Trifluoromethanesulphonic anhydride

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 24 sept 2012 to 23 January 2013

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

At test initiation (0 hour) and test termination (48 hours), a single sample was removed from each test concentration and the control and analyzed for trifluoromethanesulfonic acid. The sample analyzed at 0 hour was removed from the test solution prior to division into the replicate vessels. Samples analyzed at test termination were composited prior to analysis. Each sample was collected from the approximate midpoint of the vessels and analyzed for trifluoromethanesulfonic acid.

Three quality control (QC) samples were also prepared in dilution water at each sampling interval at nominal concentrations which approximated the test concentration range and remained with the exposure solution samples throughout the analytical process. Analysis of the QC samples was used to judge the precision and quality control maintained during the analytical process.

Vehicle:

no

Details on test solutions:

A 100 mg/L stock solution was prepared prior to test initiation by adding 0.2500 g of the test substance to 2.5 L of dilution water. The pH of the stock solution was adjusted from 6.7 to 8.1 using 1.56 mL of 1.0 N sodium hydroxide. The resultant solution was mixed with a stir plate and magnetic stir bar for approximately ten minutes and was observed to be clear and colorless with no visible undissolved test substance. The 100 mg/L primary stock solution was used to prepare exposure solutions of 6.3, 13, 25, 50 and 100 mg/L.

Test solutions were mixed with a glass rod for approximately one minute prior to division into replicate exposure vessels. Following mixing, all test solutions were observed to be clear and colorless with no visible undissolved test substance. Each test solution was divided into four replicate vessels, each containing approximately 200 mL of solution. A set of control solutions was also prepared containing dilution water only and maintained under the same conditions as the treatment level solutions. Exposure vessels were labeled to identify the concentration and study number.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna
- Source: obtained from laboratory cultures maintained at Smithers Viscient.
- Age at study initiation (mean and range, SD): < 24h old
- Method of breeding: own culture of the lab
- Feeding during test: no
- Feeding during culture: Daphnids were fed unicellular green algae, Ankistrodesmus falcatus (4 x 107 cells/mL) in addition to a suspension of YCT (yeast, cereal leaves and flaked fish food).


ACCLIMATION
- Acclimation period: no, because own culture in the lab in the same conditions as the test

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

180 mg/L as CaCO3

Test temperature:

19 to 20ºC

pH:

8.2 to 8.3

Dissolved oxygen:

8.8 to 9.2 mg/L

Nominal and measured concentrations:

Nominal concentrations: 0, 6.3, 13, 25, 50 and 100 mg/L
Measured concentrations: 0, 5.7, 12, 23, 44 and 92 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: 250-mL glass beakers
- Type (delete if not applicable): open
- Material, size, headspace, fill volume: Test vessels were 250-mL glass beakers, each containing 200 mL of test solution.
- Aeration: no
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4


TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: The dilution water used during the definitive test was from the same source as the water in the daphnid cultures
- Total organic carbon:
- Alkalinity: 96 mg/L as CaCO3
- Dissolved oxygen: 10 mg/L
- Conductivity: 620 µs/cm
- Culture medium different from test medium: no
- Intervals of water quality measurement: monthly

OTHER TEST CONDITIONS
- Adjustment of pH:
- Photoperiod:16 hours of light and 8 hours of darkness
- Light intensity: 70 to 81 footcandles (753 to 872 lux)

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : immobilization

TEST CONCENTRATIONS
- Spacing factor for test concentrations: 2
- Range finding study
- Test concentrations: 0.010, 0.10, 1.0, 10 and 100 mg/L
- Results used to determine the conditions for the definitive study: Following 48 hours of exposure, 5, 0, 5, 0 and 0% immobilization was observed among daphnids exposed to the 0.010, 0.10, 1.0, 10 and 100 mg/L treatment levels, respectively. Based on the results of preliminary testing, nominal trifluoromethanesulfonic acid test concentrations of 6.3, 13, 25, 50, and 100 mg/L were selected for the definitive exposure.

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

Analytical Results:
Measured concentrations were generally consistent throughout the exposure phase and maintained the expected concentration gradient. Mean measured concentrations ranged from 89 to 92% of nominal and defined the treatment levels as 5.7, 12, 23, 44 and 92 mg/L.
Analysis of the six quality control samples resulted in measured concentrations which were consistent with the predetermined recovery range and ranged from 90.9 to 100% of the nominal fortified levels (3.17, 27.2 and 99.8 mg/L). These results established that the appropriate precision and quality control was maintained during the analysis of the exposure solutions.

