Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Additional information

According to Annex VIII "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."

Furthermore, waiving 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 in the environment is an irrelevant process. Biotic processes may alter the speciation of an element, but it will not eliminate the element from the environment by degradation or transformation processes. This elemental-based assessment (i.e. pooling all speciation forms together) can be considered as a worst-case assumption for risk assessment.

The endpoints related to biodegradation in water, sediment and soil have been waived because they are not relevant for an inorganic substance. Aluminium is the most abundant metal in the lithosphere, and is characterised by a complex biogeochemical cycle, but it will only be transformed into another aluminium species and hence cannot disappear. In surface water, groundwater, or sediment, ammonia can undergo sequential transformation by two processes in the nitrogen cycle, nitrification and denitrification, which would produce ionic nitrogen compounds and, from these, elemental nitrogen. The nitrate formed will participate in one of the largest natural nutrient cycles, the nitrogen cycle, both on a local and a global scale.