Ethyl diphenylcarbamate

Partition coefficient

Link to relevant study record(s)

Reference

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Study period:

March 6, 2017 - March 15, 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 107 (Partition Coefficient (n-octanol / water), Shake Flask Method)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method A.8 (Partition Coefficient - Shake Flask Method)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

flask method

Partition coefficient type:

octanol-water

Analytical method:

high-performance liquid chromatography

Key result

Type:

log Pow

Partition coefficient:

ca. 3.33

Temp.:

20 °C

pH:

>= 6.41 - <= 6.69

The test item stock solution was prepared in water pre-saturated with 1-octanol presaturated with water. The measured Ethyl diphenylcarbamate concentration in stock solution (1 -octanol) was 5.6925 g/kg (4.6963 g/L). Density of 1-octanol (supplier data) is 0.825 g/L.

 

Determination of Ethyl diphenylcarbamate contentin water phase and 1-octanol phase.

 

Table 1: Calibration solution

Weight [mg]	Dilution [mL]	Cw [mg/mL]	Peak area		Average peak area Aw	f	Average  f
22.05	25-1-25-2-10	0,00663264	793735	794821	794278	0,00000835	0.00000828
	25-1-25-3-10	0,00994896	1211352	1210161	1210756,5	0,00000822
	25-1-25-0,1-10-2,5-5	0,00016582	26966	26930	26948	0,00000615	0.00000619
	25-1-25-0,1-10	0,00033163	53038	53336	53187	0,00000624

Table 2: Study solution

Sample	Weight of the sample [mg]	Dilution [mL]	Cp [mg/mL]	Peak area		Average peak area Ap	X [g/kg]
1/w	1004.15	5	200.83	13417	13018	13217.5	0.00041
2/w	1001.60	5	200.32	12806	12774	12790	0.00040
3/w	994.45	5	198.89	20059	20141	20100	0.00063
4/w	1006.00	5	201.2	20331	19997	20164	0.00062
5/w	1003.15	5	200.63	9946	9889	9917.5	0.00031
6/w	1004.30	5	200.86	9908	10052	9980	0.00031
stock	158.6	10-1-10	1.586	1091049	1088682	1089865.5	5.6925
1/o	79.10	10	7.910	1018915	1020093	1019504	1.0677
2/o	77.80	10	7.780	978796	978312	978554	1.0419
3/o	78.30	10	7.830	1514131	1517562	1515846.5	1.6037
4/o	82.10	10	8.210	1579298	1582390	1580844	1.5951
5/o	79.95	10	7.995	759368	757129	758248.5	0.7856
6/o	82.25	10	8.225	774006	773938	773972	0.7795

Table 3. Results of measurements at 20.0°C

Vial number	1	2	3	4	5	6
Temperature,°C	19.7		19.9		20.1
Volume of added stock solution, mL	1	1	1	1	1	1
Volume of water, mL	5	5	6.7	6.7	3.3	3.3
Volume of 1-octanol, mL	4	4	2.3	2.3	5.7	5.7
Volume 1-octanol phase/ volume of water phase	1:1		1:2		2:1
Ethyl diphenylcarbamateconcentration in water phase, g/L	0.00041	0.00040	0.00063	0.00062	0.00031		0.00031
Ethyl diphenylcarbamateconcentration in 1-octanol phase, g/kg	1.0677	1.0419	1.6037	1.5951	0.7856		0.7795
Ethyl diphenylcarbamateconcentration in 1-octanol phase, g/L	0.8809	0.8596	1.3231	1.3160	0.6481		0.6431
Mass ofEthyl diphenylcarbamatein water phase∙10^3, g	0.0021	0.0020	0.0042	0.0042	0.0010		0.0010
Mass ofEthyl diphenylcarbamatein 1-octanol phase∙10^3, g	4.4045	4.2980	4.3662	4.3428	4.3423		4.3088
Mass ofEthyl diphenylcarbamatein both phases∙10^3, g	4.4066	4.3000	4.3704	4.3470	4.3433		4.3098
Added mass ofEthyl diphenylcarbamate∙10^3, g	4.6963	4.6963	4.6963	4.6963	4.6963		4.6963

 

Table 4. Measured pH values of water phase

Vial number	1	2	3	4	5	6
pH before test	6.18	6.18	6.18	6.18	6.18	6.18
pH after test	6.69	6.66	6.41	6.42	6.60	6.63

Table 5. Calculated values of partition coefficient 1-octanol/water 

Vial number	1	2	3	4	5	6
Volume 1-octanol phase/volume of water phase	1:1		1:2		2:1
Pow= C1-octanol/Cwater	2149	2149	2100	2123	2091	2075
log Pow= log(C1-octanol/Cwater)	3.33	3.33	3.32	3.33	3.32	3.32
Average log Pow+ standard deviation	3.33 ± 0.00		3.33 ± 0.01		3.32 ± 0.00
Average log Pow+ standard deviation	3.33±0.01

Conclusions:

The calculated value of logarithm to the base 10 of the test item partition coefficient 1-octanol/water (log Pow) at 20.0 ºC and at pH ranging from 6.41 to 6.69 in water is 3.33 ± 0.01.

Executive summary:

The determination of partition coefficient 1-octanol/water was performed according to OECD 107 and EU method A.8 (flask method), following GLP. The concentrations of test item were determined in both phases by HPLC method, using a liquid chromatograph Spectra-Physics. The calculated value of logarithm to the base 10 of the test item partition coefficient 1-octanol/water (log Pow) at 20.0 ºC and at pH ranging from 6.41 to 6.69 in water is 3.33 ± 0.01.

Description of key information

Key study: OECD 107 and EU method A.8. GLP study. The calculated value of logarithm to the base 10 of the test item partition coefficient 1-octanol/water (log Pow) at 20.0 ºC and at pH ranging from 6.41 to 6.69 in water is 3.33 ± 0.01.

Key value for chemical safety assessment

Log Kow (Log Pow):

3.33

at the temperature of:

20 °C

Additional information

Key study: The determination of partition coefficient 1-octanol/water was performed according to OECD 107 and EU method A.8 (flask method), following GLP. The concentrations of test item were determined in both phases by HPLC method, using a liquid chromatograph Spectra-Physics. The calculated value of logarithm to the base 10 of the test item partition coefficient 1-octanol/water (log Pow) at 20.0 ºC and at pH ranging from 6.41 to 6.69 in water is 3.33 ± 0.01.