Potassium trifluoroacetate

Long-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 2010-03-24 to 2010-07-09

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: This study was performed according to OECD 211 guideline with GLP statement. All validity criteria were fulfilled and all the relevant information is reported.

Qualifier:

according to guideline

Guideline:

OECD Guideline 211 (Daphnia magna Reproduction Test)

Version / remarks:

adopted October 03, 2008

Deviations:

yes

Remarks:

concerning the analysis of test item concentrations, instead of analyse all test concentrations, only one concentration (the highest) was measured. The other test media were not analysed since they were below the NOEC determination in this test

Qualifier:

according to guideline

Guideline:

EU Method C.20 (Daphnia magna Reproduction Test)

Version / remarks:

dated May 30, 2008

Deviations:

not specified

GLP compliance:

yes (incl. QA statement)

Remarks:

2009-08-05

Specific details on test material used for the study:

Details on properties of test surrogate or analogue material (migrated information):
Sodium trifluoroacetate and potassium trifluoroacetate have the same chemical structure. Only the associated cation Na instead of K changes.
The available data, including basic physico-chemical properties, tox and ecotox data, verified that the read-accross is justified, because the two substances present the same profile.

PHYSICO-CHEMICAL PROPERTIES of Sodium trifluoroacetate
- Molecular formula: C2F3O2Na
- Molecular weight: 136 g/mol
- Smiles notation (if other than submission substance): C(C(=O)[O-])(F)(F)F.[Na+]
- Substance type: salt
- Melting point: 207 - 209°C
- Boiling point: no data
- Vapour pressure: 0.00268 Pa at 25°C (highest calculated value from EPIsuite)
- Water solubility: 625 g/L (no data on the method)
- log Pow: -3.31 (KOWWIN estimation)
- pKa: no data, but it is a salt of the same acid than TFAK.
- Stability of test material at room temperature: stable under test conditions
- pH dependance on stability: no data

OTHER PROPERTIES (if relevant for this endpoint)
- Results of test for ready biodegradability: not readily biodegradable
- Not harmful to daphnia, as TFAK

See the endpoint study summary "Aquatic toxicity" for the read-across justification.

Analytical monitoring:

yes

Details on sampling:

- Concentrations: control, 1, 3.2, 10, 32, 100 mg test item/L
- Sampling method: Duplicate samples from the freshly prepared test media of all test concentrations and the control were taken at the second treatment period (day 3) and at a treatment period in the second and third week (days 12 and 14). For the determination of the stability of the test item under the test conditions and of the maintenance of the test item concentrations during the renewal periods, duplicate samples of the respective aged test media and controls were sampled at day 5, 14 and 17. One of these three stability control treatments lasted for 72 hours (weekend), two for 48 hours, corresponding to th different test medium renewal periods.
- Sample storage conditions before analysis: All samples were stored in a freezer (<= -10°C), protected from light until analysis was performed.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: Before test stard and before every test medium renewal, the test medium of the highest test concentration of nominal 100 mg/L was prepared by dissolving approximately 150 mg test item into approximately 1500 mL test water by intense stirring for 10 minutes. Adequate volumes of this test medium were diluted with test water to prepare the test media. The test media were prepared just before introduction of Daphnia (= start of the test and each test medium renewal).
- Eluate: no data
- Differential loading: factor 3.2 (Test concentrations = 100, 32, 10, 3.2, 1.0 mg test item/L)
- Controls: yes, one control (test water was used without addition of the test item)
- Chemical name of vehicle (organic solvent, emulsifier or dispersant): not applicable
- Concentration of vehicle in test medium (stock solution and final test solution(s) including control(s)): not applicable
- Evidence of undissolved material (e.g. precipitate, surface film, etc): no data

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna
- Strain/clone: clone 5
- Justification for species other than prescribed by test guideline: no data
- Source: the Daphnia introduced in the test was taken from our in-house laboratory culture.
- Age of parental stock (mean and range, SD): 2-19.25 hours old.
- Feeding during test: The Daphnia in the stock culture were fed at least all working days.
- Food type: Green algae (Desmodesmus subspicatus) freshly grown in the laboratories of IBACON.
- Amount: the amount of food was based on the concentration of total organic carbon (TOC) in the algal food suspension. The fed daily amounts of algal TOC/Daphnia were as follows: days 0-3 = 0.10 mg; days 4-7 = 0.15 mg; days 8-20 = 0.20 mg
- Frequency: daily.
- Other: The Daphnia were bred in the laboratories of IBACON under similar temperature and light conditions as in the test. The cultivation of the parental Daphnia was performed in reconstituted water of a similar quality regarding to pH, components of the main ions and total hardness as the test water used in the test. The test organisms were not first brood progeny.

