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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
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2018

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
Test material form:
liquid

Study design

Oxygen conditions:
aerobic
Inoculum or test system:
activated sludge, domestic (adaptation not specified)
Duration of test (contact time):
28 d

Results and discussion

% Degradationopen allclose all
Key result
Parameter:
% degradation (CO2 evolution)
Value:
91.4
Sampling time:
28 d
Key result
Parameter:
% degradation (CO2 evolution)
Value:
68.8
Sampling time:
11 d

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Interpretation of results:
readily biodegradable
Conclusions:
All validity criteria were met.
Degradation behaviour of positive control and toxicity control was normal. Abiotic degradation was not observed. Both replicates of the test item showed good correspondence.
If degradation in the toxicity flask is below 25 % after 14 days, the test item can be consid-ered as toxic towards the inoculum. As degradation in the toxicity flask was 80.9 % after 14 days, the test item can be stated as “not toxic towards the inoculum in a concentration of 24.8 mg/L”.
Ready biodegradability is defined in the guidelines as degradation surpassing 60% within 10 days after reaching a level of 10 %. The 10-day-window began on day 4, at its end, 79 % (graphic evaluation), degradation was reached, surpassing the pass level of 60 % given in the OECD guideline. Therefore, the test item [3R-(3α, 3aβ,6α,7β,8aα)]-octahydro-3,6,8,8-tetramethyl-1H-3a,7-methanoazulen-6-ol (Cedrol) can be considered as “readily biodegradable”.
No observations were made which might cause doubts concerning the validity of the study outcome.
The result of the test can be considered valid.