Manganese ores, reduced

Water solubility

Link to relevant study record(s)

Reference

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

19th December 2008 to 20th February 2009

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method A.6 (Water Solubility)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

flask method

Water solubility:

<= 0 g/L

Temp.:

20 °C

pH:

>= 6.5 - <= 8.4

Details on results:

See tables below.

Preliminary test results:

Sample number	Concentration (g/l)	Observations
1	1.0E-03	Excess test material present
2	9.0E-03	Excess test material present

Definitive test results:

Sample number	Time shaken at approx 30°C (hours)	Time equilibrated at 20°C (hours)	Manganese concentration (g/l)	Equivalent Test Material Concentration (g/l)	Solution pH
1	24	24	<1.0E-05	<2.2E-05	8.2
2	48	24	1.0E-05	2.2E-05	6.5
3	72	24	<1.0E-05	<2.2E-05	8.4

 

Overall manganese concentration : ≤ 1.0E-05 g/l at 20 ±0.5°C

Overall equivalent test material concentration: ≤ 2.2E-05 g/l at 20±0.5°C

No significant manganese concentration (<0.01 mg/l) was detected in the matrix blank on analysis.

The preliminary water solubility test indicated that the column elution method should have been performed as the solubility was less than 1 x 10^-2g/l. However, in the absence of a suitable volatile organic solvent for the coating of inorganic substances onto a suitable support material, this method could not be used. Experience has shown that when the support material is coated by substances present as a suspension in a solvent, as opposed to a true solution, the test material breaks away from the support material over time, migrating into the reservoirs and invalidating the determination.

Conclusions:

The water solubility of the test material has been determined to be ≤ 1.0E-05 g/l of manganese in solution at 20±0.5°C. This was equivalent to ≤ 2.2E-05 g/l of test material at 20±0.5°C based on the manganese content of the test material.

Executive summary:

The water solubility of the test material was investigated in accordance with the standardised guideline, EU Method A.6, under GLP conditions, following the Flask Method.

Under the conditions of the study the water solubility of the test material was determined to be ≤ 1.0E-05 g/l of manganese in solution at 20 ± 0.5°C. This is equivalent to ≤ 2.2E-05 g/l of test material at 20 ± 0.5°C based on the manganese content of the test material.

 

Description of key information

The substance has very poor solubility in water (EU method A6). The water solubility of the test material has been determined to be ≤ 1.0E-05 g/L of manganese in solution at 20 ± 0.5 °C. This was equivalent to ≤ 2.2E-05 g/L of test material at 20 ± 0.5 °C based on the manganese content of the test material. This result indicates the substance can be regarded as essentially insoluble.

Key value for chemical safety assessment

Water solubility:

0.022 mg/L

at the temperature of:

20 °C

Additional information

The water solubility of the test material was investigated in accordance with the standardised guideline, EU Method A.6, under GLP conditions, following the Flask Method. The study was awarded a reliability score of 1 in accordance with the criteria set forth by Klimisch et al. (1997).

Under the conditions of the study the water solubility of the test material was determined to be ≤ 1.0E-05 g/l of manganese in solution at 20 ± 0.5°C. This is equivalent to ≤ 2.2E-05 g/l of test material at 20 ± 0.5°C based on the manganese content of the test material.

This result indicates the substance can be regarded as essentially insoluble.