Registration Dossier

Data platform availability banner - registered substances factsheets

Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Environmental fate & pathways

Biodegradation in water: screening tests

Currently viewing:

Administrative data

Link to relevant study record(s)

Description of key information

Uronium hydrogen sulphate readily degrades to urea and sulfuric acid and/or sulfate ions in the environment.
Urea is considered to be readily biodegradable.
Sulfates (e.g. calcium sulphate) are inorganic substances and therefore will not undergo biodegradation i.e. microbial degradation to carbon dioxide and water, since they don’t contain any carbon or hydrogen atoms in their chemical formula. Sulfates will therefore undergo dissociation into sulfate ions and cations (e.g. Ca2+) only.

Key value for chemical safety assessment

Biodegradation in water:
readily biodegradable

Additional information

The degradation of urea was investigated in psychrophilic bacteria in an aqueous test system. The maximum degradation rate per hour at 20C was 11.6 mg/L. The average degradation rate per hour at 20C was 10.9 mg/L. The maximum degradation rate per hour at 2C was 4.0 mg/L. The average degradation rate per hour at 2C was 3.2 mg/L.

The biodegradation of urea was investigated in activated sludge from a laboratory sewage treatment facility fed with adapted domestic and synthetic sewage. Degradation levels of 3% (3 hours), 52% (7 hours), 60% (10 days), 85% (14 days) and 96% (16 days) was seen. Urea is ultimately biodegradable according to this study.

The biodegradation of dimethyl urea was investigated in a DOC-die away study. The biodegradation (DOC removal) after 21 days is 90-100%. Dimethyl urea is therefore readily biodegradable according to OECD criteria. The degree of degradation of the reference substance was 100% after 21 day and the degradation degree in inhibition control was 101%. The validity criteria is therefore met according to OECD criteria.