Registration Dossier

Environmental fate & pathways

Biodegradation in water: screening tests

Administrative data

Endpoint:
biodegradation in water: ready biodegradability
Type of information:
other: expert statement
Adequacy of study:
weight of evidence
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: expert statement

Data source

Referenceopen allclose all

Reference Type:
publication
Title:
Unnamed
Year:
1996
Reference Type:
publication
Title:
Effect of copper on nitrifying and heterotrophic populations in activated sludge
Author:
Song J., Cha D., Allen H., Son A., Choe J.
Year:
2002
Bibliographic source:
Proceedings of the Water Environment Federation, WEFTEC 2002: Session 41 through Session 50, pp. 357-366(10).
Reference Type:
study report
Title:
Unnamed
Year:
2005

Materials and methods

Test guideline
Qualifier:
no guideline followed
Principles of method if other than guideline:
Litterature review.
Estimation of the Cu2+ inhibitory activity towards STP microbes as a worst-case estimation of the test item ready biodegradability.
see more details under results.
GLP compliance:
no
Remarks:
not applicable to expert statement

Test material

Reference
Name:
Unnamed
Type:
Constituent
Specific details on test material used for the study:
not applicable to expert statement

Study design

Inoculum or test system:
other: not applicable to expert statement

Results and discussion

% Degradation
Key result
Parameter:
probability of ready biodegradability (QSAR/QSPR)
Remarks on result:
not readily biodegradable based on QSAR/QSPR prediction
Remarks:
see results
Details on results:
see below

Any other information on results incl. tables

The test item consists in an organic part (L-pidolic acid, CAS 98 -79 -3) and the Cu2 + ion. The organic part L-Pidolic acid is readily biodegradable (lead registrant proprietary data: Barthel Y, 2005). But the Cu2+ ion has a strong inhibitory activity towards microbe activity, as reflected in Madoni et al. (1996) and Song et al. (2002) publications.

The Cu2+ supply at the recommended dose-level of a biodegradation test on Copper Pidolate (CuPCA), 100 mg/L according to OECD 301, would be: 100*MW(Cu)/MW(CuPCA)= 100*63.55/319.76 = 19.9 mg/L.

This is largely above all Cu2+ concentrations reported as inhibitory to microbes in the two publications.

Therefore, as a worst-case the test item is considered as non-readily biodegradable without need for testing.

Applicant's summary and conclusion

Validity criteria fulfilled:
not applicable
Interpretation of results:
not readily biodegradable
Conclusions:
As a worst-case the test item is considered as non-readily biodegradable without need for testing.