Fluocortolone

Water solubility

Link to relevant study record(s)

Reference

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

21 Jan - 27 Jan 1999

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study without detailed documentation

Qualifier:

according to guideline

Guideline:

EU Method A.6 (Water Solubility)

Deviations:

no

GLP compliance:

not specified

Type of method:

flask method

Key result

Water solubility:

204 mg/L

Conc. based on:

test mat.

Loading of aqueous phase:

20 other: mg/5 mL

Incubation duration:

12 d

Temp.:

20 °C

pH:

5.2

Remarks on result:

other: 95 % confidence interval (0.203–0.205 g/L)

Water solubility:

>= 235.5 - <= 236.6 mg/L

Conc. based on:

test mat.

Loading of aqueous phase:

20 other: mg/5 mL

Incubation duration:

1 d

Temp.:

20 °C

pH:

ca. 5

Water solubility:

>= 203.9 - <= 204.3 mg/L

Conc. based on:

test mat.

Loading of aqueous phase:

20 other: mg/5 mL

Incubation duration:

5 d

Temp.:

20 °C

pH:

ca. 5

Water solubility:

>= 203.3 - <= 206.5 mg/L

Conc. based on:

test mat.

Loading of aqueous phase:

20 other: mg/5 mL

Incubation duration:

7 d

Temp.:

20 °C

pH:

ca. 5

Details on results:

The mean value for the water solubility was calculated from the results of the sampling times t = 5, 7 and 12 days. The pH value of the test solutions was measured at t = 12 days to be 5.20 (mean value of 3 measurements).

According to X-ray powder diffraction the starting material consisted of polymorph II and the insoluble residues from water consisted of the monohydrate.

 

Validity criteria for the measurement of the water solubility:

Target condition according to guideline EU Method A.6:	Actual condition according to the study:	Validity criteria met:
The test is preferably run at 20 ± 0.5 °C or 30 ± 0.5 °C if preliminary test is used.	the flask had been put into a water bath maintained at 30 °C + 0.5 °.	Yes
A substance-specific analytical method is preferred for these determinations, since small amounts of soluble impurities can cause large errors in the measured solubility. Examples of such methods are: gas or liquid chromatography, titration methods, photometric methods, voltametric methods.	HPLC was used for analytical measurements.	Yes
The pH of each sample should be recorded.	The pH for each sample is reported (mean of three measurements).	Yes

 

Conclusions:

The water solubility of 204 mg/L was measured at 20 °C (95 % confidence interval: 0.203-0.205 g/L). The mean pH value of the saturated water solutions was determined to be 5.2.

Executive summary:

According to the flask method the water solubility of 204 mg/L was measured at 20 °C (95 % confidence interval: 0.203 -0.205 g/L). The mean pH value of the saturated water solutions was determined to be 5.2. Fluocortolone can be considered as moderately soluble. The pH value of the saturated water solutions was determined to be 5.2.

Description of key information

The water solubility of 204 mg/L was measured at 20 °C (95 % confidence interval: 0.203 - 0.205 g/L). The mean pH value of the saturated water solutions was determined to be 5.2.

Key value for chemical safety assessment

Water solubility:

204 mg/L

at the temperature of:

20 °C

Additional information

The mean value for the water solubility was calculated from the results of the sampling times t=5, 7 and 12 days. The pH value of the test solutions was measured at t = 12 days to be 5.20 (mean value of 3 measurements). The substance can be considered to be moderately soluble in water.