Manganese sulphide

Water solubility

Link to relevant study record(s)

Reference

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

20/12/08 to 11/02/09

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study performed to GLP and guideline

Qualifier:

according to guideline

Guideline:

EU Method A.6 (Water Solubility)

GLP compliance:

yes (incl. QA statement)

Type of method:

flask method

Water solubility:

0.006 g/L

Temp.:

20 °C

pH:

5.7

Remarks on result:

other: This is equivalent to 6.16 mg/L

Table1: Preliminary test results

Sample	Concentration (g/l)	Observations	Solution pH
1	1.1 x 10^-2	Significant excess un-dissolved test material was observed at the base of the flask below a clear colourless solution	7.4
2	1.3 x 10^-3	A trace quantity of excess un-dissolved test material was observed at the base of the flask below a clear colourless solution	7.4

The preliminary estimate of water solubility was less than 1.3 x 10 ^-3g/l (as test material)

Table 2: Mean concentration (g/l) of manganese and mean equivalent test material concentration (g/l)

Sample	Time shaken at ~30°C (hours)	Time shaken at ~20°C (hours)	Manganese concentration (g/l)	Equivalent manganese sulphide concentration (g/l)	Solution pH
1	24	24	4.20 x 10^-3	6.66 x10^-3	5.7
2	48	24	3.67 x 10^-2	5.81 x 10^-3	5.7
3	72	24	3.79 x 10^-3	6.00 x 10^-3	5.8

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:

Interpretation of results: slightly soluble (0.1-100 mg/L)
The water solubility of the test material has been determined to be 3.89 x 10-3 g/l of manganese in solution at 20.0 ± 0.5°C This is equivalent to 6.15 x 10-3 g/L (6.15 mg/L) of manganese sulphide in solution based on the theoretical manganese content of the test material. Therefore the test material is considered to be very slightly soluble.

Executive summary:

The water solubility of the test material was assessed according to EU Method A.6 using a flask method.

Under the conditions of the study the water solubility of the test material has been determined to be 3.89E-03 g/L of manganese in solution at 20.0 ± 0.5 °C This is equivalent to 6.15E-03 g/L (6.15 mg/L) of manganese sulphide in solution based on the theoretical manganese content of the test material.

Description of key information

The water solubility of the test material has been determined to be 3.89E-03 g/L of manganese in solution at 20.0 ± 0.5 °C This is equivalent to 6.16E-03 g/L or 6.15 mg/L of manganese sulphide in solution based on the theoretical manganese content of the test material. Therefore the test material is considered to be very slightly soluble.

Key value for chemical safety assessment

Water solubility:

6.15 mg/L

Additional information

The water solubility of the test material was assessed according to EU Method A.6 using a flask method.

Under the conditions of the study the water solubility of the test material has been determined to be 3.89E-03 g/L of manganese in solution at 20.0 ± 0.5 °C This is equivalent to 6.15E-03 g/L (6.15 mg/L) of manganese sulphide in solution based on the theoretical manganese content of the test material.