Registration Dossier

Administrative data

Endpoint:
adsorption / desorption: screening
Data waiving:
study scientifically not necessary / other information available
Justification for data waiving:
the study does not need to be conducted because the physicochemical properties of the substance indicate that it can be expected to have a low potential for adsorption
other:
Justification for type of information:
The inorganic susbtance is soluble water and in the soluble form will be dissociated. The behaviour in soil will therefore be depending on the counter ions present in the soil and the association of Zr4+ ions to the soild surface. This cannot be predicted from laboratory screening studies. Zirconium in soil is mostly present as insoluble carbonate and oxide; therefore, it will not be mobile in soil. The solubility in soil and its mobility may increase due to the formation of soluble complexes with organic matter in soil, with a lower soil pH potentially facilitating complexation
Cross-reference
Reason / purpose:
data waiving: supporting information
Reference
Endpoint:
water solubility
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
test procedure in accordance with generally accepted scientific standards and described in sufficient detail
Justification for type of information:
In-house data assessment.
Solublity assessed at different pH and assessed in hardened water
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 105 (Water Solubility)
Principles of method if other than guideline:
Solubility at range of pH was investigated as has relevance for environmental and toxicological assessments.
Solublity in hardend water at low concentrations was also assessed for environmental relevance
GLP compliance:
no
Type of method:
flask method
Specific details on test material used for the study:
Batch No : D-02-4057
Key result
Water solubility:
> 500 g/L
Conc. based on:
test mat.
Temp.:
20 °C
pH:
ca. 1.9
Remarks on result:
completely miscible
Remarks:
pH unadjusted
Water solubility:
> 20 g/L
Conc. based on:
test mat. (total fraction)
Temp.:
20 °C
pH:
ca. 3
Remarks on result:
other: pH buffered for evaluation of solubility at different pH
Water solubility:
< 1 g/L
Conc. based on:
test mat. (total fraction)
Temp.:
20 °C
pH:
ca. 4
Remarks on result:
other: Buffered to pH 4
Water solubility:
< 100 mg/L
Conc. based on:
test mat.
Loading of aqueous phase:
100 mg/L
Temp.:
20 °C
pH:
ca. 3
Remarks on result:
other: Environmental hardness ca 100 mg/l caCO3
Water solubility:
ca. 1 mg/L
Conc. based on:
test mat.
Loading of aqueous phase:
1 mg/L
Temp.:
20 °C
pH:
4.3
Remarks on result:
other: Evironmental hardness ca 100 mg CaCO3
Details on results:
The data indicate reduced solubility in water when buffered to > pH 3
When repeated in hardened water, but no buffer, solublity was ca 1 mg/l based on test material, with a pH of 4.3 recorded.
A loading of 20 g/l in distilled water, buffered to pH 3 was soluble, but when 1 g/l was in hardened water, it was insoluble at pH 3
Conclusions:
The solubility is pH dependant with reduced solublity at pH 4 or more, suggesting formation of hydroxide / oxide
The substance supplied is typically in acidic solution
The data indicate reduced solubility in water when buffered to > pH 3
When repeated in hardened water, but no buffer, solublity was ca 1 mg/l based on test material, with a pH of 4.3 recorded.
A loading of 20 g/l in distilled water, buffered to pH 3 was soluble, but when 1 g/l was in hardened water, it was insoluble at pH 3

Data source

Materials and methods

Results and discussion

Applicant's summary and conclusion