Dicopper hydroxide phosphate

Additional ecotoxological information

Administrative data

Endpoint:

additional ecotoxicological information

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Cross-reference

Reason / purpose for cross-reference:

reference to same study

Reference

Endpoint:

additional information on environmental fate and behaviour

Type of information:

calculation (if not (Q)SAR)

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

accepted calculation method

Reason / purpose for cross-reference:

reference to other study

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 (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 calculations and literature reviews

(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 logKDis reasonably consistent with the observed values. This provides support for continued use of the Cu RA logKDvalue 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.

Conclusions:

It is 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 study 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 (LakeCourtille and 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. 

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.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2003

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

This fresh water mesocosm study is conducted in accordance to an OECD draft guideline (OECD, 1996) and recommendations of the expert workshops HARAP (Campbell et al., 1999) and CLASSIC (Giddings et al., 2002) focussing on higher tier risk assessment studies for pesticides.

GLP compliance:

no

Type of study / information:

freshwater mesocosm study, covering different trophic levels

Test material

Test material information

Constituent 1

Reference substance name:

Copper sulphate

EC Number:

231-847-6

EC Name:

Copper sulphate

Cas Number:

7758-98-7

Molecular formula:

Cu.H2O4S

IUPAC Name:

copper(2+) sulfate

Specific details on test material used for the study:

Cu2+ delivered as copper sulphate

Results and discussion

Any other information on results incl. tables

Primary production indicated by oxygen saturation and pH showed slight and temporary effects at concentrations as low as 5 µg/l (measured concentration of 9 µg Cu/L). Considerable and permanent effects started at a nominal concentration of 40 µg/l. The same threshold level (40 µg/l) was observed for significant effects on macrophyte biomass. Phytoplankton in total showed higher densities compared to controls starting at 20 µg/l (19.4 µg Cu/l measured Cu) due to indirect effects, whereas Cryptophyta species and the green algaeAnkyratended to decrease, either due to direct (copper) or indirect effects (out-competed by small green algae).

Daphnia longispinaand Phyllopoda in general were identified as the most sensitive zooplankton taxa with a NOEC of 20 µg/l. Copepoda and Rotatoria were not affected or only at the highest treatment level. No effects could be detected for macroinvertebrates (Chironomidae, Tubificidae, snails).

Applicant's summary and conclusion

Conclusions:

Based on the 17 most sensitive geometric mean NOEC values for the mesocosm species, a SSD- HC5-50 of 19.6 µg Cu/L was derived from the log-normal distribution.

Executive summary:

This study is considered as a very high quality study: it is conducted in accordance to an OECD draft guideline (OECD, 1996) and recommendations of the expert workshops HARAP (Campbell et al., 1999) and CLASSIC (Giddings et al., 2002) focussing on higher tier risk assessment studies for pesticides. The study represents a conservative scenario with respect to:

- poor nutrient status (oligotrophic system), low hardness and DOC values resulting in a high proportion of free copper ions compared to meso- and eutrophic ecosystems,

- high exposure and resulting direct effects due to the frequent dosing with copper to maintain constant copper levels in the water body leading to short term exceeding of the complexation capacity,

- missing (re-)colonisation and resulting recovery (microcosm are located in a green house),

- high statistical power due to reduced variability and enhanced comparability between systems,

- covered seasons comprising sensitive stages of different life history traits (r, K).

 

The study NOAEC of 20 µg Cu/L is used to assess the protectiveness of the single species PNEC for multi-species systems.

 

Species-specific geometric mean NOEC values, indicative of no negative effects on the populations (abundance) were quantified for 17 mesocosm species (Table 3 34).  In addition to these 17 NOECs, several species-specific NOECs are situated at or above the highest concentration tested (160 µg Cu/L) and several species NOECS are related to increased growth/abundance with increased copper concentrations. The lowest geometric mean NOEC was observed for Rhodomonas minutes (17 µg Cu/L). Based on the 17 most sensitive geometric mean NOEC values for the mesocosm species, a SSD- HC5-50 of 19.6 µg Cu/L was derived from the log-normal distribution (ETX-RIVM tool).

 

The NOEAEC (No Observed Ecologically Acceptable Concentration) for this study was set to 20 µg/l total respectively dissolved copper. At this concentration some significant effects occurred. However, all these effects were slight and mainly temporary effects without permanent impact on ecosystem quality, neither in structure nor in function (standing crop). It is also consistent with the copper speciation measurement results indicating an increase of inorganic copper (including the biological active species) at concentrations above 20 µg/L and the HC5-50 (19.6 µg Cu/L), calculated from the most sensitive geometric mean NOEC values.