4-(1,1-dimethylethyl)cyclohexyl methacrylate

Water solubility

Link to relevant study record(s)

Reference

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Experimental starting date: 03 January 2017 Experimental completion date: 23 March 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method A.6 (Water Solubility)

Deviations:

no

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

flask method

Specific details on test material used for the study:

Identification: 4-tert-butylcyclohexyl methacrylate
(CAS 46729-07-1)
Appearance/physical state: clear colourless liquid (on melting)
Batch: DAR-16030
Purity: 89.2%
Expiry / retest date: 01 August 2018
Storage conditions: approximately 4 °C, in the dark

Key result

Water solubility:

0 g/L

Conc. based on:

test mat.

Incubation duration:

>= 23.75 - <= 144 h

Temp.:

20 °C

pH:

>= 6.4 - <= 6.8

Preliminary Test

The preliminary estimate of water solubility was 1.3 x 10^-4 g/L at 20 °C.

Main Test

The mean total peak areas relating to the standard and sample solutions are shown in the following table:

Solution	Mean total peakarea
Standard solution 0.163 mg/L	3.1569 x 10^5
Standard solution 0.113 mg/L	1.9992 x 10^5
Matrix blank	none detected
Sample number 1	3.0686 x 10^4
Sample number 2	3.6655 x 10^4
Sample number 3	4.6338 x 10^4
Standard solution 0.125 mg/L	2.2996 x 10^5
Standard solution 0.151 mg/L	2.6720 x 10^5
Matrix blank	none detected
Sample number 4, replicate dilution A	3.6934 x 10^4
Sample number 4, replicate dilution B	3.6490 x 10^4
Sample number 5, replicate dilution A	4.4513 x 10^4
Sample number 5, replicate dilution B	3.6580 x 10^4
Sample number 6, replicate dilution A	2.7828 x 10^4
Sample number 6, replicate dilution B	2.8325 x 10^4

        

The concentration (g/L) of test item in the sample solutions is shown in the following table:

Sample number	Time shaken at  30 ºC (hours)	Time equilibrated at 20 ºC (hours)	Concentration (g/L)	Solution pH
1	23¾	24	3.3 x 10^-5	6.7
2	48¼	24	4.0 x 10^-5	6.5
3	72	24	5.0 x 10^-5	6.6
4	96	24	4.1 x 10^-5	6.7
5	120	24	4.5 x 10^-5	6.8
6	144	24	3.1 x 10^-5	6.4

Mean concentration   :          4.0 x 10^-5 g/L at 20.0 ± 0.5 ºC
Range                         :          3.1 x 10^-5 to 5.0 x 10^-5 g/L
Standard Deviation    :          7.1 x 10^-6g/L

Validation

The linearity of the detector response with respect to concentration was assessed over the nominal concentration range of 0.02 to 0.20 mg/L. The results were satisfactory with a first order correlation coefficient (r) of 0.9966 being obtained.

Discussion

On completion of the equilibration period, the sample solutions were clear and colorless with excess test item visibly present.  After centrifugation, the isolated supernatants were visually observed to be free from un-dissolved test item prior to diluting for analysis.

On analysis of samples 1 to 3 inclusive, using the standardized initial saturation periods specified in the regulatory method of up to 72 hours, a possible increasing trend in concentration versus time was observed. Therefore additional samples (sample 4 to 6 inclusive) were performed such that the initial saturation period evaluated was increased to 144 hours. This additional analysis confirmed that the initial potential trend could be attributed to random experimental variance alone and that saturation had in fact been achieved. The concentration of all samples prepared have been used in calculation of the mean

The preliminary water solubility test indicated that the column elution method should have been performed as the solubility was less than 1 x 10^-2g/L. However, due to the physical nature of the test item, it was not possible to use this method.

It was noted that individual water solubility results failed to satisfy the specified variability of ± 15% of the mean for the flask method specified in the regulatory methods. This was attributed to the extremely low solubility of the test item and was not considered to impact on the validity of the determination. The analytical data did however satisfying the variability criteria of ± 30% of the mean stated for the column elution method, which is specific to addressing lower solubility concentrations below 10 mg/L.

Conclusions:

The water solubility of the test item has been determined to be 4.0 x 10-5 g/L of solution at 20.0 ± 0.5 °C.

Executive summary:

Water Solubility. 4.0 x 10^-5g/L of solution at 20.0 ± 0.5 °C, usingaflask methoddesigned to be compatible with Method A.6 Water Solubility of Commission Regulation (EC) No 440/2008 of 30 May 2008andMethod 105 of the OECD Guidelines for Testing of Chemicals, 27 July 1995.

Description of key information

The water solubility of the test item has been determined to be 4.0 x 10-5 g/L of solution at 20.0 ± 0.5 °C.

Key value for chemical safety assessment

Water solubility:

0.04 mg/L

at the temperature of:

20 °C