4-methylcyclohexanone

Partition coefficient

Link to relevant study record(s)

Reference

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2015-09-14 to 2016-01-14

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)

Version / remarks:

from May 31, 2008

GLP compliance:

yes (incl. QA statement)

Type of method:

flask method

Partition coefficient type:

octanol-water

Analytical method:

gas chromatography

Key result

Type:

log Pow

Partition coefficient:

1.33

Temp.:

20 °C

pH:

>= 6.9 - <= 7

Key result

Type:

Pow

Partition coefficient:

21.7

Temp.:

20 °C

pH:

>= 6.9 - <= 7

Details on results:

In the absence of any dissociating functional groups, no manipulation of the aqueous phase pH was required to ensure that the test item was in a neutral, unionized form. Therefore the determination was performed at an unadjusted, approximately neutral pH. In addition, in the absence of any dissociating functional groups, the test item would not demonstrate pH dependent partitioning characteristics.

Table 1 TEST FLASK PHASE RATIOS

Test	Nominal Organic/Aqueous VoluRatio	Volume of Stock Solution (mL)	Volume of n‑Octanol Saturated Water (mL)
1	2:1	52	26
2		48	24
3	1:1	33	33
4		39	39
5	1:2	26	52
6		26	52

Table 2 ORGANIC PHASE ANALYSIS MEAN PEAK AREAS

Solution	Mean Peak Area
Standard 25.4 mg/L	4.1465 x 10^5
Standard 25.7 mg/L	4.2129 x 10^5
Organic phase matrix blank	No significant response
Sample 1	3.8459 x 10^5
Sample 2	3.8687 x 10^5
Sample 3	3.7538 x 10^5
Sample 4	3.7773 x 10^5
Sample 5	3.6334 x 10^5
Sample 6	3.6230 x 10^5
Stock solution A	3.9545 x 10^5
Stock solution B	3.9345 x 10^5

Table 3 AQUEOUS PHASE ANALYSIS MEAN PEAK AREAS

Solution	Mean Peak Area
Standard 25.2 mg/L	2.5730 x 10^5
Standard 26.0 mg/L	2.6660 x 10^5
Aqueous phase matrix blank	No significant response
Sample 1	1.1065 x 10^5
Sample 2	1.0721 x 10^5
Sample 3	1.0883 x 10^5
Sample 4	1.0664 x 10^5
Sample 5	9.3114 x 10^4
Sample 6	1.2623 x 10^5

Table 4 ANALYSED CONCENTRATIONS, AQUEOUS PHASE pH AND RESULTING TEST ITEM WEIGHTS

Sample Number	Total Weight (mg)*	Organic Phase		Aqueous Phase			Mass Recovery (%)
		Analysed Concentration (mg/L)	Weight (mg)†	Analysed Concentration (mg/L)	Weight (mg)†	pH
1	25.0	470	24.4	21.6	0.562	7.0	99.7
2	23.1	472	22.7	21.0	0.503	7.0	100.3
3	15.9	458	15.1	21.3	0.702	7.0	99.6
4	18.8	461	18.0	20.8	0.813	6.9	100.1
5	12.5	444	11.5	18.2	0.946	6.9	99.7
6	12.5	442	11.5	24.7	1.28	6.9	102.1

Mean analysed stock solution concentration: 482 mg/L, pH of stock solution: 5.4

* From analysis of the stock solution

† From analysis of the respective phase

Table 5 CALCULATED INDIVIDUAL PARTITION COEFFICIENT VALUES

Sample Number	Nominal Organic/Aqueous Volume Ratio	Partition Coefficient	Log10Pow	Mean Partition Coefficient
1	2:1	21.7	1.34	22.1
2		22.5	1.35
3	1:1	21.5	1.33	21.8
4		22.1	1.34
5	1:2	24.4	1.39	21.2
6		17.9	1.25

Table 6 ORGANIC PHASE LINEARITY MEAN PEAK AREAS

Solution	Mean Peak Area
Matrix blank	No significant response
Standard 10.2 mg/L	1.7943 x 10^5
Standard 20.3 mg/L	3.3861 x 10^5
Standard 25.4 mg/L	4.1988 x 10^5
Standard 25.7 mg/L	4.2496 x 10^5
Standard 30.5 mg/L	5.0015 x 10^5
Standard 40.6 mg/L	6.7899 x 10^5

Table 7 AQUEOUS PHASE LINEARITY MEAN PEAK AREAS

Solution	Mean Peak Area
Matrix blank	No significant response
Standard 2.03 mg/L	2.3072 x 10^4
Standard 5.09 mg/L	5.4328 x 10^4
Standard 10.2 mg/L	1.0565 x 10^5
Standard 20.3 mg/L	2.0806 x 10^5
Standard 25.4 mg/L	2.5584 x 10^5
Standard 30.5 mg/L	3.1816 x 10^5

Conclusions:

In a valid, conclusive and reliable study according to OECD TG 107 (1995), the partition coefficient (n-octanol / water) of the test item was determined to be 21.7 (log10 Pow = 1.33) at a temperature of 20.0 ± 1.0 °C.

Executive summary:

During this study the partition coefficient (n-octanol / water) of the test item was determined using the flask shake method as described in OECD TG 107.

The partition coefficient (n-octanol / water) of the test item was determined to be 21.7 (log10 Pow = 1.33) at a temperature of 20.0 ± 1.0 °C.

Description of key information

A single study for the partition coefficient (n-octanol / water) was available, and determined to be 21.7 (log Pow = 1.33) at a temperature of 20.0 ± 1.0 °C.

Key value for chemical safety assessment

Log Kow (Log Pow):

1.33

at the temperature of:

20 °C