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, Guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1999
Report Date:
1999

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 301 D (Ready Biodegradability: Closed Bottle Test)
GLP compliance:
yes (incl. certificate)

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
Batch No GST7-18099

Study design

Oxygen conditions:
aerobic
Inoculum or test system:
activated sludge, adapted
Details on inoculum:
Effluent from a strongly aerated laboratory activated sludge plant (RBM plant). The effluent wa kept under aerobic conditions in the period between sampling and application. To prepare the inoculum the sample was filtered through a coarse filter, the first 200 ml being dicarded. The rest of the filtrate was kept aerobic until use. The inoculum was used on the day of collection.
Duration of test (contact time):
28 d
Initial test substance concentration
Initial conc.:
2 mg/L
Based on:
test mat.
Parameter followed for biodegradation estimation
Parameter followed for biodegradation estimation:
O2 consumption
Reference substance
Reference substance:
acetic acid, sodium salt

Results and discussion

Preliminary study:
The COD of Pyrazole DHE was 0.666 mg O2 /mg
The ThOD (NH4) is 0.533 mg O2 / mg
The Biodegradability percentages obtained on day 7,14,21 and 28 were 18.9, 26.5, 27.3 and 33.3 of the experimental COD of the test article and 23.5, 32.8, 33.8 and 41.3 of its ThOD NH4.
% Degradation
Parameter:
% degradation (O2 consumption)
Value:
33.3
Sampling time:
28 d

BOD5 / COD results

BOD5 / COD
Parameter:
COD
Value:
0.66 mg O2/g test mat.

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Interpretation of results:
inherently biodegradable
Conclusions:
Pyrazole DHE (batch GSF 7 -18099) can be considered neither as readily biogdegradable, nor inhibitory on the bacteria inoculum at the concentration (2mg/l) used.
Executive summary:

The study was perfomed according OECD Guideline 301 to evaluate the biogradability of Pyrazole DHE:

Results:

The Biodegradability percentages obtained on day 7,14,21 and 28 were 18.9, 26.5, 27.3 and 33.3 of the experimental COD of the test article and 23.5, 32.8, 33.8 and 41.3 of its ThOD NH4.

Therefore untder the conditions adopted in this study the test substance Pyrazole DHE (batch GSF 7 -18099) can be considered neither as readily biogdegradable, nor inhibitory on the bacteria inoculum at the concentration (2mg/l) used.