Diphosphoric acid, copper salt

Biodegradation in water and sediment: simulation tests

Link to relevant study record(s)

Reference

Endpoint:

biodegradation in water: simulation testing on ultimate degradation in surface water

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

other:

Transformation products:

not specified

Description of key information

No studies for the endpoint 'further biotic degradation' were performed for the following reasons: The mode of degradation for copper (II) pyrophosphate is not relevant as the substance will dissociate to the cation and anion. The cation cannot be further degraded and the the pyrophosphate anion will be rapidly degraded to orthophosphate. The orthophosphate anion has no potential mechanism for further hydrolysis or degradation as it is the final common hydrolysis product of higher polyphosphates.  This was recognised in the Guidance to Regulation (EC) No 1272/2008 Classification, Labelling and Packaging of substances and mixtures ( metals annex): “Environmental transformation of one species of a metal to another species of the same does not constitute degradation as applied to organic compounds and may increase or decrease the availability and bioavailability of the toxic species. However as a result of naturally occurring geochemical processes metal ions can partition from the water column. Data on water column residence time, the processes involved at the water – sediment interface (i.e. deposition and re-mobilisation) are fairly extensive, but have not been integrated into a meaningful database. Nevertheless, using the principles and assumptions discussed above in Section IV.1, it may be possible to incorporate this approach into classification.  "  As such the environmental transformation of copper is discussed under the endpoint ‘additional information on environmental fate’.