Copper sulphide

Endpoint summary

Additional information

Approach and data-selection for the environmental hazard assessment

 

In accordance to the copper RA,the environmental hazard assessment is based on tests carried out with soluble copper species.

 

- Studies reporting quantitative dose responses of Cu2+ ions, delivered from soluble copper compounds to aquatic and terrestrial organisms are used for the assessment.

- Bioavailability of the Cu2+ ions in both laboratory tests and in the environment may be affected by abiotic factors, (such as pH, alkalinity, hardness and DOCfor the water compartment) and therefore copper bioavailability is considered for the interpretation of the copper effects data.  

 

Approach for Environmental classification

 

The high quality short term effects records retained for the hazard classification of copper, discussed by the competent authorities for EU classification and Labelling have been included in the IUCLID data-base. 

 

For acute and chronic classification, information on acute (short term EC50 values) and chronic (long term NOEC/EC10 values) effects of soluble copper compounds to freshwater organisms (fish, invertebrates, algae and aquatic plants) are included in the IUCLID. Consdering the large amount of information available, only high quality data derived from standard testing protocols and species were retained.  Further considering the data-richness of the copper database, data summaries were carried out: when 4 or more acceptable  L(E)C50/NOEC values are available for the same species, the geometric mean of the toxicity values was used as a representative toxicity value for that species instead of the lowest value for the species.  

Considering the crucial importance of pH of the test media on the copper solubility and ecotoxicity, for the acute and chronic toxicity endpoints, 3 pH categories were distinguished within the acute and chronic ecotoxicity database: pH 5.5-6.5, >6.5-7.5 and >7.5-8.5. The lowest species-specific acute L(E)C50 and chronic NOEC values at the three pH levels and across pHs were selected as final environmental classification reference values.   

 

Approach for PNEC derivation

 

All high quality and ecological relevant chronic data (NOECs and EC10s) (also from non-standard protocols) were retained for the PNEC derivation. This resulted in a large amount of reliable and relevant environmental effects data of soluble copper compounds for a broad range of relevant species, covering key ecological compartments (freshwater, marine waters, freshwater sediments, terrestrial, sewage treatment plants). 

The assessment on the environmental hazards recognizes that copper is a natural element and essential nutrient and therefore important additional information of relevance to the PNEC derivations for the freshwater and marine compartments are retained.

-  Effects due to copper deficiencyin addition to the effects due to copper excess are reported. 

 - Information from scientific studies designed to elucidate the mechanism of action of Cu-ions are reported.  

-       Toxicity from waterborne and dietary exposure routes are evaluated

-       Single species as well as multi-species laboratory or field test set-ups are assessed.  

-       Considering that both the added and the background copper concentrations may contribute to the observed effects, this risk assessment implements the total risk approach.  Information on background variability (in culture media and natural European environments (water, sediments, soils)) and its influence on a number of biological/ecological processes (e.g. optimal concentration ranges, acclimation/adaptation, field community responses) is nevertheless crucial for the derivation of ecological relevant PNEC values and are therefore considered in the chemical safety report.

 

Derivation of reference values for environmental classification

 

Acute freshwater reference values for classification

 

All data and a synthesis of the species mean/lowest acute ecotoxicity data are given in Annex 2 (Table 2A) and Table 1. After data selection, as discussed above, 451 high quality acute data points were retained. For the algae 66 individual data points were selected for 3 standard species (Pseudokirchnerella subcapitata,Chamydomonas reinhardtiiandChlorella vulgaris). For the invertebrates 123 individual data points were selected for 2 standard species(Ceriodaphnia dubiaandDaphnia magna) and for the fish 262 individual data points were selected for 5 standard species (Oncorhynchus mykiss, Pimephales promelas, Lepomis macrochirus, Brachydanio rerioandCyprinus carpio).

 

Chronic reference values for classification

 

After data selection, 90 high quality chronic data points were retained. For the algae/aquatic plants, 33 individual data points were selected for 4 standard species (Raphidocelis subcapitata, Chlorella vulgaris, Chlamydomonas reinhardti and Lemna minor). For the invertebrates 23 individual data points were selected for 3 standard species(Ceriodaphnia dubia, Daphnia magna). For the fish, 34 individual data points were selected for 3 standard species (Oncorhynchus mykiss, Pimephales promelasandSalvelinus fontanilis).

