Diphosphoric acid, copper salt

Endpoint summary

Description of key information

The freshwater effect records include 139 and the marine water effect records include 56 high quality single-species chronic NOEC/L(E)C10 values from 27 different aquatic species, representing different trophic levels (fish, invertebrates, algae, aquatic plants) which are used for the PNEC derivation in a WoE approach.

Additional information

Data-selection for the environmental hazard assessment

Data are available on a number of substances containing inorganic copper and read-across is justified on the basis that for the purposes of assessing the ecotoxicology of Copper (II) pyrophosphate (copper(2+) diphosphate) the chemical species of interest is copper. As such studies referring to soluble copper ions from any source are considered to be directly relevant to Copper (II) pyrophosphate. Copper (II) pyrophosphate is considered to contribute to copper toxicity in the environment and as such the data assessment and risk assessment focusses on the copper ion as the phosphate ion is not considered to be toxic.

 

In accordance with the EU wide copper risk assessment, 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 DOC for the water compartment) and therefore copper bioavailability is considered for the interpretation of the copper effects data.

 

The high quality long term effects records used for the PNEC derivation of copper under the Existing Substances Regulation (TC NES) 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).

In a weight of evidence approach these NOECs are used for both the freshwater PNEC and the freshwater sediment PNEC derivation using the equilibrium partitioning approach. The copper threshold values derived for three high quality mesocosm studies (Hedtke, 1984; Schaefer, 2003 and Roussel, 2005 IUCLID Section 6.6.), 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.

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

Considering the importance of bioavailability for reducing the intra-species variability, the database includes information related to the development/validation of the copper bioavailability models (so called Biotic Ligand Models) and the physico-chemistry needed for the normalization of the individual NOEC values.Considering the essential functions of copper, the database further includes reliable supporting papers on copper deficiency. 

 

Marine water effects:

The marine water 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).In a weight of evidence approach these NOECs are used for both the marine water PNEC and the marine water sediment PNEC derivation using the equilibrium partitioning approach.

In response to the recommendation from TC NES and SCHER, a marine mesocosm study has been carried out (Foekema, 2010; IUCLID section 6.6). The copper threshold value derived from this high quality marine mesocosm study was used as additional WoE for the PNEC derivation.

Considering the importance of understanding the mechanism of action for defining the uncertainty around the PNEC, supportive papers are included in the database. Considering the importance of bioavailability for reducing the intra-species variability, the database includes supportive information related to the development/validation of the marine organic carbon normalization, key to copper bioavailability in marine systems. The OC normalization model is used for normalizing the NOEC/L(E) C10 values and deriving the PNEC for marine water.

 

Effects for Sewage Treatment plants:

Data on the toxicity tests performed with aquatic bacteria and protozoa, reported as L(E)C50 and 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.