Slimes and Sludges, copper electrolytic

Water solubility

Administrative data

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: No GLP study but other quality assurance

Cross-reference

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2010

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

GLP compliance:

no

Remarks:

other quality assurance

Type of method:

flask method

Test material

Test material information

Constituent 1

Reference substance name:

Slimes and Sludges, copper electrolytic

EC Number:

266-972-5

EC Name:

Slimes and Sludges, copper electrolytic

Cas Number:

67711-95-9

Molecular formula:

Not applicable

IUPAC Name:

slimes and sludges, copper electrolytic

Details on test material:

Test material was dried before sending to test labs. Sampling of representative samples was made according to Sampling protocol of the REACH Copper Consortium (iuclid 1.4 attachment).
B6 anodic slime from primary smelter (site 1a, not decopperized) (representative, dried, homogenized) lab code: 09TT03746
B6 anodic slime from primary smelter (site 1b, decopperized) (representative, dried, homogenized) lab code: 09TT03745
B6 anodic slime, site 2A lab code: 09TT06661
B6 anodic slime, site 2B lab code: 09TT06662

Results and discussion

Any other information on results incl. tables

Table 5 presents measured pH range and average metal concentrations for the samples. Substances with solubility <10 mg/l are considered low-soluble and those with solubility <1 mg/l are considered poorly soluble /38,43/.

The pH was low especially with the samples 09TT03745, 09TT06661 and 09TT06662. High solubility was obtained for Cu (163-5450 mg/l) and for S (159-3467 mg/l) from all samples. The concentrations of Cu and S were further increasing from the samples 09TT06661 and 09TT06662. In addition, the concentration of Ag from the sample 09TT0375, As from other samples except for 09TT03746, Fe from sample 09TT06662, and Ni from samples 09TT03745 and 09TT03746 was considerable. The standard method involves three tests, which is not enough for a statistical analysis.

 

Table 5: Average water solubility calculated from the 14-16 or 24-26 days shaking tests.

	Sample code	09TT03745	09TT03746	09TT06661	09TT06662
		Average or range	Average or range	Average or range	Average or range
pH		1.97-2.03	3.98-4.19	2.33-2.36	2.23-2.23
ICP Ag		194	1.3	<0.2	0.2
ICP Al	mg/l	0.9	<0.2	2.7	0.7
ICP As	mg/l	755	2.1	61	58
ICP Bi	mg/l	-	-	<1	<1
ICP Ca	mg/l	-	6.4	19	4.3
ICP Cd	mg/l	<0.1	-	-	-
ICP Co	mg/l	6.8	0.3	<0.1	<0.2
ICP Cr	mg/l	0.1	<0.1	<0.2	3.1
ICP Cu	mg/l	5450	1867	163	1173
ICP Fe	mg/l	5.4	<0.2	3.6	82
ICP K	mg/l	<2	<2	<3	<3
ICP Mg	mg/l	1.2	0.3	4.7	0.6
ICP Mn	mg/l	<0.2	<0.2	0.3	1.2
ICP Na	mg/l	7.7	3.6	10	1.2
ICP Ni	mg/l	306	63	0.7	3.7
ICP Pb	mg/l	5.2	5	4.2	2.7
ICP S	mg/l	3467	1081	159	690
ICP Sb	mg/l	2.3	2.7	3.9	3.3
ICP Si	mg/l	0.9	1.6	8.4	3.1
ICP Sn	mg/l	<0.2	<0.2	<0.2	<0.2
ICP Te	mg/l	<0.2	<0.2	2.5	6.7
ICP Zn	mg/l	1.7	0.4	0.1	0.1

 

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information): other: poorly soluble in preliminary test
Preliminary test did not indicate any solubility of the substance. Flask method test was performed on representative sample of the UVCB, a complex metal containing substance. Validity of the reported results confirmed by Harlan Lab (V. Gretton, 2010)

Executive summary:

Classic definition of solubility do not apply to the UVCB, who is a complex metal containing substance. The usually accepted meaning in that case is (according to ECHA Guidance on information requirements and chemical safety assessment Chapter R.7a) " the composition of the aqueous solution formed at equilibrium under a defined set of conditions". Temperature and the amount of substance added per unit volume of water (i.e. the loading) are the main factors to consider. It was not always possible to establish equilibrium of all components; therefore, time and type of agitation of the vessels have been described. Aqueous solubilities were reported in mg/l.

For this UVCB, preliminary result demonstrated that substance is poorly soluble in water. Major results from the additional flask test were: with a loading of 5g/100ml, and shaking over 24 -26 days, most constituents showed poor to low solubilities, with the exception of Cu, S, Ni, As, Ag, Pb and Ca (high to moderate) as well as Na, Mg, Co, Sb, Si and Zn (moderate to low). The pH ranged from 1.97 to 2.03, 3.98 to 4.19, 2.33 to 2.33 and 2.23 to 2.23, respectively.

Under these conditions, the report acknowledges that stated solubilities may be higher than reality for some samples (e.g. due to abrasion, difficult to remove tiny undissolved particles, etc).

The reported results from OECD 105 are therefore indicative for the behaviour of the UVCB in water. For the purpose of assessing environmental fate and behaviour of this difficult to test complex metal containing substance, Transformation/dissolution test would however be more appropriate.