Slags, silicomanganese-manufg.

Additional information on environmental fate and behaviour

Administrative data

Endpoint:

additional information on environmental fate and behaviour

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

Performed in accordance to the general guidance given in the draft OECD Transformation/Dissolution protocol. The experimental design includes the refinements, agreed by the ad hoc OECD Validation Management Group (VMG), as described in the Standard Operating Procedures prepared by CANMET and LISEC

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2009

Report date:

2009

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: General guidance given in the draft OECD Transformation/Dissolution protocol. The experimental design includes the refinements, agreed by the ad hoc OECD Validation Management Group (VMG), as described in the Standard Operating Procedures prepared by CANM

Deviations:

no

Remarks:

There were no deviations in the actual tests performed.

GLP compliance:

yes

Remarks:

OECD Principles on Good Laboratory Practice (as revised in 1997), ENV/MC/CHEM(98)17

Type of study / information:

The information relates to manganese leaching out of the test substance into environmentally relevant water at pH 6, and provides a concentration of the metal in water after both 7 days (1,10 and 100 mg/L loading) and 28 days (1mg/L loading)

Test material

Test material information

Constituent 1

Reference substance name:

Slags, silicomanganese-manufg.

EC Number:

273-733-9

EC Name:

Slags, silicomanganese-manufg.

Cas Number:

69012-33-5

Molecular formula:

UVCB identified to contain the following formulae: Na2O, MgO, Al2O3, SiO2, P2O5, K2O, CaO, TiO2, V2O5, Cr2O3, Fe2O3,BaO, ZrO2, ZnO, SrO, SiMn

IUPAC Name:

Slags, silicomanganese-manufacturing

Details on test material:

- Name of test material (as cited in study report): Silicon-manganese slag
- Physical state: solid

Results and discussion

Any other information on results incl. tables

Silicon – Manganese slag: summary of the results for the 24 h screening tests, 100 mg/L loading at pH 6,7 and 8 with an agitation of 200 RPM

pH 6	Blanks			100 mg/L loading
Time, h	Mn, µg/L   S.D.			Mn, µg/L   S.D.
0	0.7		0.36	1.2		0.40
24	1.2		0.43	14.1		1.58
pH 7	Blanks			100mg/L loading
Time, h	Mn, µg/L   S.D.			Mn, µg/L   S.D.
0	0.2	0.14		0.1	0.13
24	0.1	0.07		11.1	3.53
pH 8	Blanks			100 mg/L loading
Time, h	Mn, µg/L   S.D.			Mn, µg/L   S.D.
0	0.2	0.58		0.1	0.30
24	0.0	0.30		4.9	0.92

Silicon - Manganese slag: summary of the results of transformation / dissolution tests for 7 days at 10 and 100 mg/L loading and 28 days 1mg/L loading, performed at pH 6 with 100 RPM agitation.

	Blanks		1 mg/L loading
Time, h	Mn, µg/L   S.D.		Mn, µg/L   S.D.
0	0.9	0.65	0.6	0.32
168	0.4	0.17	0.9	0.54
672	0.3	0.14	1.0	0.41
	Blanks		10 mg/L loading
Time, h	Mn, µg/L   S.D.		Mn, µg/L   S.D.
0	0.1	0.02	0.1	0.12
168	0.2	0.03	1.9	0.23
	Blanks		100 mg/L loading
Time, h	Mn, µg/L   S.D.		Mn, µg/L   S.D.
0	0.1	0.02	0.3	0.13
168	0.2	0.03	14.1	1.25

Applicant's summary and conclusion

Conclusions:

The test demonstrates low leaching of Mn from the substance, both for short-term and long-term periods is less than the background concentration of Mn in Europe.

Executive summary:

The extent of transformation/dissolution of Mn from the test substance was investigated in a study which was conducted in accordance with the standardised guideline OECD 29.

A screening test was first conducted to ascertain the pH of maximum metal release. The test substance was introduced into the aqueous media (pH 6, pH 7 and pH 8) at a single loading of 100 mg/L. After 24 hours agitation, the dissolved metal (Mn) ion concentration was measured. The highest level of Mn release was from the pH 6 solution and so the definitive study was conducted at this pH.

In the definitive study, three different test substance loadings were investigated (1, 10 and 100 mg/L). The level of Mn release was measured after a 7 day agitation period at all three loading rates. Furthermore, the level of Mn release was measured after a 28 day agitation period at the 1 mg/L loading rate only.

Under the conditions of the study, the concentrations of manganese in solution following a 7 day agitation period at test substance loading rates of 100, 10 and 1 mg/L were 14.1, 1.9 and 0.9 µg Mn/L, respectively. The concentration of manganese in solution, following a 28 day agitation period at a test substance loading rate of 1 mg/L was 1.0 µg/L.

Results of the definitive study demonstrate a low leaching of Mn from SiMn slag. The concentration after 7 and 28 days are both less than the background level in Europe (15.9 -35.8 µg/L).