Diphosphoric acid, copper salt

Toxicity to soil microorganisms

Link to relevant study record(s)

Reference

Endpoint:

toxicity to soil microorganisms

Type of information:

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

Adequacy of study:

weight of evidence

Justification for type of information:

REPORTING FORMAT FOR THE ANALOGUE APPROACH
For further information please refer to read across justification in IUCLID section 13.

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Key result

Remarks on result:

other: Individual high quality NOEC/(L(E)C10 values from different studies range from 30 mg/kg (glucose respiration)) to 2,402 mg/kg (maize respiration).

Validity criteria fulfilled:

not applicable

Conclusions:

The effect records related to microbial processes include 77 NOEC/EC10 values: 9 different endpoints representing the C- and N-cycle and measurement of microbial biomass are available.

Description of key information

The effect records related to microbial processes include 77 NOEC/EC10 values: 9 different endpoints representing the C- and N-cycle and measurement of microbial biomass are available. The NOECs are carried forward to the risk characterisation.

Additional information

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.

 

NOECs for soil microorganisms:

The effect records related to microbial processes include 77 NOEC/EC10 values; 9 different endpoints representing the C- and N-cycle and measurement of microbial biomass are available (i.e. maize induced respiration, substrate induced respiration, litter decomposition, glutamic acid decomposition, N-mineralisation, denitrification, nitrification, ammonification, biomass C, biomass N).

Individual high quality NOEC/(L(E)C10 values from different studies range from 30 mg/kg (glucose respiration)) to 2,402 mg/kg (maize respiration).

Important intra-species variability in NOEC:L(E)C10 values are observed due to differences in the physico-chemistry of the soils. For microbial processes, 3 bio-availability models were developed: the nitrification process model, the maize respiration model (using a natural substrate) and the substrate induced respiration model (Smolder and Oorts 2004 and Oorts, 2006a). These models were used for the normalization of the NOEC data for microbial processes and the derivation of the PNEC.

Records are available on the influence of soil ageing/leaching on the plant toxicity (e.g. Chander and Brooks, 1993; Oorts 2006b). This information was used for the PNEC derivation relevant to monitoring data.

 

Additional information:

A voluntary risk assessment report of copper and copper compounds has been submitted to the European Chemicals Agency by the European Copper Institute (June 2008). This report is based on the industry initiative to perform a voluntary risk assessment on a substance according to the mechanisms of the implementation of the Existing Substance Regulation (EEC) No 793/93 (ESR). The procedure was agreed by the 11thJoint Meeting of the Competent Authorities for the Implementation of Directive 67/548/EEC and ESR Regulation. Italy has been acting as a reviewing Member State for the substance and the risk assessment report has been reviewed by the Technical Committee on New and Existing Substances (TC NES) according to standard operational procedures of the Committee.

 

In accordance with the above mentioned European copper risk assessment, the environmental hazard assessment is based on tests carried out with soluble copper species. Studies reporting quantitative dose responses of Cu(II) ions, delivered from soluble copper compounds to aquatic organisms are used for this assessment.

 

The data presented are considered to be adequate and reliable for the purpose of defining an appropriate classification for the ecotoxicity of Copper (II) pyrophosphate in accordance with Regulation (EC) No.1272/2008 (EU CLP).