4,8-Cyclododecadien-1-one

Partition coefficient

Link to relevant study record(s)

Reference

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Study period:

03-12-2014 to 17-12-2014

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline study performed under GLP. All relevant validity criteria were met.

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

GLP compliance:

yes (incl. QA statement)

Remarks:

inspected: June 2013; signature: November 2013

Type of method:

HPLC method

Partition coefficient type:

octanol-water

Analytical method:

high-performance liquid chromatography

photometric method

Type:

log Pow

Partition coefficient:

>= 3.48 - <= 3.53

Temp.:

22.8 °C

pH:

7

Remarks on result:

other: Two chromatographic peaks at the associated Partition Coefficient values

HPLC method

The mean void time (t0) was determined to be 0.511 minutes.

The results of the HPLC method are given in the Table 3. The calibration curves of the log k’ of the reference substances as function of log Pow had an regression line represented by the equations:

Calibration 1: log k’ = 1.642 × log Pow + 1.2327 (r = 0.9979, n = 6 and r2 = 0.9959).

Calibration 2: log k’ = 1.640 × log Pow + 1.2366 (r = 0.9979, n = 6 and r2 = 0.9959).

 

Table 2. Calibration data

Reference Item	Log P	1^stCalibration			2^ndCalibration
		tr1 /min	k	Log K	tr2 / min	k	Log k
Atrazine	2.6	4.067	6.959	0.843	4.061	6.947	0.842
2,3-Dichloroaniline	2.8	5.072	8.926	0.951	5.062	8.906	0.950
Diphenylamin	3.4	10.885	20.301	1.308	10.859	20.250	1.306
Phenyl benzoate	3.6	14.364	27.110	1.433	14.355	27.092	1.433
Biphenyl	4.0	27.919	53.636	1.729	27.883	53.566	1.729
1,2,4-Tricholorobenzene	4.2	31.191	60.039	1.778	31.190	60.037	1.778

tR1 Retention time 1. Injection

tR2 Retention time 2. Injection

k Capacity factor reference item

log Pow Decadic logarithm of the Partition Coefficient (n-octanol / water)

 

Table 3. Test item determination – peak 1 and peak 2

	tr / min	k	Log k	Log P
Peak 1				1^stCalibration	2^ndCalibratrion
	12.418	23.301	1.37
	12.415	23.295	1.37	3.48 ± 0.02 3.43 to 3.53 (95% CI)	3.48 ± 0.02 3.43 to 3.54 (95% CI)
Mean	12.417	23.298	1.37	3.48
Peak 2				1^stCalibration	2^ndCalibratrion
	13.273	24.975	1.40
	13.267	24.963	1.40	3.53 ± 0.02 3.48 to 3.58 (95% CI)	3.53 ± 0.02 3.48 to 3.59 (95% CI)
Mean	13.270	24.969	1.40	3.53

tR : Retention time

k : Capacity factor test item

Pow : Partition Coefficient (n-octanol / water)

CI : Confidence Interval

Conclusions:

The partition coefficient of the test substance was determined to be log Pow = 3.48 – 3.53 at 22.8 °C and ca. pH 7.0

Executive summary:

The n-octanol/water partition coefficient was determined using the HPLC method within OECD TG 117 and EU Method A.8. The test was performed with a concentration of 50 mg test item/L in 60% methanol : 40% HPLC water. Samples of the test item were analysed via HPLC on a C18 column with diode array detection. Calibration was performed using six reference items with known log POW values (given by the guidelines). The reference items were measured twice, once before and once after the measurement of the test item, for which one replicate was double injected. The void time of the HPLC system was determined with sodium nitrate. Two individual log POW values for each of the two chromatographic resolved test item signals were derived under consideration of the first and second calibration and the analytically resolved chromatographic peaks. Finally, a mean value was calculated from these individual log Pow values. The log Pow was 3.48 (peak 1) to 3.53 (peak 2) in duplicate. The partition coefficient of the test substance was determined to be log Pow = 3.48 to 3.53 at mean temperature 22.8 °C and approximately neutral pH.

Description of key information

log Pow = 3.48 to 3.53 (range of peak values) at 22.8 °C and ca. pH 7.0, OECD TG 117, 2015

Additional information

The n-octanol/water partition coefficient was determined using the HPLC method within OECD TG 117 and EU Method A.8. The test was performed with a concentration of 50 mg test item/L in 60% methanol : 40% HPLC water. Samples of the test item were analysed via HPLC on a C18 column with diode array detection. Calibration was performed using six reference items with known log POW values (given by the guidelines). The reference items were measured twice, once before and once after the measurement of the test item, for which one replicate was double injected. The void time of the HPLC system was determined with sodium nitrate. Two individual log POW values for each of the two chromatographic resolved test item signals were derived under consideration of the first and second calibration and the analytically resolved chromatographic peaks. Finally, a mean value was calculated from these individual log Pow values. The log Pow was 3.48 (peak 1) to 3.53 (peak 2) in duplicate. The partition coefficient of the test substance was determined to be log Pow = 3.48 to 3.53 at mean temperature 22.8 °C and approximately neutral pH.