Hydrogen trifluoromethoxyborate(1-), compound with methanol (1:1)

Short-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Justification for type of information:

see attached justification

Cross-reference

Cross-reference 1

Reason / purpose for cross-reference:

read-across source

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

GLP compliance:

not specified

Analytical monitoring:

not specified

Vehicle:

not specified

Test organisms (species):

Daphnia magna

Details on test organisms:

CULTURING
- Culturing: single clone Daphnia magna (clone K6) cultures were held in 1 L glass recipients filled with aerated and biologically filtered tap water, each containing 20 - 25 individuals.
- Conditions: the temperature in the temperature and light controlled chamber (Type WT150'/+5DU-WB, Weiss Technik, Liedekerke, Belgium) was maintained at 20 ± 1 °C with a photoperiod of 14 h light/10 h dark throughout culturing and exposure experiments.
- Water renewal: three times weekly
- Feeding: the daphnids were fed a mixture of P. subcapitata and Chlamydomonas reinhardtii in a 3/1 ratio (4 x 10E5 cells/ml)
- Age of daphnids at test initiation: < 24 h

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96

Hardness:

initial water hardness: 250 mg CaCO3

Test temperature:

20 ± 1 °C

pH:

initial pH: 7.8-8.2

Nominal and measured concentrations:

- Nominal concentrations (linear 1/2 dilution series): 1 - 32 g/L

Details on test conditions:

TEST SYSTEM
- Test vessels: glass recipients
- Test volume: 50 ml
- No of animals/replicate: 10
- No of replicates/concentration: 3
- Test medium: reconsituted water
- Test media renewal: every 24 h

TEST MEDIUM
- Medium: reconstituted water

TEST CONDITIONS
- Feeding: daphnids were fed the same algae mixture as during culturing
- Photoperiod: 14 h light/ 10 h dark

Key result

Duration:

96 h

Dose descriptor:

EC50

Effect conc.:

18 260 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Cross-reference 2

Reason / purpose for cross-reference:

read-across source

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: 1d: the study is comparable to guideline study. Pre-dates OECD Guideline. Test procedure in accordance with generally accepted scientific standards and described in sufficient detail

Reason / purpose for cross-reference:

reference to same study

Principles of method if other than guideline:

Acute testing procedures were based on the guidelines of the ASTM Subcommittee on Safety to Aquatic Organisms. The 48-h acute toxicity data were used to select the appropriate test concentrations for a chronic study.

GLP compliance:

not specified

Specific details on test material used for the study:

Details on properties of test surrogate or analogue material (migrated information):
No test surrogate or analogue material was used.

Analytical monitoring:

no

Vehicle:

no

Test organisms (species):

Daphnia magna

Details on test organisms:

The cladoceran Daphnia magna was used as the test organism. The brood stock was cultured and maintained in aerated (90-105% saturation) 2.91-liter animal jars. A 2.0-liter open-ended tube with 1.0-mm nylon bolting cloth affixed to the bottom was contained within each jar to facilitate harvesting first instars. The screened end of the tube was held approximately 1.5 cm off the bottom by two Pyrex triangles placed one on top of the other. Each tube contained 25 adult daphnids. When the tube was lifted, the adults remained on the screen while the first instars passed into the beaker for harvesting. All daphnids were fed a diet of Selenastrum capricornutum Printz (green alga). Feeding rate was the equivalent of 1.25 mg/L dry weight. The algal size and population distribution were measured with a Coulter counter. Each bood stock animal jar contained the appropriate amount of food and water made up to a 2M-liter volume. The brood stock food, water and glass receptacles were changed every Monday, Wednesday and Friday. The brood stock was kept in an environmental chamber set at 20± 1 °C and a photoperiod of 16 h light: 8 h dark. Twenty four hours before testing, multiparous females were isolated. The neonates produced by these adults were removed and used for acute and chronic testing within 24 h.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

148 ± 7 mg/L as CaCO3

Test temperature:

temperture-controlled environmental chamber set at 20 ± 1 °C

pH:

pH 8.1 ± 0.1 (range 7.9-8.2)

Dissolved oxygen:

Dissolved oxygen concentrations throughout the test were greater than 60% saturation

Salinity:

Test was performed in freshwater.

Nominal and measured concentrations:

The boron concentration in the water was 0.4 ± 0.1 mg/L. Lake Huron contains about 12 mg/L boron.

Details on test conditions:

The static acute test was conducted in 250-ml beakers to which 200 ml of the appropriate amount of test material and water was added. The test consisted of exposing three replicate groups of 10 neonates to each of six nominal concentrations (54, 91, 151, 252, 420 and 700 mg/L as boron) of the test material and a control. In addition an extra beaker was set at the high, medium, low and control concentrations to avoid the risk of contamination while taking dissolved oxygen, pH and temperature measurements. The test beakers were placed in a temperture-controlled environmental chamber set at 20 ± 1 °C and a photoperiod of 16 h light: 8 h dark.
The duration of the test was 48 h. Mortality as well as dissolved oxygen, pH and temperature were recorded after 24 and 48 h of exposure. Daphnids were not fed nor were the solutions aerated during the test.

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

133 mg/L

Nominal / measured:

nominal

Conc. based on:

element

Remarks:

Boron

Remarks on result:

other: 115-153 mg B/L

Details on results:

The calculated 48-h static acute LC50 value of boric acid was 133 mg/L as boron (95% confidence interval 115-153 mg/L) (probit). The no-kilt level for this test was less than 54 mg/L and the 100% kill concentration was 420 mg/L. There was 7% control mortality during the 48-h test. Dissolved oxygen concentrations throughout the test were greater than 60% saturation and the pH ranged from 6.7 to 8.1. Temperatures during the static acute study ranged from 20.1 to 20.7 °C.

