Carboxymethyldimethyl-3-[[(3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl)sulphonyl]amino]propylammonium hydroxide

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

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

Remarks:

Conducted according to guideline in effect at the time of study conduct

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Deviations:

no

Remarks:

Conducted according to guideline in effect at the time of study conduct

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

The concentrations of the test substance were measured using liquid chromatography with tandem mass spectrometric detection (LC-MS/MS). At the start of the definitive test, two samples (10 mL) were taken from the freshly-prepared control and test media. After 48 hours, the contents of the test vessels from each group were pooled and further samples were taken for analysis. On each occasion, one of the samples was analysed and the other was stored in a freezer in case further analysis was required. Further analysis of the samples at the two nominal concentrations of 25.0 and 50.0 mg/L was required to identify if a sampling error occurred during the test.

Concentrations are expressed in terms of the measured levels of test substance. The measured concentrations of test substance ranged between 88 and 103% of their nominal values in samples of freshly prepared media. At 48 hours, the measured concentrations ranged between 51 and 68% of their nominal values except at 25 and 50 mg/L, where the measured concentrations were inconsistent with the levels found at the start of the test. Analysis of the reserve samples at these levels confirmed the results of the original samples: 30.4 mg/L measured at nominal 25 mg/L and 14.1 mg/L measured at nominal 50 mg/L. It was concluded that in error, samples for these two groups had been placed into the wrong pre-labelled sampling vials. Since no immobility was observed at either 25 or 50 mg/L, this error was considered not to have had an impact on the test, so for calculation of the study endpoints the means of the measured concentration at 48 hours have been interchanged to maintain an increase in measured concentrations in line with the nominal concentrations. Following correction of this error, the measured concentrations at 48 hours had decreased to between 51 and 68% of their nominal values in samples of expired media; between 50 and 71% of their starting values. Based on a geometric mean, the overall measured levels of test substance were 5.08, 9.78, 17.8, 37.7, 69.0 and 145 mg/L and these values were used in the determination of study end-points.

Vehicle:

yes

Details on test solutions:

The test organisms were maintained and the tests conducted in Elendt M4 medium. The medium was prepared in deionised, reverse osmosis water.

The method of preparation used during the definitive test was based on the results of formulation trials and a range finding test. The test substance (200 or 100 mg) was added to dilution medium (ca. 900 mL) in a volumetric flask (1 L) and made up to volume with gentle mixing. The contents of the flask were slowly stirred (to avoid foaming) overnight to give test medium with a nominal concentration of 200 mg/L or 100 mg/L of test substance. Aliquots (250 or 125 mL) of 200 mg/L solution were added to dilution medium (ca. 300 or ca. 200 mL, respectively) in a volumetric flask (1 L) and made up to volume (with gentle mixing) to give the test medium with a nominal concentration of 50.0 or 25.0 mg/L of test substance. Aliquots (125 or 62.5 mL) of 100 mg/L solution were added to dilution medium (ca. 200 mL) in a volumetric flask (1 L) and made up to volume (with gentle mixing) to give the test medium with a nominal concentration of 12.5 and 6.25 mg/L of test substance.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna (Straus)
- Source: Cultured in-house and were obtained from a strain originating from the National Institute for Applied Chemical Research (IRCHA), France
- Age at study initiation (mean and range, SD): <24 hours old
- Feeding during test: Cultures were fed daily with a suspension of the unicellular green algae, Pseudokirchneriella subcapitata, to provide nominally 0.1 to 0.2 mg carbon per daphnid, per day, except during the initial two days when a slightly lower ration was given.

