) demonstrated sufficiently similar physico-chemical, environmental fate and toxicological properties to substantiate the basis for read-across. Therefore Oct-2-ene is expected to behave similarly. Justification for inclusion of Oct-2-ene within the boundaries of the higher olefins category, and the relevance of each category member as an analogue substance to Oct-2-ene, is provided in Section 13 (Document name: “HOPA Higher Olefins CJD with Category Matrix Report [rev 1 Sept 2016]”).

Reason / purpose for cross-reference:

read-across: supporting information

Principles of method if other than guideline:

This equation is based on linear regression analysis and log Kow as descriptor variable with the assumption of an equilibrium state. Sablijic and Gusten developed separate equations for different classes of chemicals. The equation for hydrophobics has been used here.

GLP compliance:

no

Remarks:

not applicable

Type of method:

other: calculation

Media:

soil

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:

not applicable

Type:

log Koc

Value:

3.7 dimensionless

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

Details on results (Batch equilibrium method):

not applicable

Statistics:

not applicable

Based on a log Kow of 4.47

Validity criteria fulfilled:

not applicable

Conclusions:

The calculated log Koc is 3.7

Executive summary:

An experimental log Koc is not available for 1 -octene. In the absence of measured data the use of a QSAR to predict the log Koc is an appropriate technique to use. The use of the soil and sediment sorption QSAR for hydrophobics recommended in the Technical Guidance Document (2003) is appropriate for 1 -octene as its log Kow falls within the applicability domain of the model.

Reference 3

Endpoint:

adsorption / desorption, other

Remarks:

adsorption

Type of information:

(Q)SAR

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: TGD guideline, QSAR calculation, acceptable with restrictions

Justification for type of information:

Read-across between the target substance Oct-2-ene (EC 203-894-2 / CAS 111-67-1) and source substances Octene (EC 246-920-8 / CAS 25377-83-7) and Oct-1-ene (EC 203-893-7 / CAS 111-66-0 / alpha-C8) is based upon the similarity of the chemical structures and their respective physico-chemical properties. The ECHA Read-Across Assessment Framework (RAAF) states that substances with qualitatively similar properties can form the basis of read-across in circumstances where the source and target substances share such similar characteristics.
Octene, Oct-1-ene and Oct-2-ene are linear olefins, each with a carbon chain length of C8. Structurally, the difference between source and target substances is the position of the carbon-carbon double bond. For Oct-1-ene the double bond is at the terminal C1 position (hence, an alpha-olefin), whereas for Oct-2-ene the double bond is at the non-terminal C2 position (hence, an internal olefin). A comparison of the target and source substance properties shows that both substances would be expected to exhibit similar environmental fate, ecotoxicological and mammalian toxicological behaviours. The justification for this read-across from source substances Octene and Oct-1-ene to target substance Oct-2-ene is detailed in section 13 (Document name: “Oct-2-ene Read Across Document HOPA”).
Further, Oct-2-ene and Oct-1-ene both fit within the boundaries of the chemical category of higher olefins. Studies conducted by the HOPA consortium on a large range of higher olefin category members (including Oct-1-ene) demonstrated sufficiently similar physico-chemical, environmental fate and toxicological properties to substantiate the basis for read-across. Therefore Oct-2-ene is expected to behave similarly. Justification for inclusion of Oct-2-ene within the boundaries of the higher olefins category, and the relevance of each category member as an analogue substance to Oct-2-ene, is provided in Section 13 (Document name: “HOPA Higher Olefins CJD with Category Matrix Report [rev 1 Sept 2016]”).

Reason / purpose for cross-reference:

read-across: supporting information

Principles of method if other than guideline:

This equation is based on linear regression analysis and log Kow as descriptor variable with the assumption of an equilibrium state. Sablijic and Gusten developed separate equations for different classes of chemicals. The equation for hydrophobics has been used here.

GLP compliance:

no

Remarks:

not applicable

Type of method:

other: calculation

Media:

soil

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:

not applicable

Type:

log Koc

Value:

3.38 dimensionless

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

Details on results (Batch equilibrium method):

not applicable

Statistics:

not applicable

Based on a log Kow of 4.05

Validity criteria fulfilled:

not applicable

Conclusions:

The calculated log Koc is 3.38

Executive summary:

An experimental log Koc is not available for octene. In the absence of measured data the use of a QSAR to predict the log Koc is an appropriate technique to use. The use of the soil and sediment sorption QSAR for hydrophobics recommended in the Technical Guidance Document (2003) is appropriate for octene as its log Kow falls within the applicability domain of the model.

Description of key information

The adsorption/desorption coefficient (Koc) of the substance was predicted to be 8,200 L/kg (i.e., log Koc of 3.9138) based upon the Estimate from Log Kow method by KOCWIN v2.00, a model within EPI Suite. The estimate was based upon a directly measured value for octanol-water partition coefficient (log Kow = 4.51) as cited in the model. The predicted Koc indicates that the substance exhibits significant sorption onto soil and sediment.

Key value for chemical safety assessment

Koc at 20 °C:

8 200

Additional information

The key value for adsorption coefficient was based upon an estimate of the adsorption coefficient obtained from KOCWIN v2.00, a model within EPI Suite v4.11, from the U.S. Environmental Protection Agency (EPA), a validated QSAR program which is part of the OECD (Q)SAR Toolbox. Additional QSAR predictions of the adsorption coeffcient were provided by two supporting studies using the equation of Sabljic and Gusten: a prediction for octene or C8 (CAS 25377-83-7), based upon an input value of log Kow = 4.05, and resulting in a predicted value of log Koc = 3.38; and a prediction for oct-1-ene or alpha-C8 (CAS 111-66 -0), based upon an input value of log Kow = 4.47, and resulting in a predicted value of log Koc = 3.7. The predicted values from the supporting studies are similar to the predicted value for the key study, and indicate significant sorption onto soil and sediment.