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:
supporting study
Study period:
1996-05-14 to 1996-08-30
Reliability:
3 (not reliable)
Rationale for reliability incl. deficiencies:
other: Calculation of the degradation rate is done with values in the wrong units. This leads to completely wrong degradation rates.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1996
Report Date:
1996

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:
- Name of test material (as cited in study report): Monochloracetone
- Physical state: liquid
- Analytical purity: 96.18 %
- Impurities (identity and concentrations): 1,3-Dichloracetone (0.5%); 4-Methylpent-3-en-2-on (1%); 1,1-Dichloracetone (3%)
- Lot/batch No.: 603015
- Expiration date of the lot/batch: March 12, 1997
- Stability under test conditions: room temperature, dark
- Storage condition of test material: moderat stable

Study design

Oxygen conditions:
aerobic
Inoculum or test system:
sewage, predominantly domestic (adaptation not specified)
Details on inoculum:
- Source of inoculum/activated sludge (e.g. location, sampling depth, contamination history, procedure): municipal waste water treatment plant Bitterfeld-Wolfen
Duration of test (contact time):
28 d
Initial test substance concentration
Initial conc.:
2 mg/L
Based on:
formulation
Parameter followed for biodegradation estimation
Parameter followed for biodegradation estimation:
O2 consumption
Reference substance
Reference substance:
acetic acid, sodium salt

Results and discussion

% Degradationopen allclose all
Parameter:
% degradation (O2 consumption)
Value:
59.9
Sampling time:
28 d
Remarks on result:
other: re-evaluated by the applicant
Parameter:
% degradation (O2 consumption)
Value:
0
Sampling time:
28 d
Remarks on result:
other: degradation not correctly calculated

Applicant's summary and conclusion

Validity criteria fulfilled:
not applicable
Interpretation of results:
other: not readily biodegradable
Conclusions:
Monochloroaceton was not readily biodegradable under the conditions of the test. The biodegradation rate was 59.9 %
Executive summary:

Monochloroacetone was examined for ready biodegradability according OECD Guideline 301D. The Theoretical oxygen demand (ThOD) was not correctly calculated in the original report and expressed in units that led to a completely wrong value for the degradation rate of the test substance. The ThOD must have been 1.21 mg/mg as recalculated with the formula given in the OECD Guidelines. The degradation rates in Table 3 of the test report were therefore recalculated with the correct ThOD. Monochloroaceton was not readily biodegradable under the conditions of the test. The biodegradation rate was 59.9 %. The procedure control worked as expected and the toxicity control did not indicate toxicity to suldge.