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)
Rationale for reliability incl. deficiencies:
other: GLP- and Guideline Study with no deviations.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2015

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

Constituent 1
Chemical structure
Reference substance name:
ethyl {[4-(5-oxo-4,5-dihydro-1,2,4-oxadiazol-3-yl)phenyl]amino}acetate
EC Number:
927-587-4
Cas Number:
872728-83-1
Molecular formula:
C12 H13 N3 O4
IUPAC Name:
ethyl {[4-(5-oxo-4,5-dihydro-1,2,4-oxadiazol-3-yl)phenyl]amino}acetate
Test material form:
solid

Study design

Oxygen conditions:
aerobic
Inoculum or test system:
activated sludge, domestic, adapted
Details on inoculum:
Activated sludge from the municipal wastewater treatment plant Breisgauer Bucht was used as inoculum with a concentration corresponding to 30 mg dry solids per litre. The treatment plant clarifies predominantly domestic wastewater of the region of Freiburg and has a capacity of 600.000 inhabitant equivalents. Sampling date of activated sludge was June 23rd, 2015. Dry solid of the activated sludge was determined as 4.5 g/L by weight measurements after 2.0 h drying at 105°C (mean of triplicate measurements). The activated sludge was washed twice with tap water by settling the sludge,
decanting the supernatant and resuspending the sludge.
Duration of test (contact time):
28 d
Initial test substance concentration
Initial conc.:
100 mg/L
Based on:
ThOD/L
Details on study design:
The stock solution of the test item, sodium acetate and the toxicity control (test item + sodium acetate) was added into the vessels.
After tempering the vessels to the incubation temperature for 1 hours 15 minutes, 1.09 ml of the inoculum were added into each vessel,
one sodium hydroxide pellet was added to each rubber quiver inserted in the vessels and the vessels were sealed tightly with the measuring
heads and the test was started. After 28 days the data were read out and the pH in the flasks was measured.
Reference substance
Reference substance:
acetic acid, sodium salt

Results and discussion

% Degradation
Parameter:
% degradation (TOC removal)
Value:
<= 20
Sampling time:
28 d

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Interpretation of results:
other: not readily biodegradable
Conclusions:
The biodegradation of the test item was 16.0% within 28 days (mean value of three replicates, see table 2). Therefore the criterion for ready
biodegradability was not met (60% ThOD and 10-day window).