Biological Results:
Following 48 hours of exposure, no immobilization or adverse effects were observed among daphnids exposed to the any of the treatment levels.

In nominal, the 48-hour EC50 value was empirically estimated to be > 100 mg/L. The No-Observed-Effect Concentration (NOEC) was determined to be 100 mg/L. The highest concentration producing 0% immobilization was 100 mg/L.

Results with reference substance (positive control):

- Results with reference substance valid? YES.
The 24 hour reference test was conducted from 8 to 9 November 2012 and the results established that the 24-hour EC50 value for Daphnia magna and potassium dichromate was 2.4 mg/L. This result was within the expected range for daphnids and potassium dichromate.

Mean measured concentrations tested, corresponding cumulative percent and number of immobilized organisms, and observations made during the 48‑hour static acute exposure of daphnids (Daphnia magna) to trifluoromethanesulfonic acid.

 

Nominal Concentration (mg/L)	Cumulative Percent Immobilization (Number of Immobilized Daphnids)^a
24-Hour						48-Hour
A	B	C	D	Mean		A	B	C	D	Mean
Control	0	0	0	0	0		0	0	0	0	0
	(0)	(0)	(0)	(0)			(0)	(0)	(0)	(0)
6.3	0	0	0	0	0		0	0	0	0	0
	(0)	(0)	(0)	(0)			(0)	(0)	(0)	()
13	0	0	0	0	0		0	0	0	0	0
	(0)	(0)	(0)	(0)			(0)	(0)	(0)	(0)
25	0	0	0	0	0		0	0	0	0	0
	(0)	(0)	(0)	(0)			(0)	(0)	(0)	(0)
50	0	0	0	0	0		0	0	0	0	0
	(0)	(0)	(0)	(0)			(0)	(0)	(0)	(0)
100	0	0	0	0	0		0	0	0	0	0
	(0)	(0)	(0)	(0)			(0)	(0)	(0)	(0)

 ^a      The actual number of immobilized daphnids is presented in parentheses.

Validity criteria fulfilled:

yes

Remarks:

- In the control, not more that 10 per cent of the daphnids were immobilised; - The dissolved oxygen concentration at the end of the test was higher than 3 mg/l in control and test vessels.

Conclusions:

The 48-hour EC50 value was determined to be > 100 mg/L. The No-Observed-Effect Concentration (NOEC) was determined to be 100 mg/L. Trifluoromethanesulfonic acid is not considered to be harmful to Daphnids.

Executive summary:

The purpose of the study was to estimate the acute toxicity (EC50) of trifluoromethanesulfonic acid to daphnids (Daphnia magna) under static test conditions. This study was conducted according to OECD Guideline for Testing of Chemicals 202, the EU Method C.2 and the GLP.

The nominal concentrations tested were 6.3, 13, 25, 50, and 100 mg/L.

No immobilised daphnids were observed during the study, therefore the 48-hour EC50 value was > 100 mg/L and the No-Observed-Effect Concentration (NOEC) was determined to be 100 mg/L.

In these test conditions, Trifluoromethanesulfonic acid is not harmful to daphnids.

Reference 2

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:

The read-across justification is provided in the attached document.

Reason / purpose for cross-reference:

read-across source

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Conclusions:

By analogy with its degradation product in water, the 48-hour EC50 value of trifluoromethanesulfonic anhydride is considered to be > 100 mg/L.

Description of key information

Trifluoromethanesulfonic anhydride being rapidly and completely hydrolysed in water, the effect concentration obtained with its degradation product, i.e. trifluoromethanesulfonic acid, is considered as relevant for the assessment of its aquatic toxicity. Therefore, the 48-hour EC50 for trifluoromethanesulfonic anhydride is considered to be higher than 100 mg/L.

Additional information

The read-across justification with trifluoromethanesulfonic acid is provided in the attached document in the endpoint study record.

 

The determination of the acute toxicity (EC50) of trifluoromethanesulfonic acid to daphnids (Daphnia magna) was performed under static test conditions according to the OECD Guideline 202 and under GLP.

The nominal concentrations tested were 6.3, 13, 25, 50, and 100 mg/L.

No immobilised daphnids were observed during the study, therefore the 48-hour EC50 value was > 100 mg/L and the No-Observed-Effect Concentration (NOEC) was determined to be 100 mg/L.

In these test conditions, Trifluoromethanesulfonic acid is not harmful to daphnids.