Trifluoromethanesulphonic anhydride

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 01 sept 2012 to 01 Feb 2013

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.1 (Acute Toxicity for Fish)

Deviations:

no

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

At test initiation (0 hour) and test termination (96 hours), a single sample was removed from each test concentration and the control and analyzed for trifluoromethanesulfonic acid. 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:

Prior to exposure initiation, a 100 mg/L primary stock solution was prepared by adding 3.2044 g of trifluoromethanesulfonic acid to 32 L of dilution water. The pH was adjusted from 3.6 to 6.9 using 18.5 mL of 1.0 M sodium hydroxide. This stock solution was mixed using a glass rod for approximately one minute. Following mixing, the resultant stock solution 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 6.3, 13, 25, 50 and 100 mg/L .
Exposure solutions were mixed thoroughly for approximately one minute using a glass rod. The exposure solutions were observed to be clear and colorless with no visible undissolved test substance. In addition, a control vessel, containing only dilution water, was established and maintained under the same conditions as the treatment level solutions. Exposure aquaria were labeled to identify the concentration and study number.

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

TEST ORGANISM
- Common name: Rainbow trout
- Strain: Oncorhynchus mykiss
- Source: Osage Catfisheries, a commercial supplier located in Osage Beach, Missouri.
- Age at study initiation (mean and range, SD): no data
- Length at study initiation (length definition, mean, range and SD): 38 to 44 mm
- Weight at study initiation (mean and range, SD): 0.58 to 1.3 g
- Feeding during test: Fish were not fed during the 24-hour period prior to test initiation or during the exposure period
- Food type: dry commercial fish food, Trout Chow, ad libitum, daily during culture


ACCLIMATION
- Acclimation period: 48 hours
- Acclimation conditions (same as test or not): same as test
- Type and amount of food: dry commercial fish food, Trout Chow, ad libitum, daily during culture. Fish were not fed during the 24-hour period prior to test initiation or during the exposure period
- Health during acclimation (any mortality observed): Mortality of 0.97% was observed among the test fish population during the 48 hour period prior to testing.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96

Remarks on exposure duration:

h

Hardness:

60 mg/L as CaCO3

Test temperature:

13 to 15°C

pH:

6.5 to 7.3

Dissolved oxygen:

7.7 to 9.9 mg/L

Nominal and measured concentrations:

Nominal: 6.3, 13, 25, 50 and 100 mg/L
Measured: 5.9 12, 23, 45 and 97 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: Each aquarium was constructed of glass and silicone adhesive and measured 39 x 20 x 25 centimeters (L x W x H)
- Type (delete if not applicable): open
- No. of organisms per vessel: 7
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1
- Biomass loading rate: 0.30 g

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: The dilution water (well water) used during the study was from the same source as the water used to culture rainbow trout and was characterized as having a total hardness and total alkalinity as CaCO3 of 60 mg/L and 26 mg/L, respectively, a pH of 7.0 and a conductivity of 400 µs/cm.
- Total organic carbon: 0.57 mg/L
- Alkalinity: 26 mg/L
- Conductivity: 400 µs/cm
- Culture medium different from test medium: no
- Intervals of water quality measurement: monthly

OTHER TEST CONDITIONS
- Adjustment of pH: yes, before to begin the test
- Photoperiod: 16 hours light and 8 hours darkness
- Light intensity: 850 to 900 lux

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : . Effects for this study were based on death, defined as the lack of movement by the exposed organisms

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:
Two trout exposed to the 100 mg/L treatment level were observed to be lethargic following 96 hours. Based on these results and in consultation with the Study Sponsor, a definitive exposure was conducted at nominal concentrations of 6.3, 13, 25, 50 and 100 mg/L.

Reference substance (positive control):

not required

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

behaviour

Details on results:

The results of the analysis of the exposure solutions for trifluoromethanesulfonic acid showed that measured concentrations were generally consistent throughout the exposure phase and maintained the expected concentration gradient. The mean measured concentrations ranged from 89 to 95% of nominal concentrations and defined the treatment levels tested as 5.8, 12, 23, 45 and 95 mg/L.
Analysis of the six quality control samples resulted in measured concentrations which were consistent with the predetermined recovery range and ranged from 86.6 to 97.1% of the nominal fortified levels (3.17, 27.2 and 99.8 mg/L). Based on these results, it was established that the appropriate precision and quality control was maintained during the analyses of the exposure solutions.
Following 96 hours of exposure, no mortality or adverse effects were observed in any of the treatment levels (6 to 100 mg/L) or the control.

The 96-hour LC50 value for trifluoromethanesulfonic acid was empirically estimated to be > 100 mg/L (nominal). The No Observed-Effect Concentration (NOEC) was determined to be 100 mg/L. The highest concentration producing 0% mortality was 100 mg/L. The lowest concentration producing 100% mortality was > 100 mg/L.

Additional testing to further define the LC50 value was not performed since the highest nominal concentration tested (100 mg/L) represents the highest concentration required by the test guidelines.

Sublethal observations / clinical signs:

Nominal concentrations tested, corresponding cumulative percent and number of mortalities, and observations made during the 96‑hour static acute exposure of rainbow trout(Oncorhynchus mykiss)to trifluoromethanesulfonic acid.

	Cumulative Mortality (%)^a
Nominal Concentration (mg/L)	0-Hour	24-Hour	48-Hour	72-Hour	96-Hour
Control	0	0	0	0	0
	(0)	(0)	(0)	(0)	(0)
6.3	0	0	0	0	0
	(0)	(0)	(0)	(0)	(0)
13	0	0	0	0	0
	(0)	(0)	(0)	(0)	(0)
25	0	0	0	0	0
	(0)	(0)	(0)	(0)	(0)
50	0	0	0	0	0
	(0)	(0)	(0)	(0)	(0)
100	0	0	0	0	0
	(0)	(0)	(0)	(0)	(0)

^a    Actual number of mortalities is presented in parentheses.

Validity criteria fulfilled:

yes

Remarks:

- Mortality in the control was < 10% - Constant conditions were maintained - Oxygen was higher than 60% of air saturation throughout the study.

Conclusions:

The 96-hour LC50 for trifluoromethanesulfonic acid was higher than 100 mg/L (nominal concentration), and the NOEC was 100 mg/L.
Trifluoromethanesulfonic acid is not considered to be harmful to fish.

Executive summary:

The purpose of the study was to estimate the acute toxicity (LC50) of trifluoromethanesulfonic acid to rainbow trout,Oncorhynchus mykiss, under static test conditions. The study followed the OECD Guideline for Testing of Chemicals #203, the EU Method C.1 and was performed under GLP conditions.

After a preliminary test, nominal trifluoromethanesulfonic acid test concentrations of 6.3, 13, 25, 50 and 100 mg/L were chosen for the definitive exposure.

No mortality was observed during the study, therefore, the 96-hour LC50 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 fish.

Reference 2

Endpoint:

short-term toxicity to fish

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:

96 h

Dose descriptor:

LC50

Effect conc.:

> 100 mg/L

Basis for effect:

mortality (fish)

Conclusions:

By analogy with its degradation product in water, the 96-hour LC50 for trifluoromethanesulfonic anhydride is considered to be higher than 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 96-hour LC50 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 (LC50) of trifluoromethanesulfonic acid to rainbow trout,Oncorhynchus mykiss, was performed under static test conditions, following the OECD Guideline 203 and under GLP conditions.

After a preliminary test, nominal test concentrations of 6.3, 13, 25, 50 and 100 mg/L were chosen for the definitive exposure.

No mortality was observed during the study, therefore, the 96-hour LC50 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 fish.