bis(trifluoromethylsulfonyl)azanide;1-ethyl-3-methylimidazol-3-ium

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:

Study Plan dated: 10.Jan 2018 Experimental Starting Date: 31.Jan. 2018 Experimental Completion Date: 01.Mar. 2018

Reliability:

1 (reliable without restriction)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Report date:

2018

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 310 (Ready Biodegradability - CO2 in Sealed Vessels (Headspace Test)

Version / remarks:

23. Mar. 2006, corrected 26. Sep. 2014

Deviations:

yes

Remarks:

• Temperature range was 19.8 – 21.8 °C instead of 20.0 ± 1.0 °C. As degradation of the positive control was in the normal range this is considered as uncritical concerning the outcome of the study.

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method C.29 (Ready Biodegradability - CO2 in Sealed Vessels (Headspace Test))

Version / remarks:

24. Jan. 2014

Deviations:

yes

Remarks:

• Temperature range was 19.8 – 21.8 °C instead of 20.0 ± 1.0 °C. As degradation of the positive control was in the normal range this is considered as uncritical concerning the outcome of the study.

Test guideline 3

Qualifier:

according to guideline

Guideline:

ISO 14593:1999 (Water quality - Evaluation of ultimate aerobic biodegradability of organic compounds in aqueous medium - Method by analysis of inorganic carbon in sealed vessels (CO2 headspace test))

Version / remarks:

2005

Deviations:

yes

Remarks:

• Temperature range was 19.8 – 21.8 °C instead of 20.0 ± 1.0 °C. As degradation of the positive control was in the normal range this is considered as uncritical concerning the outcome of the study

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

1-ethyl-3-methyl-1H-imidazol-3-ium; trifluoro[(trifluoromethanesulfonylazanidyl)sulfonyl]methane

EC Number:

700-235-5

Cas Number:

174899-82-2

Molecular formula:

C8H11F6N3O4S2

IUPAC Name:

1-ethyl-3-methyl-1H-imidazol-3-ium; trifluoro[(trifluoromethanesulfonylazanidyl)sulfonyl]methane

Test material form:

liquid

Details on test material:

clear liquid, colorless

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: proionic GmbH; 25PI208_12
- Expiration date of the lot/batch: May 2019
- Purity test date: 99.84 wt% (HPLC); 99.95 wt% (IC)


STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: room temperature

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic (adaptation not specified)

Details on inoculum:

The sludge was taken from the activation basin of the ESN (Stadtentsorgung Neustadt) sewage treatment plant, Im Altenschemel, NW-Lachen-Speyerdorf.
Date of collection: 01. Feb. 2018

Duration of test (contact time):

28 d

Details on study design:

This study was performed in order to evaluate the aerobe degradation potential of 1-Ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide by aerobe micro-organisms at a given concentration.
The test item as the sole source of carbon and energy, was incubated in a buffer-mineral salts medium which was inoculated with a mixed population of micro-organisms. The test was performed in sealed bottles with a headspace of air, which provides a reservoir of oxygen for aerobic biodegradation. The CO2 evolution resulting from the ultimate aerobic biodegradation of the test item was determined by measuring the IC produced in the test bottles in excess of that produced in blank control vessels containing inoculated medium only. The extent of biodegradation was expressed as a percentage of the theoretical max-imum IC production (ThIC), based on the quantity of test item (as organic carbon) added initially.

Reference substance

Reference substance:

aniline

Results and discussion

Test performance:

The test was performed at room temperature (19.8 - 21.8 C) without direct lighting.
Duration of the test was 28 days. During this time, the created CO2 in the vessels was de-termined on days 0, 4, 7, 11, 14, 19, 22, 28.

% Degradation

Key result

Parameter:

% degradation (inorg. C analysis)

Value:

0.72

Sampling time:

28 d

BOD5 / COD results

Results with reference substance:

%degradation (inorg. C analysis): 87.14

Any other information on results incl. tables

Parameter	Value
10-day-window	not detectable
Degradation at the end of 10-day-window	none
Degradation at the end of the test	1%

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

not readily biodegradable

Conclusions:

The validity criteria were met.
If degradation in the toxicity flask is below 25% at the end of the test, the test item can be considered as toxic towards the inoculum. As degradation in the toxicity flask was 41 % at the end of the test, the test item can be stated as “not toxic towards the inoculum in a con-centration of 86.7 mg/l”.
In the OECD guideline ready degradability is defined as degradation surpassing 60% within 10 days after reaching a level of 10 %. Therefore, the test item can be considered as “not readily biodegradable”. As degradation missed 60 % within 28 days, the test item is considered as “not ultimately biodegradable within 28 days”, either.
Because the test item is not readily biodegradable, in 1 test flask without addition of NaOH the pH was measured. If the pH is below 6.5 nitrification is possible. The measured pH was 7.4. Therefore, no nitrification has occurred.

The result of the test can be considered valid.

Executive summary:

The test item was tested using a concentration of 86.7 mg1-Ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide/L in test medium.

Aniline was chosen as positive control.

Activated sludge from a sewage treating plant was used as inoculum (concentration 4.0 mg suspended solids/L). The test was left running for 28 days.

All validity criteria were met. Degradation of the positive control was 72 % after 7 days.

 

The following data were determined for the test item1-Ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide:

10-day-window:                                                                                                          not detectable

degradation at the end of 10-day-window                                                                             none

degradation at the end of the test                                                                                              1 %

Therefore,1-Ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imideisnot readily biodegradablefollowing OECD 310.As degradation missed 60 % within 28 days, the test item is considered as “not ultimately biodegradable within 28 days”, either.