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:
study report
Title:
Unnamed
Year:
2019
Report Date:
2019

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

Study design

Oxygen conditions:
aerobic
Inoculum or test system:
activated sludge (adaptation not specified)
Details on inoculum:
- Storage conditions: The test item was stored in the test facility in a tightly closed vessel at room temperature (20 ± 5 °C).
Duration of test (contact time):
ca. 28 d

Results and discussion

% Degradationopen allclose all
Key result
Parameter:
% degradation (DOC removal)
Value:
ca. 45.6
Sampling time:
28 d
Key result
Parameter:
% degradation (DOC removal)
Value:
ca. 49.4
Sampling time:
28 d

BOD5 / COD results

BOD5 / COD
Key result
Parameter:
BOD5
Value:
ca. 100.25 other: mgO2/L
Results with reference substance:
The degree of biodegradation reached 48 % after 28 days.
The 10-day-window began on day 10 (this is stated as lag phase), at its end (day 20),
38.8 % were reached, staying below the pass level of 60 % given in the OECD guideline.
The degradation phase is defined as interval between the end of the lag phase and the reaching of 90 %. This was reached on day 23.
The degradation phase was from day 10 – day 23 (42.75 %).

Therefore, when applying the 10-day-window, the test item Naphtha/Light Oil is not readi-ly biodegradable following OECD 301F/EU C.4-D.
Because the test item is a mixture the 10-day-window does not have to be taken into ac-count. As degradation missed 60% in the course of the test, Naphtha/Light Oil is consid-ered as not readily biodegradable within 28 days, as well.

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Interpretation of results:
not readily biodegradable
Conclusions:
As degradation missed 60% in the course of the test, Naphtha/Light Oil is considered as not readily biodegradable within 28 days, as well.