ACCLIMATION
- Acclimation period: no data
- Acclimation conditions (same as test or not): Acclimatisation is not necessary since the breeding is performed in the same kind of test water.
- Type and amount of food: no data
- Feeding frequency: no data
- Health during acclimation (any mortality observed): no data

QUARANTINE (wild caught)
not applicable

METHOD FOR PREPARATION AND COLLECTION OF EARLY INSTARS OR OTHER LIFE STAGES: no data

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

21 d

Remarks on exposure duration:

no remarks

Post exposure observation period:

None

Hardness:

Water hardness = 2.5 mmol/L (=250 mg/L) as CaCO3.

Test temperature:

The water temperatures were measured in all test concentrations and the control in all freshly prepared and aged test media. In the aged test media, measurement was performed in the pooled test vessels of each concentration and the control. See table 1 in "Any other information on materials and methods incl. tables" field. Water temperature were 21°C in the freshly prepared media and 20-21°C in the aged media.

pH:

The pH-values were measured in all test concentrations and the control in all freshly prepared and aged test media. In the aged test media, measurement was performed in the pooled test vessels of each concentration and the control. See table 2 in "Any other information on materials and methods incl. tables" field. The pH-values were 7.9 to 8.2 in the freshly prepared media; 7.8 to 9.2 in the aged media; and thus the pH value did not vary by more than 1.5 units.

Dissolved oxygen:

The dissolved oxygen concentrations were measured in all test concentrations and the control in all freshly prepared and aged test media. In the aged test media, measurement was performed in the pooled test vessels of each concentration and the control. See table 3 in "Any other information on materials and methods incl. tables" field. The dissolved oxygen concentrations were 8.2 to 8.8 mg/L in the freshly prepared media and 8.0 to 10.1 mg/L in the aged media.

Salinity:

not applicable

Nominal and measured concentrations:

Nominal concentrations: 100, 32, 10, 3.2, 1.0 mg test item/L and one control.
In the freshly prepared test media 110% of the nominal test concentrations were found. In the aged test media 110% of the nominal values were determined. Under the test conditions the test item was sufficiently stable during the test medium renewal periods of 48 and 72 hours. See table 5 in "Any other information on results incl. tables" field. Therefore, all reported results are related to nominal concentrations of the test item.

Details on test conditions:

TEST SYSTEM
- Test vessel: glass beakers
- Type (delete if not applicable): no data
- Material, size, headspace, fill volume: 100 mL volume with approximately 60 mL test medium.
- Aeration: no data
- Type of flow-through (e.g. peristaltic or proportional diluter): not applicable
- Renewal rate of test solution (frequency/flow rate): The test media of all test concentrations and of the control were renewed on Days 3, 5, 7, 10, 12, 14, 17 and 19 of the exposure period (every Monday, Wednesday and Friday). At these dates the test animals were carefully transfered by glass tubes from the old test vessels into the freshly prepared test media of the corresponding concentrations.
- No. of organisms per vessel: 1
- No. of vessels per concentration (replicates): 10
- No. of vessels per control (replicates): 10
- No. of vessels per vehicle control (replicates): not applicable
- Biomass loading rate: no data

TEST MEDIUM / WATER PARAMETERS
See table 4 in "Any other information on materials and methods incl. talbes" field.
- Source/preparation of dilution water: reconstituted water (in deionised water analytical grade salts and additives were added)
- Alkalinity: 0.9 mmol/L
- Culture medium different from test medium: no
- Intervals of water quality measurement: no data

OTHER TEST CONDITIONS
- Adjustment of pH: no data
- Photoperiod: 16h light - 8h dark
- Light intensity: 1000 - 1100 lux

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : The mortality of the test animals and the number of young daphnids were recorded each day. Dead animals and offspring were removed at the same times.

