Registration Dossier

Environmental fate & pathways

Biodegradation in water: screening tests

Currently viewing:

Administrative data

Link to relevant study record(s)

Referenceopen allclose all

Endpoint:
biodegradation in water: ready biodegradability
Type of information:
experimental study
Adequacy of study:
key study
Study period:
1985/11/22 - 20/12/1986
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: OECD guideline study, study was conducted under GLP like quality assurance.
Qualifier:
according to
Guideline:
OECD Guideline 301 B (Ready Biodegradability: CO2 Evolution Test)
Deviations:
no
GLP compliance:
no
Remarks:
but GLP like quality assurance
Oxygen conditions:
aerobic
Inoculum or test system:
activated sludge, non-adapted
Details on inoculum:
- Source of inoculum/activated sludge:
Bacteria collected from activated sludge of the sewage treatment plant of CH-4153 Reinach on 19/11/85. The preparation was carried out according to the method described in the guideline.
Duration of test (contact time):
28 d
Initial conc.:
10 mg/L
Based on:
test mat.
Initial conc.:
20 mg/L
Based on:
test mat.
Parameter followed for biodegradation estimation:
CO2 evolution
Details on study design:
TEST CONDITIONS
- Composition of medium:The test medium was prepared according to the method described in the guideline.
- Test temperature: 22 + or - 2 degrees
- Aeration of dilution water: Approx. 50 mL/min free of carbon dioxide.

TEST SYSTEM
- Culturing apparatus: 2 liters flasks equipped with gas inlet and magnetic stirrer.
- Number of culture flasks/concentration: 1

SAMPLING
- Sampling frequency: day 4 / 7 / 10 / 13 / 17 / 24 / 27 and 28
Reference substance:
aniline
Parameter:
% degradation (CO2 evolution)
Value:
13
Sampling time:
28 d
Remarks on result:
other: 20 mg/L test substance
Parameter:
% degradation (CO2 evolution)
Value:
19
Sampling time:
28 d
Remarks on result:
other: 10 mg/L test substance
Details on results:
The test item is not is not biodegradable in this test.
The biodegradation of the reference substances was calculated as 91 % in 28 days
Interpretation of results:
other: not readily biodegradable
Endpoint:
biodegradation in water: screening tests
Type of information:
experimental study
Adequacy of study:
supporting study
Study period:
1986-02-11
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Guideline study, study was performed predated GLP.
Qualifier:
equivalent or similar to
Guideline:
other: "Deutsche Einheitsverfahren zur Wasseruntersuchung" H 41 December 1980 DIN 38 409
Principles of method if other than guideline:
Determination of the chemical oxygen demand by oxydation of the test substance with potassium dichromate.
GLP compliance:
no
Remarks:
but GLP like quality assurance
Oxygen conditions:
other: not relevant
Inoculum or test system:
other: not applicable
Duration of test (contact time):
2 h
Details on study design:
TEST CONDITIONS
- Test temperature: 148 +/- 3 degrees.
Reference substance:
other: Potassium hydrogen phthalate
Parameter:
COD
Value:
2.15 g O2/g test mat.
Results with reference substance:
Reference substance : 201 mg COD/L (limit: 192 - 208 mg COD/L)

Result: 2.15 g O2/g test item

Description of key information

Not readily biodegradable (according to OECD criteria).

Key value for chemical safety assessment

Additional information

According to the key study (CIBA, 1986) the ready biodegradability of the test item was assessed over a 28 day period by the modified Sturm test (OECD 301B). The nominal test concentrations were 10 and 20 mg a.s./L. The test material attained up to 13 and 19 % biodegradation after 28 days whereas the positive control substance (Aniline) was 94.4 % degraded 28 days. These results indicate that the test item cannot be classified readily biodegradable under conditions of the test. In a supportive study (Ciba, 1986) the Chemical Oxygen Demand was determined. After an exposure of 2 h the amount of O2 was very low, indicating no degradation of the test item.