Rhatany, Krameria triandra, 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:

13.07.2018 - 30.10.2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

The study was performed in compliance with the Principle of Good Laboratory Practice, confirmed by Statement of GLP Compliance.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 B (Ready Biodegradability: CO2 Evolution Test)

Principles of method if other than guideline:

None known.

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

1

Reference substance name:

Rhatany, Krameria triandra, ext.

EC Number:

283-919-1

EC Name:

Rhatany, Krameria triandra, ext.

Cas Number:

84775-95-1

Molecular formula:

not available

IUPAC Name:

Extractives and their physically modified derivatives such as tinctures, concretes, absolutes, essential oils, oleoresins, terpenes, terpene-free fractions, distillates, residues, etc., obtained from Krameria triandra, Krameriaceae.

Test material form:

liquid: viscous

Specific details on test material used for the study:

Name Krameria triandra extract obtained from Rhatany root by hydroalcoholic extraction
Batch no. PES180014
Appearance reddish brown viscous substance
Composition Krameria triandra extract obtained from Rhatany root by hydroalcoholic extraction
CAS No. 84775-95-1
EINECS-No. 283-919-1
Molecular formula not stated
Molecular weight not applicable, UVCB
Purity not applicable, UVCB
Homogeneity unhomogeneous, warm up about 60 °C and stir
Vapour pressure unknown
Stability in solvents H2O: 96h; EtOH: 96h; acetone: 96h; CH3CN: 96h; DMSO: 96h
Solubility in solvents H2O: unknown; EtOH: >1 g/L; acetone: >1 g/L; CH3CN: >1 g/L; DMSO: >1 g/L
Production date Jan. 2018
Expiry date Jan. 2019
Storage Fridge (2 - 8 °C)

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic (adaptation not specified)

Details on inoculum:

Preparations:
The medium was prepared from the stock solutions. The stock solution of the positive control was prepared and its DOC was measured. The inoculum was taken from its source, washed, aerated and the dry matter was determined.
The test vessels were filled with medium and inoculum. Then, all flasks were aerated for 72 hours with purified, CO2-free, moistened air to purge the system of CO2.

Experimental Parameters:
Flask volume 1500 mL
Apparatus blanks 2, containing mineral medium only
Blank Controls 2, containing mineral medium and inoculum
Positive control flasks 2, containing positive control, mineral medium and inoculum
Test flasks 2, containing test item, mineral medium and inoculum
Abiotic control 1, containing test item, mineral medium and HgCl2
Toxicity control 1, containing test item, positive control, mineral medium and inoculum
Inoculum concentration: 25.0 mg/L
Temperature 20.1 – 22.8 °C without direct lighting
Duration 28 days
The test was performed with a nominal start concentration of 20 mg organic carbon/L of the test item.

Duration of test (contact time):

< 28 d

Details on study design:

Pre-Treatment:
The carbon content of 33.40 % was determined by elemental analysis under non-GLP conditions, performed at the laboratory Mikroanalytisches Labor Pascher, An der Pulvermühle 1, 53424 Remagen, Germany. The test item was warmed up to 60 °C and stirred, and then it was added to the flasks directly, according to the nominal amount of organic carbon calculated from elemental analysis.

Test System:

Specification:
Activated sludge from a biologic sewage treatment plant was used as inoculum. The chosen plant treats mostly domestic sewage.

Source and Pre-Treatment of inoculum:
Source
The sludge was taken from the activation basin of the ESN (Stadtentsorgung Neustadt) sewage treatment plant, Im Altenschemel, 67435 NW-Lachen-Speyerdorf.
Date of collection: 28. Sep. 2018, batch no: 20180928.
Pre-Treatment
The sludge was filtrated, washed with test medium (2x) and re-suspended in test medium. It was then aerated until use. The dry matter was determined to contain 4940 mg of suspended solids/L.

Reference substance

Reference substance:

aniline

Remarks:

(Phenylamine, C6H5NH2, CAS-No. 62-53-3) was used as readily biodegradable positive control. A stock solution containing 2099.8 mg/L in deionised water was prepared and its organic carbon content was measured with 1731.5 mg/L.

