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:
1999-11-17 to 1999-12-08
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Guideline study, GLP.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1999
Report Date:
1999

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 301 A (Ready Biodegradability: DOC Die Away Test)
GLP compliance:
yes

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): Adipic acid, Cyclic ester with diethylenglycol
- Analytical purity: > 90%
- Impurities (identity and concentrations): Diethylenglycol <10% ; water<2%
- Purity test date: Report of the sponsor of Jan 1999
- Lot/batch No.: B47

Study design

Oxygen conditions:
aerobic
Inoculum or test system:
activated sludge, domestic, non-adapted
Details on inoculum:
- Source of inoculum/activated sludge (e.g. location, sampling depth, contamination history, procedure): Laboratory wastewater plants treating municipal and synthetic sewage
- Preparation of inoculum for exposure: Inoculum was pre-aerated two days before the start of the test
- Initial cell/biomass concentration: 30 mg/L dry substance
Duration of test (contact time):
21 d
Initial test substance concentrationopen allclose all
Initial conc.:
37 mg/L
Based on:
test mat.
Initial conc.:
20 mg/L
Based on:
DOC
Parameter followed for biodegradation estimation
Parameter followed for biodegradation estimation:
DOC removal
Details on study design:
TEST CONDITIONS
- Test temperature: room temperature

TEST SYSTEM
- Culturing apparatus: batch system, 1 L total test volume
- Number of culture flasks/concentration: 2
- Test performed in open system: yes

SAMPLING
- Sampling frequency: every 1-3 days

CONTROL AND BLANK SYSTEM
- Inoculum blank: yes
- Abiotic sterile control: yes
- Toxicity control: yes
- Other: in addition an inhibition control and adsorption control was tested in parallel
Reference substance
Reference substance:
aniline

Results and discussion

% Degradationopen allclose all
Parameter:
% degradation (DOC removal)
Value:
1
Sampling time:
1 d
Parameter:
% degradation (DOC removal)
Value:
17
Sampling time:
3 d
Parameter:
% degradation (DOC removal)
Value:
61
Sampling time:
5 d
Parameter:
% degradation (DOC removal)
Value:
87
Sampling time:
10 d
Parameter:
% degradation (DOC removal)
Value:
100
Sampling time:
14 d

BOD5 / COD results

Results with reference substance:
DOC-decrease of reference control:
1 day: 3%
3 days: 22%
5 days: 97%

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Remarks:
1) Degradation degree of the test substance >70% within 28 days: yes; 2) 10-day window met: yes; 3) No pre-adapted inoculum used: yes
Interpretation of results:
readily biodegradable