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Environmental fate & pathways

Biodegradation in water and sediment: simulation tests

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Administrative data

Endpoint:
biodegradation in water: sewage treatment simulation testing
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: see 'Remark'
Remarks:
This experiment is issued from a publication testing the biodegradability of catechol in several different tests. All of them showed uniform results concluding catechol is well biodegraded. This consistency of the results reinforce the reliability of the global publication. The present experiment is relatively well described, with the restriction that the purity of catechol is not mentioned.

Data source

Reference
Reference Type:
publication
Title:
A correlation study of biodegradability determinations with various chemicals in various tests.
Author:
Gerike P., Fischer W.K.
Year:
1979
Bibliographic source:
Ecotoxicol. Environ. Saf., 3, 159-173.

Materials and methods

Test guideline
Qualifier:
equivalent or similar to guideline
Guideline:
OECD Guideline 303 A (Simulation Test - Aerobic Sewage Treatment. A: Activated Sludge Units)
Deviations:
not specified
GLP compliance:
no

Test material

Constituent 1
Chemical structure
Reference substance name:
Pyrocatechol
EC Number:
204-427-5
EC Name:
Pyrocatechol
Cas Number:
120-80-9
Molecular formula:
C6H6O2
IUPAC Name:
pyrocatechol
Details on test material:
no data
Radiolabelling:
not specified

Study design

Oxygen conditions:
aerobic
Inoculum or test system:
other: communal sewage treatment plant (non adapted)
Details on source and properties of surface water:
No data
Details on inoculum:
The test was started with 2.5 g/l of dry matter of sludge from a communal sewage treatment plant.
No further data.
Initial test substance concentration
Initial conc.:
>= 12 mg/L
Based on:
test mat.
Parameter followed for biodegradation estimation:
DOC removal
Details on study design:
The test was performed under steady-state conditions, i.e. as a continuous flow system, and to employ an organic base medium, i.e. to maintain nutrient competition at all times.

Results and discussion

% Degradation
% Degr.:
98
St. dev.:
4
Parameter:
DOC removal
Sampling time:
0 d
Remarks on result:
other: sampling in the "working-in time"
Transformation products:
not measured

Applicant's summary and conclusion

Validity criteria
Validity criteria fulfilled:
not specified
Conclusions:
Catechol is biodegradable under the tested conditions.
Executive summary:

In a study (Gericke, 1979), the biodegradability of the substance Catechol (unknown purity, initial concentration >= 12 mg/L), was tested in a coupled units simulation test, according to OECD guideline 303A.

Inoculum used in this study was  2.5 g/l of dry matter of non adapted sludge from a communal sewage treatment plant.

The percentage of biodegradation was estimated by following the DOC removal.

The corresponding percentage of biodegradation obtained was 98% of DOC removal after a working-in time of 0 day.

Under the test conditions, Catechol is considered as biodegradable.