Butyl carbamate

Partition coefficient

Link to relevant study record(s)

Reference

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2016

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

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

Qualifier:

according to guideline

Guideline:

EU Method A.8 (Partition Coefficient - HPLC Method)

GLP compliance:

not specified

Type of method:

HPLC method

Partition coefficient type:

octanol-water

Specific details on test material used for the study:

Batch no.: #120039110
Appearance: colorless, solid
Composition: >95% Butyl carbamate; <5% n-Butanol
Purity: 93.5% (GC-MS TIC area%)

Analytical method:

high-performance liquid chromatography

Key result

Type:

log Pow

Partition coefficient:

0.3 - <= 2.75

Temp.:

25 °C

pH:

7.15

Details on results:

The chromatogram of the test substance solution showed 6 major peaks and 1 minor peak (cfr "Any other information on results incl. tables"). With the calibration function log K versus log Pow, the corresponding log Pow values were determined. As peak 6 showed a relative area < 5 %, it was considered as minor peak. Although area is not necessarily correlated to absolute concentration when UV detection is used, it is assumed that the test substance consisted mainly of the peaks 1, 2, 3, 4, 5 and 7. Due to the fact that peak 1 laid outside the calibration range (log Pow 0.3 – 2.70) the log Pow of the compounds of the test substance were in a range between < 0.3 – 2.75 (mean). The log Pow of the last eluted compound (corresponding to peak 7) was calculated with 2.75 and lies outside the calibrated range of 0.3 – 2.70. This was stated as uncritical because the calculated log Pow lied only slightly above the calibrated range and because the retention time of this compound (6.86 min) was lower than the retention time of the reference substance with the highest log Pow toluene (7.31 min).The resulting higher log Pow was only due to measurement uncertainty.

Results (table):

Peak	Mean Area [mAU*min]1	Rel. Area [%]	Mean Retention Time [min]	log POW ± Stand. Dev
1	5.047	15.67	1.350	n.c.*
2	3.145	9.77	2.017	0.795 ± 0.000
3	2.404	7.46	2.167	0.986 ± 0.000
4	12.100	37.57	2.350	1.175 ± 0.000
5	2.006	6.23	5.592	2.514 ± 0.000
6	0.351	1.09	5.900	2.578 ± 0.000
7	7.159	22.22	6.858	2.754 ± 0.000

* Not calculable, because K is negative. Because the retention time of peak 1 is lower than the retention time of thiourea, which was used for the determination of the dead time of the method, the log Pow of this peak is stated as < 0.3 (lowest log Pow of the reference substances (2-Butanone with log Pow 0.3).

1. mAU = milli absorbance units

Conclusions:

Under the study conditions, the partition coefficient (log Pow) of the test substance was determined to be in the range <0.3 - 2.75 at 25.0°C (HPLC method).

Executive summary:

A study was conducted to determine the partition coefficient of the test substance, according to OECD guideline 117 and EU Method A.8 (HPLC method). A solution of the test substance was prepared by weighing 21 mg test substance into a 20 mL flask and filling up to 21.0 mL with the mobile phase. The measured pH of the test substance solution was 7.15 (measured with pH-Meter). This solution was also used for pre-test and for determination of the log Pow of the test substance. The chromatogram of the test substance solution showed 6 major peaks and 1 minor peak. Capacity factor K and the retention times of the peaks of the test substance were used for for calculation of log Pow. Under the study conditions, the partition coefficient (log Pow) of the test substance was determined to be in the range <0.3 - 2.75 at 25.0°C (Feierabend, 2016).

Description of key information

The partition coefficient (log Kow) was determined according to OECD guideline 117 and EU Method A.8 (HPLC method) (Feierabend, 2016).

Key value for chemical safety assessment

Log Kow (Log Pow):

2.75

at the temperature of:

25 °C

Additional information

The log Kow ranged from <0.3 - 2.75.