Copper di(acetate)

Additional information on environmental fate and behaviour

Administrative data

Endpoint:

additional information on environmental fate and behaviour

Type of information:

calculation (if not (Q)SAR)

Remarks:

Migrated phrase: estimated by calculation

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: The estimations are based on model that has been developed to assess the the long-term fate and effects of metals in the environment

Cross-reference

Cross-reference 1

Reason / purpose for cross-reference:

reference to same study

Cross-reference 2

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2010

Materials and methods

Principles of method if other than guideline:

Copper removal from the water column was assessed (1) generically, simulating a standard lake environment (EUSES), (2) from a freshwater mesocsm with continuous addition of copper sulphate (Shaefers et al,200") (3) from2 field studies following yearly applications and (4) from one field study, following continuous applications.

(1) the physical parameters of the generalized lake will be based on regional distribution parameters from the EUSES program (RIVM, 2004). Specifically, time variable TICKET-UWM simulations will be performed to assess copper removal from the water column relative to the definition of rapid removal for soluble metals of greater than 70% removal in a 28-day period (Institute for Health and Consumer Protection, 2009).

(2) from the mesocosm study, with copper sulphate additions at 5 doses during 4 months - reported in Schaefers et al, 2003 (section 6.6)

(3) Removal of copper the field was further assessed from 2 lakes:
- Lake Courtille, a shallow, polymictic, and eutrophic lake to which alum and copper sulfate CuSO4 ∙5H2O) were dosed annually since 1998 - at the beginning of the summer. In the summer 2000, dissolved, colloidal, and particulate copper concentrations (and several other water quality parameters) were monitored following copper sulfate application (Van Hullebusch et al., 2002b).
- The Saint Germain les Belles Reservoir is located in the Limousin region of France. IAfter an aluminum sulfate addition in the spring 2001, failed to control cyanobacteria, copper sulfate was added to in the summer at a concentration of 196 µg/L (as Cu). Following copper sulfate addition, copper dynamics and distribution in the water column were monitored by Van Hullebusch et al. (2003b, 2003c).

(4) The data from the MELIMEX (MEtal LIMnological EXperiment) study , having continuous copper additions to enclosures of Lake Baldegg (Lucerne, Switzerland) were also assessed.

GLP compliance:

no

Type of study / information:

Model calculatations and literature reviews

Test material

Test material information

Constituent 1

Reference substance name:

soluble copper

IUPAC Name:

soluble copper

Results and discussion

Any other information on results incl. tables

(1) Considering the standard lake model defined in EUSES as a basis for the classification, model calculations were done following the EUSES model of the world and using the copper-specific Kd values derived in section 5.4.1. (log K 4.48). The calculations demonstrate that 70% removal is reached within 4.7 days after copper addition. Additional sensitivity analysis were carried out to assess the removal at different pHs and corresponding modelled Kds (WHAM speciation model calculations)- these calculations confirm that Cu is rapidly removed (>70% within 28 days).

(2) In the freshwater mesocosm study (Schaefers et al, 2003- see section 6.6), a half life of around 4 days was calculated. To keep the dissolved copper concentrations constant in the systems, over the whole treatment period (4 months), the systems were treated with amounts about 10 times (lowest nominal concentration) to 12 times (highest nominal concentration) more than needed for initial installation of the nominal concentration.

(3) Assessment of 2 field experiments with intermettent copper dosing ( LakeCourtilleand the Saint Germain les Belles Reservoir lakes yearly dosed with copper), shows that the Cu RA logK_Dis reasonably consistent with the observed values. This provides support for continued use of the Cu RA logK_Dvalue as a typical value.  Since both waterbodies are shallow, polymictic lakes, wind-driven resuspension is expected to play a role in copper dynamics in the water column. It is worthwhile to note that even if long-term resuspension does in fact occur, for both waterbodies, > 70% removal in less then 28 days was observed. The information therefore validates the results from the model simulations.

(4) Assessment of the field experiment with continuous dosing - MELIMEX limno-corrals lake - indicate that following termination of copper loading demonstrate copper removal that does not meet the rapid removal benchmark because of a low settling velocity, low distribution coefficient, and low suspended solids concentration.  A combination of such exceptional conditions does not allow to reach the benchmark.

Applicant's summary and conclusion

Conclusions:

Dissolved copper, added to a standard lake model (EUSES) is removed by >70% within 5 days. Sensitivity analysis and validations from 1 mesocosm study with continuous copper dosing at 5 concentrations and 2 lake systems with intermettent copper dosing also demonstrate that copper is rapidly removed, in excess of 70% within 28 days. For one study, with exterme combinations of low settling rate, low suspended solids and low distribution coefficients (much lower then defined in the EUSES model) the removal rats was <70% in 28 days. Such extreme conditions are not considered as relevant to a hazard classification.

It is therefore concluded that for typical conditions in Europe, copper-ions are rapidly removed from the water-column. This conclusions is critical to the chronic environmental classification.

It is therefore concluded that copper ions are rapidly removed from the water column.

Executive summary:

The conclusions are formulated as follows:

·        For a standard lake environment consisting of the EUSES model lake parameters, copper removal from the water column satisfies the definition for rapid removal of 70% dissolved copper removal in 28 days;

·        For a standard lake environment consisting of the EUSES model lake parameters, assessed at pH 6 to 8, copper removal from the water column satisfies the definition for rapid removal of 70% dissolved copper removal in 28 days;

·        For the Mesocosm sudy with a range of copper loadings, the measured data indicate rapid removal of copper (i.e. greater than 70% in 28 days);

·        For the whole-lake spike addition studies (LakeCourtilleand Saint Germain les Belles Reservoir), TICKET-UWM results, in concert with the measured data indicate rapid removal of copper (i.e. greater than 70% in 28 days);

·        Hypothetical TICKET-UWM simulations modeling the removal of copper in the MELIMEX limno-corrals following termination of copper loading demonstrate copper removal that does not meet the rapid removal benchmark because of a low settling velocity, low distribution coefficient, and low suspended solids concentration.