slag, copper smelting

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:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: in accordance with OECD guidline

Cross-reference

Reason / purpose for cross-reference:

reference to same study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2010

Report date:

2010

Materials and methods

Principles of method if other than guideline:

Transformation/dissolution behavior of copper slag was assessed through an experimental design that follows recommendations of the OECD guidance document on transformation/dissolution (T/D) (OECD 2001) and the standard operating procedures (SOP) proposed by CANMET and LISEC for the Transformation / Dissolution protocol to the ad hoc OECD Validation Management Group (VMG) .
Method is designed to determine the rate and extent to which metals and sparingly soluble metal compounds can produce soluble available ionic and other metal-bearing species in aqueous media under a set of standard laboratory conditions representative of those generally occurring in the environment.

The results of T/D tests can be compared with the eco-toxicity reference values to establish the aquatic hazard classification of the tested substance.

The transformation/dissolution test was performed to determine level of the dissolution of metals in the copper slag after 7 days period at loading of 100 mg/l at pH 6.

GLP compliance:

no

Remarks:

other quality assurance

Type of study / information:

In accordance to CLP guidance - chapter IV. The metal concentration released during the transformation/dissolution test are needed for a read-acoss of the ecotoxicity expressed as soluble metal ions (obtained from ecotoxicity tests with soluble metal compounds) to the ecotoxicity of the insoluble metal bearing materials (target substance).

Test material

Test material information

Constituent 1

Reference substance name:

Iron silicate, copper smelting and refining

EC Number:

701-480-0

Cas Number:

67711-92-6

IUPAC Name:

Iron silicate, copper smelting and refining

Details on test material:

The following sample were analysed:
Sample Code Sample form Description
2641 Bulk C1 Slag, Type I Granules, primary
2988 Bulk C1 Slag, Type I Granules, primary
3512 Bulk C1 Slag, Type I Granules, primary
5246 Bulk C1 Slag, Type I Granules, primary
2986 Bulk C1 Slag, Type II Granules, secondary
3177 Bulk C1 Slag, Type II Granules, secondary
3821 Bulk C1 Slag, Type II Granules, secondary
3503 1-2 mm C1 Slag, Type III Slow cooled, primary, stones
3181 1 -2 mm C1 Slag, Type IV Slow cooled, secondary, stones
2987 Bulk C1 Slag, Type II, Granules, secondary, Fines
3989 Bulk C1 Slag, Type III Slow cooled, primary. Fines

Sampling and sample preparation was performed according to ECI/REACH C1 Sampling Protocol.

Results and discussion

Any other information on results incl. tables

The following results on dissolved metal concentrations after 7 days transformation/dissolution tests (100 mg/L, 7 days, pH 6) were obtaoined:

Table 1. Summary of metals released from C1 samples after 7 days of transformation/dissolution test, 100 mg/L loading and pH 6. Metal releases were calculated as the difference between the mean sample release and the mean blanks release at 168 hours.= Below Detection Limit; SD= Standard Deviation.

Metal		2986 (Bulk)		2987 (Bulk)		2641 (Bulk)			2988 (Bulk)		3177 (Bulk)		3512 (Bulk)
7 days – 100 mg/L		Mean	SD	Mean	SD	Mean	SD	Mean		SD	Mean	SD	Mean	SD
Copper, mg/L	0.7		0.07	15.6	0.64	2.7	1.24	1.4		0.38	4.7	0.87	7	1.5
Nickel, mg/L	BDL		-	1.3	0.05	BDL	-	0.0		0.04	1.1	0.12	BDL	-
Arsenic, mg/L	BDL		-	BDL	-	BDL	-	0.2		0.09	BDL	-	0.2	0.07
Lead, mg/L	BDL		-	4	0.4	BDL	-	BDL		-	BDL	-	3.9	2.21
Zinc, mg/L	BDL		-	24	2.2	BDL	-	BDL		-	BDL	-	11	4.9
Aluminium, mg/L	BDL		-	BDL	-	BDL	-	BDL		-	BDL	-	BDL	-
Cobalt,mg/L	BDL		-	0.06	0.008	0.03	0.019	0.00		0.016	BDL	-	0.13	0.030
Molybdenum, mg/L	BDL		-	BDL	-	BDL	-	BDL		-	BDL	-	BDL	-
Barium, mg/L	BDL		-	BDL	-	BDL	-	BDL		-	BDL	-	BDL	-
Strontium, mg/L	BDL		-	BDL	-	BDL	-	0.0		0.12	0.1	0.08	BDL	-
Chromium,mg/L	BDL		-	BDL	-	BDL	-	BDL		-	BDL	-	BDL	-
Iron,mg/L	BDL		-	BDL	-	BDL	-	BDL		-	BDL	-	220	89
Manganese, mg/L	BDL		-	1.0	0.06	BDL	-	BDL		-	BDL	-	1.3	0.38
Selenium, mg/L	BDL		-	BDL	-	BDL	-	BDL		-	BDL	-	BDL	-
Cadmium, mg/L	BDL		-	BDL	-	BDL	-	BDL		-	BDL	-	BDL	-
Silver,mg/L	BDL		-	BDL	-	BDL	-	BDL		-	BDL	-	BDL	-
Tellurium,mg/L	BDL		-	BDL	-	BDL	-	BDL		-	BDL	-	BDL	-
Tin,mg/L	BDL		-	BDL	-	BDL	-	BDL		-	BDL	-	BDL	-
Antimony,mg/L	BDL		-	BDL	-	BDL	-	BDL		-	BDL	-	BDL	-
Silicon,mg/L	0		11	10	15	10	14	0		6	0	4	0	27

