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:
read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
key study
Justification for type of information:
Please refer to the category approach justification provided in section 13.
Reason / purpose:
read-across source
Parameter:
% degradation (O2 consumption)
Value:
87
Sampling time:
28 d
Remarks on result:
other:
Remarks:
Source, key, 5274-61-3, BASF, 1997, R 9700842, act. sludge, 28 d, RL2
Interpretation of results:
readily biodegradable
Conclusions:
The substance is readily biodegradable according to OECD guideline 301 F. The 10 -day window was passed. 62% biodegradation was reached at the end of the 10 -day window.
Endpoint:
biodegradation in water: ready biodegradability
Type of information:
experimental study
Adequacy of study:
key study
Study period:
03 - 31 Jul 1997
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: GLP - Guideline study but lack of data and incomplete description of the study design
Qualifier:
according to
Guideline:
EU Method C.4-D (Determination of the "Ready" Biodegradability - Manometric Respirometry Test)
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 301 F (Ready Biodegradability: Manometric Respirometry Test)
GLP compliance:
yes
Remarks:
including statement of compliance from laboratory head
Oxygen conditions:
aerobic
Inoculum or test system:
activated sludge, domestic, non-adapted
Details on inoculum:
- Source of inoculum/activated sludge: sewage plant, Hochdahl, Germany
- Concentration of sludge: 100 ml sludge/L medium
Duration of test (contact time):
28 d
Initial conc.:
100 mg/L
Based on:
test mat.
Parameter followed for biodegradation estimation:
O2 consumption
Details on study design:
TEST CONDITIONS
- Test temperature: 22 ± 1 °C

TEST SYSTEM
- Number of culture flasks/concentration: 3
- Details of trap for CO2 and volatile organics if used: soda lime was used to trap CO2

SAMPLING
- Sampling frequency: every day

CONTROL AND BLANK SYSTEM
- Inoculum blank: 3
- Toxicity control: 3

Reference substance:
acetic acid, sodium salt
Remarks:
ThOD: 470 mg O2/g (calculated from chemical formula)
Parameter:
% degradation (O2 consumption)
Value:
87
Sampling time:
28 d
Details on results:
ThOD: 2807 mg O2/g
Results with reference substance:
88% biodegradation of the reference substance occured after 14 days and 91% after 28 days.

10 -day window was passed. 62% biodegradation was reached at the end of the 10 -day window.

Interpretation of results:
readily biodegradable

Description of key information

Readily biodegradable: 87% (O2 consumption) in 28 days (OECD 301F)

Key value for chemical safety assessment

Biodegradation in water:
readily biodegradable
Type of water:
freshwater

Additional information

For alcohol ethoxylates C16, <2.5EO (CAS 9004-95-9) the biodegradability was assessed on the basis of an experimental study of a structural analogue substance (diethylenglycol – hexadecylether, C16E2, CAS 5274-61-3) (BASF, 1997). The study was performed according to the EU method C.4-D (corresponds to OECD guideline 301 F) and GLP. A non-adapted, activated sludge from a domestic sewage treatment plant was used as inoculum and was exposed to an initial test substance concentration of 100 mg/L. After 28 d, 87% degradation of the test substance (according to O2 consumption) was observed. The 10-day window criterion was passed as 62% biodegradation was reached at the end of this time point. Acetic acid was used as a reference substance in the toxicity control and 88% degradation occurred within 14 days (91% after 28 d). Therefore, the substance is regarded to be readily biodegradable.