VEHICLE CONTROL PERFORMED: not applicable

RANGE-FINDING STUDY
- Test concentrations: no data
- Results used to determine the conditions for the definitive study: Pre-experiments were performed to determine the solubility of the test item in test water and to select suitable methods for the preparation of a stock solution and the dosage of the test item into the test media. Besides, for the determination of the test concentrations a range-finding test was performed. However, according to the OECD guideline 211 concentrations in excess of nominal 100 mg test item/L were not tested.

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

30% w/w NaTFA

Basis for effect:

reproduction

Remarks:

rate

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

>= 30 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

NaTFA

Basis for effect:

reproduction

Remarks:

rate

Remarks on result:

other: recalculated

Duration:

21 d

Dose descriptor:

LOEC

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

30% w/w NaTFA

Basis for effect:

reproduction

Remarks:

rate

Duration:

21 d

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

30% w/w NaTFA

Basis for effect:

reproduction

Remarks:

rate

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

30% w/w NaTFA

Basis for effect:

other: survival of adults

Duration:

21 d

Dose descriptor:

LOEC

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Remarks:

30% w/w NaTFA

Basis for effect:

other: survival of adults

Details on results:

-Survival of Adults:
In the control and all test concentrations all Daphnia survived until the end of the test after the exposure time of 21 days.

-Reproduction rate:
Table 6 in "Any other information on results incl. tables"field, shows the total number of live offspring produced by all adults within 21 days of continuous exposure to 30% w/w Sodium trifluoroacetate aqueous solution (cumulative values).
The total numbers of live offspring produced by each surviving adult for each treatment group and the calculated reproduction rates are given in Table 7 in "Any other information on results incl. tables" field. The reproduction rate of those Daphnia in the control was 101 +/- 25.3 (mean +/- SD) live offspring per adult. According to the results of a Williams t-test (one-sided, alpha=0.05) no significant toxic effect of the test item on the mean reproduction rate was determined up to and including the highest test concentration of nominal 100 mg test item/L. The EC50 of the reproduction rate was determined to be > 100 mg test item/L.

-Date of first brood:
The date of first brood in each treatment group is given in Table 8 in "Any other information on results incl. tables" field. The first young Daphnia released from their parent animals were recorded in the all test concentrations at the observation on day 9. In the control, the first offspring was recorded at day 10.

-Signs of intoxication:
No particular signs of intoxication were observed at the test animals during the test.

-Appearance of the test item in the test media:
No remarks observations

Results with reference substance (positive control):

- Results with reference substance valid? yes
- Relevant effect levels: EC50 (48h) = 1.37 mg/L ; NOEC (48h) = 0.62 mg/L ; LOEC (48h) = 1.4 mg/L
- Other: nominal concentrations tested = 3.0, 1.4, 0.62, 0.28, 0.13 mg/L and one control

Reported statistics and error estimates:

The NOEC and the LOEC for the reproduction rate and age at first reproduction were evaluated by the Williams t-test. The software used to performed the statistical analysis was ToxRat Professional, Version 2.10, ToxRat Solutions GmbH, 2009.

Table 5: Results for the determination of the test item in the test samples

Sample description / age				Concentration found (mg tfa/L)	D.F	Calculated (mg tfa/L)	Concentration nominal (mg tfa/L)	% of nominal
mg test item/L	replicate	day	h
Control Control Control Control Control Control   100 100 100 100 100 100 100 100 100 100 100 100	1 1 1 1 1 1   1 2 1 2 1 2 1 2 1 2 1 2	3 5 12 14 14 17   3 3 5 5 12 12 14 14 14 14 17 17	0 48 0 48 0 72   0 0 48 48 0 0 48 48 0 0 72 72	< LOD < LOD < LOD < LOD 0.965 < LOD   31.195 30.119 32.271 31.880 31.293 34.814 33.640 33.836 32.369 37.749 33.640 32.858	1 1 1 1 1 1   1 1 1 1 1 1 1 1 1 1 1 1	n.a. n.a. n.a. n.a. < LOQ n.a.   31.195 30.119 32.271 31.880 31.293 34.814 33.640 33.836 32.369 37.749 33.640 32.858	0.000 0.000 0.000 0.000 0.000 0.000   30.000 30.000 30.000 30.000 30.000 30.000 30.000 30.000 30.000 30.000 30.000 30.000	n.a. n.a. n.a. n.a. n.a. n.a.   104 100 108 106 104 116 112 113 108 126 112 110
Mean value (n=12):								110
RSD (n=12):								6

