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 key study indicates that L-phenylalanine is readily biodegradable.  

The supporting studies also indicate that L-phenylalanine is readily biodegradable.

Key value for chemical safety assessment

Biodegradation in water:
readily biodegradable

Additional information

A study with DL-phenylalanine indicates that L-phenylalanine is readily biodegradable. DL-phenylalanine is rapidly oxidized in activated sludge. After only 24 h already more than 16% of the Theoretical Oxygen Demand were achieved. Read-across from DL-phenylalanine to L-phenylalanine was applied because of similar physico-chemical characteristics, a similar toxicological/ecotoxicological profile and the structural similarity of racemic phenylalanine to the enantiomer L-phenylalanine. One can expect that the equivalent concentrations of L-phenylalanine will also be rapidly oxidised in activated sludge. Instead of DL-phenylalanine, L-phenylalanine is a natural constituent of most living cells, is involved in many metabolic pathways and more subject to undergo biodegradation.

The study was considered the most reliable one in comparison to the other applicable studies. Thus, it was chosen as the key study.

The other supporting studies were considered to be less reliable, because their documentation was insufficient. The experimental results of these three supporting studies also consistently indicate that L-phenylalanine is readily biodegradable.