Slags, nickel smelting

Additional ecotoxological information

Administrative data

Endpoint:

additional ecotoxicological information

Type of information:

migrated information: read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2010

Report date:

2010

Materials and methods

Principles of method if other than guideline:

Evaluate effects of copper slag crushed stone fines(1 -2mm) and stones on algae,macrophytes, zooplankton and benthic macroinvertebrates in outdoor mesocosms. The test item was applied on August 5, 2010 to a series of stainless steel enclosures in a large lined basin. The design comprises testing iron-silicate crushed stone fines and iron-silicatestones in four treatment levels each and with 2 respectively 3 replicates for each treatment level.

GLP compliance:

yes

Type of study / information:

Freshwater mesocosm, covering different trophic levels

Test material

Test material information

Constituent 1

Reference substance name:

Slag, copper smelting

IUPAC Name:

Slag, copper smelting

Details on test material:

Iron silicate stones CP 90/250 (Peute Baustoff GmbH, Hamburg) and iron silicate crushed stone fines of 1– 2 mm diameter made from the same material.
Crushed stone fines and and stones have been rinsed before delivery to the test site

Chemical and mineralogical characterization of mesocosm material was conducted by Outotec. Oy, Finland (See IUCLID 4.23)
Sample Type III, Slow cooled primary
Sample (09TT05244), crushed stone fines of 1-2 mm
Sample (09TT05245), stones crushed to < 5 mm

Results and discussion

Any other information on results incl. tables

Exposure to metals in the water ( for more data see analytical report)

In the enclosures treated with iron silicate, copper concentration increased until day 14 related to dose up to a maximum of 14 μg/L. In the sand enclosures copper concentration decreased rapidly after day 14 and from autumn to spring stayed stable around 7μg/L at the highest treatment level. In the enclosures with the iron silicate stones, copper concentrations increased slightly until spring and reached a mean of 13μg/L at 100 g/L stones in March.

For lead a fast increase of water concentrations (within the first week) was followed by a fast decrease again in the sand enclosures while the decrease was slower in the stone enclosures. Maximum concentrations were below 2 μg/L in the sand and below 1 μg/L in the stone enclosures.

From the other metals, nickel and zinc concentrations increased slightly on autumn and winter and reached mean concentrations up to 2.4and 3.7 μg/L, respectively, in the 100 g/L stones enclosures. In spring 2010 mean concentrations in all other treatment levels were close to control levels. No clear trends were found for the other metals (except of iron).

Thus, the iron silicate crushed stone fines resulted in a dose related short-term increase

of some metals, i. e. Cu and Pb in the water phase while metal concentrations in the enclosures including iron silicate stone increased more slowly and stayed relatively stable until March 2010

Metals in the sediment have only been analysed yet.

No data available yet on metal concentrations in biota

Effects

 

The effect classes assigned to the different treatments and endpoints are summarized in Table 1.

Based on guidance for summarizing micro- and mesocosm studies in the context of risk assessment of plant protection products in the EU the following effect classes were used:

1 No effects: no (statistically significant) effects observed or no clear causal relationship

2 Slight and transient effects: Effects reported as ‘slight’ or ‘transient’, or other similar

descriptions, statistical significance only on isolated (non consecutive sampling

dates)

3 Pronounced temporary effects: Clear response with statistical significance on at

least two consecutive sampling dates, but total period of effects < 8 weeks

5 Pronounced effects over more than 8 weeks

 

Phytoplankton

The pigment analysis revealed direct and indirect short-term effects of 25 g/L sand and 100 g/L stones .Because statistically significant effects on green algae at the 100 g stones/L were found in autumn 2009 and spring 2010, these were preliminary considered as potential class 5 effects. Temporary (< 2 weeks) and slight effects on chromophytes directly after application were found at 50 g/L stones which were considered as class 2 effects.

Based on algae cell counts, the analysis has not conducted any clear long-term effects on the community level yet. However, for some taxa statistically significant differences for controls over 8 weeks or more were found at the highest sand respectively stone concentration (class 5). In contrast to this, at the lower treatment levels only no, slight or temporary effects were found (class 1 – 3).

Cryptomonas erosa/ovataseems to be the most sensitive species in the stone enclosures with effects in autumn 2009 and spring 2010 at 100 g/L stones (effect class 5).

ForKatablepharis ovalisslight effect in the sand treatments were found with significance on one sampling day only (day 14) at 6.25 g/L and higher which was considered as a class 2 effect.

 

Periphyton

No treatment related consistent significant effects of the crushed stone fines were found by the Williams-test for total chlorophyll a or the four groups.

Significantly lower values for Cryptophytes on day 249 at 6.3 g/L and higher were classified as class 2 because restricted to one sampling date yet. For the stones, chlorophyll a concentrations were significantly lower at 100 g/L on day 84 and 110. However, deviations to the range of controls were small and thus, this was considered as class 2 effect.

 

Macrophytes

Potential treatment effect were only found forChara intemediawhich was significantly less abundant at 25 g/L sand over some samplings; coverage was below the range of controls until October 2009. Thus, effects of the sand onCharawere considered as class 5 effects. In spring 2010, abundance at 25 g/L was only slightly reduced. Lower coverage on one sampling date at 100 g /L stones was considered as class 2.

