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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:
2002-07-16 until 2002-09-26
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Good laboratory practice guideline study (OECD).

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2008
Report date:
2008

Materials and methods

Test guideline
Qualifier:
according to guideline
Guideline:
OECD Guideline 301 F (Ready Biodegradability: Manometric Respirometry Test)
Deviations:
no
GLP compliance:
yes (incl. QA statement)

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): (S)-Pentan-2-ol
- Substance type: intermediate
- Physical state: liquid
- Stability under test conditions: pure: stable until 2008-09-30,
in Water: stable under test conditions
- Storage condition of test material: room temperature in the dark
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 of inoculum/activated sludge (e.g. location, sampling depth, contamination history, procedure): sewage plant Darmstadt, Germany
- Preparation of inoculum for exposure: Washing by centrifugation and supernatant phase was decanted. Solid material was resuspended and again centrifuged. This procedure was repeated twice.
- Pretreatment: not applicable
- Concentration of sludge: 1.5 g dry material per litre
Duration of test (contact time):
28 d
Initial test substance concentration
Initial conc.:
100 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: a) buffer KH2PO4, K2HPO4, Na2HPO4, NH4Cl ; b) Mg2SO4 x 7 H2O ; c) CaCl2 x 2 H2O ; FeCl3 x 6 H2O
- Test temperature: 22 °C
- pH: 7.6
- pH adjusted:no
- Suspended solids concentration: 30 mg per litre
- Continuous darkness: yes

TEST SYSTEM
- Number of culture flasks/concentration: 2
- Measuring equipment: nanometric (BSB/BOD-Sensor-System Aqualytic)
- Test performed in closed vessels due to significant volatility of test substance: no
- Test performed in open system: yes


CONTROL AND BLANK SYSTEM
- Inoculum blank: yes
- Abiotic sterile control: yes (test water)
- Toxicity control: yes (Sodium benzoate and test substance)
- Other: procedure control (Sodium benzoate)
Reference substance
Reference substance:
benzoic acid, sodium salt

Results and discussion

% Degradation
Parameter:
% degradation (O2 consumption)
Value:
>= 93 - <= 94
Sampling time:
28 d
Details on results:
Toxicity control, procedure control, inorganic control worked as expected.

BOD5 / COD results

Results with reference substance:
96% biodegradation after 28 days

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Interpretation of results:
readily biodegradable
Conclusions:
The substance is readily biodegradable.
Executive summary:

The test substance was readily biodegradable in a manometric respiratory test performed according to OECD guideline 301F showing a degradation of 93 and 94% after 28 days.