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)

Data source

Reference
Reference Type:
other: Body responsible for the test
Title:
Unnamed
Year:
1993
Report Date:
1993

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 301 C (Ready Biodegradability: Modified MITI Test (I))
GLP compliance:
yes

Test material

Reference
Name:
Unnamed
Type:
Constituent

Study design

Oxygen conditions:
aerobic
Initial test substance concentration
Initial conc.:
100 mg/L
Parameter followed for biodegradation estimation
Parameter followed for biodegradation estimation:
O2 consumption
Reference substance
Reference substance:
aniline

Results and discussion

% Degradation
Parameter:
% degradation (O2 consumption)
Value:
0
Sampling time:
28 d
Details on results:
Degredation of Aniline exceeds 40% after 7 days and 65% after 14 days: the activity of the inoculum is thus verified and the test is considered as valid.
Degredation of Florhydral is negative: this means that the basal respiration of the slude is slightly reduced in presence of Florhydral, suggesting a slight toxic effect. This is also true for the degredation of Aniline in presence of Florhydral for the first 24 days.

BOD5 / COD results

Results with reference substance:
Degredation of Florhydral is negative: this means that the basal respiration of the slude is slightly reduced in presence of Florhydral, suggesting a slight toxic effect.

Applicant's summary and conclusion

Conclusions:
The biodegradation of Florhydral after 28 days in the test condition is 0%.
This means that Florhydral is not readlily biodegradable.
The curves obtained with Florhydral alone and with Florhydral on the micro-organims. In the latter case, this effect disappers after 24 days and degredation starts: this suggests that Florhydral may be degraded after an acclimatization period in some circumstances.
Executive summary:

The Ready Biodegradability of Florhydral has been determined by the Respirometic Method (modified MITI Test 1) according to the OECD Guidelines for Testing of Chemicals, Method No. 301C. Florhydral is not readily biodegradable in the conditions of the test. At the concentration used in the test (100mg/l), it is slightly inhibitory to the micro-organisms, at least during the first 24 days.