 

Water parameters indicating photosynthetic activity

Oxygen concentrations, pH, and conductivity were used as indicators for total photosynthesis

in the enclosures. Based on pH as the most sensitive parameter, short-term effects (class 3) were found at 25 g/L sand while in the highest stone treatment level, significant differences were found in autumn 2009 and spring 2010 which were therefore considered as class 5 effects. However, all differences to controls were slight and without likely effects on other biota.

 

Zooplankton

The available data for the zooplankton indicate only slight and/or temporary effects on rotifers and cyclopoids directly after start of exposure at the highest sand treatment level (25 g/L). For other taxa, significant differences to controls (increase or decrease) were only found at single not consecutive sampling dates and also the community level analysis revealed no clear effects yet. In the stone enclosures statistically significant effects were only found for single sampling dates which in most cases indicated higher abundances at 100 g/L stones. Thus, based on the available data yet, class 2 effects

are assigned to the highest treatment levels of sand and stones.

 

Macrozoobenthos

Indications of direct or indirect temporary effects on the macrozoobenthos were found only for the highest sand or stone treatment level. In most cases differences to controls were restricted to single, non- consecutive samplings (class 2). For gastropoda, significantly lower abundances at 25 g/L sand were found in November 2009 and March 2010, but not in April 2010. However, these effects were considered as class 5 effects because they were given over more than 8 weeks. For a few other taxa significant differences to control were only found on single sampling dates (class 2).

Applicant's summary and conclusion

Conclusions:

The study is of good quality. The NOEC is 12.5 g/l for slag crushed fines and 50 g/l for stones .
The study will be used for fresh water PNEC derivation

Executive summary:

Mesocosm study was performed to evaluate effects of copper slag crushed stone fines and hydraulic construction copper slag stones on algae, macrophytes, zooplankton and benthic macroinvertebrates in outdoor mesocosms.

The test item was applied on August 5, 2010 to a series of stainless steel enclosures in a large lined basin..

The basin was filled in March 2009 and thus allowed to equilibrate for > 4 months before application.

Twenty-eight enclosures, each containing approximately 2000 L of water with a sediment layer, were used to assess the impact of the test item on the indigenous species assemblages of macrophytes, phytoplankton, periphyton, zooplankton and macrozoobenthos.

The enclosures were set on June 19, 2009.

Four concentrations of copper slag crushed stone fines (1-2 mm diameter) were tested with two replicates each: 3.125, 6.25, 12.5 and 25 g/L (corresponding to mass ratios from 1:320 to 1:40).

In 12 other enclosures, four concentrations of copper slag stones were tested with three replicates each: 12.5, 25, 50 and 100 g/L (corresponding to mass ratios from 1:80 to 1:10).

Stones and crushed stone fines of basanite were introduced on August 4, 2010 in five enclosures used as controls and also with different amounts in the enclosures intended for the test item to ensure the same total amount of crushed stone fines and stones in all enclosures.

The in-life phase was planned until August 05, 2010 (365 days).

Exposure to metals in the water

In the enclosures treated with copper slag stones, copper concentration increased until day 14 related to dose up to a maximum of 14 μg/L. In the sand enclosures copper concentration decreased rapidly after day 14 and from autumn to spring stayed stable around 7 μg/L at the highest treatment level. In the enclosures with the iron silicate stones, copper concentrations increased slightly until spring and reached a mean of 13 μg/L at 100 g/L stones in March.

For lead a fast increase of water concentrations (within the first week) was followed by a fast decrease again in the sand enclosures while the decrease was slower in the stone enclosures. Maximum concentrations were below 2 μg/L in the sand and below 1 μg/L in the stone enclosures.

From the other metals, nickel and zinc concentrations increased slightly on autumn and winter and reached mean concentrations up to 2.4 and 3.7 μg/L, respectively, in the 100 g/L stones enclosures. In spring 2010 mean concentrations in all other treatment levels were close to control levels. No clear trends were found for the other metals (except of iron).

Thus, the copper slag crushed stone fines resulted in a dose related short-term increase of some metals, i. e. Cu and Pb in the water phase while metal concentrations in the enclosures including copper slag stone increased more slowly and stayed relatively stable until March 2010.

Effects:

In summary the available data until spring 2010 do not indicate any persistent adverse effects on the biocoenosis in the enclosures treated with the iron silicate crushed stone fines or stones.

Pronounced effects (class 3 or 5) of the test material are restricted to the highest sand and stone doses (25 g/L sand (1:40) and 100 g/L stones (1:10), respectively.

If potential effects were found over 8 weeks or more these were restricted to periods

after introduction of the test items or found over the winter (November to March ).

Up to 12.5 g/L sand (1:80) or 50 g/L stones (1:20) only slight effects or effects or deviations to controls restricted to single sampling dates have been found.

Therefore the NOEC is determined as 12.5 g/l for slag crushed fines and 50 g/l for stones