ACCLIMATION: The day before the start of the study, all juvenile Daphnia were removed from the laboratory cultures. The following morning, juveniles produced by the gravid (egg-bearing) adult Daphnia were removed from the culture vessels and held in a separate holding vessel; these animals, which were <24 hours old, were used in the test.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Post exposure observation period:

None

Hardness:

263 mg/L as CaCO3

Test temperature:

Study start (0 h): 20.0-20.1°C
Study end: (48 h): 19.9-20.7°C

pH:

Study start (0 h): 7.74-8.10
Study end (48 h): 7.63-7.94

Dissolved oxygen:

Study start (0 h): 8.20-9.39 mg/L
Study end (48 h): 8.14-8.97 mg/L

Nominal and measured concentrations:

Nominal: 0, 6.25, 12.5, 25, 50, 100, 200 mg/L
Measured: 0, 5.08, 9.78, 17.8, 37.7, 69, 145 mg/L

Details on test conditions:

Twenty Daphnia, four replicates of five animals per vessel, were exposed in each control and test group. As the test substance was a surfactant and foamed during use, the study was conducted in sealed vessels to prevent the Daphnia from floating due to changes in the surface tension of the media. The first instar Daphnia were placed in groups of five, at random into glass Wheaton vials (ca. 100 mL) which were completely filled with the appropriate dilution medium and then sealed with Teflon bungs, secured using aluminium caps, leaving no headspace, to give a loading rate of 20 mL medium per organism. Daphnia were exposed to the test or control conditions for a period of 48 hours without renewal of test media

Reference substance (positive control):

no

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

144 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95% CL: 108-250 mg/L

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

> 145 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

After 48 hours, there was 25% immobilisation at 69.0 mg/L (mean measured) and 45% at 145 mg/L (mean measured). The highest concentration at which no immobilisation occurred was 37.7 mg/L.

Cumulative immobilisation
Concentration (mg/L)		Cumulative numbers of immobile Daphnia
		24 hours						48 hours
Nominal	Measured	R1	R2	R3	R4	Total	%	R1	R2	R3	R4	Total	%
Control	nd	0	0	0	0	0	0	0	0	0	0	0	0
6.25	5.08	0	0	0	0	0	0	0	0	0	0	0	0
12.5	9.78	0	0	0	0	0	0	0	0	0	0	0	0
25	17.8^a	0	0	0	0	0	0	0	0	0	0	0	0
50	37.7^a	0	0	0	0	0	0	0	0	0	0	0	0
100	69.0	0	0	0	0	0	0	0	0	4	1	5	25
200	145	0	0	0	0	0	0	2	2	4	1	9	45
nd: None detected (less than the limit of detection of 0.4 mg/L) R: Replicate number ^aConcentration following correction for the operator error.

Validity criteria fulfilled:

yes

Conclusions:

48-hr EC50: 144 mg/L
This study and the conclusions which are drawn from it fulfil the quality criteria (validity, reliability, repeatability).

Executive summary:

Groups of twenty Daphnia, less than 24 hours old, were exposed for 48 hours to the test substance at nominal concentrations of 6.25, 12.5, 25.0, 50.0, 100 and 200 mg/L. The test media were prepared in Elendt M4 medium either by the direct addition of the test substance to the dilution medium or by dilution of aqueous stock solutions. The test concentrations were measured using liquid chromatography with tandem mass spectrometric detection (LC-MS/MS). The measured concentrations of test substance ranged between 88 and 103% of their nominal values in samples of freshly prepared media and decreased to between 51 and 68% of their nominal values in samples of expired media (between 50 and 71% of their starting values). The overall geometric mean measured levels of test substance were 5.08, 9.78, 17.8, 37.7, 69.0 and 145 mg/L and these values were used in the determination of study end-points.

Observations of the Daphnia in each control and test vessels were made after approximately 24 and 48 hours. After 48 hours, there was 25% immobilization at 69.0 mg/L (mean measured) and 45% at 145 mg/L (mean measured). The highest concentration at which no immobilization occurred was 37.7 mg/L. The 48-hour EC₅₀, LOEC, and NOEC were 144, 69.0, and 37.7 mg/L, respectively. The 24-hour EC₅₀, LOEC, and NOEC were >145 mg/L.

Description of key information

48-hour EC50: 144 mg/L

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

144 mg/L