Extract from the seeds of Trigonella foenum-graecum (Fabaceae) obtained by extraction with polar solvents

Biodegradation in water: screening tests

Link to relevant study record(s)

Reference

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

9 December 2019 - 7 January 2020

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.4-E (Determination of the "Ready" Biodegradability - Closed Bottle Test)

Deviations:

no

Qualifier:

according to guideline

Guideline:

ISO 10707 Water quality - Evaluation in an aqueous medium of the "ultimate" aerobic biodegradability of organic compounds - Method by analysis of biochemical oxygen demand (closed bottle test)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

Test item name :Extract from the seeds of Trigonella foenum-graecum (Fabaceae) obtained by extraction with polar solvents
Identification/Synonym: FENUGREEK EXTRACT
Substance type: UVCB substance
EC No.: 950-727-0
Appearance: liquid, viscous, clear, dark brown

Oxygen conditions:

aerobic

Inoculum or test system:

natural water: freshwater

Details on inoculum:

Origin: River water was sampled from “La Mourachonne”, situated downstream of a plant treating domestic wastewater (Pegomas, France).
Pre-conditioning: The river water was aerated for about 6 days before use as inoculum at the test temperature to reduce endogenous respiration.
A concentration of inoculum of approx. 2.5x1^05 cells.L-1 was used.

Duration of test (contact time):

28 d

Initial conc.:

2 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

Water Accommodated Fractions (WAFs) were prepared under closed conditions and by slow-stirring. Then the WAFs were slightly diluted with a fixed amount of inoculum as necessary into 5-L volumetric flasks to obtain the required test concentration (2 mg.L-1, nominal) and filled into test vessels. No small bubble was observed in the test vessels. The test was carried out without adjustment of the pH.
- 10 bottles containing inoculum and mineral medium (inoculum blank)
- 10 bottles containing test item, inoculum and mineral (test suspension)
- 6 bottles containing reference substance, inoculum and mineral medium (procedure control)
- 6 bottles containing test item, reference substance, inoculum and mineral medium (toxicity control)

Reference substance:

benzoic acid, sodium salt

Test performance:

Oxygen depletion in the inoculum blank did not exceed 1.5 mg dissolved oxygen.L-1 after 28 days.
Oxygen concentrations were > 0.5 mg.L-1 in all bottles during the test period.
The differences of the replicate (test suspension) values at day 28 were less than 20%.
The biodegradation percentage of the reference substance, sodium benzoate, was 80% at day 14.

Key result

Parameter:

% degradation (O2 consumption)

Value:

84

Sampling time:

28 d

Key result

Parameter:

COD

Value:

0.814 mg O2/g test mat.

Results with reference substance:

In the toxicity control containing both the test item and reference item sodium benzoate, 79% of biodegradation was noted at day 7 and 81% of biodegradation at day 14 of the test.

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable

Conclusions:

In this study, test item was biodegraded by 84% (mean) at day 28. Therefore, under the test conditions and according to the requirements of the test guideline, the test substance can be considered as readily biodegradable.

Description of key information

The substance can be considered readily biodegradable (84%) according to the test guideline OECD 301D.

Key value for chemical safety assessment

Biodegradation in water:

readily biodegradable

Type of water:

freshwater