trans-2-(4-Bromo-3-fluorophenyl)-5-butyl-[1,3]dioxane

Water solubility

Link to relevant study record(s)

Reference

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

from 2018-09-27 to 2019-01-28

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method A.6 (Water Solubility)

Deviations:

no

GLP compliance:

no

Type of method:

column elution method

Key result

Water solubility:

1.04 mg/L

Conc. based on:

test mat.

Temp.:

20 °C

pH:

>= 5.7 - <= 6.2

Preliminary Visual Estimation of the Water Solubility

Table 1. Appearance of the test mixtures

Amount of the test item in mg	Total volume in mL	Appearance of mixture
12.2	100	not dissolved
10.0	500	not dissolved
3.7	500	not dissolved

The solubility of the test item in water is below 10 mg/L. Therefore, the water solubility had to be determined by the "column elution method".

 

Column elution method

Individual conditions

Column 1:

Rotation period of the fraction accumulator:     90 min per fraction

Flow rate:                                                                 approx. 12.5 mL/h

Duration of sampling:                                            about 70 h (47 fractions)

Table 2. Column-elution method: Column 1

Fraction No.	V in mL	pH	Water Solubility in µg/L
37	19.5	6.0	1047
38	19.5	6.2	1025
39	19.5	5.8	1041
40	19.5	5.7	921
41	19.5	5.8	1012

Result column 1: The water solubility was found to be 1009 µg/L.

 

Column 2:

Rotation period of the fraction accumulator:     45 min per fraction

Flow rate:                                                                 approx. 25.0 mL/h

Duration of sampling:                                            about 70 h (94 fractions)

Table 3. Column-elution method: Column 2

Fraction No.	V in mL	pH	Water Solubility in µg/L
80	16.0	6.1	1062
81	16.0	5.8	1122
82	16.0	6.1	1016
83	16.0	5.9	1082
84	16.0	5.8	1029

Result column 2: The water solubility was found to be 1062 µg/L.

Coating check:

Table 4. Coating check

	Amount of test item used for coating / mg	Measured concentration of test item in eluate / mg/L	Amount of test item eluted / mg
Column 12.5 mL/h	26.4	1.042 / 1.040	20.8
Column 25.0 mL/h		1.008 / 1.011	20.2

The coating check was successful. Enough test item remained on the columns.

The water solubility of the test item was determined to be 1036 µg/L (1.04 mg/L).

Conclusions:

The water solubility of the test item at a temperature of 20 °C was determined to be cs = 1.04 mg/L.

Executive summary:

The water solubility of the test item was determined according to OECD 105 and Regulation (EC) No. 440/2008 method A.6 using the column elution method with HPLC analysis. About 105.4 mg test item were weighed and dissolved in 100 mL acetone. 25 mL of this solution were added to about 3 g sea sand and the mixture was shaken. The solvent was then removed under reduced pressure using a rotary evaporator (40 °C, approx. 40 mbar). The dry residues were placed into the columns of the test apparatus, which were afterwards filled with water (test temperature: 20 °C, water pH at 23 °C: 5.6). After a swelling time of 2 h the pump was started to rinse the substance coated sand with distilled water. Two identical columns were prepared - one of them was exposed to a flow rate of about 12.5 mL/h (column 1), the other one to 25.0 mL/h (column 2). The concentration of test item was determined by means of HPLC. The pH of each sample was recorded. The water solubility of the test item was determined to be 1.04 mg/L at 20 °C (pH = 5.7 – 6.2).

Description of key information

The water solubility of the test item at a temperature of 20 °C was determined to be cs = 1.04 mg/L.

Key value for chemical safety assessment

Water solubility:

1.04 mg/L

at the temperature of:

20 °C

Additional information

The water solubility of the test item was determined according to OECD 105 and Regulation (EC) No. 440/2008 method A.6 using the column elution method with HPLC analysis (reference 4.8-1). About 105.4 mg test item were weighed and dissolved in 100 mL acetone. 25 mL of this solution were added to about 3 g sea sand and the mixture was shaken. The solvent was then removed under reduced pressure using a rotary evaporator (40 °C, approx. 40 mbar). The dry residues were placed into the columns of the test apparatus, which were afterwards filled with water (test temperature: 20 °C, water pH at 23 °C: 5.6). After a swelling time of 2 h the pump was started to rinse the substance coated sand with distilled water. Two identical columns were prepared - one of them was exposed to a flow rate of about 12.5 mL/h (column 1), the other one to 25.0 mL/h (column 2). The concentration of test item was determined by means of HPLC. The pH of each sample was recorded. The water solubility of the test item was determined to be 1.04 mg/L at 20 °C (pH = 5.7 – 6.2).