5-hept-6-enyloxolan-2-one

Partition coefficient

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

partition coefficient

Type of information:

(Q)SAR

Adequacy of study:

supporting study

Study period:

09-19 November 2021

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
iSafeRat® – in Silico Algorithms For Environmental Risk And Toxicity

2. MODEL (incl. version number)
iSafeRat® KOW v1.9

3. SMILES OR OTHER IDENTIFIERS USED AS INPUT FOR THE MODEL
O=C1CCC(CCCCCC=C)O1

4. SCIENTIFIC VALIDITY OF THE (Q)SAR MODEL
See attached QMRF for further details.

5. APPLICABILITY DOMAIN
See attached QMRF/Study Report for further details.

6. ADEQUACY OF THE RESULT
See attached Study Report for further details.

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 123 (Partition Coefficient (1-Octanol / Water), Slow-Stirring Method)

Deviations:

not applicable

Remarks:

QSAR model

Qualifier:

equivalent or similar to guideline

Guideline:

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

Deviations:

not applicable

Remarks:

QSAR model

Principles of method if other than guideline:

The OCTANOL/WATER PARTITION COEFFICIENT (LOG KOW) was determined using the iSafeRat® KOW, a validated QSAR model. The model uses a core-centred substitution method (C2SM) in which the molecule is divided a core and substituents and each fragment is related to a specific contribution of log KOW which may be positive or negative. The final log KOW is determined by simple addition of the fragments. The QSAR is based on validated data log KOW values from high quality experimental studies generally using the shake-flask method but slow-stir values have been used when available. The results are considered to be as accurate as those from a good quality OECD 107 or 123 study.

GLP compliance:

no

Remarks:

QSAR model

Type of method:

other: QSAR model

Partition coefficient type:

octanol-water

Analytical method:

other: QSAR model

Type:

log Pow

Partition coefficient:

2.8

Temp.:

25 °C

Remarks on result:

other: no ionisation expected for pH between 0 to 14

Details on results:

No uncertainty estimation is provided.

Applicability Domain
The model methodology is based on structural analysis only.All the required fragment contribution values were available from the iSafeRat® log KOW module. Since no missing fragments were identified, the constituents of the test item are within the structural fragment domain of the model. Further details are provided within the QPRF documents.

Conclusions:

This QSPR model has been validated as a QSAR model to be compliant with the OECD recommendations for QSAR modeling (OECD, 2004) in as much as this is possible for this model. The test item falls within the applicability domain of the model and was therefore reliably predicted for its log KOW. Therefore, this endpoint value can be considered valid and fit for purpose.

Executive summary:

A Quantitative Structure-Property Relationship (QSPR) model was used to calculate the OCTANOL/WATER PARTITION COEFFICIENTS (LOG KOW) of the test item. This QSPR model has been validated as a Quantitative Structure-Analysis Relationship (QSAR) model to be compliant with the OECD recommendations for QSAR modeling (OECD, 2004) and predicts the endpoint value which would be expected when testing the substance under experimental conditions in a laboratory following the Organisation for Economic Cooperation and Development (OECD) Guideline for Testing of Chemicals No. 107, "Partition Coeficient (noctanol/water): Shake Flask Method" (OECD, 1995) and No. 123 "Partition Coeficient (n-octanol/water): Slow Stirring Method” (OECD, 2006). The criterion predicted was the log KOW (also known as log POW).

 

The OCTANOL/WATER PARTITION COEFFICIENT (LOG KOW) was determined using the iSafeRat® KOW, a validated QSAR model. The model uses a core-centred substitution method (C2SM) in which the molecule is divided a core and substituents and each fragment is related to a specific contribution of log KOW which may be positive or negative. The final log KOW is determined by simple addition of the fragments. The QSAR is based on validated data log KOW values from high quality experimental studies generally using the shake-flask method but slow-stir values have been used when available. The results are considered to be as accurate as those from a good quality OECD 107 or 123 study.

 

This QSPR model has been validated as a QSAR model to be compliant with the OECD recommendations for QSAR modeling (OECD, 2004) in as much as this is possible for this model. The test item falls within the applicability domain of the model and was therefore reliably predicted for its log K_OW. Therefore, this endpoint value can be considered valid and fit for purpose.

 

The OCTANOL/WATER PARTITION COEFFICIENT (LOG KOW) of the test item was determined as 2.8 at 25°C.

 

No uncertainty estimation is provided

Reference 2

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Test dates: April 22, 2005 to August 3, 2005

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Justification for type of information:

The GLP study was not conducted according to an internationally recognised method, and under GLP. A lower number of points were used for calibration. References substance not between the ones reccommended in the guidance. The substance is adequately identified. Besides a mixture of THF/water was used as eluent. Therefore validation applies with restrictions.

Qualifier:

according to guideline

Guideline:

EU Method A.8 (Partition Coefficient - HPLC Method)

Deviations:

not specified

Principles of method if other than guideline:

Not applicable

GLP compliance:

yes (incl. QA statement)

Remarks:

GIPC: effective Sep.3, 2004, signed on Nov.05, 2004, effective since 5 November 2004

Type of method:

HPLC method

Partition coefficient type:

octanol-water

Analytical method:

high-performance liquid chromatography

Key result

Type:

log Pow

Partition coefficient:

2.66

Temp.:

20 °C

Remarks on result:

other: pH not recorded

Calibration Curve:

 

Calculation of regression curve gave:

 

log Kow = 5.678 (± 0.082) log (k) + 2.819 (±0.011) 

r2 (coefficient of determination) = 0.9973

 

where:

k = capacity factor

Kow= coefficient of ripartition n-octanol/water

 

The raw data of the analysis of the sample solution are reported here after:

 

Retention time, tr (min)			Replicate value of k*			log (Mean k)
1	2	3	1	2	3
8.17	8.17	8.18	0.94	0.94	0.94	-0.03

(*) Mean value of the dead time was 4.22, as mean from replicate injections of the calibration solutions.

Log Kow (at 95% of confidence) = 2.66 [2.57 - 2.75].

Conclusions:

The substance has low potential to bioaccumulate in the environment, according to CLP classification criteria for aquatic chronic toxicity (log Kow <4 ).

Executive summary:

The partition coefficient of the test substance was determined under GLP according to EU A.8 guideline, HPLC method.

Determinations were conducted in triplicate for a solvents ratio (60:40; 3 replicates each). Concentrations were measured using a HPLC validated method.

The log Pow was determined to be 2.66.

Description of key information

Partition coefficient (log Kow) = 2.66 (EU A8, HPLC method; GLP)

 

Key value for chemical safety assessment

Log Kow (Log Pow):

2.66

at the temperature of:

20 °C

Additional information

A reliable GLP experimental study, conducted according to a comparable EC method is available. Some restrictions apply on test conditions so a QSAR estimation was performed to confirm the experimental result.

The LogKow was reliably estimated by QSAR. The calculated (QSAR) LogKow confirmed the experimental logKow which is retained as key value.