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
Study period:
May 29 -June 26, 2002
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Remarks:
Reliability 1

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2002
Report Date:
2002

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
EU Method C.4-D (Determination of the "Ready" Biodegradability - Manometric Respirometry Test)
Version / remarks:
1992
Qualifier:
according to
Guideline:
OECD Guideline 301 F (Ready Biodegradability: Manometric Respirometry Test)
Version / remarks:
1992
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:
The activated sludge used for this study was washed by centrifugation and the supernatant liquid phase was decanted. The solid material was resuspended in tap water and again centrifuged. This procedure was repeated twice. An aliquot of the final sludge suspension was weighed, dried and the ratio of wet sludge to its dry weight was determined. Based on this ratio, calculated aliquots of washed sludge suspension, corresponding to 1.5 g dry material per litre were mixed with test water and then aerated until use.
Duration of test (contact time):
28 d
Initial test substance concentrationopen allclose all
Initial conc.:
100 mg/L
Based on:
test mat.
Initial conc.:
102.4 mg/L
Based on:
test mat.
Parameter followed for biodegradation estimation
Parameter followed for biodegradation estimation:
O2 consumption
Details on study design:
OECD TG 301 F
Reference substance
Reference substance:
aniline
Remarks:
25.1 mg/L

Results and discussion

% Degradation
Key result
Parameter:
% degradation (O2 consumption)
Value:
>= -4 - <= -3
Sampling time:
28 d
Details on results:
Points of degradation plot (test substance): >=-4 to <=-3% degradation after 28 d

BOD5 / COD results

Results with reference substance:
Points of degradation plot (reference substance): 85% degradation after 14 d, 93% degradation after 28 d

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Interpretation of results:
not readily biodegradable
Conclusions:
The degradation rate of the test material did not reach 60 % within the 10-day window and after 28 days of incubation. The test item can therefore be considered to be not readily biodegradable.