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
Reliability:
1 (reliable without restriction)

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2000
Report Date:
2000

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 301 F (Ready Biodegradability: Manometric Respirometry Test)
Deviations:
no
Qualifier:
according to
Guideline:
EU Method C.4-D (Determination of the "Ready" Biodegradability - Manometric Respirometry Test)
Deviations:
no
GLP compliance:
yes (incl. certificate)

Test material

Reference
Name:
Unnamed
Type:
Constituent

Study design

Oxygen conditions:
aerobic
Inoculum or test system:
activated sludge (adaptation not specified)
Details on inoculum:
- Source of inoculum/activated sludge

Stain/Inoculation: Mixture of polyvalent bacteria (activated sludge) collected from the aeration tank of a domestic sewage plant,
PRO RHENO Basel communal.

Pre-treatment: The activated sludge was washed 4 times with tap water and the last time with test medium.
A sample of the activated sludge was taken to determine the dry weight of the Suspended Solids (SS).
An amount corresponding to 2 – 3 g per lyre of suspended solids was mixed with test medium.
The pre-treated sludge was aerated until use.

Bacterial concentration: 30 mg/L suspended solids.
The bacterial concentration was obtained by adding 10 ml of the pre-treated sludge (3.0 g/L SS) per 100 ml test medium.
Duration of test (contact time):
ca. 28 d
Initial test substance concentration
Initial conc.:
ca. 30 mg/L
Based on:
other: suspended solids
Parameter followed for biodegradation estimation
Parameter followed for biodegradation estimation:
O2 consumption
Details on study design:
TEST CONDITIONS
- Composition of medium:
The mineral salts for each of the following stock solutions were dissolved in 1 litre of distilled water.

Stock solution A: 8.5 g of potassium dihydrogen phosphate, 21.7 5 g of di-potassium hydrogen phosphate,
33.4 g of di-sodium hydrogen phosphate dehydrate and 0.5 g of ammonium chloride.
The pH value of this solution was 7.4.

Stock solution B: 36.4 g of calcium chloride dehydrate.

Stock solution C: 22.5 g of magnesium sulphate heptahydrate.

Stock solution D: 0.25 g ferric chloride hexahydrate

10 ml of solution A and 1 ml of solutions B, C and D were added per 1 litre distilled water to form the test medium.

- Test temperature: 22 – 23 °C
- pH ofTest medium: Stock solution A = 7.4
- pH adjusted: no
- Suspended solids concentration: 30 mg/L
- Continuous darkness: yes
- Stock solutions and test concentrations:
Stock solution: 2.5 g/500 ml reference item on distilled water.

Test concentrations: 100 mg/L of the reference item (20 ml stock solution in 1000 ml test medium).
100 mg/L of the test item.
Because the test item was not completely soluble in the test medium it was given directly into the
test system without preparation of a stock solution.

Directly weighing: 24.9 mg test item/250 ml test medium in vessel. 13
24.9 mg test item/250 ml test medium in vessel. 14
25.1 mg test item/250 ml test medium in vessel. 15
25.2 mg test item/250 ml test medium in vessel. 16

CONTROL AND BLANK SYSTEM
- Test item: 2 vessels with inoculum + test medium + test item.
- Inoculum control: 1 vessel with inoculum + test medium.
- Reference control: 2 vessels with inoculum + test medium + a readily biodegradable reference compound.
- Abiotic control: 1 vesel with test medium + test item + sterilising agent.
- Toxicity control: 1 vessel with inoculum + test medium + test item + a readily biodegradable reference compound.


DATA REPORTING
The oxygen consumption was automatically measured by the test apparatus. The selected measuring range was x 1, (250 ml test medium per vessel). The oxygen consumption was given in milligrams oxygen per litre.
Reference substance
Reference substance:
benzoic acid, sodium salt

Results and discussion

% Degradation
Parameter:
other: biodegradation
Value:
ca. 1
Sampling time:
28 d
Details on results:
Test item: Biodegradation after 28 days 1 %
Reference item: Biodegradation after 14 days 78 %
Toxicity control: Biodegradation after 14 days 47 %
Abiotic control: Biodegradation after 28 days 0 %

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Interpretation of results:
other: not readily biodegradable after 28 days of incubation
Conclusions:
The test item CA 2814 B (Intermediate to CGA 276854) was not readily biodegradable after 28 days of incubation.
Executive summary:

Findings:

Test item Biodegredation after 28 days 1 %

Reference item Biodegradation after 14 days 78 %

Conclusion:

The test item CA 2814 B (Intermediate to CGA 276854) was not readily biodegradable after 28 days of incubation.