Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Biodegradation in water: screening tests:

- published data: sufficiently documented non-GLP, non-guideline study, RL2, exposure of the test item (500 mg/L) to activated sludge solids at 2500 mg/L in the Warburg respirometer, measurement of oxygen uptake, oxygen uptake in %: 24.7 within 24h, readily biodegradable

- QSAR prediction with the Estimation Programs Interface (EPI) SuiteTM v4.1 containing BIOWIN models 1 -7 (v4.1), RL2, substance falls within the applicability domain, readily biodegradable

Hydrolysis:

- not necessary because the substance is readily biodegradable

Adsorption/desorption:

- no test necessary: the substance exhibits a low logKow (-3.82) and therefore adsorption is not expected.

Additional information

For the assessment of biodegradability of L-asparagine are no GLP and OECD compliant studies available. There is one publication with sufficient documentation conducted with scientifically accepted methods that is regarded acceptable for assessment.

In a published study of Malaney and Gerhold the biological oxygen demand, i.e. the concentration of oxygen in mg/L required to oxidize 500 mg/L of substrate completely, of activated sludge incubated with L-asparagine was determined. The result reveals that 24.7 % of the compound were degraded within 24 h, therefore L-asparagine is considered to be readily biodegradable.

The result reveals that 24.7 % of the compound were degraded within 24 h, indicating that L-asparagine can be considered to be readily biodegradable. The very good biodegradability was forseeable as the substance is a natural constituent of living cells and is involved in many metabolic pathways. More, many microorganisms use the substance as carbon and nitrogen source for growth.

Additionally, a QSAR estimation was performed with the Estimation Programs Interface (EPI) SuiteTM v4.1 containing BIOWIN models 1 -7 (v4.1). The substance is predicted to be readily biodegradable supporting the experimental data.