Registration Dossier

Diss Factsheets

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:
1999/05/11 - 1999/07/21
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

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

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to guideline
Guideline:
EU Method C.4-E (Determination of the "Ready" Biodegradability - Closed Bottle Test)
Version / remarks:
29 December 1992
Deviations:
no
Qualifier:
according to guideline
Guideline:
OECD Guideline 301 D (Ready Biodegradability: Closed Bottle Test)
Version / remarks:
adopted 17 July 1992
Deviations:
no
GLP compliance:
yes (incl. QA statement)

Test material

Constituent 1
Chemical structure
Reference substance name:
1,3-dihydroxyacetone
EC Number:
202-494-5
EC Name:
1,3-dihydroxyacetone
Cas Number:
96-26-4
Molecular formula:
C3H6O3
IUPAC Name:
1,3-dihydroxyacetone
Details on test material:

Purity: 99.5 %

Study design

Oxygen conditions:
aerobic
Inoculum or test system:
activated sludge, industrial, non-adapted
Details on inoculum:
- Source of inoculum/activated sludge: Effluent of an activated sludge plant which is operated with a mixed waste water (industrial and municipal) of Merck KGaA, Darmstadt, Germany
- Method of cultivation: Aeration over 5 days
- Storage length: 5 days
- Preparation of inoculum for exposure: Filtration (coarse filter)
- Concentration of sludge: 5 mL/L
- Initial cell/biomass concentration:
- Water filtered: yes
- Type and size of filter used, if any: coarse folded paper filter
Duration of test (contact time):
28 d
Initial test substance concentration
Initial conc.:
4 mg/L
Based on:
test mat.
Parameter followed for biodegradation estimation
Parameter followed for biodegradation estimation:
O2 consumption
Details on study design:
Accordung to guideline
Reference substance
Reference substance:
aniline

Results and discussion

Test performance:
According to guideline
% Degradationopen allclose all
Key result
Parameter:
% degradation (O2 consumption)
Value:
67
Sampling time:
7 d
Key result
Parameter:
% degradation (O2 consumption)
Value:
74
Sampling time:
14 d
Key result
Parameter:
% degradation (O2 consumption)
Value:
77
Sampling time:
28 d
Remarks on result:
other: 10-day window passed
Details on results:
Duration of the experiment: 28d
Temperature: 20 +/- 1 DEG

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Interpretation of results:
readily biodegradable
Conclusions:
The test material was readily biodegradable under the described conditions of this study.
Executive summary:

In this study, the test item was assessed for its possible biodegradation. For this purpose a screening for ready biodegradability in an aerobic aqueous medium was performed at a concentration of 4 mg/L. The study design follows the conditions as described in the OECD Guideline for testing of chemicals 301D (Closed bottle method).

After 28d, the reference substance (Aniline) shows full degradation suggesting the validity of the experimental setup. For the test item, a degradation of 67% and 77% was obtained after 7 and 28 days, respectively. These experimental values indicate that the test substance is ready biodegradable under the conditions of this experiment.