Registration Dossier

Environmental fate & pathways

Biodegradation in water: screening tests

Currently viewing:

Administrative data

Link to relevant study record(s)

Description of key information

The sodium salt is not readily biodegradable, based on 0 % degradation in 28d (OECD 301 E)

Key value for chemical safety assessment

Additional information

The study was conducted according to an appropriate OECD test guideline and in compliance with GLP.

This substance is a member of a category of various ionised forms of the acid ATMP (CAS 6419-19-8). The main assumption is that ammonium is not significant in respect of all the properties under consideration. In dilute aqueous conditions of defined pH a phosphonate ion will behave no differently to the parent acid, at identical concentration of the particular speciated form present and will be fully dissociated. Hence some properties (measured or expressed in aqueous media, e.g. ecotoxicity) for a salt can be directly read across (with suitable mass correction) to the parent acid and vice versa. Exposure of the soil would only be expected to occur via some form of aqueous processing (e.g. from spreading of WWTP sewage sludge). Thus it is acceptable to additionally read across between the parent acid and salts for the soil compartment. In the present context the effect of the counter-ion (potassium) will not be significant. In biological systems and the environment, polyvalent metal ions will be present, and the phosphonate ions show very strong affinity to them.

The ammonium ion upon release into the environment would enter natural nitrogen cycles in air, soil and water.