Lavender, Lavandula angustifolia, ext.

Partition coefficient

Link to relevant study record(s)

Reference

Endpoint:

partition coefficient

Type of information:

(Q)SAR

Adequacy of study:

weight of evidence

Study period:

run on 2016-12-28

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

Justification for type of information:

QSAR prediction: 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.

Reason / purpose for cross-reference:

reference to other study

Principles of method if other than guideline:

QSAR estimation

Partition coefficient type:

octanol-water

Specific details on test material used for the study:

Input: SMILE notation: CC(=CCC=C(C)C=C)C

Type:

log Pow

Partition coefficient:

4.8

Remarks on result:

other: pH and temperature not reported

Temperature and pH values are not considered in this model.

The estimation is based on the non-ionised form of the molecule.

TYPE	NUM	LOGKOW FRAGMENT DESCRIPTION	COEFF	VALUE
Frag	3	-CH3   [aliphatic carbon]	0.5473	1.6419
Frag	1	-CH2-  [aliphatic carbon]	0.4911	0.4911
Frag	1	=CH2 [olefinic carbon]	0.5184	0.5184
Frag	5	=CH- or =C< [olefinic carbon]	0.3836	1.9180
Const		Equation Constant		0.2290
			Log Kow  =	4.7984

No Experimental Value Adjustment was made.

The molecular weight of the test substance is 136.24 g/mol, hence within the estimation domain of the validation set (27.03 -991.15 g/mol), all the functional groups are included in the list of descriptors, and the occurence of each fragment is below the maximum number in the training/validation sets (Appendix D).

		Training Set		Validation Set
Fragment Descriptor	Coef	Max	Number	Max	Number
-CH3    [aliphatic carbon]	0.5473	13	1401	20	7413
-CH2-   [aliphatic carbon]	0.4911	18	1083	28	7051
=CH2 [olefinic carbon]	0.5184	2	50	4	235
=CH- or =C< [olefinic carbon]	0.3836	10	239	10	1847

Conclusions:

Log Kow = 4.80 (estimated by QSAR)
The substance should have potential for bioaccumulation and should be taken into account for PBT assessment.

Executive summary:

The partition coefficient of the test substance was estimated using the recommended QSAR model KOWWIN v1.68, based on Atom/Fragment Contribution (AFC) method. The substance is within the applicability domain (MW, descriptors).

The calculated result is log Kow = 4.80, with a standard deviation provided by the model of 0.48.

Description of key information

The partition coefficient of the test substance was estimated using the recommended QSAR model KOWWIN v1.68, based on Atom/Fragment Contribution (AFC) method. The substance is within the applicability domain (MW, descriptors).

The calculated result is log Kow = 4.80, with a standard deviation provided by the model of 0.48.

Key value for chemical safety assessment

Log Kow (Log Pow):

4.8