2,2'-methylenebis[6-(1-methylcyclohexyl)-p-cresol]

Surface tension

Administrative data

Endpoint:

surface tension

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

the study does not need to be conducted because water solubility is below 1 mg/L at 20°C

Justification for type of information:

The water solubility of the test substance is < 3 μg/l (see Project 508847). According to the guidelines, substances with a water solubility < 1 mg/l need not to be tested. The test on the surface tension of the test substance was therefore not required.

Cross-reference

Reason / purpose for cross-reference:

data waiving: supporting information

Reference

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

23 June 2015 to 10 September 2015

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Reason / purpose for cross-reference:

reference to same study

Reason / purpose for cross-reference:

reference to same study

Reason / purpose for cross-reference:

reference to same study

Reason / purpose for cross-reference:

reference to same study

Reason / purpose for cross-reference:

reference to same study

Reason / purpose for cross-reference:

data waiving: supporting information

Reason / purpose for cross-reference:

reference to same study

Reason / purpose for cross-reference:

reference to same study

Qualifier:

according to guideline

Guideline:

EU Method A.6 (Water Solubility)

Version / remarks:

European Community (EC), EC no. 440/2008, Part A: Methods for the Determination of Physico-Chemical Properties, Guideline A.6: “Water Solubility”, Official Journal of the European Union no. L142, May 31, 2008.

Deviations:

no

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

Version / remarks:

Organization for Economic Co-operation and Development (OECD), OECD Guidelines for the Testing of Chemicals no. 105: "Water Solubility", July 27, 1995.

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPPTS 830.7840 (Water Solubility)

Version / remarks:

United States Environmental Protection Agency (EPA), Product Properties Test Guidelines no. OPPTS 830.7840: "Water Solubility: Column Elution Method; Shake Flask Method", March 1998.

Deviations:

no

GLP compliance:

yes

Type of method:

column elution method

Specific details on test material used for the study:

Identification: 2,2'-methylenebis[6-(1-methylcyclohexyl)-p-cresol]
Appearance: White to cream powder
Batch: WWP4J0001
Purity/Composition: 92.2%
Test substance storage: At room temperature
Stable under storage conditions until: 03 September 2018 (retest date)
Purity/composition correction factor: Yes, correction factor is according to purity
Test substance handling: No specific handling conditions required

Water solubility:

<= 3 µg/L

Conc. based on:

test mat.

Temp.:

20 °C

pH:

> 7.3 - < 7.4

Details on results:

Preliminary test
Though water solubility of the test substance could not be determined accurately due to technical problems, it could be safely concluded that water solubility was <10-2 g/l. Based on this, it was decided to use the column elution method during the main study.

Main study
The turbidity of the eluates was < 0.2 NTU demonstrating the absence of undissolved particles in the eluates.
The coefficient of variation of the column filled with carrier material containing the test substance did not meet the requirement of ≤ 30% (i.e. 51 and 65%). This is in agreement with the results obtained during method validation in which a higher coefficient of variation at LOQ level (i.e. 8.4%). Was obtained even after discarding one outlier.
Similar concentrations were measured in the samples from the blank column. Concentration corrected for purity in the samples from the blank column eluted at 24 ml/hour ranged from 0.4 to 3.6 μg/l and from the blank column eluted at 12 ml/hour from not detected to 2.3 μg/l excluding two samples at 11 and 46 μg/l. Because of this spread, it is not possible to correct water solubility of the test substance for the blank.
It was therefore decided to report water solubility of the test substance corrected for purity as ≤ 3 μg/l i.e. the highest concentration measured excluding outliers. Improvement of the method is not considered possible.

Main study – water solubility of the test substance

Flow rate [ml/h]	Sample no.	Concentration analysed corrected for purity			pH
		Individual [μg/l]	Mean^1 [μg/l]	CV [%]
24	1 2 3 4 5 6 7 8 9 10	13.5^3 2.98 1.27 1.29 0.93^4 0.78^4 1.80 2.70 1.17 1.04	1.55	51	7.3
12	1 2 3 4 5 6 7 8 9 10	21.4^3 2.19 1.48 0.82^4 0.80^4 0.82^4 0.75^4 0.69^4 0.95^4 3.14	1.29	65	7.4

¹Mean of the concentrations obtained at one flow rate.

²Mean of the concentrations obtained at both floe rates.

³Outlier according to Dixons Q-test at 90% confidence level. Not used for further calculations.

⁴Obtained by extrapolation of the calibration curve.

Conclusions:

The water solubility of the test substance corrected for purity at 20°C was determined to be ≤ 3e-6 g/l.

Executive summary:

The aim of the study was to determine the physico-chemical properties for 2,2'-methylenebis[6-(1-methylcyclohexyl)-p-cresol].

 

The study was based on the following guidelines:

European Community (EC), EC no. 440/2008, Part A: Methods for the Determination of Physico-Chemical Properties, Guideline A.6: “Water Solubility”, Official Journal of the European Union no. L142, May 31, 2008.

Organization for Economic Co-operation and Development (OECD), OECD Guidelines for the Testing of Chemicals no. 105: "Water Solubility", July 27, 1995.

United States Environmental Protection Agency (EPA), Product Properties Test Guidelines no. OPPTS 830.7840: "Water Solubility: Column Elution Method; Shake Flask Method", March 1998.

 

The column elution method was applied for the determination of the water solubility of 2,2'-methylenebis[6-(1-methylcyclohexyl)-p-cresol].

 

The coefficient of variation of the column filled with carrier material containing the test substance did not meet the requirement of ≤ 30% (i.e. 51 and 65%). This is in agreement with the results obtained during method validation in which a higher coefficient of variation at LOQ level (i.e. 8.4%). Was obtained even after discarding one outlier.

Similar concentrations were measured in the samples from the blank column. Concentration corrected for purity in the samples from the blank column eluted at 24 ml/hour ranged from 0.4 to 3.6 μg/l and from the blank column eluted at 12 ml/hour from not detected to 2.3 μg/l excluding two samples at 11 and 46 μg/l. Because of this spread, it is not possible to correct water solubility of the test substance for the blank.

It was therefore decided to report water solubility of the test substance corrected for purity as ≤ 3 μg/l i.e. the highest concentration measured excluding outliers. Improvement of the method is not considered possible.

 

The water solubility of the test substance corrected for purity at 20°C was determined to be ≤ 3 x 10^-6g/l.

The pH of the aqueous samples was 7.3 – 7.4.