Phenyl 4-hydroxybenzoate

Water solubility

Link to relevant study record(s)

Reference

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2018-03-06 to 2018-12-20

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

GLP compliance:

yes (incl. QA statement)

Type of method:

column elution method

Specific details on test material used for the study:

CAS No.: 17696-62-7
Batch: 018964K19K
Expiry date: 02 August 2018
Purity: 99.1%
Appearance: White powder
Storage: Room temperature

Key result

Water solubility:

< 0.05 mg/L

Conc. based on:

test mat. (dissolved fraction)

Temp.:

20 °C

pH:

ca. 6.5

Remarks on result:

other: LOQ of analytical method: 0.05 mg/L

Preliminary test:

Tables 1 and 2 summarize the results of the preliminary test (test temperature 21.0 °C).

Table 1: Results of preliminar test (1 part)

Amount of test item / g	0.10
Amount of water / mL	0.1	0.5	1	2	10	100
Approx. solubility / g/L	> 1,000	1,000 to 200	200 to 100	10 to 50	50 to 10	10 to 1
Results	Not soluble	Not soluble	Not soluble	Not soluble	Not soluble	Not soluble

Table 2: Results of preliminary test (part 2)

Amount of test item / g	0.01	0.005
Amount of water / mL	100	5,000
Approx. solubility / g/L	1 to 0.1	0.1 to 0.001
Result	Not soluble	Not soluble

Taking the visual observations into account, the preliminary test shows that the solubility of the test item was lower than 0.001 g/L. Thus the column elution method was selected for the main test.

Validation criteria:

In accordance with results from the analytical method validation, all acceptance criteria were satisfied. The applied method is consistent with the requirements of the validation for the quantitative analysis of the test item in the solutions.

Main test: Column elution method:

The results of the hydrosolubility determination are indicated in Table 3 and Table 4.

Table 3: Results of the main test (flow rate 25 mL/h)

Sample	Final results (mg/L)	pH
1 (T: 30 minutes)	< 0.05	Between 6 and 7
2 (T: 1h02min)	< 0.05	Between 6 and 7
3 (T:1h36min)	< 0.05	Between 6 and 7
4 (T: 2h10min)	< 0.05	Between 6 and 7
5 (T: 2h44min)	< 0.05	Between 6 and 7
6 (T: 3h17min)	< 0.05	Between 6 and 7
Average (mg/L)	< 0.05
Standard deviation (mg/L)	/
Relative standard deviation of repeatability	/

Table 4: Results of the main test (flow rate 12.5 mL/h)

Sample	Final results (mg/L)	pH
1 (T: 30 minutes)	< 0.05	Between 6 and 7
2 (T: 1h01min)	< 0.05	Between 6 and 7
3 (T:1h34min)	< 0.05	Between 6 and 7
4 (T: 2h06min)	< 0.05	Between 6 and 7
5 (T: 2h38min)	< 0.05	Between 6 and 7
6 (T: 3h10min)	< 0.05	Between 6 and 7
Average (mg/L)	< 0.05
Standard deviation (mg/L)	/
Relative standard deviation of repeatability	/

The analysis of the test item obtained at elution flow rates of 12.5 and 25 mL/h indicated a solubility in water which is lower than 0.05 mg/L (< LOQ).

Conclusions:

The water solubility of the test item was lower than 0.05 mg/L (< LOQ) at 20 °C and a pH of approx. 6.5.

Executive summary:

The water solubility of the test item was determined according to OECD test guideline 105 using the column elution method. The water solubility of the test item was lower than 0.05 mg/L (< LOQ) at 20 °C and a pH of approx. 6.5.

Description of key information

The water solubility of the test item was determined according to OECD test guideline 105 using the column elution method. The water solubility of the test item was lower than 0.05 mg/L (< LOQ) at 20 °C and a pH of approx. 6.5.