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
Study period:
december 2017 to january 2018
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2018
Report Date:
2018

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 301 F (Ready Biodegradability: Manometric Respirometry Test)
GLP compliance:
yes

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
liquid
Specific details on test material used for the study:
batch number 4802

Study design

Oxygen conditions:
aerobic
Inoculum or test system:
activated sludge, domestic, non-adapted
Details on inoculum:
water treatment plant "STEP de Lille" 33290 Blanquefort (France) - The inoculum was a fresh sample of activated sludge and was collected from the aeration tank of a sewage treatment plant receiving predominantly domestic sewage.
Duration of test (contact time):
28 d
Details on study design:
The medium was prepared from concentrated stock solutions in ultrapure water as decribed in the guideline.
Reference substance
Reference substance:
other: sodium benzoate

Results and discussion

% Degradation
Key result
Parameter:
% degradation (O2 consumption)
Remarks:
average
Value:
58.44
Sampling time:
28 d
Details on results:
The test item “HUILE ESSENTIELLE DE THUYA OCCIDENTALIS / THUYA OCCIDENTALIS OIL” contains no nitrogen according to the elementary analysis (see Appendix 6: Study plan, Annex 1-2), the evaluation of biodegradation has to be based in the following expressed as ThODNH4.
The degradation for the 10-day window beginning was reached on Day 5, at the end of the 10-day window on Day 15 the mean degradation was 45.87%, therefore the D-day window failed.
The degradation rate of the test item “HUILE ESSENTIELLE DE THUYA OCCIDENTALIS /THUYA OCCIDENTALIS OIL” reached 58.44% (54.40 to 63.05), following the ThODNH4, after 28 days of incubation.

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Interpretation of results:
not readily biodegradable
Conclusions:
The degradation rate of the test item “HUILE ESSENTIELLE DE THUYA OCCIDENTALIS /THUYA OCCIDENTALIS OIL” reached 58.44% (54.40 to 63.05), following the ThODNH4, after 28 days of incubation.
According to the OECD guideline 301F, the test item is not considered to be readily biodegradable.