Table 6: Total number of live immature Daphnia produced by all adults (cumulative values)

Exposure day	Nominal concentration of the test item (mg/L)
	Control	1.0	3.2	10	32	100
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21	0 0 0 0 0 0 0 0 0 0 104 123 172 339 346 576 751 764 866 962 982 1011	0 0 0 0 0 0 0 0 0 29 97 97 173 316 442 630 771 791 848 941 1001 1041	0 0 0 0 0 0 0 0 0 19 71 119 206 324 475 619 823 839 929 1003 1061 1091	0 0 0 0 0 0 0 0 0 47 105 105 156 393 434 510 846 864 869 988 1005 1040	0 0 0 0 0 0 0 0 0 15 96 113 168 344 499 545 753 787 787 894 970 1016	0 0 0 0 0 0 0 0 0 8 104 123 192 339 415 549 839 839 897 1004 1030 1050
% of control	100	103	108	103	100	104

In this table, the live brood of all parent daphnids is displayed, whereas the final evaluation is based only on the live brood that was produced by adults surviving the whole study period.

Table 7: Number of live immature Daphnia produced by each surviving adult after 21 days

Replicate	Nominal concentration of the test item (mg/L)
	Control	1.0	3.2	10	32	100
1 2 3 4 5 6 7 8 9 10	102 106 141 122 94 107 93 113 89 44	99 106 106 68 85 133 104 120 103 117	126 150 95 114 112 106 104 104 81 99	99 93 134 115 109 132 100 77 99 82	127 89 105 108 87 107 47 109 115 122	107 117 91 125 92 96 115 90 126 91
Mean SD	101 25.3	104 18.1	109 18.7	104 18.9	102 22.9	105 14.7
% of control	100	103 n.s.	108 n.s.	103 n.s.	100 n.s.	104 n.s.

n.s. = not significant (Williams t-test, alpha = 0.05)

Table 8: Number of live offspring produced by all surviving adults within 21 days of exposure

Exposure day	Nominal concentration of the test item (mg/L)
	Control	1.0	3.2	10	32	100
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21	0 0 0 0 0 0 0 0 0 0 104 123 172 339 346 576 751 764 866 962 982 1011	0 0 0 0 0 0 0 0 0 29 97 97 173 316 442 630 771 791 848 941 1001 1041	0 0 0 0 0 0 0 0 0 19 71 119 206 324 475 619 823 839 929 1003 1061 1091	0 0 0 0 0 0 0 0 0 47 105 105 156 393 434 510 846 864 869 988 1005 1040	0 0 0 0 0 0 0 0 0 15 96 113 168 344 499 545 753 787 787 894 970 1016	0 0 0 0 0 0 0 0 0 8 104 123 192 339 415 549 839 839 897 1004 1030 1050
No. of surviving adults	10	10	10	10	10	10
Average number of offspring per surviving adult*	101	104	109	104	102	105

* mean from maximum 10 replicates

Validity criteria fulfilled:

yes

Remarks:

all criteria were met: survival rate of adult Daphnia in the control was >80% (100%) and the mean number of live offspring in the control after 21d was >60 per surviving adult (101 per surviving adult)

Conclusions:

The influence of 30% w/w Sodium trifluorocetate aqueous solution on the survival and reproduction rate of Daphnia magna were determined during an exposure period of 21 days. The 21-day NOEC was determined to be >= 100 mg test item/L (>= 25 mg trifluoroacetic acid/L) for the reproduction rate and for the survival of the adult test animals. The EC50 for the reproduction rate was > 100 mg test item/L.

