4-Penten-2-ol, 3,3-dimethyl-5-(2,2,3-trimethyl-3-cyclopenten-1-yl)-, (4E)-

Partition coefficient

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From March 12 to April 09, 2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

The study was conducted according to an internationally recognised method, and under GLP. No deviation affected the quality of the study. The test substance composition is adequately characterised. Therefore full validation applies.

Reason / purpose for cross-reference:

reference to other study

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

Principles of method if other than guideline:

Not applicable

GLP compliance:

yes (incl. QA statement)

Remarks:

inspected on September 14, 2010 / signed on February 07, 2011

Type of method:

slow-stirring method

Partition coefficient type:

octanol-water

Specific details on test material used for the study:

Storage condition of test material: Stored in container tightly closed and in a cool, well-ventilated area.

Analytical method:

liquid chromatography

mass spectrometry

Key result

Type:

log Pow

Partition coefficient:

4.99

Temp.:

25 °C

pH:

>= 5 - <= 8

Details on results:

- The average 1-octanol/water partition coefficient expressed as the log POW value of the test item determined at a temperature of 25.0 °C was 4.994 in combination with a standard error σlog POW,Av of 0.018:
log POW,Av = 4.994 ± 0.018
- The 1-octanol/water partition coefficient POW was estimated to log POW = 5.39; the deviation of the determined from this estimated value were thus -0.40.

Table 4.7/1: Equilibrium test

Equilibration time (h)	log Pow
47.00	4.999
66.50	4.984
73.25	5.010
89.25	4.978
95.00	4.995
163.25	4.996

 

The mean log Pow determined during the equilibrium test was 4.994 with a RSD of 0.23 %.

The slope was not significantly different from 0, indicating that equilibrium was already reached after 47 hours.

Table 4.7/2: Main tests

Determined log POW,i values of the experimental units
Sampling / time point	Experimental unit I	Experimental unit II	Experimental unit III
1	5.015	4.995	5.003
2	4.991	4.975	4.968
3	5.021	4.992	5.020
4	5.001	4.979	5.025
Statistical values of the logPOW,i values of the 3 experimental units
Mean, Avi	5.0068	4.9853	5.0042
Variance, VAR	0.000191	0.000096	0.000664
Standard deviation, SD	0.0138	0.0098	0.0258
Rel. standard deviation, RSD%	0.28	0.20	0.51

 

The state of equilibrium was also checked. The weighted average log Pow was calculated to be 4.994, with a weighted standard error of 0.018.

Conclusions:

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

Executive summary:

The partition coefficient (log Pow) of the test substance was measured under GLP according OECD 123 guideline, slow-stirring method.

A preliminary assay was conducted with a single vessel, to determine the equilibration time, which was reached from two days. In the main test, three vessels were prepared, and four samples were taken in each phase after equilibration at 25 °C, between 47 and 89 hours. The concentrations were measured in each phase with LC-MS/MS fully validated analysis method.

The overall average log Kow was calculated, weighted for the variance, to 4.99 (at 25°C).

Reference 2

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

December 05, 2008

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

The study was conducted according to an internationally recognised method, and under GLP. Test substance is considered adequately characterised. Validation applies, with minor restrictions due to technical inaccuracies.

Qualifier:

according to guideline

Guideline:

OECD Guideline 117 (Partition Coefficient (n-octanol / water), HPLC Method)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method A.8 (Partition Coefficient)

Deviations:

no

Principles of method if other than guideline:

Not applicable

GLP compliance:

yes (incl. QA statement)

Remarks:

Swiss GLP compliance programme (inspected on November 15 and 16, 2006 / signed on March 29, 2007

Type of method:

HPLC method

Partition coefficient type:

octanol-water

Specific details on test material used for the study:

Storage condition of test material: Refrigerator (between 0 and 10 °C under nitrogen)

Analytical method:

high-performance liquid chromatography

Type:

log Pow

Partition coefficient:

4.91

Temp.:

30 °C

pH:

6

Details on results:

Partition coefficient of sample:
Mean log10Pow: 4.91
Partition coefficient: 8.13 x 10^4
- The test material containing no dissociating functional groups, testing was therefore carried out at neutral pH.

