Cyclopropanecarboxylic acid, 2-[1-(3,3-dimethylcyclohexyl)ethoxy]-2-methylpropyl ester

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:

02-07-2009 to 29-07-2009

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: March 2008 ; signature: June 2008

Type of method:

HPLC method

Partition coefficient type:

octanol-water

Analytical method:

high-performance liquid chromatography

Type:

log Pow

Partition coefficient:

>= 5.5 - <= 5.6

Temp.:

35 °C

pH:

7

Remarks on result:

other: range of log Pow; (n=3). Individual values were 5.5, 5.6, 5.6

HPLC method

The mean void time (t0) was determined to be 2.4 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 a regression line represented by the equations:

Calibration: log Pow = a * log k + b

where correlation coefficient r = 0.9812, a= 3.0282, b = 2.7395.

Table 2. Calibration data

Standard	Retention Time (min)			Capacity Factor (k')	log10 k'	log10 Pow
	Injection 1	Injection 2	Mean
Thiourea	2.407	2.402	2.40	-	-	-
Benzyl alcohol	2.926	2.921	2.92	0.216	-0.666	1.1
Benzene	4.196	4.189	4.19	0.744	-0.129	2.1
Toluene	5.206	5.198	5.20	1.163	0.066	2.7
Cumene	7.755	7.746	7.75	2.223	0.347	3.7
Fluoranthene	15.970	15.959	15.96	5.639	0.751	4.7
4,4'-DDT	24.980	24.945	24.96	9.382	0.972	6.2

 

Table 3. Test item determination

Peak	Injection	mean retention time (min)	Mean Capacity Factor (k')	Mean Log10 k'	Mean Log10 Pow
1	1	21.380	7.8958	0.8974	5.5
	2	21.400
2	1	23.122	8.6197	0.9355	5.6
	2	23.139
3	1	24.305	9.1148	0.9597	5.6
	2	24.337

Overall log10 Pow: ≥ 5.5 and ≤ 5.6

Conclusions:

The partition coefficient of the test item was determined to be log Pow = ≥ 5.5 and ≤ 5.6 for three constituent peaks at 35°C and ca. pH 7.00

Executive summary:

The n-octanol/water partition coefficient was determined using the HPLC method within OECD TG 117 and EU Method A.8 in accordance with GLP. The test was performed with a concentration of 25 mg test item in 50 mL methanol / 20 mM potassium phosphate butter (pH 7.0, 75/25 v/v), injected at 100 µL with a mobile phase of 75% methanol : 25% water with potassium phosphate buffer (pH 7.0). Samples of the test item were analysed via HPLC on a C18 column with refractive index detector. Calibration was performed using six reference items with known log Pow values (given by the guidelines). The dead time of the HPLC system was determined with thiourea. The dead time and the reference items were measured in duplicate. The test item was injected and measured in duplicate. Three individual partition coefficient values for each of the three chromatographic resolved test item signals were derived. A mean value was calculated from these individual log Pow values which were determined to be 5.5, 5.6 and 5.6 respectively. The partition coefficient of the test item was determined to be in the log Pow range: 5.5 to 5.6 at a mean temperature 35°C and approximately neutral pH.

Reference 2

Endpoint:

partition coefficient

Type of information:

experimental study

Remarks:

biodegradation metabolite of registered substance

Adequacy of study:

supporting study

Study period:

02-07-2009 to 29-07-2009

Reliability:

2 (reliable with restrictions)

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: March 2008 ; signature: June 2008

Type of method:

HPLC method

Partition coefficient type:

octanol-water

Analytical method:

high-performance liquid chromatography

Type:

log Pow

Partition coefficient:

>= 4 - <= 4.1

Temp.:

35 °C

pH:

7

Remarks on result:

other: range of log Pow; (n=2). Individual values were 4.0, 4.1 and 4.0, 4.1

HPLC method

The mean void time (t0) was determined to be 2.42 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 a regression line represented by the equations:

Calibration: log Pow = a * log k + b

where correlation coefficient r = 0.9897, a= 2.6992, b = 2.7168

 

Table 2. Calibration data

Substance	Retention Time Injection 1 (min)	Retention Time Injection 2 (min)	Mean (min)	Capacity Factor (k’)	log 10 k’	log 10 Pow
Thiourea	2.426	2.416	2.42	-		dead time
Benzyl alcohol	2.950	2.937	2.94	0.216	-0.66	1.1
Benzene	4.231	4.212	4.22	0.744	-0.129	2.1
Toluene	5.249	5.226	5.24	1.163	0.066	2.7
1,4-dichlorobenzene	6.495	6.468	6.48	1.677	0.225	3.4
Cumene	7.815	7.784	7.80	2.222	0.347	3.7
1,2,4-trichlorobenzene	9.864	9.644	9.66	2.992	0.476	4.2
Fluoranthene	16.052	15.990	16.02	5.618	0.750	4.7

