Registration Dossier

Environmental fate & pathways

Biodegradation in water: screening tests

Currently viewing:

Administrative data

Endpoint:
biodegradation in water: ready biodegradability
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: see 'Remark'
Remarks:
The authors tested the biodegradability of benzotrichloride according to the OECD guideline 301E. GLP standards are not specified and no data are available for validity criteria fulfillment. However, the study is sufficiently described. Thus the study should be considered a Klimisch 2c study as it is comparable to a guideline study with acceptable restrictions.

Data source

Reference
Reference Type:
publication
Title:
Versuche zur biologischen Abbaubarkeit chlororganischer Verbindungen
Author:
Steinhäuser K.G., Amann W. and Polenz A.
Year:
1986
Bibliographic source:
Vom Wasser, 67, 147-154.

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 301 E (Ready biodegradability: Modified OECD Screening Test)
Deviations:
yes
Remarks:
one replicate only
GLP compliance:
not specified

Test material

Reference
Name:
Unnamed
Type:
Constituent
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): Benzotrichloride
No more data available

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): predominantly domestic sewage
No more data available
Duration of test (contact time):
28 d
Initial test substance concentrationopen allclose all
Initial conc.:
5.4 mg/L
Based on:
test mat.
Initial conc.:
22 mg/L
Based on:
test mat.
Parameter followed for biodegradation estimation
Parameter followed for biodegradation estimation:
DOC removal
Details on study design:
TEST SYSTEM
- Number of culture flasks/concentration: 2 concentrations; 5.4 and 22 mg/L
No more data available


SAMPLING
- Sampling frequency: Weekly with an extra time point after 3 days
No more data available


CONTROL AND BLANK SYSTEM
- Toxicity control: yes
No more data available


STATISTICAL METHODS:
No data available
Reference substance
Reference substance:
benzoic acid, sodium salt

Results and discussion

Preliminary study:
No data available
Test performance:
No data available
% Degradationopen allclose all
Parameter:
% degradation (DOC removal)
Value:
95
Sampling time:
3 d
Remarks on result:
other: Test substance concentration 5.4 mg/L
Parameter:
% degradation (DOC removal)
Value:
96
Sampling time:
7 d
Remarks on result:
other: Test substance concentration 5.4 mg/L
Parameter:
% degradation (DOC removal)
Value:
95
Sampling time:
3 d
Remarks on result:
other: Test substance concentration 22 mg/L
Parameter:
% degradation (DOC removal)
Value:
97
Sampling time:
7 d
Remarks on result:
other: Test substance concentration 22 mg/L

BOD5 / COD results

Results with reference substance:
No data

Any other information on results incl. tables

- Chloride formation by degradation of the test substance was also measured (see table below)

- A control for abiotic degradation (precipitation, adsorption and volatilisation) of the test substance was performed (test substance without inoculum) (see table below)

Table:

Initial concentration testsubstance (mg/L) DOC removal in % (days) Chloride formation by degradation in % (days)
3 7 14 21 28 0 3 7 14 21 28
5.4 95 96 105 111 108
22 95 97 103 100 112
Control for abiotic degradation 5.5 1 11 102 110 107

Applicant's summary and conclusion

Validity criteria fulfilled:
not specified
Interpretation of results:
readily biodegradable
Conclusions:
In the test conditions, benzotrichloride was assessed to be readily biodegradable in an OECD guideline 301E test after 7 days of incubation.
Executive summary:

The authors tested the biodegradability of the benzotrichloride (CAS n° 98 -07 -7) according to the OECD guideline 301E. They also monitored the formation of the main degradation product, inorganic chloride. For a concentration of 5.4 and 22 mg/L, 96% and 97% of the DOC respectively was removed after 7 days. They confirmed abiotic degradation did not occur by testing a control without innoculum. Thus, at this level of information, benzal chloride should be considered as readily biodegradable according to the EC regulation n° 1272/2008 and the former 67/548/EC regulation.

No data was available on the GLP status of the study. None of the validity criteria was sufficiently documented to check their fulfillment. However, the authors followed the OECD guideline 301E and documented sufficiently their study to consider this study as reliable with restrictions and comparable to a guideline study with acceptable restrictions.