Preliminary estimate

Approximate P_ow: 2.45 x 10⁵

Log₁₀P_owestimate: 5.39

 

Definitive test

Regression parameters: log Pow = 5.9170 x log k + 3.0388 (r = 0.9815)

 

Table 4.7/1: Partition coefficient of sample

 

	RT 1	RT 2	RT 3	RT 4	RT 5	Mean RT	STD	CV%	K	Log10K	Log10Pow
	(min)	(min)	(min)	(min)	(min)	(min)
(To) Dead time	3.89	3.89	3.89	3.89	3.89	3.89	0.00	0.00%	0.00	-	-
Test item	11.94	11.96	11.93	11.94	11.94	11.94	0.01	0.09%	2.070	0.316	4.91

 

RT = Retention time

Mean RT = = Mean retention time

STD = standard deviation

CV= coefficient of variation

Mean log10P_ow: 4.91

Partition coefficient: 8.13 x 10⁴

Conclusions:

The substance has 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 measured under GLP according to the OECD 117/EU A8 guideline, HPLC method. The system was calibrated with 6 reference substances, and the result for the sample was interpolated from the linear regression.

Partition coefficient (log P_ow) = 4.91 at 30°C.

Reference 3

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

From January 31 to October 01, 2008

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

The study was conducted according to an internationally recognised method, and under GLP. The test substance is considered adequately characterised. Validation applies, with minor restrictions due to technical inaccuracies.

Qualifier:

according to guideline

Guideline:

OECD Guideline 117 (Partition Coefficient (n-octanol / water), HPLC Method)

Deviations:

no

Principles of method if other than guideline:

Not applicable

GLP compliance:

yes (incl. QA statement)

Remarks:

UK GLP Compliance Programme (inspected on August 21, 2007/ signed on October 15, 2007)

Type of method:

HPLC method

Partition coefficient type:

octanol-water

Specific details on test material used for the study:

Storage condition of test material: Approximately 4 °C in the dark, under nitrogen.

Analytical method:

high-performance liquid chromatography

Type:

log Pow

Partition coefficient:

5.25

Temp.:

30 °C

pH:

6.5 - 6.8

Details on results:

Partition coefficient of sample:
Mean log10Pow:: 5.25
Partition coefficient: 1.77 x 10^5

Preliminary estimate:

Approximate solubility in n-octanol: >12.5 g/L

Approximate solubility in water: 1.7 x 10^-2 g/L

Approximate P_ow: >758

Log₁₀P_ow: >2.88

 

Definitive test:

Regression parameters:

Determination 1: log Pow = (log k + 0.586) / 0.253 (r = 0.985)

Determination 2: log Pow = (log k + 0.411) / 0.275 (r = 0.990)

 

Table 4.7/1: Partition coefficient of sample

 

Determination	Partition coefficient	Log10Pow	Mean Partition coefficient	Mean Log10Pow
1	1.98 x 10^5	5.30	1.77 x 10^5	5.25
2	1.56 x 10^5	5.19

Conclusions:

The substance has 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 measured under GLP according to the OECD 117/EU A8 guideline, HPLC method.The system was calibrated with 6 reference substances, and the result for the sample was interpolated from the linear regression.

Partition coefficient (log₁₀P_ow) = 5.25 at 30.0°C

Description of key information

Partition coefficient (log Kow) = 4.99 (experimental; slow-stir).
The substance has potential for bioaccumulation; the endpoint is relevant for classification according to CLP.

Key value for chemical safety assessment

Log Kow (Log Pow):

4.99

at the temperature of:

25 °C

Additional information

Three reliable studies, conducted according to recognized OECD/EC methods and under GLP, are available, and provide consistent results. Two (Safepharm 2008 and Firmenich 2009) were performed with the HPLC method, based on comparative elution versus standards, the choice of which leading to restrictions on accuracy. The more recent one (Fraunhofer 2012) was performed with the slow-stirring method, which is considered of higher quality, as based on actual phase partitioning and analysis. Therefore the slow-stirring result is prefered and retained as key data for purpose of CSA, rather than the mean value.