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:
14.12.10 – 24.02.11
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: study performed following OECD 301 F and the lab is certified GLP

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2010
Report Date:
2011

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 301 F (Ready Biodegradability: Manometric Respirometry Test)
Deviations:
no
GLP compliance:
yes (incl. certificate)

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
Product name: LCE 10077
Product code: 07/00012; Lot: T01745
Form: solid
Origin: Safety Data Sheet of 01.02.07
purity:100%
substance type: UVCB
Specific details on test material used for the study:
Details on properties of test surrogate or analogue material (migrated information):
PHYSICO-CHEMICAL PROPERTIES
- Melting point:
- Boiling point:
- Vapour pressure:
- Henry's law constant (for volatie substances):
- Water solubility (under test conditions):
- Solubility in organic solvents:
- log Pow:
- Stability of test material at room temperature:stable


OTHER PROPERTIES (if relevant for this endpoint)
- Toxicity to microorganisms:no

PHYSICO-CHEMICAL PROPERTIES
- Vapour pressure:extrapolated at 25 °C is 1.7 x 10-3 Pa.
- Water solubility (under test conditions):The test item is a solid soluble in water and was put directly into the test ves-sels.
- log Pow:Therefore, the log P of LCE10027 is equal to 7.7.


OTHER PROPERTIES (if relevant for this endpoint)
- Adsorption characteristics:adsorption/desorption coefficient on soil and on sewage sludge can be
estimated to be higher then 2.4.
- Toxicity to microorganisms: none
- Other:

Study design

Oxygen conditions:
aerobic
Inoculum or test system:
activated sludge (adaptation not specified)
Details on inoculum:
Activated sludge from the municipal sewage treatment plant Reutlingen-West was washed two times with tap water and filtered (Liquid jet vacuum pump with Filter paper circles, Schleicher & Schuell); 1 g of the wet filtrate corresponded to approximately 60 mg suspended solids. Using a test volume of 250 mL, 100 mg of the wet filtrate were inserted per flask, corresponding to 24 mg sus-pended solids per litre.
Duration of test (contact time):
28 d
Initial test substance concentration
Initial conc.:
100 mg/L
Based on:
act. ingr.
Parameter followed for biodegradation estimation
Parameter followed for biodegradation estimation:
other: biological oxygen demand: BOD
Details on study design:
- Dilution water: Deionised water was aerated for 2 h with a membrane pump and allowed to stand for 0.5 h before usage. This water was used for preparation of the mineral medium for the blanks and as dilution water for the test item and reference item.
- Mineral medium: The following stock solutions were prepared:
solution 1: KH2PO4 8.50 g/L
K2HPO4 21.75 g/L
Na2HPO4 x 2 H2O 33.40 g/L
NH4Cl 0.50 g/L
solution 2: CaCl2 x 2 H2O 27.50 g/L
solution 3: MgSO4 x 7 H2O 22.50 g/L
solution 4: FeCl3 x 6 H2O 0.25 g/L
The stock solutions were diluted in deionised water for preparation of the Min-eral medium for test flasks 1 – 6 directly before the start of the test. 1 L of the Mineral medium included 10 mL of solution 1 and 1 mL of solutions 2 – 4.


- Apparatus: BOD-digi (SELUTEC GmbH), electrolytic oxygen supply with automatic data registration and temperature regulation.
- Incubation: 28 days, stirred culture at 22 ± 2 °C, incubator.
- Test item: The test item is a solid soluble in water and was put directly into the test ves-sels.
- Reference
item: Sodium-Benzoate in Mineral medium.

Flasks: 1: Test item in Mineral medium + inoculum
2: Test item in Mineral medium + inoculum
3: Mineral medium + inoculum (blank)
4: Mineral medium + inoculum (blank)
5: Reference item Sodium-Benzoate in Mineral medium + inoculum
6: Test item in Mineral medium, sterilised with HgCl2/L
(C HgCl2 = 10 g/L; abiotic control)
Reference substance
Reference substance:
benzoic acid, sodium salt

Results and discussion

% Degradationopen allclose all
Parameter:
other: ThOD
Value:
ca. 49.4
Sampling time:
14 d
Parameter:
other: ThOD
Value:
ca. 41.2
Sampling time:
10 d
Parameter:
other: ThOD
Value:
ca. 84
Sampling time:
28 d
Details on results:
The validity criteria of OECD-Guideline 301 F are accomplished:
- Maximum BOD-difference in flasks 1 + 2 at the end of the test: 0.7 % (nominal value: < 20 %)
- Mean value of inoculum blank: 23.6 mg O2/L (nominal value:  60 mg O2/L)
- Biodegradation of reference item after 14 d: 89.7 % (nominal value: > 60 %)

BOD5 / COD results

BOD5 / COD
Parameter:
BOD5
Value:
ca. 2.29 g O2/g test mat.
Results with reference substance:
Reference item:
- Test concentration: 100.4 mg/L
- ThOD of the reference item: 1.67 mg O2/mg reference item
- ThOD in flask 5: 167.7 mg O2/L
- BOD in flask 5 after 28 days: 184.3 mg O2/L (including blank)
- BODreference item - BODinoculum blank: 160.7 mg O2/L
or: 1.60 mg O2/mg reference item
- Biodegradation after 14 days: 89.7 %
- Biodegradation after 28 days: 95.8 %
- 10 days window: 87.3 %
The pH in flask 5 originally was 7.7 and was corrected to 7.5 by addition of 1 N HCl at the beginning of the test. At the end of the test the pH in flask 5 was 7.8.

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Interpretation of results:
readily biodegradable, but failing 10-day window
Conclusions:
The test item LCE 10077 achieved 84.0 % biodegradation in 28 days (10 days window: 41.2 %) in a Manometric Respirometry Test conducted according to OECD-Guideline 301 F.
The test item LCE 10077 is readily biodegradable not meeting the 10 days window.
Executive summary:

The test item LCE 10077 achieved 84.0 % biodegradation in 28 days (10 days window: 41.2 %) in a Manometric Respirometry Test conducted according to OECD-Guideline 301 F. The test item LCE 10077 is readily biodegradable not meeting the 10 days window.