Lead alloy, base, Pb,Sn, dross

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

Study period:

2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: in accordance to OECD

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2012

Report date:

2012

Materials and methods

Principles of method if other than guideline:

Intermediates are complex metal containing materials and as mentioned in the EU CLP guidance (annex IV) these are not simple mixtures of metals or metal compounds. The EU CLP guidance gives the following recommendation for the environmental classification of such materials: “More complex metals or metal compounds containing inorganic substances like e.g. ores and concentrates are not simple mixtures of metals or metal compounds. Justified by their intrinsic properties, the solubility properties can differ substantially from what is observed for each individual constituent of that complex substance (e.g. the rate and extent of metals release from e.g. ores/concentrates are different from the ones from simple metals). All these materials are typically not readily soluble in any aqueous medium. In addition, these materials are often heterogeneous in size and composition on a microscopic/macroscopic scale. Therefore, adequate amounts of the material could be used to evaluate the extent to which the substances can be dissolved, i.e. its water solubility and/or the extent to which the metals can react with the media to transform to water soluble forms e.g. through Transformation/Dissolution tests or possibly the Water Accommodated Fractions/loading concept.” The report therefore aims to describe the transformation/dissolution behavior through an experimental design that follows the recommendations of the OECD guidance document on transformation/dissolution (T/D) (OECD 2001)2 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)3. The developed procedures, called SOP, provide a detailed methodology for T/D that includes instrumentation requirements, reagents quality, procedures for the 7-day and 28-days full test, chemical analyses and a quality assurance program (QA/QC standards). The experimental procedure followed by CIMM can be found in annex II.
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.

GLP compliance:

no

Remarks:

other quality assurance

Type of study / information:

In accordance to CLP guidance - chapter IV. The metal concentrations released during the transformation/dissolution test are compared to the EC50s of the soluble metal ions. Toxicity is derived through the application of mixture toxicity rules, assuming additivity

Test material

Test material information

Constituent 1

Reference substance name:

Lead alloy, base, Pb,Sn, dross

EC Number:

273-701-4

EC Name:

Lead alloy, base, Pb,Sn, dross

Cas Number:

69011-60-5

Molecular formula:

Molecular weight/formula concept not applicable to Inorganic UVCB (complex metal containing substance)

IUPAC Name:

Lead alloy, base, Pb,Sn, dross

Test material form:

other: The test item received, fulfilled the <1 mm size condition. Therefore, no need for further preparation of the test item at the Test Facility was needed.

Details on test material:

The test item as received was representative of the material as it is, or will be, placed on the
market. Further preparation was not required for the test item to be suitable for use in this study
(e.g. milling, sieving, epoxy embedding…).

Results and discussion

Any other information on results incl. tables

The temperature of the test solutions fluctuated between 21.1 and 24.0°C which was in line with the test conditions of 20 – 23°C. The pH measured in the blank and test item vessels at pH 6 varied from 5.98 to 6.05. All measured data were within the specifications of 6 ± 0.2. The dissolved oxygen concentration measured in the blank and test item vessels at pH 6 varied from 8.27 to 8.51 mg O2/L. These values are higher than the target value of ± 6 mg O2/L at 22°C which means more than 70% of the saturation concentration was in contact with the air (± 8.5 mg O2/L). The raw data of the total organic carbon content (TOC) and of the metal (Ag, As, Cd, Cu, Ni, Pb, Sb, Zn) concentrations dissolved in the test medium, measured at the Test Site WLN with the TOC analyser and the ICP–MS respectively, are presented in Annex 6. The total organic carbon content (TOC) of the modified ISO 6341 aqueous media was <1 mg/LC for the medium at pH 6. This result was within the OECD requirement of <2 mg/L C

(Annex 6).

The test medium at the start of the test and the blank control vessels during the test showed no

significant concentrations of silver, arsenic, cadmium, copper, nickel, lead, antimony and zinc

(Annex 2a to 2h). Since arsenic, cadmium and nickel showed no concentrations above their

reporting limits, these elements were only measured in the test medium at the start of the test

and the blank control and test vessels at the 28 days endpoint in order to check the outcome of

the screening test for these elements.

The following observations could be made in the test vessels with a loading of 1 mg/L Lead

alloy, base, Sn, Pb dross:

• no significant concentrations of arsenic, cadmium, cobalt, nickel, antimony and

zinc were measured.

• Small amounts of silver were measured on day 21 and the 28 days endpoint:

0.05 ± 0.2 μg Ag/L at the 28 day endpoint was measured with a between-vessel

variation of 38%. The coefficient of variation for silver exceeded the 20% quality

criterion at the 28 day sampling point.

• Higher dissolved concentrations were found for copper and lead:

o For copper an average dissolved concentration of 9.4 ± 0.4 μg Cu/L at the 7 day sampling point and 17.8 ± 0.8 μg Cu/L at the 28 day endpoint was measured with a between-vessel variation of respectively 4% and 5%.

o For lead an average dissolved concentration of 11.3 ± 0.9 μg Pb/L at the 7 day sampling point and 45.3 ± 4.7 μg Pb/L at the 28 day endpoint with between-vessel variations of respectively 8% and 10%.

Applicant's summary and conclusion

Conclusions:

Good quality study and data are critical to the assessment of the environmental hazards of the intermediate. The aim of this project is to carry out the standard chronic Transformation / Dissolution test (T/D) at 1 mg/L loading and pH 6, to evaluate the release of metals from lead intermediate sample. The results will be used for the environmental hazard classification of the material.

Executive summary:

Table with summarized results of the measured metal concentration at the 7 and 28 days endpoints - transformation/dissolution of Lead alloy, base, Sn, Pb dross @ 100 rpm at pH 6: 1 mg/L Lead alloy, base, Sn, Pb dross @ pH 6

7-d endpoints                                                       28-d endpoints

Analyte              X ± σ μg Me/L              CV (%)              X ± σ μg Me/L              CV (%)

Silver (Ag)              <0.02                            -                            0.05 ± 0.02              38

Arsenic (As)            <1                                   -                            <1                           -

Cadmium (Cd)        <0.1                                   -                            <0.1                     -

Copper (Cu)              9.4 ± 0.4                        4                            17.8 ± 0.8              5

Nickel (Ni)               <1                                   -                                   <1                      -

Lead (Pb)                11.3 ± 0.9                     8                                   45.3 ± 4.7              10

Antimony (Sb)              <1                            -                                          <1                     -

Zinc (Zn)                    <4                            -                                          <4                         -