 

Table 3. Test item determination

Peak	Injection	mean retention time (min)	Mean Capacity Factor (k')	Mean Log10 k'	Mean Log10 Pow
1	1	9.64	2.9810	0.477	4.0
	2	9.64
2	1	10.53	3.3503	0.5251	4.1
	2	10.53

Overall log10 Pow: ≥ 4.0 and ≤ 4.1

Conclusions:

The partition coefficient of the test item was determined to be log Pow = ≥ 4.0 and ≤ 4.1 for two constituent peaks at 35°C and ca. pH 7.00

Executive summary:

The n-octanol/water partition coefficient was determined using the HPLC method within OECD TG 117 and EU Method A.8 in accordance with GLP. The test was performed with a concentration of 25 .1mg test item in 50 mL methanol / 20 mM potassium phosphate butter (pH 7.0, 75/25 v/v), injected at 100 µL with a mobile phase of 75% methanol : 25% with potassium phosphate buffer (pH 7.0). Samples of the test item were analysed via HPLC on a C18 column with refractive index detector. Calibration was performed using seven reference items with known log Pow values (given by the guidelines). The dead time of the HPLC system was determined with thiourea. The dead time and the reference items were measured in duplicate. The test item was injected and measured in duplicate. Three individual partition coefficient values for each of the two chromatographic resolved test item signals were derived. A mean value was calculated from these individual log Pow values which were determined to be 4.0 and 4.1 respectively. The partition coefficient of the test item was determined to be in the log Pow range: 4.0 and 4.1 at a mean temperature 35°C and approximately neutral pH.

Reference 3

Endpoint:

partition coefficient

Type of information:

experimental study

Remarks:

biodegradation metabolite of registered substance

Adequacy of study:

supporting study

Study period:

21-09-2009 to 06-10-2009

Reliability:

2 (reliable with restrictions)

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: March 2008 ; signature: June 2008

Type of method:

HPLC method

Partition coefficient type:

octanol-water

Analytical method:

high-performance liquid chromatography

Type:

log Pow

Partition coefficient:

ca. 1.9

Temp.:

35 °C

pH:

7

HPLC method

The mean void time (t0) was determined to be 2.42 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 a regression line represented by the equations:

Calibration: log Pow = a * log k + b

where correlation coefficient r = 0.9930, a= 2.1985, b = 1.7920

 

Table 2. Calibration data

Substance	Retention Time Injection 1 (min)	Retention Time Injection 2 (min)	Mean (min)	Capacity Factor (k’)	log 10 k’	log 10 Pow
Thiourea	2.339	2.339	2.34	-		dead time
Benzyl alcohol	3.314	3.304	3.31	0.416	-0.3.81	1.1
Benzene	6.199	6.176	6.19	1.648	0.217	2.1
Toluene	9.312	9.277	9.29	2.977	0.474	2.7
1,4-dichlorobenzene	14.599	14.541	14.57	5.234	0.719	3.4
Cumene	19.950	19.871	19.91	7.520	0.876	3.7
1,2,4-trichlorobenzene	27.338	27.218	27.28	10.672	1.028	4.2

 

Table 3. Test item determination

Peak	Injection	mean retention time (min)	Mean Capacity Factor (k')	Mean Log10 k'	Mean Log10 Pow
1	1	4.93	1.1095	0.0451	1.9
	2	4.93

Overall log10 Pow: 1.9

Conclusions:

The partition coefficient of the test item was determined to be log Pow = 1.9 at 35°C and ca. pH 7.00

Executive summary:

The n-octanol/water partition coefficient was determined using the HPLC method within OECD TG 117 and EU Method A.8 in accordance with GLP. The test was performed with a concentration of 25 .1mg test item in 50 mL methanol / 20 mM potassium phosphate butter (pH 7.0, 60/40 v/v), injected at 100 µL with a mobile phase of 60% methanol : 40% water with potassium phosphate buffer (pH 7.0). Samples of the test item were analysed via HPLC on a C18 column with refractive index detector. Calibration was performed using six reference items with known log Pow values (given by the guidelines). The dead time of the HPLC system was determined with thiourea. The dead time and the reference items were measured in duplicate. The test item was injected and measured in duplicate. An individual partition coefficient value for each of the chromatographic resolved test item signals was derived. A mean value was calculated from the individual log Pow values which were determined to be 1.9. The partition coefficient of the test item was determined to be log Pow 1.9 at a mean temperature 35°C and approximately neutral pH.

