Registration Dossier

Administrative data

Endpoint:
water solubility
Type of information:
experimental study
Adequacy of study:
key study
Study period:
16-31/01/2018
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2018
Report Date:
2018

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 105 (Water Solubility)
Version / remarks:
flask method
Qualifier:
according to
Guideline:
EU Method A.6 (Water Solubility)
Version / remarks:
2008
GLP compliance:
yes (incl. certificate)
Type of method:
flask method

Test material

Reference
Name:
Unnamed
Type:
Constituent
Type:
Constituent
Type:
impurity
Test material form:
solid: bulk
Specific details on test material used for the study:
Lot/Batch Number: C000344287
Code [according to CoA]: 0481784

Results and discussion

Water solubility
Key result
Water solubility:
< 0.002 µg/L
Conc. based on:
test mat.
Loading of aqueous phase:
100 mg/L
Incubation duration:
3 d
Temp.:
20.4 °C
pH:
6.52

Applicant's summary and conclusion

Conclusions:
Under the conditions of this test (flask method; loadings 100 mg test item/L), no solubility of the test item was observed during testing from day 1 – day 3. The zirconium concentration were all below the LOD of 0.002 μg Zr/L.
Executive summary:

A study sponsored by REACH Orphan Substances Consortium Bvba was performed at Fraunhofer Institute for Molecular Biology and Applied Ecology (Fraunhofer IME, Schmallenberg, Germany) to determine the water solubility of Zirconium Oxide according to OECD 105 (flask method) [4] and Regulation 440/2008/EC A.6 [5].

Based on the preliminary results, discussion with the study monitor and according to the guideline (at least 5 times the amount needed for solubility equilibrium) a loading of 101.54 mg/L (50.77 mg/500 mL) and 100.16 mg/L (50.08 mg/500 mL) was applied in 500 mL Erlenmeyer flasks.

The test was performed in duplicate. Furthermore, samples from each vessel at each sampling point were analyzed in duplicate. Dissolved zirconium concentrations were measured by ICP-MS.

Samples were taken after 1, 2 and 3 days. The pH value of solutions containing the test item started at 6.526.62 at day one. At day two an increase of the pH value was observable (7.337.40) whereas a decrease was observable for day three (6.616.80). The same was observable for the method blanks (day one: 6.857.04; day two: 7.507.52;

day three: 6.366.51). For this reason an influence of the substance on the pH can be excluded.

Zirconium in all taken and measured samples were below the LOD of the measurement series (0.002 μg Zr/L). For this reason, calculation of the difference during the sampling could not be calculated, furthermore due to the fact that all samples were below the LOD of the measurement series a difference was not observable. Thus, the validity criteria (dissolved Zr concentrations of samples from two consecutive days did not differ by more than 15 %) as foreseen in OECD 105 [4] and Regulation 440/2008/EC A.6 [5] was met.

Under the conditions of this test (flask method; loadings 100 mg test item/L), no solubility of the test item was observed during testing from day 1day 3. The zirconium concentration were all below the LOD of 0.002 μg Zr/L.