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:
1990-11-07 until 1991-07-31
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: OECD Guideline study under 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 D (Ready Biodegradability: Closed Bottle Test)
Deviations:
no
GLP compliance:
yes

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): Vinyllaurat
- Physical state: colourless liquid
- Impurities (identity and concentrations):not given in report
- Composition of test material, percentage of components: as stated in substance data
- Lot/batch No.: 959837
- Stability under test conditions: stable
Specific details on test material used for the study:
Details on properties of test surrogate or analogue material (migrated information):
not applicable

Study design

Oxygen conditions:
aerobic
Inoculum or test system:
activated sludge, non-adapted
Details on inoculum:
- Source: domestic waste water treatment plant (Kläranlage Karlsruhe/Neureut 1991-02-20)
- Method of cultivation: not given in report
Duration of test (contact time):
28 d
Initial test substance concentrationopen allclose all
Initial conc.:
1 mg/L
Based on:
test mat.
Initial conc.:
2 mg/L
Based on:
test mat.
Parameter followed for biodegradation estimation
Parameter followed for biodegradation estimation:
O2 consumption
Details on study design:
TEST CONDITIONS
- Composition of medium: in accordance with Guideline
- pH adjusted: no
- Continuous darkness: yes



TEST SYSTEM
- Culturing apparatus:2 litre glass bottles
- Number of culture flasks/concentration: 2 bottles (test substance + inoculum), 2 bottles (inoculum),2 bottles (reference compound sodium acetate + inoculum), 2 bottles (test substance + reference compound sodium acetate + inoculum)
- Test substance: test substance was directly mixed with test medium


SAMPLING
- Sampling frequency: measurement was performed on exposure days 0, 5, 7, 16 and 28


CONTROL AND BLANK SYSTEM
- Inoculum blank: inoculum+ test medium
- Procedure control: soium acetate + inoculum/ test medium
- Toxicity control: test substance + sodium acetate + inoculum



Reference substance
Reference substance:
acetic acid, sodium salt

Results and discussion

Preliminary study:
not applicable
Test performance:
according to guideline
% Degradationopen allclose all
Parameter:
% degradation (O2 consumption)
Value:
0
Sampling time:
0 d
Parameter:
% degradation (O2 consumption)
Value:
74
Sampling time:
5 d
Parameter:
% degradation (O2 consumption)
Value:
87
Sampling time:
16 d
Parameter:
% degradation (O2 consumption)
Value:
98
Sampling time:
28 d
Details on results:
The reference compound sodium acetate was biodegraded by 87 % by exposure day 16 and reached an biodegradation rate of 84% by the end of the study, thus confirming suitability of the activated sludge.

BOD5 / COD results

Results with reference substance:
The reference compound sodium acetate was biodegraded by 87 % by exposure day 16 and reached an biodegradation rate of 84% by the end of the study, thus confirming suitability of the activated sludge.

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Interpretation of results:
readily biodegradable
Conclusions:
The test item Vinyl laurate is readily biodegradable under the conditions used.
Executive summary:

Vinyl laurate was investigated for its ready biodegradability in the "Closed Bottle Test" (OECD 301 D) when exposed to aerobic activated sludge from a domestic waste water treatment plant over a period of 28 days. Under the test conditions Vinyl laurate was found to be readily biodegradable over the 28-day exposure period. The reference substance sodium acetate reached the level for ready biodegradability, thus confirming suitability of the activated sludge. In the the inhibition test no inhibition of the bacterial growth was noted.