1,2-dimethyl-3-propyl imidazolium bis((trifluoromethyl)sulfonyl)amide

Short-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

14 JUN 2016 to 16 JUN 2016

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2016

Report date:

2018

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Version / remarks:

adopted 13 Apr. 2008

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Version / remarks:

adopted 30. May 2008

Test guideline 3

Qualifier:

according to guideline

Guideline:

other: OECD guidance document no. 23, Guidance Document on Aquatic Toxicity Testing of Difficult Substances and Mixtures

Version / remarks:

adopted 14. dec. 2000

GLP compliance:

yes (incl. QA statement)

Remarks:

Landesamt für Umwelt, Wasserwirtschaft und Gewerbeaufsicht, Mainz, Germany

Test material

Test material information

Constituent 1

Reference substance name:

1,2-dimethyl-3-propyl imidazolium bis((trifluoromethyl)sulfonyl)amide

EC Number:

805-807-9

Cas Number:

169051-76-7

Molecular formula:

C10H15F6N3O4S2

IUPAC Name:

1,2-dimethyl-3-propyl imidazolium bis((trifluoromethyl)sulfonyl)amide

Test material form:

liquid

Details on test material:

Appearance : colorless oil
Composition: a base stock containing (C, 28.64; H, 3.61; F, 27.18; N, 10.02; O, 15.26; S, 15.29)
Molecular formula : C10H15F6N3O4S2
Molecular Weight : 419.12 g/mol
Purity >99% (purity determined by MNR)
Homogeneity : homogeneous

Specific details on test material used for the study:

Designation in Test facility : 14040602G
Date of receipt : 06 April 2016
condition of receipt : Room temperaure, in proper conditions
batch N° L 16-0158
Homogeneity : homogeneous
Volatility : unknown
Stability H2O: 96h; EtOH: 96h; acetone: 96h; CH3CN: 96h; DMSO: unknown
Solubility H2O:7.76 ± 0.16 g/L at 20 ± 0.5 °C (determined in LAUS study N°15121001G910) ; EtOH: > 1 g/L; acetone: > 1 g/L; CH3CN: < 0.1 g/L; DMSO: > 1 g/L
Production date 26. Feb. 2016
Expiry date 26. Feb. 2030
storage : room temperature (20 ± 0.5 °C)

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

The study was performed using 5 concentrations (4,6 ; 10; 22; 46 and 100 mg/l ). For each test concentration, 20 Daphnia (5 per vessel) were exposed to the test item. Each vessel contains : 20ml of test solution or 20ml dilution water, and 5 Daphnia.

Test solutions

Vehicle:

no

Details on test solutions:

A stock solution containing 100.5 mg/L test item in dilution water (demineralised water enriched with minerals without daphnia) was prepared. The solutions with lower concentrations were prepared by dilution of this stock solution with dilution water.

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Variety: STRAUS
- Strain: Berlin
- Sex: female
- Age of parental stock: < 24 hours
- Source: Umweltbundesamt Berlin
- Animal Husbandry:
Daphnia magna is bred in the LAUS GmbH throughout the year. The animals are kept for the use in toxicity tests. They multiply by parthenogenesis, thus being genetically identical. The husbandry is performed similar to the method described in the OECD guideline, following SOP 115 002 01 (“Zucht und Hälterung von Daphnia magna STRAUS”), Version 12 from 02. Feb. 2015.
Vessels preserving glasses, nominal volume 2 L
Medium M4-Medium (recipe of ELENDT)
Food unicellular green algae (Desmodesmus subspicatus)
Medium renewal twice a week
Photo period 16/8 hours, using neon tubes
Temperature 20 ± 2 °C

ACCLIMATION
- Acclimation period : No

METHOD FOR PREPARATION AND COLLECTION OF EARLY INSTARS OR OTHER LIFE STAGES:
- Selection of Daphnia: 21.5 hours before the start of the test, the adult animals were separated from the young. 2 hours before test start, the adults were caught with the help of a glass tube, and the new born Daphnia, aged between 0 and 19 hours, were sieved from the medium and immediately placed into a 250 mL-beaker containing dilution water. After a settling-in period of 120 minutes, animals which showed no apparent damage were used for the test.
Switching from M4-medium (husbandry) to Dilution water (test) has been shown not to cause any detrimental effects for test Daphnia.
- Study Performance: Using a glass tube, the Daphnia were caught and lifted from the beaker. They were put on a small sieve, and the medium surrounding the animals was sucked off using absorbent paper. Immediately after that, the animals were put into the respective test solution.

