Ethyl octanoate

Water solubility

Link to relevant study record(s)

Reference

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2016-10-21 to 2016-10-21

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

Version / remarks:

1995

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method A.6 (Water Solubility)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

flask method

Key result

Water solubility:

35.5 mg/L

Conc. based on:

test mat.

Loading of aqueous phase:

1 g/L

Incubation duration:

72 h

Temp.:

20 °C

pH:

5.6

Remarks on result:

other: Mean of 6 measurements performed after 24h, 48h and 72h incubation

1. Preliminary test (non-GLP):

The determination solubility in double distilled water was in the range of 11.3 - 113 mg/L. For the application dose for the definitive study, 1 g/L, as ca. approximately the tenfold of the maximum solubility result, was used.

2. Method validation:

- Detection limits: LOD = 50 pg/L

- Linearity: linear response in the range of nominal 0.05 - 1.5 µg/L with r2 > 0.992

- Limit of quantification: LOQ = 7.5 mg/L

- Accuracy: mean recovery rates of 91% at 1 x LOQ and 99% at 4 x LOQ

- Precision: coefficient of determination between 5.4 and 11%

- Specificity: identity of test item signals demonstrated by automatic comparisson of sample peaks against spectra obtained from standard peaks.

- Check of Tyndall-Effect: negative in all replicates and at all time points

3. Water solubility results;

Water solubility has been measured at 20°C:

Preincubation time	Replicate No.	Test substance
		Concentration (mg/L)*	Mean
24 h	1	33.5	41.0***
	2	48.4
48h	1	35.2	37.3
	2	39.4
72h	1	35.4	33.7
	2	32.0
Mean (24-72h)			35.5
Deviation (%) (24-72h)**			10.7

* Mean value of double injection, dilution factor of 50000 and exact weights taken into account

** Calculated according to formula deviation [%]= 100x(max value-min value) / min value

*** Not taken into consideration due to instable results.

pH value: 5.6

4. Validation

The concentration measured in at least the samples with the two longest incubation times (48 and 72h) should not differ by more than 15%.

Temperatures: Temperatures should be kept constant within +- 0.5°C

Conclusions:

The test item was found to have a water solubility of 35.5 mg/L at pH 5.6 and at 20°C.

Executive summary:

The water solubility of the test substance was determined according to OECD test guideline 105 (1995) and Council Regulation (EC) No. 260/2014, Method A.6.

The solubility of the test substance was determined using the flask method at 20 +/- 0.5 °C with pre-incubation at 30 +/- 0.5°C. Measurements were performed after 24, 48 and 72h pre-incubation.

The water solubility of the test substance was determined to be 35.5 mg/L (20°C, pH 5.6).

Description of key information

For this endpoint, water solubility was determined experimentally according to OECD 105, flask method. The test item was found to have a water solubility of 35.5 mg/L at 20°C (pH 5.6)

Key value for chemical safety assessment

Water solubility:

35.5 mg/L

at the temperature of:

20 °C