Registration Dossier

Data platform availability banner - registered substances factsheets

Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Physical & Chemical properties

Water solubility

Currently viewing:

Administrative data

Link to relevant study record(s)

Reference
Endpoint:
water solubility
Type of information:
experimental study
Adequacy of study:
key study
Study period:
17 September 2018 to 21 November 2018
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)
Version / remarks:
2016
Deviations:
no
Qualifier:
according to guideline
Guideline:
EPA OPPTS 830.7840 (Water Solubility)
Version / remarks:
1998
Deviations:
no
GLP compliance:
yes
Type of method:
column elution method
Key result
Water solubility:
< 0.001 mg/L
Conc. based on:
element (dissolved fraction)
Remarks:
dissolved Niobium
Temp.:
20 °C
pH:
>= 7.4 - <= 7.6
Details on results:
PRELIMINARY TEST
- The content of dissolved Niobium in the water samples was ≤ 0.00061 mg/L.

MAIN STUDY
- At a flow rate of 24 mL/h, the coefficient of variation (CV) (n = 10) was > 30 %. Therefore, sampling at this flow rate was repeated. The coefficient of variation (CV) (n = 10) was ≤ 30 % at 12 mL/h and at the repeat at 24 mL/h. It demonstrated that the system was equilibrated at these flow rates.
- At these flow rates, the analysed Niobium concentrations were far below that of the lowest calibration level. The analysed Niobium concentrations are therefore reported to be below that of the lowest calibration standard multiplied by the dilution factor (i.e. < 0.000728 mg/L).
- The turbidity of the eluates was < 0.2 NTU. According to this, no undissolved particles were detected in the eluates.
- Background response of Niobium was detected in the pre-treated samples from the blank column. These responses were comparable with the responses in the test samples.

Table 1: Main Study - Water Solubility of Dissolved Niobium

Flow Rate (mL/h)

Sample No.

Niobium Concentration Analysed

pH

Individual1(mg/L)

Mean2(mg/L)

CV (%)

Mean3(mg/L)

MD (%)

244

1

0.00029

0.000716

1184

 

 

7.4

2

0.00028

3

0.00080

4

0.00025

5

0.00026

6

0.0026

7

0.00025

8

0.00025

9

0.0018

10

0.00028

12

1

0.000285

0.000227

12

0.000209

13

7.4

2

0.00165

3

0.000385

4

0.00022

5

0.00021

6

0.00027

7

0.00020

8

0.00021

9

0.00020

10

0.00021

24

1

0.00017

0.000198

23

 

 

7.6

2

0.00017

3

0.00030

4

0.00018

5

0.00017

6

0.00023

7

0.00018

8

0.00017

9

0.00016

10

0.00017

 

1: Obtained by extrapolation of the calibration curve.

2: Mean of the concentrations obtained at one flow rate.

3: Mean of the concentrations obtained at the flow rate of 12 mL/h and the repeated flow rate of 24 mL/h.

4: Coefficient of variation was >30 %, therefore sampling at this flowrate was repeated.

5: This value was not used for calculation of the mean because the system had not reached equilibrium yet.

6: The mean concentration obtained in the corresponding blank was 0.00020 mg/L.

7: A comparable mean concentration of 0.00020 mg/L was obtained in the corresponding blank.

8: A comparable mean concentration of 0.00017 mg/L was obtained in the corresponding blank.

9: The analysed concentrations were far below the lowest calibration level and are therefore reported to be below the lowest calibration standard, multiplied by the dilution factor (i.e. < 0.000728 mg/L).

Conclusions:
Under the conditions of this study the water solubility of dissolved Niobium at 20 °C was < 0.000728 mg/L.
Executive summary:

The water solubility of the test material was investigated in accordance with the standardised guidelines OECD 105, EU Method A6 and OPPTS 830.7840, under GLP conditions.

It proved not possible to dissolve the test material in nitric acid, nitric acid/hydrogen peroxide and hydrochloric acid. The test material dissolved in hydrofluoric acid but during removal of excess hydrofluoric acid using boric acid, the test material precipitated as a white solid.

For quantitative analysis, stock and calibration solutions with a known content are needed. As an alternative, an analytical standard of Niobium was purchased and used for analysis. As a result, concentrations measured are dissolved Niobium concentrations.

The column elution method was applied for the determination of the mass concentration of dissolved Niobium in water. The pH of the aqueous samples was 7.4 and 7.6.

Under the conditions of this study, the water solubility of dissolved Niobium at 20 °C was < 0.000728 mg/L.

Description of key information

Under the conditions of this study the water solubility of dissolved Niobium at 20 °C was < 0.000728 mg/L.

Key value for chemical safety assessment

Water solubility:
0.001 mg/L
at the temperature of:
20 °C

Additional information

The water solubility of the test material was investigated in accordance with the standardised guidelines OECD 105, EU Method A6 and OPPTS 830.7840, under GLP conditions. The study was awarded a reliability score of 1 in accordance with the criteria set forth by Klimisch et al. (1997).


It proved not possible to dissolve the test material in nitric acid, nitric acid/hydrogen peroxide and hydrochloric acid. The test material dissolved in hydrofluoric acid but during removal of excess hydrofluoric acid using boric acid, the test material precipitated as a white solid.


For quantitative analysis, stock and calibration solutions with a known content are needed. As an alternative, an analytical standard of Niobium was purchased and used for analysis. As a result, concentrations measured are dissolved Niobium concentrations.


The column elution method was applied for the determination of the mass concentration of dissolved Niobium in water. The pH of the aqueous samples was 7.4 and 7.6.


Under the conditions of this study, the water solubility of dissolved Niobium at 20 °C was < 0.000728 mg/L.


 


A value of 0.001 mg/L at 20 deg C is used for risk assessment purposes.