lithium bis(fluorosulfonyl)imide

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:

The study was conducted between 21 May 2010 and 22 July 2010

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2010

Report date:

2010

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: Standard for the testing methods concerning new chemical substances. The latest amendment: November 20, 2006, Daphnia sp., Acute Immobilization Test

Version / remarks:

(Pharmaceutical and Food Safety Bureau, Ministry of Health, Labour and Welfare, No.1121002, November 21, 2003; Manufacturing Industries Bureau, Ministry of Economy, Trade and Industry, No.2, November 13, 2003; Environmental Policy Bureau, Ministry of the Environment, No. 031121002 )

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

lithium(1+) bis(fluorosulfonyl)azanide

EC Number:

924-516-9

Cas Number:

171611-11-3

Molecular formula:

(FSO2)2NLi

IUPAC Name:

lithium(1+) bis(fluorosulfonyl)azanide

Specific details on test material used for the study:

Name: Lithium=bis (fluorosulfone) imide
Abbreviated name: LiFSI
Product name: Lithium=bis (fluorosulfone) imide aqueous solution (LiFSI aqueous solution)
Chemical name: Lithium=bis (fluorosulfone) imide
Lot No.: KS100113
Purity: Solid content; 24.0% aqueous solution (information from the report of Dai-ichi Kogyo Seiyaku Co., Ltd.)

In this report, the concentrations of the test substance were expressed as those of LiFSI, active ingredient, unless otherwise specially stated. LiFSI was defined as the solid contents except water in this study.

Appearance: Colorless and transparent liquid
Acquisition date: January 18, 2010
Expiration date: January 18, 2013
Storage conditions: Stored in a refrigerator with a polypropylene container

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

The stability under storage condition was verified by confirming identity between two 19F-NMR spectra which were measured before and after the exposure period.
Analysis of test concentrations was carried out using LC/MS/MS

Test solutions

Vehicle:

no

Details on test solutions:

Preparation of test solutions
Test solutions were prepared before use on the day of exposure. An amount of test substance (417 mg as aqueous solution; 100 mg as LiFSI) was weighed and transferred to a 1000-mL volumetric flask and dissolved in dechlorinated tap water (Two solutions were prepared, one was for stock solution and another was for the test solutions). These stock solutions of 31.3 , 62.5, 125 and 250 mL were separately transferred to 500-mL flasks and brought to volume with dechlorinated tap water to prepare the test solutions of 6.26, 12.5, 25.0 and 50.0 mg/L respectively. After preparation, the conditions (appearance) of the test solutions were recorded. Four vessels containing 100 mL of solution were used for each exposure group. For the control group, four vessels containing 100 mL of the dechlorinated tap water were used.

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

Obtained from: National Institute for Environmental Studies (16-2, Onogawa,Tsukuba-City, Ibaraki, on June 20, 2008)
Growth stage: Neonates (less than 24 hours old) were obtained from 17 days old parent animals
Sensitivity: The background data of the 48-hour EC50 value of the reference substance (potassium dichromate, special grade, Wako Pure Chemical Industries, Ltd.) in our laboratory; 0.18-0.24 mg/L (n=4, July 2008-February 2010).

Breeding conditions of parent animals to obtain test organisms
Young individuals were removed thoroughly from the stock cultures and then the neonates born by the next day were transferred to another vessel. These neonates (released on May 7, 2010) were maintained as parent of the test organisms. After the parents started to breed, young individuals were removed at least twice a week. On the day before the exposure, young individuals were removed thoroughly from the breeding vessel, and the neonates released after that (less than 24 hours old) were used for the test (exposure initiation date: May 24, 2010). In breeding period, the parent animal mortality was 0%, and no abnormal signs such as the production of ephippia or males were shown.

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test conditions

Hardness:

55 mg/L (as CaCO3)

Test temperature:

19.9-20.0°C

pH:

7.8-7.9

Dissolved oxygen:

7.3-9.1 mg/L (≥ 82% of saturation)

Nominal and measured concentrations:

The measured concentrations of the test substance in the test solutions were 102-106% of the nominal at the exposure initiation and 97.8-101 % of the nominal at the exposure termination. The test substance concentrations in the test vessels were stable during the exposure period. Since the variability of the measured concentrations of the test substance was within ±20% of the nominal, the nominal concentrations were used as the test concentrations.

