Hexamethylene diisocyanate, trimers, reaction products with 2-hydroxyethyl acrylate

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 Sep - 29 Oct 2015

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Remarks:

Water solubility was below the detecion limit of the HPLC method used. Dissolved organic carbon concentrations were measured

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

Type of method:

flask method

Specific details on test material used for the study:

Storage: room temperature, protected from direct sunlight

Water solubility:

< 0.54 mg/L

Conc. based on:

test mat. (dissolved fraction)

Temp.:

20 °C

Remarks on result:

other: water solubility of test item is below detection limit of HPLC (0.54 mg/L)

Results
No substance-specific peaks were found in the HPLC chromatograms after 1,2 and 3 days at 30 °C (followed by 24 h at 20 °C). In comparison with the blank sample, additional peaks were only seen at the dead-time of the HPLC system. These are likely to be due to either test item degradation or to very polar test item components. This could result in the overexpression of these components in the present OECD 105 test setup compared to their normal content in the test item because of their high water solubility and the very high test item loadings (1g/L in the OECD 105 test, compared to ca. 0.5 to 20 mg/L in the HPLC standards solutions).

DOC concentrations measured after 1, 2 and 3 days at 30°C (followed by 24 h at 20°C) were 1.06, 0.70 and 1.23 mg/L, respectively. These are most likely due to the previously mentioned additional peaks seen in the HPLC chromatograms at the dead time.

Days	DOC concentration [mg/L]	pH
1	1.06	6.3
2	0.70	5.7
3	1.23	4.2

 

The water solubility of the test item is below 0.54 mg/L, which is the detection limit of the HPLC method used.

Discussion
During the test, the temperature ranged from 28.9 to 29.3 °C in the saturation phase and was thus not in the range of 30 ± 0.5 °C. This should not have had any significant influence on the results of the study, as the measured temperatures during the (relevant) equilibration phase were in the range of 20 ± 0.5 °C as given in the guideline.

Note: The substance appears insoluble in water. A limit test up to the detection limit of the analytical method was done.

Description of key information

< 0.54 mg/L at 20 °C (OECD 105, Flask Method)

Key value for chemical safety assessment

Water solubility:

0.54 mg/L

at the temperature of:

20 °C

Additional information

Dissolved organic carbon concentrations were measured, water solubility was below the analytical method used (HPLC).