Registration Dossier

Environmental fate & pathways

Biodegradation in water: screening tests

Administrative data

Endpoint:
biodegradation in water: screening tests
Type of information:
migrated information: read-across from supporting substance (structural analogue or surrogate)
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: see 'Remark'
Remarks:
The structure of iron ore pellets consists essentially of iron oxide grains. The bonding of the grains occur by oxide bridging, recrystallisation of hematite and to a lesser extent by the formation of fused silicate phases. Since silicates are inert and no effect on the environment is expected, the endpoints in Chapters 5 and 6 are based on the effects of iron as a worst case in these substances. More information on the justification of read across can be found in the attached document in the endpoint summaries of section 5 and 6.
Data waiving:
study scientifically not necessary / other information available
Justification for data waiving:
other:

Data source

Materials and methods

Results and discussion

Applicant's summary and conclusion

Conclusions:
Annex VIII states that "Further degradation testing shall be considered if the chemical safety assessment according to Annex I indicates the need to investigate further the degradation of the substance. The choice of the appropriate test(s) will depend on the results of the chemical safety assessment. "Waiving of the need for data for this endpoint in the aquatic compartment may be considered if “the substance is highly insoluble in water”, or if “the substance is readily biodegradable” (ECHA 2008, Chapter R.7B – Endpoint Specific Guidance). However, for an inorganic substance for which the chemical assessment is based on the elemental concentration (i.e., pooling all inorganic speciation forms together), biotic degradation is an irrelevant process: biotic processes may alter the speciation form of an element, but it will not eliminate the element from the aquatic compartment by degradation or transformation. This elemental-based assessment (pooling all speciation forms together) can be considered as a worst-case assumption for the chemical assessment.