(3R,5Z)-3-METHYL-5-CYCLOPENTADECEN-1-ONE

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:

2012-11-22 to 2013-01-28

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 with its purity. Therefore full validation applies.

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

(March 23, 2006)

GLP compliance:

yes (incl. QA statement)

Remarks:

Inspected on 14 September 2010 / Signed on 07 February 2011

Type of method:

slow-stirring method

Partition coefficient type:

octanol-water

Analytical method:

liquid chromatography

Key result

Type:

log Pow

Partition coefficient:

5.522

Temp.:

25 °C

pH:

>= 6 - <= 8.3

Equilibrium test

Equilibration time (h)	log Pow
24.00	5.597
29.50	5.568
46.17	5.560
52.25	5.543
70.00	5.552

The mean log Pow determined during the equilibrium test was 5.564 with a RSD of 0.37%. The slope was not significantly different from 0, indicating that equilibrium was already reached after 24 hours.

Main tests

Measured log Pow
Sampling time (h)	Vessel 1	Vessel 2	Vessel 3
66.58	5.525	5.509	5.510
73.25	5.550	5.522	5.513
90.50	5.560	5.521	5.545
96.58	5.543	5.530	5.515
116.3	5.519	5.499	5.497
Statistical values
Mean log Pow	5.5393	5.5161	5.5159
Variance	0.00029	0.000153	0.000309
SD	0.0171	0.0124	0.0176
RSD (%)	0.31	0.22	0.32

The state of equilibrium was also checked.

The weighted average log Pow was calculated to be 5.522, with a weighted standard error of 0.019.

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 24 hours. In the main test, three vessels were prepared, and five samples were taken in each phase after equilibration at 25°C, between 66 and 116 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 5.52.

Reference 2

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

2010-01-11 to 2010-01-20

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 with its purity. Therefore full validation applies.

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

13thApril 2004

Qualifier:

according to guideline

Guideline:

EU Method A.8 (Partition Coefficient)

Version / remarks:

Council Regulation (EC) No 440/2008 dated 30 May 2008

Deviations:

yes

Remarks:

log Kow value for reference substance DDT

GLP compliance:

yes (incl. QA statement)

Remarks:

Inspected on 04th and 05th May 2009 / Signed on 1st September 2009

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:

6.32

Temp.:

30 °C

pH:

6

Key result

Type:

log Pow

Partition coefficient:

6.16

Remarks on result:

other: recalculated

Preliminary estimate

A preliminary assessment of the partition coefficient was made based on the KowWin calculation method (Epiwin v3.10, Copyright©, 1990-2000, Microsoft Corp William Meylan) using the structure of the test material.

Approximate Pow : 5.62x10⁵

Log₁₀ P_ow estimate: 5.75

Definitive test

Calibration

The retention times, capacity factors (k) and log10 Pow values for the reference standards are shown in the table below:

	RT1 (min)	RT2 (min)	RT3 (min)	RT4 (min)	RT5 (min)	mean RT (min)	STD	CV %	K	log K	log Pow
T0 (Dead time)	3.62	3.62	3.62	3.60	3.62	3.62	0.01	0.25%	0.00	-	-
Isopropylbenzene	9.31	9.30	9.30	9.29	9.30	9.30	0.01	0.08%	1.57	0.196	3.70
Biphenyl	9.97	9.97	9.97	9.96	9.98	9.97	0.01	0.07%	1.76	0.245	4.00
n-Buthylbenzene	12.33	12.33	12.32	12.31	12.33	12.32	0.01	0.07%	2.41	0.382	4.50
2,6-diphenylpyridine	13.30	13.31	13.30	13.28	13.31	13.30	0.01	0.09%	2.68	0.428	4.90
Triphenylamine	18.08	18.08	18.08	18.06	18.10	18.08	0.01	0.08%	4.00	0.602	5.70
DDT	19.79	19.81	19.79	19.79	19.81	19.80	0.01	0.06%	4.48	0.651	6.50

RT = Retention time

Mean RT = Mean retention time

STD = standard deviation

CV = coefficient of variation

Correlation (r) = 0.9831

Slope = 5.6707

Intercept = 2.5171

Partition coefficient of sample

The retention times, capacity factors (k) and log10 Pow values determined for the sample are shown below:

	RT1 (min)	RT2 (min)	RT3 (min)	RT4 (min)	RT5 (min)	mean RT (min)	STD	CV %	K	log K	log Pow
T0 (Dead time)	3.62	3.60	3.62	3.62	3.60	3.61	0.01	0.30%	0.000		-
Sample	20.52	20.50	20.48	20.54	20.52	20.51	0.02	0.11%	4.679	0.670	6.32

The partition coefficient was calculated using the following equation:

Log₁₀ Pow = slope x Log₁₀ K + intercept

Mean log₁₀ Pow : 6.32

Partition coefficient: 2.09x10⁶

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, between logKow 3.7 and 6.5, and the result for the sample was interpolated from the linear regression.

The partition coefficient (log Kow) of the test substance has been determined to be 6.16 (at 30°C and pH6).

Description of key information

Potential for bioaccumulation, according to CLP classification criteria for aquatic chronic toxicity (log Kow >4).

Key value for chemical safety assessment

Log Kow (Log Pow):

5.52

at the temperature of:

25 °C

Additional information

Two fully reliable studies, conducted according to recognized OECD/EC methods and under GLP, are available. Both could be considered as a key studies, however the first one (Firmenich 2010) was performed with the HPLC method, based on comparative elution versus standards, and the second one (Fraunhofer 2013) was performed with the slow-stirring method, which is considered more accurate as based on actual phase partitioning and analysis. Therefore the slow-stirring result is prefered and retained as key data, rather than the mean value.