Study design

Test type:

static

Water media type:

other: Deionised water with enrichment of certain minerals : CaCl2*2H2O 293.80 mg/L; MgSO4*7H2O 123.30 mg/L; NaHCO3 64.80 mg/L; and KCl 5.80 mg/L. Resulting hardness 2.502 mmol/L or 250 mg CaCO3/L

Remarks:

After preparation, the dilution water was aerated and the pH measured as 7.6

Limit test:

no

Total exposure duration:

48 h

Test conditions

Test temperature:

19,8 - 21,6 °C

pH:

7,8 (control at 0h and 48h)
7,7 - 7,8 (test item concentrations at 0h and 48h)

Dissolved oxygen:

8,6 mg/L (control at 0h)
8,5 mg/L (control at 48h)
8,4 - 8.7 (test item concentrations at 0h and 48h)

Nominal and measured concentrations:

nominal concentrations in mg/L : blank control , 4.6 / 10 / 22 / 46 / 100 mg/L.
Geometric Mean of measured concentrations : 2.8 / 7.4 / 19.8 / 43.6 / 97.4 mg/L.

Details on test conditions:

TEST SYSTEM
Test vessel:
- Type: open
- Material: 50 mL glass beakers, tall shape, .
- Fill volume: 20 mL
- No. of organisms per vessel: 5 animals
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: deionized water with an enrichment of certain minerals (CaCl2*2H2O 293.80 mg/L; MgSO4*7H2O 123.30 mg/L; NaHCO3 64.80 mg/L; and KCl 5.80 mg/L). Resulting hardness 2.502 mmol/L or 250 mg CaCO3/L
- Culture medium different from test medium: Yes. (M4 / dilution water).
- Intervals of water quality measurement: pH and oxygen concentration were measured at test start and test end

OTHER TEST CONDITIONS
- Lighting: diffuse Lighting
- Feeding: none

EFFECT PARAMETERS MEASURED: immobility at 24 and 48 h

VEHICLE CONTROL PERFORMED: no

RANGE-FINDING STUDY
not specified

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Results and discussion

Effect concentrations

Effect concentrations 1

Key result

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

> 97.4 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat. (dissolved fraction)

Basis for effect:

mobility

Effect concentrations 2

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

92.5 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat. (dissolved fraction)

Basis for effect:

mobility

Effect concentrations 3

Key result

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

19.8 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat. (dissolved fraction)

Basis for effect:

mobility

Effect concentrations 4

Key result

Duration:

48 h

Dose descriptor:

LOEC

Effect conc.:

43.6 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat. (dissolved fraction)

Basis for effect:

mobility

Details on results:

In none of the treatments any colouration or precipitation was observed at the start and at the end of the experiment.

Results with reference substance (positive control):

Potassium dichromate was used as positive control in a reference study. The 24h-EC50 value was determined as 1.6 mg/L, lying within the demanded range of 0.6 - 1.7 mg/L stated in the guideline.

Reported statistics and error estimates:

The estimation of the biological results was accomplished using the software ToxRat Professional, version 3.2.1.

Any other information on results incl. tables

IMMOBILIY

in the blank control, none of the Daphnia were immobilised

Table 1 immobility

Nominal concentration en mg/L	Immobility 24 hours					Immobility 48 hours
	absolute				in %	absolute				in %
Blank control	0	0	0	0	0	0	0	0	0	0
4,6	0	0	0	0	0	0	0	0	0	0
10	0	0	0	0	0	0	0	0	0	0
22	0	0	0	0	0	0	0	0	0	0
46	0	0	0	0	0	1	1	0	2	20
100	0	1	1	1	15	3	2	3	2	50

pH and O₂

The pH values in the test media and the blank control and the concentration of dissolved oxygen are given in the following tables :

table 2: pH and O₂-values

Nominal Concentration en mg/L	pH					O2-concentration in mg/L
	0 h		48 h			0 h		48 h
Blank control	7.8		7.8			8.6		8.5
4,6	7.7		7.7			8.5		8.6
10	7.8		7.8			8.4		8.7
22	7.8		7.8			8.4		8.6
46	7.8		7.7			8.7		8.6
100	7.8		7.7			8.7		8.4

ANALYTICAL DETERMINATIONS

the measured concentrations for treatment and blank control are given in the following table :

table 3.1: measured concentrations IC and TC

Nominal Concentration Test Item	Mean of measured TC  t = 0 h	Mean of measured TC  t = 48 h	Mean of measured IC  t = 0 h	Mean of measured IC  t = 48 h
mg/L	mg/L	mg/L	mg/L	mg/L
Blank control	8.70	22.02	9.45	9.85
4,6	10.03	23.22	9.96	10.11
10	11.21	24.63	9.31	10.1
22	15.03	27.9	9.47	9.96
46	21.23	35.23	9.33	9.95
100	36.22	50.79	9.10	9.92