Description of key information

1. log Pow = ≥ 5.5 and ≤ 5.6 at 35 °C and pH 7.00, OECD TG 117 - HPLC Method, 2009

2. Supporting information on (bio)degradation metabolite : (2-(1-(3,3-dimethylcyclohexyl)ethoxy)-2-methylpropan-1-ol (isomers thereof)) : log Pow = ≥ 4.0 and ≤ 4.1 at 35 °C and pH 7.00, OECD TG 117 - HPLC Method, 2009

3. Supporting information on (bio)degradation metabolite : (2-(1-(3,3-dimethylcyclohexyl)ethoxy)-2-methylpropanoic acid ) : log Pow = 1.90 at 35 °C and pH 7.00, OECD TG 117 - HPLC Method, 2009

Key value for chemical safety assessment

Log Kow (Log Pow):

5.6

Additional information

Key study : OECD TG 117, 2009 : The n-octanol/water partition coefficient was determined using the HPLC method within OECD TG 117 and EU Method A.8 in accordance with GLP. The test was performed with a concentration of 25 mg test item in 50 mL methanol / 20 mM potassium phosphate butter (pH 7.0, 75/25 v/v), injected at 100 µL with a mobile phase of 75% methanol : 25% water with potassium phosphate buffer (pH 7.0). Samples of the test item were analysed via HPLC on a C18 column with refractive index detector. Calibration was performed using six reference items with known log Pow values (given by the guidelines). The dead time of the HPLC system was determined with thiourea. The dead time and the reference items were measured in duplicate. The test item was injected and measured in duplicate. Three individual partition coefficient values for each of the three chromatographic resolved test item signals were derived. A mean value was calculated from these individual log Pow values which were determined to be 5.5, 5.6 and 5.6 respectively. The partition coefficient of the test item was determined to be in the log Pow range: 5.5 to 5.6 at a mean temperature 35°C and approximately neutral pH.

The determination was performed at 35°C (column temperature), however the values can be considered to represent the values at an unspecified, probably ambient temperature since no mention is made in the guidelines of the temperature at which the tabulated reference substances log Kow values were determined. Partition coefficients of the test and reference substances are assumed to vary with temperature in the same way.

 

Supporting information on (bio)degradation metabolite : (2-(1-(3,3-dimethylcyclohexyl)ethoxy)-2-methylpropan-1-ol), OECD TG 117, 2009a :The n-octanol/water partition coefficient was determined using the HPLC method within OECD TG 117 and EU Method A.8 in accordance with GLP. The test was performed with a concentration of 25 .1mg test item in 50 mL methanol / 20 mM potassium phosphate butter (pH 7.0, 75/25 v/v), injected at 100 µL with a mobile phase of 75% methanol : 25% with potassium phosphate buffer (pH 7.0). Samples of the test item were analysed via HPLC on a C18 column with refractive index detector. Calibration was performed using seven reference items with known log Pow values (given by the guidelines). The dead time of the HPLC system was determined with thiourea. The dead time and the reference items were measured in duplicate. The test item was injected and measured in duplicate. Three individual partition coefficient values for each of the two chromatographic resolved test item signals were derived. A mean value was calculated from these individual log Pow values which were determined to be 4.0 and 4.1 respectively. The partition coefficient of the test item was determined to be in the log Pow range: 4.0 and 4.1 at a mean temperature 35°C and approximately neutral pH.

 

Supporting information on (bio)degradation metabolite : (2-(1-(3,3-dimethylcyclohexyl)ethoxy)-2-methylpropanoic acid), OECD TG 117, 2009b : The n-octanol/water partition coefficient was determined using the HPLC method within OECD TG 117 and EU Method A.8 in accordance with GLP. The test was performed with a concentration of 25 .1mg test item in 50 mL methanol / 20 mM potassium phosphate butter (pH 7.0, 60/40 v/v), injected at 100 µL with a mobile phase of 60% methanol : 40% water with potassium phosphate buffer (pH 7.0). Samples of the test item were analysed via HPLC on a C18 column with refractive index detector. Calibration was performed using six reference items with known log Pow values (given by the guidelines). The dead time of the HPLC system was determined with thiourea. The dead time and the reference items were measured in duplicate. The test item was injected and measured in duplicate. An individual partition coefficient value for each of the chromatographic resolved test item signals was derived. A mean value was calculated from the individual log Pow values which were determined to be 1.9. The partition coefficient of the test item was determined to be log Pow 1.9 at a mean temperature 35°C and approximately neutral pH.