Registration Dossier

Environmental fate & pathways

Biodegradation in water: screening tests

Administrative data

Endpoint:
biodegradation in water: ready biodegradability
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2003
Report Date:
2003

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
EU Method C.4-A (Determination of the "Ready" Biodegradability - Dissolved Organic Carbon (DOC) Die-Away Test)
Qualifier:
according to
Guideline:
OECD Guideline 301 A (Ready Biodegradability: DOC Die Away Test)
GLP compliance:
yes (incl. certificate)

Test material

Reference
Name:
Unnamed
Type:
Constituent

Study design

Oxygen conditions:
aerobic
Inoculum or test system:
activated sludge, domestic (adaptation not specified)
Details on inoculum:
- content of suspended solids in test batches: 29.6 mg/L
- content of dry matter in the inoculum: 4930 mg/L

Duration of test (contact time):
28 d
Initial test substance concentration
Initial conc.:
15.99 mg/L
Based on:
DOC
Details on study design:
TEST CONDITIONS
- Test temperature: 21.0-21.1°C
- pH: 7.6

TEST SYSTEM
- Culturing apparatus: 2000 mL glass vessels
- Number of culture flasks/concentration: 2 flasks containing test item and inoculum
2 flasks without test item, but with inoculum (=blank batches).
2 flasks containing reference item (Sodium benzoate) and inoculum (=reference batches).
- Measuring equipment: Infrared analyser T 5000 A (Shimadzu)

SAMPLING
- Sampling frequency: 0 and 3 hours, 7, 14, 21, 27 and 28 days
Reference substance
Reference substance:
benzoic acid, sodium salt

Results and discussion

% Degradation
Parameter:
% degradation (DOC removal)
Value:
< 0
Sampling time:
28 d
Details on results:
Kinetic of test substance (in %):
= 0 after 7 day(s)
< 0 after 14 day(s)
< 0 after 21 day(s)
< 0 after 27 day(s)
< 0 after 28 day(s)
Kinetic of control substance (in %):
> 100 after 14 day(s)
> 100 after 28 day(s)

Applicant's summary and conclusion

Interpretation of results:
not readily biodegradable