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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:
1990
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: well performed guideline study with GLP

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1991
Report Date:
1991

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 301 B (Ready Biodegradability: CO2 Evolution Test)
GLP compliance:
yes

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
purity: 98.2 %

Study design

Oxygen conditions:
aerobic
Inoculum or test system:
activated sludge, domestic (adaptation not specified)
Details on inoculum:
source: domestic waste water treatment plant Frankfurt-Sindlingen
Duration of test (contact time):
28 d
Initial test substance concentrationopen allclose all
Initial conc.:
ca. 20 mg/L
Based on:
test mat.
Initial conc.:
ca. 10 mg/L
Based on:
test mat.
Parameter followed for biodegradation estimation
Parameter followed for biodegradation estimation:
CO2 evolution
Reference substance
Reference substance:
benzoic acid, sodium salt

Results and discussion

% Degradationopen allclose all
Parameter:
% degradation (CO2 evolution)
Value:
3
Sampling time:
3 d
Parameter:
% degradation (CO2 evolution)
Value:
7
Sampling time:
7 d
Parameter:
% degradation (CO2 evolution)
Value:
10
Sampling time:
14 d
Parameter:
% degradation (CO2 evolution)
Value:
14
Sampling time:
20 d
Parameter:
% degradation (CO2 evolution)
Value:
31
Sampling time:
28 d

BOD5 / COD results

Results with reference substance:
78% degradation after 14 days
85% degradation after 20 days
94% degradation after 28 days

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Interpretation of results:
other: not readily biodegradable
Conclusions:
The substance is not readily biodegradable
Executive summary:

The substance was tested for ready biodegradability according to OECD guideline 301 B (modified Sturm test). Based on the test results and the definition of "ready biodegradability" the substance has to be considered as not readily biodegradable.