4-methylcyclohexanone

Water solubility

Link to relevant study record(s)

Reference

Endpoint:

water solubility

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 105 (Water Solubility)

Version / remarks:

adopted July 27, 1995

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method A.6 (Water Solubility)

Version / remarks:

30 May 2008

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

flask method

Key result

Water solubility:

23.2 g/L

Conc. based on:

test mat.

Temp.:

20 °C

pH:

4.7

Remarks on result:

other: Water solubility range: 23.1 to 23.3 g/L

Preliminary test: The preliminary estimate of water solubility was 23.9 g/L.

Definitive test: The mean peak areas obtained for the standard and sample solutions are shown in Table 2. The water solubility determined for each sample is shown in Table 3.

Overall mean water solubility: 23.2 g/L

Water solubility range: 23.1 to 23.3 g/L

Relative standard deviation: 0.56 %

Test temperature: 20.0 ± 0.5°C

Validation

The linearity of the detector response with respect to concentration was assessed over the nominal concentration range of 100 to 1000 mg/L (equivalent to 5.0 to 50 g/L for the sample solutions, correcting for dilution factor). On plotting the data the linearity was satisfactory with a first order correlation coefficient of 1.000 being obtained. The equation of the correlation was as follows:

y = 8.586 x 1.209 x 10⁴

where: y = peak area, x = concentration (mg/L)

To confirm specificity of the analytical method, aliquots of a standard solution and a sample solution were analysed using a gas chromatography mass spectroscopy (GC-MS) technique to record the mass spectra of the analyte peak used for quantification. The peak spectra generated were consistent both with the proposed structure for the test item and also between the standard and sample solutions. The mass of m/z = 112 is the parent test item, the mass of m/z = 97 is the parent with the loss of the methyl group and the mass of m/z = 55 is characteristic of cyclic, saturated ketones. The minor shift in retention time between the GC-FID and GC-MS methodologies can be attributed to the influence of the vacuum associated with the mass selective detector accelerating the flow through the column. The precision of the determination can be addressed from the standard deviation for the mean concentration from the three individual samples on analysis. A relative standard deviation value of 5.56 % was obtained. The results satisfied the guideline quality criteria of less than 15 % variance and in addition, no time dependent trend to the data was evident. In the absence of any necessary extraction techniques, no determination of accuracy was considered relevant to the analytical procedure.

Discussion

On completion of the re-equilibration period at 20 °C, the samples remained saturated, with excess, undissolved test item present. Following centrifugation, the isolated sample solutions were free from any undissolved test item prior to analysis.

Conclusions:

Interpretation of results (migrated information): slightly soluble (0.1-100 mg/L)
In a valid, reliable and conclusive study according to OECD TG 105, the water solubility of the test substance was 23.2 g/L at 20 °C ± 0.5 °C.

Executive summary:

The water solubility of the test item was determined according to OECD TG 105 to be 23.2 g/L at a temperature of 20.0 ± 0.5 °C.

Description of key information

Two studies for the water solubility of 4 -methylcyclohexanone are available:

23.2g/L at 20°C, OECD TG 105, O'Connor 2016

24.3g/L at 20°C, no guideline, Stephenson 1992

The results for both studies are in good agreement. The most recent study conducted under GLP (O'Connor 2016) was selected as the key study, and is carried forward for risk assessment purposes.

Key value for chemical safety assessment

Water solubility:

23.2 g/L

at the temperature of:

20 °C