2-sec-butylphenol

Partition coefficient

Link to relevant study record(s)

Reference

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Study period:

29 June, 2009 - 6 August, 2009

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: The study has been performed according to OECD and/or EC guidelines, and according to GLP principles.

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)

Type of method:

HPLC method

Partition coefficient type:

octanol-water

Analytical method:

high-performance liquid chromatography

Type:

log Pow

Partition coefficient:

3

Temp.:

25 °C

pH:

ca. 7

Type:

Pow

Partition coefficient:

1 000

Temp.:

25 °C

pH:

ca. 7

Details on results:

The calculation method was used for a preliminary estimation. Calculation of the Pow: The Pow of the test substance was calculated to be 3.7 x 10E3 (log Pow 3.57) using the Rekker calculation method.

However, since the HPLC method is a more accurate method, the results of this method are reported.

In the chromatogram of the test substance solution, several peaks were observed. The large peak at about 22 minutes was considered to derive from the test substance. The peaks between 0 and 4 minutes were also observed in the chromatogram of the blank solution. Therefore, it was assumed that these peaks did not derive from the test substance.

The results of the HPLC method are given in the table 10:

Table 10: P_ow at neutral pH

Substance	Tr,1	Tr,2	Mean tr(n=2)	Log Pow	Pow
Formamide (t0)	1.125	1.125	1.125
Ethylmethylketone	1.665	1.665	1.665	0.3
Benzylalcohol	2.518	2.510	2.514	1.1
Nitrobenzene	5.643	5.587	5.615	1.9
Toluene	16.262	16.080	16.171	2.7
Bromobenzene	21.042	20.753	20.898	3.0
1,4-dichlorobenzene	35.484	35.020	35.302	3.4
Test substance	21.986	21.918	21.952	3.0	1.0 x 10^3

The equation of the regresion line of the calibration curve of the log k' of the reference substances as function of log P_ow was: log k' = 0.592 x log P_ow-0.520 (r = 0.9991, n = 12).

Conclusions:

The results of the Rekker calculation method and the HPLC method differ more than 0.3 log units. Since the HPLC method is a more accurate method, the results of this method are reported.

The Pow and log Pow values of 2-sec-butylphenol at 25°C are 1.0x10E3 and 3.0, respectively.

Executive summary:

The partition coefficient of the substance 2 -sec-butylphenol was determined using the Rekker calculation method and the HPLC method. The results of the Rekker calculation method and the HPLC method differ more than 0.3 log units. Since the HPLC method is a more accurate method, the results of this method are reported. The method followed OECD Guideline 117 (Partition Coefficient (n-octanol / water), HPLC Method) and EU Method A.8 (Partition Coefficient) In the chromatogram of the test substance solution, several peaks were observed. The large peak at about 22 minutes was considered to derive from the test substance. The peaks between 0 and 4 minutes were also observed in the chromatogram of the blank solution. Therefore, it was assumed that these peaks did not derive from the test substance. The equation of the regresion line of the calibration curve of the log k' of the reference substances as function of log P_owwas: log k' = 0.592 x log P_ow-0.520 (r = 0.9991, n = 12).

The P_ow and log P_ow values of 2-sec-butylphenol at 25°C are 1.0x10³ and 3.0, respectively.

Description of key information

Pow = 1000 at 25°C, pH ca. 7
log Pow = 3 at 25°C, pH ca. 7

Key value for chemical safety assessment

Log Kow (Log Pow):

3

at the temperature of:

20 °C

Additional information

The partition coefficient of the substance 2 -sec-butylphenol was determined using the Rekker calculation method and the HPLC method. The results of the Rekker calculation method and the HPLC method differ more than 0.3 log units. Since the HPLC method is a more accurate method, the results of this method are reported. The method followed OECD Guideline 117 (Partition Coefficient (n-octanol / water), HPLC Method) and EU Method A.8 (Partition Coefficient) In the chromatogram of the test substance solution, several peaks were observed. The large peak at about 22 minutes was considered to derive from the test substance. The peaks between 0 and 4 minutes were also observed in the chromatogram of the blank solution. Therefore, it was assumed that these peaks did not derive from the test substance. The equation of the regresion line of the calibration curve of the log k' of the reference substances as function of log P_owwas: log k' = 0.592 x log P_ow-0.520 (r = 0.9991, n = 12).

The P_owand log P_owvalues of 2-sec-butylphenol at 25 °C are 1.0x10³and 3.0, respectively.