Continuence of Table 1

Metal	5246 (Bulk)		3989 (Bulk)		3181 (1-2 mm)		3503 (1-2 mm)		5244 (1-2 mm)
7 days – 100 mg/L	Mean	SD	Mean	SD	Mean	SD	Mean	SD	Mean	SD
Copper, mg/L	2.6	0.98	19.95	0.639	4.4	0.74	0.6	0.10	1.9	0.25
Nickel, mg/L	BDL	-	BDL	-	0.4	0.17	BDL	-	BDL	-
Arsenic, mg/L	BDL	-	1.35	0.090	BDL	-	BDL	-	BDL	-
Lead, mg/L	0.6	0.14	1.11	0.057	1.0	0.28	1.2	0.54	BDL	-
Zinc, mg/L	BDL	-	4	0.2	10	2	BDL	-	BDL	-
Aluminium, mg/L	BDL	-	BDL	-	BDL	-	BDL	-	BDL	-
Cobalt,mg/L	BDL	-	0.061	0.0040	BDL	-	0.09	0.054	BDL	-
Molybdenum, mg/L	BDL	-	BDL	-	BDL	-	BDL	-	BDL	-
Barium, mg/L	BDL	-	BDL	-	BDL	-	BDL	-	BDL	-
Strontium, mg/L	BDL	-	BDL	-	BDL	-	BDL	-	BDL	-
Chromium,mg/L	BDL	-	BDL	-	BDL	-	BDL	-	BDL	-
Iron,mg/L	BDL	-	BDL	-	BDL	-	BDL	-	BDL	-
Manganese, mg/L	BDL	-	BDL	-	BDL	-	BDL	-	BDL	-
Selenium, mg/L	BDL	-	BDL	-	BDL	-	BDL	-	BDL	-
Cadmium, mg/L	BDL	-	0.10	0.003	BDL	-	BDL	-	BDL	-
Silver,mg/L	BDL	-	BDL	-	BDL	-	BDL	-	BDL	-
Tellurium,mg/L	BDL	-	BDL	-	BDL	-	BDL	-	BDL	-
Tin,g/L	BDL	-	BDL	-	BDL	-	BDL	-	BDL	-
Antimony,g/L	BDL	-	BDL	-	BDL	-	BDL	-	BDL	-
Silicon,g/L	0	9	BDL	-	0	24	BDL	-	0	13

Applicant's summary and conclusion

Conclusions:

The data are of good quality and critical to the assessment of the environmental hazards of the copper slag

Executive summary:

Transformation/dissolution tests of copper slag were carried out to study its potential to release soluble available ionic and other metal-bearing species to the environment. Considering the composition of this complex material, a transformation / dissolution test was performed for 7 days at pH 6 and a loading of 100 mg/L, following the release of a broad range of metals from the samples.  

The results of the 7 days test demonstrate low release of Cu to the OECD media in the range of 0.6-6.6 μg/l from granules and stones, up to 20 μg/l from the fines. Only minor releases are recorded for some of the other metals: lead ( 0 – 3.9 μg/l ) , nickel ( 0 – 1.3 μg/l ) and Zn (0 -18 μg/l).

A control of the effect of pH in the metal release from C1 slags was performed with sample 3821, with two tests, one at pH 6 and another at pH 8, following the release of a broad range of metals The results at pH 6 showed higher release of copper, lead and zinc respect to the transformation / dissolution test performed at pH 8, only Silicon increase its release at pH 8. The releases from the pH 6 tests thus represent a reasonable worst case across the relevant pH gradient.

To assess the extrapolation of the results to all copper slags across industry the relative releases of metals ( Cu, Pb, Ni and Zin) were calculated as % metal released divided by % metal present (= potential release) at pH 6 during 7 days transformation/dissolution. This resulted in the following worst case release rates:

Granules and stones                                  Fines

-      Cu 0.67%                                           4.59%

-      Ni 1.92%                                            5.2 %

-      Pb 0.56%                                            0.56%

-      Zn 1,51%                                           1,51%

Conclusively the release of metals produced during the transformation-dissolution test can be used to evaluate of the short term and long term aquatic toxicity of copper slag and derive a aquatic hazard classification in accordance to the EU hazard classification system (CLP, Annex IV)