Results and discussion

% Degradation

% Degradation 1

Parameter:

% degradation (CO2 evolution)

Value:

> 2.1 - < 5.1

Sampling time:

3 d

% Degradation 2

Parameter:

% degradation (CO2 evolution)

Value:

> 2.6 - < 12

Sampling time:

7 d

% Degradation 3

Parameter:

% degradation (CO2 evolution)

Value:

> 5.1 - < 14.7

Sampling time:

9 d

% Degradation 4

Parameter:

% degradation (CO2 evolution)

Value:

> 6.8 - < 16.4

Sampling time:

11 d

% Degradation 5

Parameter:

% degradation (CO2 evolution)

Value:

> 15.3 - < 20

Sampling time:

14 d

% Degradation 6

Parameter:

% degradation (CO2 evolution)

Value:

> 19.9 - < 23.5

Sampling time:

17 d

% Degradation 7

Parameter:

% degradation (CO2 evolution)

Value:

> 23.7 - < 27.2

Sampling time:

23 d

% Degradation 8

Key result

Parameter:

% degradation (CO2 evolution)

Value:

> 23.5 - < 32

Sampling time:

29 d

Details on results:

The test item Krameria triandra extract obtained from Rhatany root by hydroalcoholic extraction was tested using a concentration of nominally 20 mg organic carbon/L Krameria triandra extract obtained from Rhatany root by hydroalcoholic extraction in test medium following OECD 301B and EU-Method C.4-C.

Aniline was chosen as positive control.
Activated sludge was used as inoculum (concentration in the test 25.0 mg dry matter/L). The test was left running for 28 days.
All validity criteria were met. Degradation of the positive control surpassed the pass level of 60 % after 10 days.

The following data were determined for the test item Krameria triandra extract obtained from Rhatany root by hydroalcoholic extraction:
10-day-window: day 9 – 19
degradation at the end of 10-day-window 23 %
degradation at the end of the test 28 %
pass level following guideline: 60 % at the end of 10-day-window for pure substances
respective 60 % at the end of the test for mixtures

Therefore, when applying the 10-day-window, Krameria triandra extract obtained from Rhatany root by hydroalcoholic extraction is not readily biodegradable following OECD 301B and EU C.4-C respectively.
Because the test item is a mixture the 10-day-window does not have to be taken into account. As degradation missed 60% in the course of the test, Krameria triandra extract obtained from Rhatany root by hydroalcoholic extraction is considered as not readily biodegradable.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Remarks:

All validity criteria were met. Degradation of the positive control surpassed the pass level of 60 % after 10 days.

Interpretation of results:

not readily biodegradable

Conclusions:

All validity criteria were met.
Degradation behaviour of positive control and toxicity control was normal. Abiotic degradation reached 0.3 %. Both replicates of the test item showed good correspondence.
If degradation in the toxicity flask is below 25 % after 14 days, the test item can be con-sidered as toxic towards the inoculum. As degradation in the toxicity flask was 48.7 % after 14 days, the test item can be stated as “not toxic towards the inoculum in a concentration of 60.5 mg/L”.
For pure substances ready biodegradability is defined in the guidelines as degradation surpassing 60 % within 10 days after reaching a level of 10 %.
Because the test item is a mixture, the 10-day window has not to be taken into account. As degradation missed 60% in the course of the test, Krameria triandra extract obtained from Rhatany root by hydroalcoholic extraction is considered as not readily biodegradable, within 28 days.
No observations were made which might cause doubts concerning the validity of the study outcome.
The result of the test can be considered valid.

Executive summary:

This study was performed in order to evaluate aerobic elimination and degradation potential of Krameria triandra extract obtained from Rhatany root by hydroalcoholic extractionin a test for ready biodegradability, using a test item concentration of nominally 20 mg organic carbon/L Krameria triandra extract obtained from Rhatany root by hydroalcoholic extraction.

The test item in a mineral medium was inoculated and incubated under aerobic conditions in the dark. The amount of DOC in the test solution due to the inoculum was kept as low as possible compared with the amount of organic carbon due to the test item. Allowance was made for the endogenous activity of the inoculum by running parallel blanks with inoculum but without test item. A positive control was run in parallel to check the operation of the procedures. Degradation was followed by determining the carbon dioxide produced. Measurements were taken at sufficiently frequent intervals to allow the identification of the beginning and end of biodegradation.

The test lasted for 28 days.

 Results for the Test Item

The test item Krameria triandra extract obtained from Rhatany root by hydroalcoholic extractionis considered as “not readily biodegradable“.

The degree of biodegradation reached 28 % after 28 days.

The 10-day-window began on day 9, at its end, 23 % degradation were reached, missing the pass level of 60 % given in the OECD guideline.

Because the test item is a mixture, the 10-day window has not to be taken into account. As degradation missed 60% in the course of the test, Krameria triandra extract obtained from Rhatany root by hydroalcoholic extractionis considered as not readily biodegradable, within 28 days.

The abiotic degradation reached 0.3 %.