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:
07 July - 04 Aug, 1994
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: done under OECD method and GLP

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1994

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 301 D (Ready Biodegradability: Closed Bottle Test)
Qualifier:
according to
Guideline:
EU Method C.4-E (Determination of the "Ready" Biodegradability - Closed Bottle Test)
GLP compliance:
yes

Test material

Reference
Name:
Unnamed
Type:
Constituent

Study design

Oxygen conditions:
aerobic
Inoculum or test system:
activated sludge (adaptation not specified)
Details on inoculum:
A sample of activated sludge plant was kept under aerobic conditions. To prepare the inoculum, the sample was allowed to settle for 30 mins and filtered through Whatman GFA course filter paper. The first 250ml was discarded.
Duration of test (contact time):
28 d
Parameter followed for biodegradation estimation
Parameter followed for biodegradation estimation:
O2 consumption
Details on study design:
Test solns were incubated in the dark at 21±1°C and analysed for dissolved oxygen at 0, 4, 7, 11, 14, 18, 21, 25 and 28 days using a Yellow Springs BOD meteer (model 59).
Reference substance
Reference substance:
other: sodium benzoate

Results and discussion

Preliminary study:
A-88820.605 attained 0% degredation after 28 days and cannot, therefore, be termed as readily biodegadeable.
There was no evidence of inhibitory effects on the bacteria inoculum at 2mg/L.
% Degradation
Parameter:
% degradation (O2 consumption)
Value:
0
Sampling time:
28 d
Details on results:
Cultures containing both test and standard substances combined showed an oxygen depletion value 20% higher than that anticipated on the basis of results from separate culture on day 14. Consequently A-88820.605 is not considered to have had an inhibitory effect on sewage bacteria under the conditions of this test.

BOD5 / COD results

Results with reference substance:
Sodium benzoate attained 72% biodegredation after 28 days.

Any other information on results incl. tables

Oxygen depletions in the inoculated control series were ≤1.5 mg oxygen per litre after 28 days.

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Interpretation of results:
other: not readily biodegradable
Conclusions:
A-88820.605 may not be termed as readily biodegadable
Executive summary:

A-88820.605 can not be considered readily biodegadeable.

There was no evidence of inhibitory effects under the conditions of this test.