 

The lowest species-specific acute L(E)C₅₀and chronic NOEC values at the three pH levels and across pHs were selected as final environmental classification reference values.    The derived values acute and chronic reference values are provided in theTable 24

 

Table:Acute and chronic reference values for soluble copper ions

pH range	Acute reference L(E)C50 (µg Cu/l)	Chronic reference NOEC (µg Cu/l)
pH 5.5-6.5	25	20
pH >6.5-7.5	35	7.4
pH >7.5-8.5	29.8	11.4
Accross pHs	34.4	14.9

  

                                                                                                                                           
Ecotoxicological dataof relevance to the of aquatic PNEC derivation

The high quality long term effects records used for the PNEC derivation of copper under the Existing Substances Regulation (TCNES) and Biocidal Products regulations (Technical meetings) have been included in the IUCLID data-base. Tests that were considered as not-reliable for the PNEC derivations have NOT been included in the IUCLID records but have been summarized in the copper RA report (2008).

 

Freshwater effects:The freshwater effect records include 139 high quality single-species chronic NOEC/L(E) C10 values from 27 different aquatic species, representing different trophic levels (fish, invertebrates, algae, aquatic plants).

 

These NOECS are carried forward for the freshwater PNEC derivation in a WOE approach.These NOECS are also carried forward as a weight of evidence for the freshwater sediment PNEC derivation using the equilibrium partitioning approach.

The copper threshold values derived for three high quality mesocosm studies, representing lentic and lotic systems and including a wide variety of potentially sensitive species (algae, invertebrates and higher plants) are used as additional WOE for the PNEC derivations of the freshwater and the sediment compartment. The records are included in section 6.6. (additional ecotoxicological information).

 

Considering the importance of understanding the mechanism of action (target tissues, dietborne versus waterborne exposures, influence of acclimation) for defining the uncertainty around the PNEC, relevant supportive papers that are critical to the understanding of the mechanism of action are included in the database.

 

Considering the importance of bio-availability for reducing the intra-species variability, the data- base includes supportive information related to the development/validation of the copper bio-availability models (so called Biotic Ligand Models) and the physico-chemistry needed for the normalization the individual NOEC values.

Considering the essential functions of copper, the data-base further includes reliable supporting papers on copper deficiency. 

 

More details are provided in the sections chronic toxicity to fish, invertebrates, algae, aquatic plants and additional ecotoxicological information.

 

Marine effects:The freshwater effect records include 56 high quality single-species chronic NOEC/L(E) C10 values from 24 different aquatic species, representing different trophic levels (fish, invertebrates, algae, aquatic plants). 

These NOEC/L(E) C10 values are carried forward for the marine PNEC derivation in a WOE approach. These NOECS are also carried forward for the marine sediment PNEC derivation using the equilibrium partitioning approach.

In response to the recommendation from TCNES and SCHER, a marine mesocosm has been carried out and these results are included in the IUCLID records. The copper threshold value derived for from this high quality marine mesocosm study, was used for as additional WOE for the PNEC derivation. The records is included in section 6.6. (additional ecotoxicological information)..

 

Considering the importance of understanding the mechanism of action for defining the uncertainty around the PNEC, supportive papers that are critical to the understanding of the mechanism of action are included in the database.

Considering the importance of bio-availability for reducing the intra-species variability, the data- base includes supportive information related to the development/validation of the marine organic carbon normalization, key to copper bio-availability in marine systems. The OC normalization model is used for normalizing the NOEC/L(E) C10 values and deriving the marine PNEC.

More details are provided in the sections chronic toxicity to fish, invertebrates, algae, aquatic plants and additional ecotoxicological information.

 

Effects for Sewage Treatment plants: Data on the toxicity tests performed with aquatic bacteria and protozoa, reported as L(E)C₅₀and NOEC values are available. The exposure time among reports varied from short term batch exposures to continuous exposures. The effects endpoints on micro-organisms covered are: heterotrophic respiration inhibition, nitrification inhibition and effects on ciliated protozoa.

More details are provided in the section micro-organisms.

Effects for freshwater sediment organisms:The freshwater sediment effect records include 62 high quality single-species chronic NOEC/L(E) C10 values from 6 different sediment- dwelling organisms that are carried forward for the sediment PNEC derivation in a WOE approach.. The data base includes additional information in support of the incorporation of bioavailability in the PNEC derivations

More details are provided in the section sediment effects