Executive summary:

The influence of 30% w/w Sodium trifluoroacetate aqueous solution to Daphnia magna (taken from IBACON laboratory culture) was evaluated in a semi-static reproduction test, according to OECD guideline for testing of chemicals No. 211 and with GLP statement. The mortality of the test animals and the number of young daphnids were recorded each day. Dead animals and offspring were removed at the same times. This study encompassed 5 test concentrations (100, 32, 10, 3.2 and 1.0 mg test item/L) and one control with 10 replicates, each containing one Daphnia. The Daphnia were exposed for 21 days in a semi-static test.

The pH-values, dissolved oxygen concentrations and water temperatures were measured in all test concentrations and the control in all freshly prepared and aged test media. The pH-values were in the range of 7.8 to 9.2; the dissolved oxygen concentrations were in the range of 8.0 to 10.1 mg/L and the water temperatures were in the range of 20 to 21°C. The light regime was 16 h light-8 h dark and the light intensity was 1000 -1100 lux. This test conditions were within the ranges requested by guideline OECD 211.

The concentrations of trifluoroaetate of the test item 30% w/w Sodium trifluoroacetate aqueous solution were only measured in the duplicate test medium samples of 100 mg test item/L from all sampling date. From the control samples only one of the duplicate samples was analysed from each sampling date. The other test media were not analysed, since they were below the NOEC determination in this test. In the freshly prepared test media 110% of the nominal test concentrations were found. In the aged test media 110% of the nominal values were determined. Under the test conditions the test item was sufficiently stable during the test medium renewal periods of 48 and 72 hours. Therefore, all reported results are related to nominal concentrations of the test item.

The biological results shows a 21-day NOEC for survival of adults and reproduction rate >= 100 mg test item/L and a 21-day EC50 for reproduction rate > 100 mg test item/L. Besides, no particular signs of intoxication were observed at the test animals during the test.

Description of key information

By analogy with TFANa, TFAK is considered as having no effect on the reproduction of aquatic invertebrates at 100 mg/L.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Dose descriptor:

NOEC

Effect concentration:

30 mg/L

Additional information

No data on potassium trifluoroacetate is available for this endpoint. However, a reliable key study is available for sodium trifluoroacetate which is used in a read-across approach. The results expressed in TFANa is directly applied to TFAK in a worst case approach (i.e. the molecular weight of Na is lower than the molecular weight of K).

The influence of 30% w/w Sodium trifluoroacetate aqueous solution to Daphnia magna was evaluated in a semi-static reproduction test, according to OECD guideline for testing of chemicals No. 211 and with GLP statement. The mortality of the test animals and the number of young daphnids were recorded each day. Dead animals and offspring were removed at the same times. This study encompassed 5 test concentrations (100, 32, 10, 3.2 and 1.0 mg test item/L) and one control with 10 replicates, each containing one Daphnia. The Daphnia were exposed for 21 days in a semi-static test.

The pH-values, dissolved oxygen concentrations and water temperatures were measured in all test concentrations and the control in all freshly prepared and aged test media. The pH-values were in the range of 7.8 to 9.2; the dissolved oxygen concentrations were in the range of 8.0 to 10.1 mg/L and the water temperatures were in the range of 20 to 21°C. The light regime was 16 h light-8 h dark and the light intensity was 1000 -1100 lux. This test conditions were within the ranges requested by guideline OECD 211.

The concentrations of trifluoroaetate of the test item 30% w/w Sodium trifluoroacetate aqueous solution were only measured in the duplicate test medium samples of 100 mg test item/L from all sampling date. From the control samples only one of the duplicate samples was analysed from each sampling date. The other test media were not analysed, since they were below the NOEC determination in this test. In the freshly prepared test media 110% of the nominal test concentrations were found. In the aged test media 110% of the nominal values were determined. Under the test conditions the test item was sufficiently stable during the test medium renewal periods of 48 and 72 hours. Therefore, all reported results are related to nominal concentrations of the test item.

The biological results shows a 21-day NOEC for survival of adults and reproduction rate >= 100 mg test item/L and a 21-day EC50 for reproduction rate > 100 mg test item/L. Besides, no particular signs of intoxication were observed at the test animals during the test. By analogy, potassium trifluoroacetate is considered as having no effect on the reproduction of aquatic invertebrates at 100 mg/L (corresponding to 30 mg TFANa/L).