A 48-hour range-finding test was conducted at nominal concentration of 10 and 100 mg/L under static condition, and the percentages of immobilization were 0 and 100% respectively. The nominal concentrations were maintained for 48 hours. Therefore, the definitive test was conducted at 5 nominal concentrations (common ratio; 2.0) of 6.26, 12.5, 25.0, 50.0 and 100 mg/L. One control group using dechlorinated tap water was also made.

Details on test conditions:

Exposure procedure·
The test was initiated when daphnids were assigned to the test vessels that contained the test solutions.
The conditions (appearance) of the test solutions were recorded at the start, and at 24 and 48 hours after the beginning of the exposure. Water temperature, dissolved oxygen and pH were measured at the start and end of the exposure. At the exposure initiation, one vessel which was prepared in addition to 4 replicate test solutions was measured. Temperature in the thermostat water bath, in which the test vessels ware placed, was continuously recorded during the exposure period with the temperature recorder. At the exposure termination, the measurement was conducted in one vessel in each exposure and control group.
Daphnids were observed to check if there were immobilized daphnids, any abnormal behavior or appearance at 24 and 48 hours after the beginning of the exposure. Daphnids were considered to be immobilized when the daphnids did not swim within 15 seconds after gentle agitation of the test vessel. If daphnids were touched on the bottom of the vessel or trapped on water surface, it indicated immobilization.

Test vessels: 100-mL tall glass beaker
Volume of test solutions: 100 mL / vessel
Replicates: 4 vessels I group
Number of daphnids used: 20 individuals I group (5 individuals I vessel)
Dilution water: Dechlorinated tap water (the concentration of the residual chlorine was <0.01 mg/L, the total hardness were 55 mg/L (as CaC03)).
Lightning: fluorescent light (520-890 Lux), 16 hour light / 8 hours dark
Feeding: None

Reference substance (positive control):

no

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

89 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Effect concentrations 2

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

71 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

Immobility
No immobility was observed in the 6.26, 12.5, 25.0 and 50.0 mg!L groups both after 24 and 48 hours of the exposure. Immobility in the 100 mg/L group after 24 hours of the exposure was 60% and after 48 hours was 100%. In addition, some abnormal behavior was observed among daphnids in the 50.0 and 100 mg/L group after 24 hours and in the 25.0 and 50.0 mg/L group after 48 hours of the exposure. In the control group, no abnormality was observed during the exposure period.

The 24-hour and 48-hour EC50 value were determined to be 89 mg/L and 71 mg!L, respectively, by using graphical method. The 95% confidence interval was not calculated.

Any other information on results incl. tables

Observations of the test solutions

All solutions in exposure and control groups were colorless and transparent during the exposure period.

Temperature, pH and dissolved oxygen concentration in the test solutions

Throughout the exposure period, the temperatures in the test solutions ranged from 19.6 to 19.7°C and the pH ranged from 7.8 to 7.9. The dissolved oxygen concentrations ranged from 8. 8 to 9. 1 mg/L ( ≥99% of saturation) at the exposure initiation and from 7.3 to 7.7 mg/L ( ≥ 82% of saturation) at the exposure termination, therefore maintained within the prescribed range of ≥ 3.0 mg/L.

Validity of the test

The validity of the test was confinned because there were no items met the following situation;

- More than 10% of daphnids in the control group was immobilized.

- Dissolved oxygen concentrations at the end of the exposure were less than 3 mg/L.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The acute immobilization study (static and open system) was performed by exposing Daphnia magna to Lithium=bis (fluorosulfone) imide (LiFSI). It is concluded that the 48-hour EC50 values is 71 mg/L.

Executive summary:

The Daphnia magna, acute immobilization study (static and open system) was performed to estimate the effect of the test substance, Lithium=bis (fluorosulfone) imide (LiFSI). A 24.0% aqueous solution of LiFSI was used as the test substance. In this report, the concentrations of LiFSI were expressed as LiFSI, active ingredient, unless otherwise specially stated. The measured concentrations of the test substance in the test solutions at nominal concentrations of 6.26, 12.5, 25.0, 50.0 and 100 mg/L were 102-106 % of the nominal at the start of the exposure and 97.8-101 % of the nominal at the end of the exposure. Since the variability of concentrations was within ± 20% of the nominal, the median immobilization concentrations (EC50) were calculated on the basis of the nominal concentrations as the test concentrations during the exposure period.

The 24- and 48-hour EC50 are presented below. The 95% confidence interval was not calculated since the EC50 was determined by graphical method.

Exposure duration	EC50 (mg/L)
24 hours	89
48 hours	71