Ruscus aculeatus, ext.

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:

2013

Reliability:

1 (reliable without restriction)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2013

Report date:

2013

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 D (Ready Biodegradability: Closed Bottle Test)

Deviations:

no

Test guideline 2

Guideline:

EPA OPPTS 835.3110 (Ready Biodegradability)

Deviations:

no

Principles of method if other than guideline:

Preparation of Activated sludge inoculum: The activated sludge used for this study was washed by centrifugation and the supernatant liquid phase was decanted. The solid material was re-suspended in isotonic saline solution with shaking and again centrifuged. This procedure was repeated twice. An aliquot of the final sludge suspension was weighed, dried and the ratio of wet sludge to dry weight determined. Based on this ratio, calculated aliquots of washed sludge suspension, corresponding to 5g dry material per litre was mixed with reconstituted water and then aerated until use (in this study 200 mL inoculum was prepared). After preparation the sludge was filtered through cotton wool. The pH of the activated sludge inoculum after preparation was: 6.71. A pH adjustment before use was not performed. The microbial inoculum was prepared on the day of the test and was not pre-adapted to the test chemical. The microbial inoculum was continuously aerated (2 L/min) at the test temperature of until use

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Ruscus aculeatus, ext.

EC Number:

281-682-9

EC Name:

Ruscus aculeatus, ext.

Cas Number:

84012-38-4

Molecular formula:

not applicable

IUPAC Name:

Ruscus aculeatus, ext.

Test material form:

solid

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic (adaptation not specified)

Duration of test (contact time):

28 d

Initial test substance concentration

Initial conc.:

4 mg/L

Based on:

COD

Results and discussion

Preliminary study:

In the preliminary experiment the test item concentration of 3 mg/L was investigated for 14 days. The test design was the same as described at the main experiment. No toxic effect of the test item was found at the investigated concentration. (In the tocicity control containing both, the test item and reference item, a mean of 45.3% biodegradation was noted within 14 days, thus, the test item was assumed not to inhibit the activated sludge microorganisms (higher than 25% degradation occured within 14 days).

% Degradation

Key result

Parameter:

% degradation (test mat. analysis)

Value:

>= 42 - <= 44.2

Sampling time:

28 d

BOD5 / COD results

BOD5 / COD

Key result

Parameter:

COD

Value:

60 mg O2/g test mat.

Remarks on result:

other: the test item is consideredto be not ready biodegradable

Results with reference substance:

Reference attachment

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

not readily biodegradable

Conclusions:

Reference attachment