Executive summary:

A procedure for conducting chronic daphnid static renewal tests has been developed and evaluated using boric acid as the test material. This procedure is an improvement over other proposed procedures for the following reasons: (a) the test methodology and equipment simplify the operations required to perform the test, (b) data on all endpoints for a particular concentration are obtained from the same group of test organisms and (c) the experimental design permits statistical interpretation of the critical endpoints. The acute and chronic effects of boric acid on Daphnia magna were similar to those reported in the literature. The 48-h static acute LC₅₀value and 95% confidence intervals for boric acid were 133 (115-153) mg/L as boron. The chronic toxicity of boric acid estimated by derivation of the maximum acceptable toxicant concentration was between 6.4 and 13.6 mg/L as boron

Cross-reference 3

Reason / purpose for cross-reference:

read-across source

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: 2d: Test procedure in accordance with national standard methods with acceptable restrictions.

Qualifier:

according to guideline

Guideline:

other: standard U.S. Environmental Protection Agency (U.S. EPA) protocols

GLP compliance:

not specified

Analytical monitoring:

not specified

Details on test solutions:

Test concentrations of ILs were prepared by pipetting the required amount of stock solution (ILs dissolved in water) into known volumes of test water. Water-quality parameters (temperature, pH, and dissolved oxygen) were recorded daily. Dissolved oxygen and temperature were measured with an oxygen meter (Orion Research, Beverly, MA, USA), and pH was measured with a pH tester (Oakton Instruments, Beverly, MA, USA).

Test organisms (species):

Daphnia magna

Details on test organisms:

Daphnia magna neonates (age < 24 h) were obtained from batch cultures maintained in groundwater-filled laboratory aquaria at 20 ± 2 °C and a 16:8-h light:dark photoperiod with a 15-min transition period. Stock animals were originally obtained from Carolina Biological Supply (Burlington, NC, USA). Cultures were fed a mixture of pond water and Spirulina Dry Powder Microalga ® (Petaluma, CA, USA).

Test type:

static

Water media type:

freshwater

Total exposure duration:

48 h

Test temperature:

Each trial was conducted at 20 ± 1 °C

Nominal and measured concentrations:

Ionic liquid test concentrations were based on preliminary range-finding tests of acute toxicity and ranged from 1 to 100 mg/L. The Na -based salt concentrations ranged from 1 to 10,000 mg/L.

Details on test conditions:

The IL-exposure bioassays were conducted as 48-h static acute tests according to standard procedures (Sprague JB. 1969. Measurement of pollutant toxicity to fish. I. Bioassay methods for acute toxicity. Water Res 5:793–821). Each IL exposure used D. magna neonates (age < 24 h) born from parthenogenic females grown in batch cultures. Eight neonates were placed in each of 30 glass beakers (250 mL), with five e replicates for each of six treatment concentrations (control plus five IL concentrations). The number of living and dead neonates was noted at 24 and 48 h after the initiation of each trial. Neonates observed as motionless and without a discernable heartbeat were considered to be dead. Each trial was conducted at 20 ± 1 °C in the laboratory with a 16:8-h light:dark photoperiod.

Reference substance (positive control):

no

Duration:

48 h

Dose descriptor:

other: LC5

Effect conc.:

2 mg/L

Conc. based on:

test mat.

Remarks:

NaBF4

Remarks on result:

other: 1,823.15–3,004.23

Duration:

48 h

Dose descriptor:

LC50

Effect conc.:

4 787 mg/L

Conc. based on:

test mat.

Remarks:

NaBF4

Remarks on result:

other: 4,228.47–5,323.46

Results with reference substance (positive control):

No reference substance was used as the tested substance is considered in this study as some sort of reference substance: "We also tested the toxicity of salts with Na + as the cation and PF6- , BF4- as anions to determine if the imidazolium cation or the various anions influenced toxicity."

Executive summary:

In the present study, we investigated the acute toxicities of imidazolium-based ILs to the water flea Daphnia magna.Acute toxicity of ILs (48-h median lethal concentration [LC50] value) was determined using standard U.S. Environmental Protection Agency (U.S. EPA) protocols.The acute effects of imidazolium-based ILs on survival of the crustacean Daphnia magna and their chronic effects on number of first-brood neonates, total number of neonates, and average brood size were studied.The toxicity of salts with Na+ as the cation and PF6-, BF4- as anions was also tested in order to determine if the imidazolium cation or the various anions influenced toxicity.Lethal concentrations of imidazolium ILs with various anions(X)ranged from a median lethal concentration (LC50) of 8.03 to 19.91 mg L^-1,whereas salts with a sodium cation (Na +X) were more than an order of magnitude higher (NaPF6LC50, 9,344.81 mg L^-1;NaBF4LC50, 4765.75 mg L^-1).Thus, toxicity appeared to be related to the imidazolium cation and not to the various anions (e.g., Cl, Br, PF 6, and BF 4).

Materials and methods

Test material

Test material information

Constituent 1

Reference substance name:

Hydrogen trifluoromethoxyborate(1-), compound with methanol (1:1)

EC Number:

220-543-9

EC Name:

Hydrogen trifluoromethoxyborate(1-), compound with methanol (1:1)

Cas Number:

2802-68-8

Molecular formula:

CH4O.CH3BF3O.H

IUPAC Name:

hydrogen trifluoro(methanolato)borate(1-) methanol (1:1)

Details on test material:

Name of the test substance used in the study report: Borfluorid-Methanol

Results and discussion

Effect concentrations

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Remarks on result:

other: Test result derived from read-across source substances