3,3-bis(4-hydroxy-5-isopropyl-o-tolyl)phthalide

Water solubility

Administrative data

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2019

Report date:

2019

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

Version / remarks:

adopted 27. Jul. 1995: “Water Solubility “

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method A.6 (Water Solubility)

Version / remarks:

31 May 2008

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

column elution method

Test material

Test material information

Constituent 1

Reference substance name:

3,3-bis(4-hydroxy-5-isopropyl-o-tolyl)phthalide

EC Number:

204-729-7

EC Name:

3,3-bis(4-hydroxy-5-isopropyl-o-tolyl)phthalide

Cas Number:

125-20-2

Molecular formula:

C28H30O4

IUPAC Name:

3,3-bis(4-hydroxy-5-isopropyl-o-tolyl)phthalide

Details on test material:

- Storage conditions: Room Temperature (20 ± 5 °C)
- Expiry date: 16. Dec. 2019

Results and discussion

Water solubility

Water solubility:

2.59 µg/L

Conc. based on:

test mat.

Temp.:

20 °C

pH:

> 5.2 - < 6.4

Applicant's summary and conclusion

Conclusions:

The water solubility of the test item has been determined to be 2.59 ± 0.50 µg/L at 20 ± 0.5 °C.
The study was performed according to the OECD TG117, EU Method A.8 and EC Regulation Method A.24 without deviations and therefore considered to be of the highest quality (reliability Klimisch 1).The validity criteria are fulfilled.

Executive summary:

The water solubility of the test item has been determined in a GLP study according to OECD 105 and EU method A.6.

In a preliminary study, the solubility of the test item in water was estimated as < 10 mg/L.

The column elution method was used for the determination of the solubility of the test item in water. Quartz sand was coated with test item and filled into a stainless steel column (150*4.6 mm). A flow rate of 25.01 mL/h was set. After discarding of the first fraction (run time 180 min), fractions were collected and measured. After seven consecutive fractions, the plateau was considered as reached, because variation was less than 30 % and no upward tendency was observed. A second run with a flow rate of 12.52 mL/h and a third run with a flow rate of 6.03 mL/h was performed likewise. No differences above 30% in the concentrations of the solutions could be determined between the sample dates of the different flow rates, supporting the independency of solubility and flow rate.

At the plateau, the concentration of 3,3-bis(4-hydroxy-5-isopropyl-o-tolyl)phthalide in water had reached: 2.59 ± 0.50 µg/L at 20 ± 0.5 °C (mean value of 15 fractions)