LOQ (limit of quantification) TC = 3.78 mg/L

LOQ (limit of quantification) IC = 1.27 mg/L
n (number of determinations) = 2

table 3.2: standard deviations of measured IC and TC

Nominal Concentration Test Item	standard deviation TC  t = 0 h	standard deviation TC  t = 48 h	standard deviation IC  t = 0 h	standard deviation IC  t = 48 h
mg/L	mg/L	mg/L	mg/L	mg/L
Blank control	0.14	0.05	0.05	0.04
4,6	0.12	0.01	0.01	0.05
10	0.07	0.03	0.03	0.08
22	0.19	0.12	0.12	0.12
46	0.31	0.14	0.14	0.05
100	0.06	0.02	0.02	0.15

Table 3.3 Measured concentrations DOC

Nominal Concentration Test Item	Measured DOC (TC-IC)  t = 0 h	Measured DOC (TC-IC)  t = 48 h	Measured DOC minus blank control  t = 0 h	Measured DOC minus blank control  t = 48 h
mg/L	mg/L	mg/L	mg/L	mg/L
Blank control	0.00	12.17	0.00	0.00
4,6	0.71	13.1	0.71	0.93
10	1.90	14.53	1.90	2.36
22	5.55	17.94	5.55	5.77
46	11.90	25.28	11.90	13.11
100	27.12	40.88	27.12	28.71

Table 3.4 Calculated Test Item concentrations

Nominal Concentration Test Item	Calculated concentration test Item  t = 0 h	Calculated concentration test Item  t = 48 h	% of nominal concentration  t = 0 h	% of nominal concentration  t = 48 h
mg/L	mg/L	mg/L	%	%
Blank control	--	--	--	--
4,6	2.49	3.25	54	71
10	6.63	8.24	66	82
22	19.38	20.15	88	92
46	41.55	45.78	90	100
100	94.69	100.24	95	100

Table 3.5 Geometric mean

Nominal Concentration Test Item	Geometric mean of measured concentrations  t = 0 h
mg/L	mg/L
Blank control	--
4,6	2.8
10	7.4
22	19.8
46	43.6
100	97.4

BIOLOGIAL RESULTS TEST ITEM

Table 9 Biological Results Test item

Parameter	Value	95% confidence interval
24h EC50	>97,4 mg/L	--
48h EC50	92,5 mg/L	69 - 175 mg/L
48h NOEC	19,8 mg/L	--
48h LOEC	43,6 mg/L	--

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Remarks:

Immobilisation in the controls is < 10 %. Concentration of dissolved oxygen at the end of the test is > 3 mg/L. pH-value in the test solutions not vary by more than 1.5 units during the test. The highest variation was 0.1 units.

Conclusions:

The study was performed using 5 concentrations ranging from 4.6 to 100mg/L. For each test concentration, 20 Daphnia were exposed to the test item for 48 hours in a static test system. After 24 and 48 hours,the immobilised Daphnia were counted.

Two concentrations showed toxicity between 20 and 50% immobilisation at the end of the test. None of the animals were immobilised in the blank control.

At the start and at the end of the test, the content of the test item in the test solutions was determined using measurement of dissolved organic carbon (DOC). The measured concentration based on DOC measurement was between 54% and 95%of the nominal concentration at the beginning of the test and between 71% and 100% of the nominal concentration at the end of the test. Therefore, the determination of the results was based on the geometric mean of the measured concentrations.

For the estimation of the EC50s of test item and positive control, the fits showed sufficient statistical correspondence of the data with the dose-response-equation.

Potassium dichromate K2Cr2O7 (CAS No.7778-50-9) was used as positive control  in a current reference study. The 24h-EC50 value was determined as 1.6mg/L, lying within the demanded range of 0.6 – 1.7 mg/L stated in the guideline. 

No observations were made which might cause doubts concerning the validity of the study outcome.All validity criteria were met.
The result of the test is considered valid.

Executive summary:

The study was performed using 5 concentrations ranging from 4.6 to 100 mg/L. For each test concentration, 20 Daphnia were exposed to the test item for 48 hours in a static test system. After 24 and 48 hours, the immobilised Daphnia were counted.

Two concentrations showed toxicity between 20 and 50% immobilisation at the end of the test. None of the animals were immobilised in the blank control. Potassium dichromate K2Cr2O7 (CAS No. 7778-50-9) was used as positive control in a current reference study.The 24h-EC50 value was determined as 1.6 mg/L, lying within the demanded range of 0.6 – 1.7 mg/L stated in the guideline. 

At the start and at the end of the test, the content of the test item in the test solutions was determined using measurement of dissolved organic carbon (DOC). The measured concentration based on DOC measurement was between 54 % and 95 % of the nominal concentration at the beginning of the test and between 71 % and 100 % of the nominal concentration at the end of the test. Therefore, the determination of the results was based on the geometric mean of the measured concentrations.

The following results were determined for the test item 1-Propyl-2,3-Dimethylimidazolium bis(trifluoromethanesulfonyl)imide (species: Daphnia magna).

48h-NOEC=19.8mg/L
48h-LOEC=43.6mg/L
24h-EC50>97.4mg/L
48h-EC50=92.5mg/L